From 6e05ac1937507c48e09e82f2749ebedf337cb5af Mon Sep 17 00:00:00 2001
From: Mehdi Bouaziz <mehdi.bouaziz@nomadic-labs.com>
Date: Fri, 8 Apr 2022 18:25:41 +0200
Subject: [PATCH 1/6] Proto/Tests: change init2 return value

Wrap the two contracts in a pair to look more like `init` signature
---
 .../lib_protocol/test/helpers/context.ml      |  2 +-
 .../lib_protocol/test/helpers/context.mli     |  3 ++-
 .../test_global_constants_storage.ml          |  2 +-
 .../integration/operations/test_transfer.ml   | 20 +++++++++----------
 .../integration/operations/test_tx_rollup.ml  | 12 +++++------
 5 files changed, 20 insertions(+), 19 deletions(-)

diff --git a/src/proto_alpha/lib_protocol/test/helpers/context.ml b/src/proto_alpha/lib_protocol/test/helpers/context.ml
index 036c51671537..a020e02e4dd6 100644
--- a/src/proto_alpha/lib_protocol/test/helpers/context.ml
+++ b/src/proto_alpha/lib_protocol/test/helpers/context.ml
@@ -443,7 +443,7 @@ let init2 ?rng_state ?commitments ?(initial_balances = []) ?consensus_threshold
     2
   >|=? function
   | (_, []) | (_, [_]) -> assert false
-  | (b, contract_1 :: contract_2 :: _) -> (b, contract_1, contract_2)
+  | (b, contract_1 :: contract_2 :: _) -> (b, (contract_1, contract_2))
 
 let init_with_constants constants n =
   let accounts = Account.generate_accounts n in
diff --git a/src/proto_alpha/lib_protocol/test/helpers/context.mli b/src/proto_alpha/lib_protocol/test/helpers/context.mli
index 3a811002d3a6..776d00429573 100644
--- a/src/proto_alpha/lib_protocol/test/helpers/context.mli
+++ b/src/proto_alpha/lib_protocol/test/helpers/context.mli
@@ -271,7 +271,8 @@ val init2 :
   ?tx_rollup_sunset_level:int32 ->
   ?sc_rollup_enable:bool ->
   unit ->
-  (Block.t * Alpha_context.Contract.t * Alpha_context.Contract.t) tzresult Lwt.t
+  (Block.t * (Alpha_context.Contract.t * Alpha_context.Contract.t)) tzresult
+  Lwt.t
 
 val init_with_constants :
   Constants.parametric ->
diff --git a/src/proto_alpha/lib_protocol/test/integration/michelson/test_global_constants_storage.ml b/src/proto_alpha/lib_protocol/test/integration/michelson/test_global_constants_storage.ml
index dd34a69fa667..3d384948ab29 100644
--- a/src/proto_alpha/lib_protocol/test/integration/michelson/test_global_constants_storage.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/michelson/test_global_constants_storage.ml
@@ -60,7 +60,7 @@ let expr_to_hash expr =
    that values written to the global table of constants persist across
    blocks. *)
 let get_happy_path () =
-  Context.init2 () >>=? fun (b, alice, bob) ->
+  Context.init2 () >>=? fun (b, (alice, bob)) ->
   Incremental.begin_construction b >>=? fun b ->
   let expr_str = "Pair 3 7" in
   let expr = Expr.from_string expr_str in
diff --git a/src/proto_alpha/lib_protocol/test/integration/operations/test_transfer.ml b/src/proto_alpha/lib_protocol/test/integration/operations/test_transfer.ml
index 79ff3bd90cc6..d84bcbf92392 100644
--- a/src/proto_alpha/lib_protocol/test/integration/operations/test_transfer.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/operations/test_transfer.ml
@@ -79,7 +79,7 @@ let two_over_n_of_balance incr contract n =
 (********************)
 
 let single_transfer ?fee ?expect_failure amount =
-  Context.init2 () >>=? fun (b, contract_1, contract_2) ->
+  Context.init2 () >>=? fun (b, (contract_1, contract_2)) ->
   Incremental.begin_construction b >>=? fun b ->
   transfer_and_check_balances
     ~loc:__LOC__
@@ -143,7 +143,7 @@ let test_transfer_to_originate_with_fee () =
 
 (** Transfer from balance. *)
 let test_transfer_amount_of_contract_balance () =
-  Context.init2 () >>=? fun (b, contract_1, contract_2) ->
+  Context.init2 () >>=? fun (b, (contract_1, contract_2)) ->
   Context.Contract.pkh contract_1 >>=? fun pkh1 ->
   (* given that contract_1 no longer has a sufficient balance to bake,
      make sure it cannot be chosen as baker *)
@@ -173,7 +173,7 @@ let test_transfers_to_self () =
 
 (** Forgot to add the valid transaction into the block. *)
 let test_missing_transaction () =
-  Context.init2 () >>=? fun (b, contract_1, contract_2) ->
+  Context.init2 () >>=? fun (b, (contract_1, contract_2)) ->
   (* given that contract_1 no longer has a sufficient balance to bake,
      make sure it cannot be chosen as baker *)
   Context.Contract.pkh contract_1 >>=? fun pkh1 ->
@@ -318,7 +318,7 @@ let test_transfer_from_implicit_to_originated_contract () =
 (********************)
 
 let multiple_transfer n ?fee amount =
-  Context.init2 () >>=? fun (b, contract_1, contract_2) ->
+  Context.init2 () >>=? fun (b, (contract_1, contract_2)) ->
   Incremental.begin_construction b >>=? fun b ->
   n_transactions n b ?fee contract_1 contract_2 amount >>=? fun b ->
   Incremental.finalize_block b >>=? fun _ -> return_unit
@@ -366,7 +366,7 @@ let test_block_with_multiple_transfers_with_without_fee () =
 (** Build a chain that has 10 blocks. *)
 let test_build_a_chain () =
   Context.init2 ~consensus_threshold:0 ()
-  >>=? fun (b, contract_1, contract_2) ->
+  >>=? fun (b, (contract_1, contract_2)) ->
   let ten = of_int 10 in
   List.fold_left_es
     (fun b _ ->
@@ -396,7 +396,7 @@ let test_empty_implicit () =
 
 (** Balance is too low to transfer. *)
 let test_balance_too_low fee () =
-  Context.init2 () >>=? fun (b, contract_1, contract_2) ->
+  Context.init2 () >>=? fun (b, (contract_1, contract_2)) ->
   Incremental.begin_construction b >>=? fun i ->
   Context.Contract.balance (I i) contract_1 >>=? fun balance1 ->
   Context.Contract.balance (I i) contract_2 >>=? fun balance2 ->
@@ -475,7 +475,7 @@ let test_balance_too_low_two_transfers fee () =
 
 (** The counter is already used for the previous operation. *)
 let invalid_counter () =
-  Context.init2 () >>=? fun (b, contract_1, contract_2) ->
+  Context.init2 () >>=? fun (b, (contract_1, contract_2)) ->
   Incremental.begin_construction b >>=? fun b ->
   Op.transaction (I b) contract_1 contract_2 Tez.one >>=? fun op1 ->
   Op.transaction (I b) contract_1 contract_2 Tez.one >>=? fun op2 ->
@@ -489,7 +489,7 @@ let invalid_counter () =
 (** Same as before but through a different way to perform this
     error. *)
 let test_add_the_same_operation_twice () =
-  Context.init2 () >>=? fun (b, contract_1, contract_2) ->
+  Context.init2 () >>=? fun (b, (contract_1, contract_2)) ->
   Incremental.begin_construction b >>=? fun b ->
   transfer_and_check_balances ~loc:__LOC__ b contract_1 contract_2 ten_tez
   >>=? fun (b, op_transfer) ->
@@ -502,7 +502,7 @@ let test_add_the_same_operation_twice () =
 
 (** The counter is in the future *)
 let invalid_counter_in_the_future () =
-  Context.init2 () >>=? fun (b, contract_1, contract_2) ->
+  Context.init2 () >>=? fun (b, (contract_1, contract_2)) ->
   Incremental.begin_construction b >>=? fun b ->
   Context.Contract.counter (I b) contract_1 >>=? fun cpt ->
   let counter = Z.add cpt (Z.of_int 10) in
@@ -515,7 +515,7 @@ let invalid_counter_in_the_future () =
 
 (** Check ownership. *)
 let test_ownership_sender () =
-  Context.init2 () >>=? fun (b, contract_1, contract_2) ->
+  Context.init2 () >>=? fun (b, (contract_1, contract_2)) ->
   Incremental.begin_construction b >>=? fun b ->
   (* get the manager of the contract_1 as a sender *)
   Context.Contract.manager (I b) contract_1 >>=? fun manager ->
diff --git a/src/proto_alpha/lib_protocol/test/integration/operations/test_tx_rollup.ml b/src/proto_alpha/lib_protocol/test/integration/operations/test_tx_rollup.ml
index 2ae860039dfb..d6c21dec0270 100644
--- a/src/proto_alpha/lib_protocol/test/integration/operations/test_tx_rollup.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/operations/test_tx_rollup.ml
@@ -257,7 +257,7 @@ let context_init2 ?tx_rollup_max_inboxes_count
     ?tx_rollup_hard_size_limit_per_message
     2
   >|=? function
-  | (b, contract_1 :: contract_2 :: _) -> (b, contract_1, contract_2)
+  | (b, contract_1 :: contract_2 :: _) -> (b, (contract_1, contract_2))
   | (_, _) -> assert false
 
 (** [originate b contract] originates a tx_rollup from [contract],
@@ -1558,7 +1558,7 @@ let test_finalization () =
     level, and ensures that this fails.  It adds a commitment with
     the wrong batch count and ensures that that fails. *)
 let test_commitment_duplication () =
-  context_init2 () >>=? fun (b, contract1, contract2) ->
+  context_init2 () >>=? fun (b, (contract1, contract2)) ->
   let pkh1 = is_implicit_exn contract1 in
   originate b contract1 >>=? fun (b, tx_rollup) ->
   Context.Contract.balance (B b) contract1 >>=? fun balance ->
@@ -1647,7 +1647,7 @@ let test_commitment_duplication () =
   return ()
 
 let test_commit_current_inbox () =
-  context_init2 () >>=? fun (b, contract1, contract2) ->
+  context_init2 () >>=? fun (b, (contract1, contract2)) ->
   originate b contract1 >>=? fun (b, tx_rollup) ->
   (* In order to have a permissible commitment, we need a transaction. *)
   Incremental.begin_construction b >>=? fun i ->
@@ -2378,7 +2378,7 @@ module Rejection = struct
   let init_with_deposit ?tx_rollup_hard_size_limit_per_message addr =
     init_l2_store () >>= fun store ->
     context_init2 ?tx_rollup_hard_size_limit_per_message ()
-    >>=? fun (b, account, account2) ->
+    >>=? fun (b, (account, account2)) ->
     originate b account >>=? fun (b, tx_rollup) ->
     make_deposit b tx_rollup account addr
     >>=? fun (b, (deposit, _), ticket_hash) ->
@@ -2607,7 +2607,7 @@ module Rejection = struct
     let open Error_monad_operators in
     let (_, _, addr) = gen_l2_account () in
     init_l2_store () >>= fun store ->
-    context_init2 () >>=? fun (b, contract1, contract2) ->
+    context_init2 () >>=? fun (b, (contract1, contract2)) ->
     originate b contract1 >>=? fun (b, tx_rollup) ->
     make_deposit b tx_rollup contract1 addr
     >>=? fun (b, (deposit_message, _), _ticket_hash) ->
@@ -3558,7 +3558,7 @@ end
     rejecting commitments. *)
 let test_state () =
   let open Single_message_inbox in
-  context_init2 () >>=? fun (b, account1, account2) ->
+  context_init2 () >>=? fun (b, (account1, account2)) ->
   originate b account1 >>=? fun (b, tx_rollup) ->
   (* Submit bogus message three time to have three inboxes *)
   submit b tx_rollup account1 >>=? fun b ->
-- 
GitLab


From 31dfd89880756955768170f111bc452ca3542f7b Mon Sep 17 00:00:00 2001
From: Mehdi Bouaziz <mehdi.bouaziz@nomadic-labs.com>
Date: Fri, 8 Apr 2022 19:03:30 +0200
Subject: [PATCH 2/6] Proto/Tests: simplify calls to Context.init

Look at context.mli first.
init1, init2, init3 are used whenever possible.
init is renamed into init_n to discourage its usage.
---
 .../lib_benchmark/execution_context.ml        |   3 +-
 .../lib_benchmark/test/test_helpers.ml        |   3 +-
 .../lib_plugin/test/test_plugin.ml            |   4 +-
 .../lib_protocol/test/helpers/context.ml      |  81 ++-------
 .../lib_protocol/test/helpers/context.mli     |  63 ++-----
 .../test/helpers/contract_helpers.ml          |   7 +-
 .../test/helpers/liquidity_baking_machine.ml  |   7 +-
 .../test/helpers/sapling_helpers.ml           |   2 +-
 .../test/helpers/tx_rollup_l2_helpers.ml      |   2 +-
 .../test/integration/consensus/test_baking.ml |  20 +--
 .../consensus/test_deactivation.ml            |  14 +-
 .../integration/consensus/test_delegation.ml  | 159 ++++--------------
 .../consensus/test_double_baking.ml           |  38 ++---
 .../consensus/test_double_endorsement.ml      |  16 +-
 .../consensus/test_double_preendorsement.ml   |   7 +-
 .../integration/consensus/test_endorsement.ml |  22 +--
 .../consensus/test_helpers_rpcs.ml            |   7 +-
 .../consensus/test_participation.ml           |   7 +-
 .../consensus/test_preendorsement.ml          |   2 +-
 .../consensus/test_preendorsement_functor.ml  |   2 +-
 .../test/integration/consensus/test_seed.ml   |   6 +-
 .../test/integration/gas/test_gas_levels.ml   |   5 +-
 .../integration/michelson/test_annotations.ml |   3 +-
 .../test_global_constants_storage.ml          |   5 -
 .../michelson/test_interpretation.ml          |   2 +-
 .../michelson/test_patched_contracts.ml       |   2 +-
 .../integration/michelson/test_sapling.ml     |  14 +-
 .../michelson/test_ticket_accounting.ml       |   8 +-
 .../michelson/test_ticket_balance_key.ml      |   2 +-
 .../test_ticket_lazy_storage_diff.ml          |   3 +-
 .../michelson/test_ticket_operations_diff.ml  |   7 +-
 .../michelson/test_ticket_scanner.ml          |   5 +-
 .../michelson/test_ticket_storage.ml          |   2 +-
 .../integration/michelson/test_timelock.ml    |   3 +-
 .../michelson/test_typechecking.ml            |   7 +-
 .../integration/operations/test_activation.ml |  35 ++--
 .../operations/test_combined_operations.ml    | 113 +++++--------
 .../operations/test_failing_noop.ml           |   9 +-
 .../operations/test_origination.ml            |  26 +--
 .../integration/operations/test_reveal.ml     |  12 +-
 .../integration/operations/test_sc_rollup.ml  |   5 +-
 .../integration/operations/test_transfer.ml   |  61 ++-----
 .../integration/operations/test_tx_rollup.ml  |  14 +-
 .../integration/operations/test_voting.ml     |  25 +--
 .../test/integration/test_frozen_bonds.ml     |  17 +-
 .../test/integration/test_liquidity_baking.ml |  34 ++--
 .../test/pbt/test_carbonated_map.ml           |   2 +-
 .../test/pbt/test_gas_properties.ml           |   2 +-
 .../test/pbt/test_script_comparison.ml        |   2 +-
 .../lib_protocol/test/unit/test_gas_monad.ml  |   2 +-
 .../test/unit/test_sc_rollup_arith.ml         |   2 +-
 .../test/unit/test_sc_rollup_inbox.ml         |   2 +-
 .../test/unit/test_sc_rollup_storage.ml       |   2 +-
 .../test/unit/test_tx_rollup_l2.ml            |   2 +-
 54 files changed, 302 insertions(+), 605 deletions(-)

diff --git a/src/proto_alpha/lib_benchmark/execution_context.ml b/src/proto_alpha/lib_benchmark/execution_context.ml
index 747318a66901..39df9a2c54f0 100644
--- a/src/proto_alpha/lib_benchmark/execution_context.ml
+++ b/src/proto_alpha/lib_benchmark/execution_context.ml
@@ -30,7 +30,7 @@ type context = Alpha_context.context * Script_interpreter.step_constants
 let initial_balance = 4_000_000_000_000L
 
 let context_init_memory ~rng_state =
-  Context.init
+  Context.init_n
     ~rng_state
     ~initial_balances:
       [
@@ -41,6 +41,7 @@ let context_init_memory ~rng_state =
         initial_balance;
       ]
     5
+    ()
   >>=? fun (block, accounts) ->
   match accounts with
   | [bs1; bs2; bs3; bs4; bs5] ->
diff --git a/src/proto_alpha/lib_benchmark/test/test_helpers.ml b/src/proto_alpha/lib_benchmark/test/test_helpers.ml
index 189147add733..5baf5e4ce0fd 100644
--- a/src/proto_alpha/lib_benchmark/test/test_helpers.ml
+++ b/src/proto_alpha/lib_benchmark/test/test_helpers.ml
@@ -41,7 +41,7 @@ let print_script_expr_list fmtr (exprs : Protocol.Script_repr.expr list) =
 
 let typecheck_by_tezos =
   let context_init_memory ~rng_state =
-    Context.init
+    Context.init_n
       ~rng_state
       ~initial_balances:
         [
@@ -52,6 +52,7 @@ let typecheck_by_tezos =
           4_000_000_000_000L;
         ]
       5
+      ()
     >>=? fun (block, _accounts) ->
     Context.get_constants (B block) >>=? fun csts ->
     let minimal_block_delay =
diff --git a/src/proto_alpha/lib_plugin/test/test_plugin.ml b/src/proto_alpha/lib_plugin/test/test_plugin.ml
index 6f634d775d50..907ef219418b 100644
--- a/src/proto_alpha/lib_plugin/test/test_plugin.ml
+++ b/src/proto_alpha/lib_plugin/test/test_plugin.ml
@@ -52,10 +52,10 @@ let test_flush () =
       let filter_state =
         add_manager_restriction filter_state op_info.operation_hash op_info pkh
       in
-      Context.init 1 >>= function
+      Context.init1 () >>= function
       | Error e ->
           failwith "Error at context initialisation: %a" pp_print_trace e
-      | Ok (b, _contracts) -> (
+      | Ok (b, _contract) -> (
           let predecessor =
             Block_header.
               {shell = b.header.shell; protocol_data = Bytes.make 10 ' '}
diff --git a/src/proto_alpha/lib_protocol/test/helpers/context.ml b/src/proto_alpha/lib_protocol/test/helpers/context.ml
index a020e02e4dd6..f6f4aa2bfd1c 100644
--- a/src/proto_alpha/lib_protocol/test/helpers/context.ml
+++ b/src/proto_alpha/lib_protocol/test/helpers/context.ml
@@ -354,12 +354,12 @@ module Tx_rollup = struct
     Tx_rollup_services.commitment rpc_ctxt ctxt tx_rollup
 end
 
-let init ?rng_state ?commitments ?(initial_balances = []) ?consensus_threshold
-    ?min_proposal_quorum ?bootstrap_contracts ?level ?cost_per_byte
-    ?liquidity_baking_subsidy ?endorsing_reward_per_slot
+let init_gen n get ?rng_state ?commitments ?(initial_balances = [])
+    ?consensus_threshold ?min_proposal_quorum ?bootstrap_contracts ?level
+    ?cost_per_byte ?liquidity_baking_subsidy ?endorsing_reward_per_slot
     ?baking_reward_bonus_per_slot ?baking_reward_fixed_portion ?origination_size
     ?blocks_per_cycle ?cycles_per_voting_period ?tx_rollup_enable
-    ?tx_rollup_sunset_level ?tx_rollup_origination_size ?sc_rollup_enable n =
+    ?tx_rollup_sunset_level ?tx_rollup_origination_size ?sc_rollup_enable () =
   let accounts = Account.generate_accounts ?rng_state ~initial_balances n in
   let contracts =
     List.map
@@ -385,65 +385,20 @@ let init ?rng_state ?commitments ?(initial_balances = []) ?consensus_threshold
     ?tx_rollup_origination_size
     ?sc_rollup_enable
     accounts
-  >|=? fun blk -> (blk, contracts)
-
-let init1 ?rng_state ?commitments ?(initial_balances = []) ?consensus_threshold
-    ?min_proposal_quorum ?level ?cost_per_byte ?liquidity_baking_subsidy
-    ?endorsing_reward_per_slot ?baking_reward_bonus_per_slot
-    ?baking_reward_fixed_portion ?origination_size ?blocks_per_cycle
-    ?cycles_per_voting_period ?tx_rollup_enable ?tx_rollup_sunset_level
-    ?sc_rollup_enable () =
-  init
-    ?rng_state
-    ?commitments
-    ~initial_balances
-    ?consensus_threshold
-    ?min_proposal_quorum
-    ?level
-    ?cost_per_byte
-    ?liquidity_baking_subsidy
-    ?endorsing_reward_per_slot
-    ?baking_reward_bonus_per_slot
-    ?baking_reward_fixed_portion
-    ?origination_size
-    ?blocks_per_cycle
-    ?cycles_per_voting_period
-    ?tx_rollup_enable
-    ?tx_rollup_sunset_level
-    ?sc_rollup_enable
-    1
-  >|=? function
-  | (_, []) -> assert false
-  | (b, contract_1 :: _) -> (b, contract_1)
-
-let init2 ?rng_state ?commitments ?(initial_balances = []) ?consensus_threshold
-    ?min_proposal_quorum ?level ?cost_per_byte ?liquidity_baking_subsidy
-    ?endorsing_reward_per_slot ?baking_reward_bonus_per_slot
-    ?baking_reward_fixed_portion ?origination_size ?blocks_per_cycle
-    ?cycles_per_voting_period ?tx_rollup_enable ?tx_rollup_sunset_level
-    ?sc_rollup_enable () =
-  init
-    ?rng_state
-    ?commitments
-    ~initial_balances
-    ?consensus_threshold
-    ?min_proposal_quorum
-    ?level
-    ?cost_per_byte
-    ?liquidity_baking_subsidy
-    ?endorsing_reward_per_slot
-    ?baking_reward_bonus_per_slot
-    ?baking_reward_fixed_portion
-    ?origination_size
-    ?blocks_per_cycle
-    ?cycles_per_voting_period
-    ?tx_rollup_enable
-    ?tx_rollup_sunset_level
-    ?sc_rollup_enable
-    2
-  >|=? function
-  | (_, []) | (_, [_]) -> assert false
-  | (b, contract_1 :: contract_2 :: _) -> (b, (contract_1, contract_2))
+  >|=? fun blk -> (blk, get contracts)
+
+let init_n n = init_gen n (fun cs -> cs)
+
+let init1 =
+  init_gen 1 (function [contract_1] -> contract_1 | _ -> assert false)
+
+let init2 =
+  init_gen 2 (function
+      | [contract_1; contract_2] -> (contract_1, contract_2)
+      | _ -> assert false)
+
+let init3 =
+  init_gen 3 (function [c1; c2; c3] -> (c1, c2, c3) | _ -> assert false)
 
 let init_with_constants constants n =
   let accounts = Account.generate_accounts n in
diff --git a/src/proto_alpha/lib_protocol/test/helpers/context.mli b/src/proto_alpha/lib_protocol/test/helpers/context.mli
index 776d00429573..2709a92c4316 100644
--- a/src/proto_alpha/lib_protocol/test/helpers/context.mli
+++ b/src/proto_alpha/lib_protocol/test/helpers/context.mli
@@ -202,9 +202,7 @@ module Tx_rollup : sig
     Tx_rollup_commitment.Submitted_commitment.t option tzresult Lwt.t
 end
 
-(** [init n] : returns an initial block with [n] initialized accounts
-    and the associated implicit contracts *)
-val init :
+type 'accounts init :=
   ?rng_state:Random.State.t ->
   ?commitments:Commitment.t list ->
   ?initial_balances:int64 list ->
@@ -224,55 +222,28 @@ val init :
   ?tx_rollup_sunset_level:int32 ->
   ?tx_rollup_origination_size:int ->
   ?sc_rollup_enable:bool ->
-  int ->
-  (Block.t * Alpha_context.Contract.t list) tzresult Lwt.t
+  unit ->
+  (Block.t * 'accounts) tzresult Lwt.t
+
+(** [init_n n] : returns an initial block with [n] initialized accounts
+    and the associated implicit contracts *)
+val init_n : int -> Alpha_context.Contract.t list init
 
 (** [init1] : returns an initial block with 1 initialized bootstrap account
     and the associated implicit contract *)
-val init1 :
-  ?rng_state:Random.State.t ->
-  ?commitments:Commitment.t list ->
-  ?initial_balances:int64 list ->
-  ?consensus_threshold:int ->
-  ?min_proposal_quorum:int32 ->
-  ?level:int32 ->
-  ?cost_per_byte:Tez.t ->
-  ?liquidity_baking_subsidy:Tez.t ->
-  ?endorsing_reward_per_slot:Tez.t ->
-  ?baking_reward_bonus_per_slot:Tez.t ->
-  ?baking_reward_fixed_portion:Tez.t ->
-  ?origination_size:int ->
-  ?blocks_per_cycle:int32 ->
-  ?cycles_per_voting_period:int32 ->
-  ?tx_rollup_enable:bool ->
-  ?tx_rollup_sunset_level:int32 ->
-  ?sc_rollup_enable:bool ->
-  unit ->
-  (Block.t * Alpha_context.Contract.t) tzresult Lwt.t
+val init1 : Alpha_context.Contract.t init
 
 (** [init2] : returns an initial block with 2 initialized bootstrap accounts
     and the associated implicit contracts *)
-val init2 :
-  ?rng_state:Random.State.t ->
-  ?commitments:Commitment.t list ->
-  ?initial_balances:int64 list ->
-  ?consensus_threshold:int ->
-  ?min_proposal_quorum:int32 ->
-  ?level:int32 ->
-  ?cost_per_byte:Tez.t ->
-  ?liquidity_baking_subsidy:Tez.t ->
-  ?endorsing_reward_per_slot:Tez.t ->
-  ?baking_reward_bonus_per_slot:Tez.t ->
-  ?baking_reward_fixed_portion:Tez.t ->
-  ?origination_size:int ->
-  ?blocks_per_cycle:int32 ->
-  ?cycles_per_voting_period:int32 ->
-  ?tx_rollup_enable:bool ->
-  ?tx_rollup_sunset_level:int32 ->
-  ?sc_rollup_enable:bool ->
-  unit ->
-  (Block.t * (Alpha_context.Contract.t * Alpha_context.Contract.t)) tzresult
-  Lwt.t
+val init2 : (Alpha_context.Contract.t * Alpha_context.Contract.t) init
+
+(** [init3] : returns an initial block with 3 initialized bootstrap accounts
+    and the associated implicit contracts *)
+val init3 :
+  (Alpha_context.Contract.t
+  * Alpha_context.Contract.t
+  * Alpha_context.Contract.t)
+  init
 
 val init_with_constants :
   Constants.parametric ->
diff --git a/src/proto_alpha/lib_protocol/test/helpers/contract_helpers.ml b/src/proto_alpha/lib_protocol/test/helpers/contract_helpers.ml
index 503b632e6ae7..82a78014a6c7 100644
--- a/src/proto_alpha/lib_protocol/test/helpers/contract_helpers.ml
+++ b/src/proto_alpha/lib_protocol/test/helpers/contract_helpers.ml
@@ -30,12 +30,7 @@ open Error_monad_operators
 (** Initializes 2 addresses to do only operations plus one that will be
     used to bake. *)
 let init () =
-  Context.init ~consensus_threshold:0 3 >|=? fun (b, contracts) ->
-  let (src0, src1, src2) =
-    match contracts with
-    | src0 :: src1 :: src2 :: _ -> (src0, src1, src2)
-    | _ -> assert false
-  in
+  Context.init3 ~consensus_threshold:0 () >|=? fun (b, (src0, src1, src2)) ->
   let baker =
     match Alpha_context.Contract.is_implicit src0 with
     | Some v -> v
diff --git a/src/proto_alpha/lib_protocol/test/helpers/liquidity_baking_machine.ml b/src/proto_alpha/lib_protocol/test/helpers/liquidity_baking_machine.ml
index 1d7d4716c72a..5459e68cfd61 100644
--- a/src/proto_alpha/lib_protocol/test/helpers/liquidity_baking_machine.ml
+++ b/src/proto_alpha/lib_protocol/test/helpers/liquidity_baking_machine.ml
@@ -60,7 +60,7 @@ open Alpha_context
           automatically.
        4. We introduce the [MACHINE_WITH_INIT] module type which is a
           superset of [MACHINE], extended with an [init] function
-          (analogous to {! Context.init}) to create an initial, mostly
+          (analogous to {! Context.init_n}) to create an initial, mostly
           blank state, and the [MachineBuilder.Make] functor that we
           can use to derive a machine with a [build] function.
        5. We construct the [ConcreteMachine], that allows to
@@ -387,7 +387,7 @@ let default_subsidy =
 
 let security_deposit = 640_000_000L
 
-(* When calling [Context.init] with a list of initial balances, the
+(* When calling [Context.init_n] with a list of initial balances, the
    sum of these balances should be equal to this constant. *)
 let total_xtz = 32_000_000_000_000L
 
@@ -859,7 +859,7 @@ module ConcreteBaseMachine :
   let init ~invariant ?subsidy accounts_balances =
     let liquidity_baking_subsidy = Option.map Tez.of_mutez_exn subsidy in
     let (n, initial_balances) = initial_xtz_repartition accounts_balances in
-    Context.init
+    Context.init_n
       n
       ~consensus_threshold:0
       ~initial_balances
@@ -871,6 +871,7 @@ module ConcreteBaseMachine :
       ~blocks_per_cycle:10_000l
       ~cycles_per_voting_period:1l
       ?liquidity_baking_subsidy
+      ()
     >>= function
     | (blk, holder :: accounts) ->
         let ctxt = Context.B blk in
diff --git a/src/proto_alpha/lib_protocol/test/helpers/sapling_helpers.ml b/src/proto_alpha/lib_protocol/test/helpers/sapling_helpers.ml
index b08dc98a604e..8339f0f73f9b 100644
--- a/src/proto_alpha/lib_protocol/test/helpers/sapling_helpers.ml
+++ b/src/proto_alpha/lib_protocol/test/helpers/sapling_helpers.ml
@@ -150,7 +150,7 @@ module Alpha_context_helpers = struct
   include Common
 
   let init () =
-    Context.init 1 >>=? fun (b, _) ->
+    Context.init1 () >>=? fun (b, _contract) ->
     Alpha_context.prepare
       b.context
       ~level:b.header.shell.level
diff --git a/src/proto_alpha/lib_protocol/test/helpers/tx_rollup_l2_helpers.ml b/src/proto_alpha/lib_protocol/test/helpers/tx_rollup_l2_helpers.ml
index c3869585dac8..496f781594cb 100644
--- a/src/proto_alpha/lib_protocol/test/helpers/tx_rollup_l2_helpers.ml
+++ b/src/proto_alpha/lib_protocol/test/helpers/tx_rollup_l2_helpers.ml
@@ -138,7 +138,7 @@ let gen_n_address n =
 let gen_n_ticket_hash n =
   let x =
     Lwt_main.run
-      ( Context.init n >>=? fun (_, contracts) ->
+      ( Context.init_n n () >>=? fun (_, contracts) ->
         let addressess = gen_n_address n in
         let tickets =
           List.map2
diff --git a/src/proto_alpha/lib_protocol/test/integration/consensus/test_baking.ml b/src/proto_alpha/lib_protocol/test/integration/consensus/test_baking.ml
index b978a4a24e82..cc083464c23c 100644
--- a/src/proto_alpha/lib_protocol/test/integration/consensus/test_baking.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/consensus/test_baking.ml
@@ -50,7 +50,7 @@ open Alpha_context
     - Randomize the number of blocks baked after the n cycles baked
       previously. *)
 let test_cycle () =
-  Context.init ~consensus_threshold:0 5 >>=? fun (b, _) ->
+  Context.init_n ~consensus_threshold:0 5 () >>=? fun (b, _contracts) ->
   Context.get_constants (B b) >>=? fun csts ->
   let blocks_per_cycle = csts.parametric.blocks_per_cycle in
   let pp fmt x = Format.fprintf fmt "%ld" x in
@@ -82,7 +82,7 @@ let wrap et = et >>= fun e -> Lwt.return (Environment.wrap_tzresult e)
 let test_bake_n_cycles n () =
   let open Block in
   let policy = By_round 0 in
-  Context.init ~consensus_threshold:0 1 >>=? fun (block, _contracts) ->
+  Context.init1 ~consensus_threshold:0 () >>=? fun (block, _contract) ->
   Block.bake_until_n_cycle_end ~policy n block >>=? fun _block -> return ()
 
 (** Check that, after one or two voting periods, the voting power of a baker is
@@ -91,7 +91,7 @@ let test_bake_n_cycles n () =
 let test_voting_power_cache () =
   let open Block in
   let policy = By_round 0 in
-  Context.init ~consensus_threshold:0 1 >>=? fun (genesis, _contracts) ->
+  Context.init1 ~consensus_threshold:0 () >>=? fun (genesis, _contract) ->
   Context.get_constants (B genesis) >>=? fun csts ->
   let blocks_per_voting_period =
     Int32.(
@@ -152,9 +152,8 @@ let test_voting_power_cache () =
 
 (** test that after baking, one gets the baking reward fixed portion. *)
 let test_basic_baking_reward () =
-  Context.init ~consensus_threshold:0 1 >>=? fun (genesis, contracts) ->
+  Context.init1 ~consensus_threshold:0 () >>=? fun (genesis, baker) ->
   Block.bake genesis >>=? fun b ->
-  let baker = WithExceptions.Option.get ~loc:__LOC__ @@ List.hd contracts in
   Context.Contract.pkh baker >>=? fun baker_pkh ->
   Context.Contract.balance (B b) baker >>=? fun bal ->
   Context.Delegate.current_frozen_deposits (B b) baker_pkh
@@ -189,7 +188,7 @@ let get_contract_for_pkh contracts pkh =
     [b2'] is build on top of [b1] by a different baker, using the same payload as
     [b2].  *)
 let test_rewards_block_and_payload_producer () =
-  Context.init ~consensus_threshold:1 10 >>=? fun (genesis, contracts) ->
+  Context.init_n ~consensus_threshold:1 10 () >>=? fun (genesis, contracts) ->
   Context.get_baker (B genesis) ~round:0 >>=? fun baker_b1 ->
   get_contract_for_pkh contracts baker_b1 >>=? fun baker_b1_contract ->
   Block.bake ~policy:(By_round 0) genesis >>=? fun b1 ->
@@ -303,7 +302,7 @@ let test_rewards_block_and_payload_producer () =
     - a delegate that has no active stake cannot bake.
 *)
 let test_enough_active_stake_to_bake ~has_active_stake () =
-  Context.init 1 >>=? fun (b_for_constants, _) ->
+  Context.init1 () >>=? fun (b_for_constants, _contract) ->
   Context.get_constants (B b_for_constants)
   >>=? fun Constants.{parametric = {tokens_per_roll; _}; _} ->
   let tpr = Tez.to_mutez tokens_per_roll in
@@ -312,11 +311,8 @@ let test_enough_active_stake_to_bake ~has_active_stake () =
      active balance is less or equal the staking balance (see
      [Delegate_storage.select_distribution_for_cycle]). *)
   let initial_bal1 = if has_active_stake then tpr else Int64.sub tpr 1L in
-  Context.init ~initial_balances:[initial_bal1; tpr] ~consensus_threshold:0 2
-  >>=? fun (b0, accounts) ->
-  let (account1, _account2) =
-    match accounts with a1 :: a2 :: _ -> (a1, a2) | _ -> assert false
-  in
+  Context.init2 ~initial_balances:[initial_bal1; tpr] ~consensus_threshold:0 ()
+  >>=? fun (b0, (account1, _account2)) ->
   Context.Contract.pkh account1 >>=? fun pkh1 ->
   Context.get_constants (B b0)
   >>=? fun Constants.{parametric = {baking_reward_fixed_portion; _}; _} ->
diff --git a/src/proto_alpha/lib_protocol/test/integration/consensus/test_deactivation.ml b/src/proto_alpha/lib_protocol/test/integration/consensus/test_deactivation.ml
index 7c5218e60587..2c9daffd2ef7 100644
--- a/src/proto_alpha/lib_protocol/test/integration/consensus/test_deactivation.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/consensus/test_deactivation.ml
@@ -39,8 +39,6 @@ open Protocol
 open Alpha_context
 open Test_tez
 
-let account_pair = function [a1; a2] -> (a1, a2) | _ -> assert false
-
 let wrap e = Lwt.return (Environment.wrap_tzresult e)
 
 (** Check that [Delegate.staking_balance] is the same as [Delegate.full_balance]
@@ -87,8 +85,7 @@ let check_no_stake ~loc (b : Block.t) (account : Account.t) =
     own balance, and that its staking rights are consistent
     (check_stake). *)
 let test_simple_staking_rights () =
-  Context.init 2 >>=? fun (b, accounts) ->
-  let (a1, _a2) = account_pair accounts in
+  Context.init2 () >>=? fun (b, (a1, _a2)) ->
   Context.Contract.balance (B b) a1 >>=? fun balance ->
   Context.Contract.pkh a1 >>=? fun delegate1 ->
   Context.Delegate.current_frozen_deposits (B b) delegate1
@@ -110,8 +107,7 @@ let test_simple_staking_rights () =
     equals to its balance. Then both accounts have consistent staking
     rights. *)
 let test_simple_staking_rights_after_baking () =
-  Context.init ~consensus_threshold:0 2 >>=? fun (b, accounts) ->
-  let (a1, a2) = account_pair accounts in
+  Context.init2 ~consensus_threshold:0 () >>=? fun (b, (a1, a2)) ->
   Context.Contract.manager (B b) a1 >>=? fun m1 ->
   Context.Contract.manager (B b) a2 >>=? fun m2 ->
   Block.bake_n ~policy:(By_account m2.pkh) 5 b >>=? fun b ->
@@ -130,8 +126,7 @@ let check_active_staking_balance ~loc ~deactivated b (m : Account.t) =
   if deactivated then check_no_stake ~loc b m else check_stake ~loc b m
 
 let run_until_deactivation () =
-  Context.init ~consensus_threshold:0 2 >>=? fun (b, accounts) ->
-  let (a1, a2) = account_pair accounts in
+  Context.init2 ~consensus_threshold:0 () >>=? fun (b, (a1, a2)) ->
   Context.Contract.balance (B b) a1 >>=? fun balance_start ->
   Context.Contract.manager (B b) a1 >>=? fun m1 ->
   Context.Contract.manager (B b) a2 >>=? fun m2 ->
@@ -297,8 +292,7 @@ let test_deactivation_then_empty_then_self_delegation_then_recredit () =
    be activated. Again, consistency for baking rights are preserved for the
    first and third accounts. *)
 let test_delegation () =
-  Context.init ~consensus_threshold:0 2 >>=? fun (b, accounts) ->
-  let (a1, a2) = account_pair accounts in
+  Context.init2 ~consensus_threshold:0 () >>=? fun (b, (a1, a2)) ->
   let m3 = Account.new_account () in
   Account.add_account m3 ;
   Context.Contract.manager (B b) a1 >>=? fun m1 ->
diff --git a/src/proto_alpha/lib_protocol/test/integration/consensus/test_delegation.ml b/src/proto_alpha/lib_protocol/test/integration/consensus/test_delegation.ml
index 2c65f914acbd..8696d98612e3 100644
--- a/src/proto_alpha/lib_protocol/test/integration/consensus/test_delegation.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/consensus/test_delegation.ml
@@ -71,23 +71,14 @@ let expect_delegate_already_active_error i op =
 
 (** Bootstrap contracts delegate to themselves. *)
 let bootstrap_manager_is_bootstrap_delegate () =
-  Context.init 1 >>=? fun (b, bootstrap_contracts) ->
-  let bootstrap0 =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.hd bootstrap_contracts
-  in
+  Context.init1 () >>=? fun (b, bootstrap0) ->
   Context.Contract.delegate (B b) bootstrap0 >>=? fun delegate0 ->
   Context.Contract.manager (B b) bootstrap0 >>=? fun manager0 ->
   Assert.equal_pkh ~loc:__LOC__ delegate0 manager0.pkh
 
 (** Bootstrap contracts cannot change their delegate. *)
 let bootstrap_delegate_cannot_change ~fee () =
-  Context.init 2 >>=? fun (b, bootstrap_contracts) ->
-  let bootstrap0 =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.nth bootstrap_contracts 0
-  in
-  let bootstrap1 =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.nth bootstrap_contracts 1
-  in
+  Context.init2 () >>=? fun (b, (bootstrap0, bootstrap1)) ->
   Context.Contract.pkh bootstrap0 >>=? fun pkh1 ->
   Incremental.begin_construction b ~policy:(Block.Excluding [pkh1])
   >>=? fun i ->
@@ -113,10 +104,7 @@ let bootstrap_delegate_cannot_change ~fee () =
 
 (** Bootstrap contracts cannot delete their delegation. *)
 let bootstrap_delegate_cannot_be_removed ~fee () =
-  Context.init 1 >>=? fun (b, bootstrap_contracts) ->
-  let bootstrap =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.hd bootstrap_contracts
-  in
+  Context.init1 () >>=? fun (b, bootstrap) ->
   Incremental.begin_construction b >>=? fun i ->
   Context.Contract.balance (I i) bootstrap >>=? fun balance ->
   Context.Contract.delegate (I i) bootstrap >>=? fun delegate ->
@@ -139,13 +127,7 @@ let bootstrap_delegate_cannot_be_removed ~fee () =
 (** Contracts not registered as delegate can change their
     delegation. *)
 let delegate_can_be_changed_from_unregistered_contract ~fee () =
-  Context.init 2 >>=? fun (b, bootstrap_contracts) ->
-  let bootstrap0 =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.hd bootstrap_contracts
-  in
-  let bootstrap1 =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.nth bootstrap_contracts 1
-  in
+  Context.init2 () >>=? fun (b, (bootstrap0, bootstrap1)) ->
   let unregistered_account = Account.new_account () in
   let unregistered_pkh = Account.(unregistered_account.pkh) in
   let unregistered = Contract.implicit_contract unregistered_pkh in
@@ -178,10 +160,7 @@ let delegate_can_be_changed_from_unregistered_contract ~fee () =
 (** Contracts not registered as delegate can delete their
     delegation. *)
 let delegate_can_be_removed_from_unregistered_contract ~fee () =
-  Context.init 1 >>=? fun (b, bootstrap_contracts) ->
-  let bootstrap =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.hd bootstrap_contracts
-  in
+  Context.init1 () >>=? fun (b, bootstrap) ->
   let unregistered_account = Account.new_account () in
   let unregistered_pkh = Account.(unregistered_account.pkh) in
   let unregistered = Contract.implicit_contract unregistered_pkh in
@@ -213,11 +192,8 @@ let delegate_can_be_removed_from_unregistered_contract ~fee () =
 
 (** Bootstrap keys are already registered as delegate keys. *)
 let bootstrap_manager_already_registered_delegate ~fee () =
-  Context.init 1 >>=? fun (b, bootstrap_contracts) ->
+  Context.init1 () >>=? fun (b, bootstrap) ->
   Incremental.begin_construction b >>=? fun i ->
-  let bootstrap =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.hd bootstrap_contracts
-  in
   Context.Contract.manager (I i) bootstrap >>=? fun manager ->
   let pkh = manager.pkh in
   let impl_contract = Contract.implicit_contract pkh in
@@ -239,11 +215,8 @@ let bootstrap_manager_already_registered_delegate ~fee () =
 (** Bootstrap manager can be set as delegate of an originated contract
     (through origination operation). *)
 let delegate_to_bootstrap_by_origination ~fee () =
-  Context.init 1 >>=? fun (b, bootstrap_contracts) ->
+  Context.init1 () >>=? fun (b, bootstrap) ->
   Incremental.begin_construction b >>=? fun i ->
-  let bootstrap =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.hd bootstrap_contracts
-  in
   Context.Contract.manager (I i) bootstrap >>=? fun manager ->
   Context.Contract.balance (I i) bootstrap >>=? fun balance ->
   (* originate a contract with bootstrap's manager as delegate *)
@@ -293,13 +266,13 @@ let delegate_to_bootstrap_by_origination ~fee () =
     Assert.balance_was_debited ~loc:__LOC__ (I i) bootstrap balance total_fee
 
 let undelegated_originated_bootstrap_contract () =
-  Context.init
-    1
+  Context.init1
     ~bootstrap_contracts:
       [
         Parameters.{delegate = None; amount = Tez.zero; script = Op.dummy_script};
       ]
-  >>=? fun (b, _) ->
+    ()
+  >>=? fun (b, _contract) ->
   Block.bake b >>=? fun b ->
   (* We know the address of the first originated bootstrap contract because we know the bootstrap origination nonce. This address corresponds to the first TF vesting contract on mainnnet. *)
   Lwt.return @@ Environment.wrap_tzresult
@@ -450,11 +423,8 @@ let expect_unregistered_key pkh = function
     (unregistered key), and the fees are still debited. Using RPCs, we
     verify the contract has not been originated. *)
 let test_unregistered_delegate_key_init_origination ~fee () =
-  Context.init 1 >>=? fun (b, bootstrap_contracts) ->
+  Context.init1 () >>=? fun (b, bootstrap) ->
   Incremental.begin_construction b >>=? fun i ->
-  let bootstrap =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.hd bootstrap_contracts
-  in
   let unregistered_account = Account.new_account () in
   let unregistered_pkh = Account.(unregistered_account.pkh) in
   (* origination with delegate argument *)
@@ -492,11 +462,8 @@ let test_unregistered_delegate_key_init_origination ~fee () =
     [Balance_too_low] is raised. Otherwise, fees are still debited. The
     implicit contract has no delegate. *)
 let test_unregistered_delegate_key_init_delegation ~fee () =
-  Context.init 1 >>=? fun (b, bootstrap_contracts) ->
+  Context.init1 () >>=? fun (b, bootstrap) ->
   Incremental.begin_construction b >>=? fun i ->
-  let bootstrap =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.hd bootstrap_contracts
-  in
   let unregistered_account = Account.new_account () in
   let unregistered_pkh = Account.(unregistered_account.pkh) in
   let impl_contract = Contract.implicit_contract unregistered_pkh in
@@ -532,11 +499,8 @@ let test_unregistered_delegate_key_init_delegation ~fee () =
     raised. Otherwise, fees are not debited and the implicit contract
     delegate remains unchanged. *)
 let test_unregistered_delegate_key_switch_delegation ~fee () =
-  Context.init 1 >>=? fun (b, bootstrap_contracts) ->
+  Context.init1 () >>=? fun (b, bootstrap) ->
   Incremental.begin_construction b >>=? fun i ->
-  let bootstrap =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.hd bootstrap_contracts
-  in
   let bootstrap_pkh =
     Contract.is_implicit bootstrap |> WithExceptions.Option.get ~loc:__LOC__
   in
@@ -577,11 +541,8 @@ let test_unregistered_delegate_key_switch_delegation ~fee () =
 (** Same as [unregistered_delegate_key_init_origination] and credits
     [amount], no self-delegation. *)
 let test_unregistered_delegate_key_init_origination_credit ~fee ~amount () =
-  Context.init 1 >>=? fun (b, bootstrap_contracts) ->
+  Context.init1 () >>=? fun (b, bootstrap) ->
   Incremental.begin_construction b >>=? fun i ->
-  let bootstrap =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.hd bootstrap_contracts
-  in
   let unregistered_account = Account.new_account () in
   let unregistered_pkh = Account.(unregistered_account.pkh) in
   let impl_contract = Contract.implicit_contract unregistered_pkh in
@@ -617,11 +578,8 @@ let test_unregistered_delegate_key_init_origination_credit ~fee ~amount () =
 (** Same as [unregistered_delegate_key_init_delegation] and credits
     the amount [amount] of the implicit contract. *)
 let test_unregistered_delegate_key_init_delegation_credit ~fee ~amount () =
-  Context.init 1 >>=? fun (b, bootstrap_contracts) ->
+  Context.init1 () >>=? fun (b, bootstrap) ->
   Incremental.begin_construction b >>=? fun i ->
-  let bootstrap =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.hd bootstrap_contracts
-  in
   let unregistered_account = Account.new_account () in
   let unregistered_pkh = Account.(unregistered_account.pkh) in
   let impl_contract = Contract.implicit_contract unregistered_pkh in
@@ -660,11 +618,8 @@ let test_unregistered_delegate_key_init_delegation_credit ~fee ~amount () =
 (** Same as in [unregistered_delegate_key_switch_delegation] and
     credits the amount [amount] to the implicit contract. *)
 let test_unregistered_delegate_key_switch_delegation_credit ~fee ~amount () =
-  Context.init 1 >>=? fun (b, bootstrap_contracts) ->
+  Context.init1 () >>=? fun (b, bootstrap) ->
   Incremental.begin_construction b >>=? fun i ->
-  let bootstrap =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.hd bootstrap_contracts
-  in
   let bootstrap_pkh =
     Contract.is_implicit bootstrap |> WithExceptions.Option.get ~loc:__LOC__
   in
@@ -712,11 +667,8 @@ let test_unregistered_delegate_key_switch_delegation_credit ~fee ~amount () =
     no self-delegation. *)
 let test_unregistered_delegate_key_init_origination_credit_debit ~fee ~amount ()
     =
-  Context.init 1 >>=? fun (b, bootstrap_contracts) ->
+  Context.init1 () >>=? fun (b, bootstrap) ->
   Incremental.begin_construction b >>=? fun i ->
-  let bootstrap =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.hd bootstrap_contracts
-  in
   let unregistered_account = Account.new_account () in
   let unregistered_pkh = Account.(unregistered_account.pkh) in
   let impl_contract = Contract.implicit_contract unregistered_pkh in
@@ -757,11 +709,8 @@ let test_unregistered_delegate_key_init_origination_credit_debit ~fee ~amount ()
     then debits the amount [amount] to the implicit contract. *)
 let test_unregistered_delegate_key_init_delegation_credit_debit ~amount ~fee ()
     =
-  Context.init 1 >>=? fun (b, bootstrap_contracts) ->
+  Context.init1 () >>=? fun (b, bootstrap) ->
   Incremental.begin_construction b >>=? fun i ->
-  let bootstrap =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.hd bootstrap_contracts
-  in
   let unregistered_account = Account.new_account () in
   let unregistered_pkh = Account.(unregistered_account.pkh) in
   let impl_contract = Contract.implicit_contract unregistered_pkh in
@@ -805,11 +754,8 @@ let test_unregistered_delegate_key_init_delegation_credit_debit ~amount ~fee ()
     credits then debits the amount [amount] to the implicit contract. *)
 let test_unregistered_delegate_key_switch_delegation_credit_debit ~fee ~amount
     () =
-  Context.init 1 >>=? fun (b, bootstrap_contracts) ->
+  Context.init1 () >>=? fun (b, bootstrap) ->
   Incremental.begin_construction b >>=? fun i ->
-  let bootstrap =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.hd bootstrap_contracts
-  in
   let bootstrap_pkh =
     Contract.is_implicit bootstrap |> WithExceptions.Option.get ~loc:__LOC__
   in
@@ -860,7 +806,7 @@ let test_unregistered_delegate_key_switch_delegation_credit_debit ~fee ~amount
 
 (** Self-delegation with zero-balance contract should fail. *)
 let test_failed_self_delegation_no_transaction () =
-  Context.init 1 >>=? fun (b, _) ->
+  Context.init1 () >>=? fun (b, _contract) ->
   Incremental.begin_construction b >>=? fun i ->
   let account = Account.new_account () in
   let unregistered_pkh = Account.(account.pkh) in
@@ -878,11 +824,8 @@ let test_failed_self_delegation_no_transaction () =
     is emptied). Self-delegation fails. *)
 let test_failed_self_delegation_emptied_implicit_contract amount () =
   (* create an implicit contract *)
-  Context.init 1 >>=? fun (b, bootstrap_contracts) ->
+  Context.init1 () >>=? fun (b, bootstrap) ->
   Incremental.begin_construction b >>=? fun i ->
-  let bootstrap =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.hd bootstrap_contracts
-  in
   let account = Account.new_account () in
   let unregistered_pkh = Account.(account.pkh) in
   let impl_contract = Contract.implicit_contract unregistered_pkh in
@@ -906,11 +849,8 @@ let test_failed_self_delegation_emptied_implicit_contract amount () =
     tz, then it is delegated. The operation of debit of [amount] tz
     should fail as the contract is already delegated. *)
 let test_emptying_delegated_implicit_contract_fails amount () =
-  Context.init 1 >>=? fun (b, bootstrap_contracts) ->
+  Context.init1 () >>=? fun (b, bootstrap) ->
   Incremental.begin_construction b >>=? fun i ->
-  let bootstrap =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.hd bootstrap_contracts
-  in
   Context.Contract.manager (I i) bootstrap >>=? fun bootstrap_manager ->
   let account = Account.new_account () in
   let unregistered_pkh = Account.(account.pkh) in
@@ -944,11 +884,8 @@ let test_emptying_delegated_implicit_contract_fails amount () =
     self-delegated. *)
 let test_valid_delegate_registration_init_delegation_credit amount () =
   (* create an implicit contract *)
-  Context.init 1 >>=? fun (b, bootstrap_contracts) ->
+  Context.init1 () >>=? fun (b, bootstrap) ->
   Incremental.begin_construction b >>=? fun i ->
-  let bootstrap =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.hd bootstrap_contracts
-  in
   let delegate_account = Account.new_account () in
   let delegate_pkh = Account.(delegate_account.pkh) in
   let impl_contract = Contract.implicit_contract delegate_pkh in
@@ -990,11 +927,8 @@ let test_valid_delegate_registration_init_delegation_credit amount () =
     contract. *)
 let test_valid_delegate_registration_switch_delegation_credit amount () =
   (* create an implicit contract *)
-  Context.init 1 >>=? fun (b, bootstrap_contracts) ->
+  Context.init1 () >>=? fun (b, bootstrap) ->
   Incremental.begin_construction b >>=? fun i ->
-  let bootstrap =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.hd bootstrap_contracts
-  in
   let delegate_account = Account.new_account () in
   let delegate_pkh = Account.(delegate_account.pkh) in
   let impl_contract = Contract.implicit_contract delegate_pkh in
@@ -1034,11 +968,8 @@ let test_valid_delegate_registration_switch_delegation_credit amount () =
 (** Create an implicit contract. *)
 let test_valid_delegate_registration_init_delegation_credit_debit amount () =
   (* create an implicit contract *)
-  Context.init 1 >>=? fun (b, bootstrap_contracts) ->
+  Context.init1 () >>=? fun (b, bootstrap) ->
   Incremental.begin_construction b >>=? fun i ->
-  let bootstrap =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.hd bootstrap_contracts
-  in
   let delegate_account = Account.new_account () in
   let delegate_pkh = Account.(delegate_account.pkh) in
   let impl_contract = Contract.implicit_contract delegate_pkh in
@@ -1091,11 +1022,8 @@ let test_valid_delegate_registration_init_delegation_credit_debit amount () =
     be re-delegated to the latter contract. *)
 let test_valid_delegate_registration_switch_delegation_credit_debit amount () =
   (* create an implicit contract *)
-  Context.init 1 >>=? fun (b, bootstrap_contracts) ->
+  Context.init1 () >>=? fun (b, bootstrap) ->
   Incremental.begin_construction b >>=? fun i ->
-  let bootstrap =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.hd bootstrap_contracts
-  in
   let delegate_account = Account.new_account () in
   let delegate_pkh = Account.(delegate_account.pkh) in
   let impl_contract = Contract.implicit_contract delegate_pkh in
@@ -1145,11 +1073,8 @@ let test_valid_delegate_registration_switch_delegation_credit_debit amount () =
 (** Second self-delegation should fail with implicit contract with
     some credit. *)
 let test_double_registration () =
-  Context.init 1 >>=? fun (b, bootstrap_contracts) ->
+  Context.init1 () >>=? fun (b, bootstrap) ->
   Incremental.begin_construction b >>=? fun i ->
-  let bootstrap =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.hd bootstrap_contracts
-  in
   let account = Account.new_account () in
   let pkh = Account.(account.pkh) in
   let impl_contract = Contract.implicit_contract pkh in
@@ -1168,11 +1093,8 @@ let test_double_registration () =
 (** Second self-delegation should fail with implicit contract emptied
     after first self-delegation. *)
 let test_double_registration_when_empty () =
-  Context.init 1 >>=? fun (b, bootstrap_contracts) ->
+  Context.init1 () >>=? fun (b, bootstrap) ->
   Incremental.begin_construction b >>=? fun i ->
-  let bootstrap =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.hd bootstrap_contracts
-  in
   let account = Account.new_account () in
   let pkh = Account.(account.pkh) in
   let impl_contract = Contract.implicit_contract pkh in
@@ -1196,11 +1118,8 @@ let test_double_registration_when_empty () =
 (** Second self-delegation should fail with implicit contract emptied
     then credited back after first self-delegation. *)
 let test_double_registration_when_recredited () =
-  Context.init 1 >>=? fun (b, bootstrap_contracts) ->
+  Context.init1 () >>=? fun (b, bootstrap) ->
   Incremental.begin_construction b >>=? fun i ->
-  let bootstrap =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.hd bootstrap_contracts
-  in
   let account = Account.new_account () in
   let pkh = Account.(account.pkh) in
   let impl_contract = Contract.implicit_contract pkh in
@@ -1228,11 +1147,8 @@ let test_double_registration_when_recredited () =
 
 (** Self-delegation on unrevealed contract. *)
 let test_unregistered_and_unrevealed_self_delegate_key_init_delegation ~fee () =
-  Context.init 1 >>=? fun (b, bootstrap_contracts) ->
+  Context.init1 () >>=? fun (b, bootstrap) ->
   Incremental.begin_construction b >>=? fun i ->
-  let bootstrap =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.hd bootstrap_contracts
-  in
   let {Account.pkh; _} = Account.new_account () in
   let {Account.pkh = delegate_pkh; _} = Account.new_account () in
   let contract = Alpha_context.Contract.implicit_contract pkh in
@@ -1252,11 +1168,8 @@ let test_unregistered_and_unrevealed_self_delegate_key_init_delegation ~fee () =
 
 (** Self-delegation on revealed but not registered contract. *)
 let test_unregistered_and_revealed_self_delegate_key_init_delegation ~fee () =
-  Context.init 1 >>=? fun (b, bootstrap_contracts) ->
+  Context.init1 () >>=? fun (b, bootstrap) ->
   Incremental.begin_construction b >>=? fun i ->
-  let bootstrap =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.hd bootstrap_contracts
-  in
   let {Account.pkh; pk; _} = Account.new_account () in
   let {Account.pkh = delegate_pkh; _} = Account.new_account () in
   let contract = Alpha_context.Contract.implicit_contract pkh in
@@ -1278,11 +1191,8 @@ let test_unregistered_and_revealed_self_delegate_key_init_delegation ~fee () =
 
 (** Self-delegation emptying a fresh contract. *)
 let test_self_delegation_emptying_contract () =
-  Context.init 1 >>=? fun (b, bootstrap_contracts) ->
+  Context.init1 () >>=? fun (b, bootstrap) ->
   Incremental.begin_construction b >>=? fun i ->
-  let bootstrap =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.hd bootstrap_contracts
-  in
   let {Account.pkh; pk; _} = Account.new_account () in
   let {Account.pkh = delegate_pkh; _} = Account.new_account () in
   let contract = Alpha_context.Contract.implicit_contract pkh in
@@ -1306,11 +1216,8 @@ let test_self_delegation_emptying_contract () =
 
 (** Self-delegation on revealed and registered contract. *)
 let test_registered_self_delegate_key_init_delegation () =
-  Context.init 1 >>=? fun (b, bootstrap_contracts) ->
+  Context.init1 () >>=? fun (b, bootstrap) ->
   Incremental.begin_construction b >>=? fun i ->
-  let bootstrap =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.hd bootstrap_contracts
-  in
   let {Account.pkh; _} = Account.new_account () in
   let {Account.pkh = delegate_pkh; pk = delegate_pk; _} =
     Account.new_account ()
diff --git a/src/proto_alpha/lib_protocol/test/integration/consensus/test_double_baking.ml b/src/proto_alpha/lib_protocol/test/integration/consensus/test_double_baking.ml
index 76ea9a0efb4d..5aacf11ca926 100644
--- a/src/proto_alpha/lib_protocol/test/integration/consensus/test_double_baking.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/consensus/test_double_baking.ml
@@ -43,10 +43,7 @@ open Alpha_context
 
 (** Bake two block at the same level using the same policy (i.e. same
     baker). *)
-let block_fork ?policy contracts b =
-  let (contract_a, contract_b) =
-    match contracts with x :: y :: _ -> (x, y) | _ -> assert false
-  in
+let block_fork ?policy (contract_a, contract_b) b =
   Op.transaction (B b) contract_a contract_b Alpha_context.Tez.one_cent
   >>=? fun operation ->
   Block.bake ?policy ~operation b >>=? fun blk_a ->
@@ -71,7 +68,7 @@ let double_baking ctxt ?(correct_order = true) bh1 bh2 =
 (** Simple scenario where two blocks are baked by a same baker and
     exposed by a double baking evidence operation. *)
 let test_valid_double_baking_evidence () =
-  Context.init ~consensus_threshold:0 2 >>=? fun (genesis, contracts) ->
+  Context.init2 ~consensus_threshold:0 () >>=? fun (genesis, contracts) ->
   Context.get_constants (B genesis)
   >>=? fun Constants.{parametric = {double_baking_punishment; _}; _} ->
   Context.get_first_different_bakers (B genesis) >>=? fun (baker1, baker2) ->
@@ -111,7 +108,7 @@ let double_endorsement ctxt ?(correct_order = true) op1 op2 =
   Op.double_endorsement ctxt e1 e2
 
 let test_valid_double_baking_followed_by_double_endorsing () =
-  Context.init ~consensus_threshold:0 2 >>=? fun (genesis, contracts) ->
+  Context.init2 ~consensus_threshold:0 () >>=? fun (genesis, contracts) ->
   Context.get_first_different_bakers (B genesis) >>=? fun (baker1, baker2) ->
   Block.bake genesis >>=? fun b ->
   Context.Delegate.current_frozen_deposits (B b) baker1
@@ -162,7 +159,7 @@ let block_fork_diff b =
   Block.bake ~policy:(By_account baker_2) b >|=? fun blk_b -> (blk_a, blk_b)
 
 let test_valid_double_endorsing_followed_by_double_baking () =
-  Context.init ~consensus_threshold:0 2 >>=? fun (genesis, contracts) ->
+  Context.init2 ~consensus_threshold:0 () >>=? fun (genesis, contracts) ->
   Context.get_first_different_bakers (B genesis) >>=? fun (baker1, baker2) ->
   block_fork_diff genesis >>=? fun (blk_1, blk_2) ->
   Context.Delegate.current_frozen_deposits (B genesis) baker1
@@ -213,7 +210,7 @@ let test_valid_double_endorsing_followed_by_double_baking () =
    baking evidence (and not the block producer, if different) receives
    the reward. *)
 let test_payload_producer_gets_evidence_rewards () =
-  Context.init ~consensus_threshold:0 10 >>=? fun (genesis, contracts) ->
+  Context.init_n ~consensus_threshold:0 10 () >>=? fun (genesis, contracts) ->
   Context.get_constants (B genesis)
   >>=? fun Constants.
              {
@@ -222,7 +219,10 @@ let test_payload_producer_gets_evidence_rewards () =
                _;
              } ->
   Context.get_first_different_bakers (B genesis) >>=? fun (baker1, baker2) ->
-  block_fork ~policy:(By_account baker1) contracts genesis >>=? fun (b1, b2) ->
+  let c1_c2 =
+    match contracts with c1 :: c2 :: _ -> (c1, c2) | _ -> assert false
+  in
+  block_fork ~policy:(By_account baker1) c1_c2 genesis >>=? fun (b1, b2) ->
   double_baking (B b1) b1.header b2.header |> fun db_evidence ->
   Block.bake ~policy:(By_account baker2) ~operation:db_evidence b1
   >>=? fun b_with_evidence ->
@@ -287,7 +287,7 @@ let test_payload_producer_gets_evidence_rewards () =
 (** Check that a double baking operation fails if it exposes the same two
     blocks. *)
 let test_same_blocks () =
-  Context.init 2 >>=? fun (b, _contracts) ->
+  Context.init2 () >>=? fun (b, _contracts) ->
   Block.bake b >>=? fun ba ->
   double_baking (B ba) ba.header ba.header |> fun operation ->
   Block.bake ~operation ba >>= fun res ->
@@ -296,7 +296,7 @@ let test_same_blocks () =
 (** Check that an double baking operation that is invalid due to
    incorrect ordering of the block headers fails. *)
 let test_incorrect_order () =
-  Context.init ~consensus_threshold:0 2 >>=? fun (genesis, contracts) ->
+  Context.init2 ~consensus_threshold:0 () >>=? fun (genesis, contracts) ->
   block_fork ~policy:(By_round 0) contracts genesis >>=? fun (blk_a, blk_b) ->
   double_baking (B genesis) ~correct_order:false blk_a.header blk_b.header
   |> fun operation ->
@@ -306,7 +306,7 @@ let test_incorrect_order () =
 (** Check that a double baking operation exposing two blocks with
     different levels fails. *)
 let test_different_levels () =
-  Context.init ~consensus_threshold:0 2 >>=? fun (b, contracts) ->
+  Context.init2 ~consensus_threshold:0 () >>=? fun (b, contracts) ->
   block_fork ~policy:(By_round 0) contracts b >>=? fun (blk_a, blk_b) ->
   Block.bake blk_b >>=? fun blk_b_2 ->
   double_baking (B blk_a) blk_a.header blk_b_2.header |> fun operation ->
@@ -316,7 +316,7 @@ let test_different_levels () =
 (** Check that a double baking operation exposing two yet-to-be-baked
     blocks fails. *)
 let test_too_early_double_baking_evidence () =
-  Context.init ~consensus_threshold:0 2 >>=? fun (genesis, contracts) ->
+  Context.init2 ~consensus_threshold:0 () >>=? fun (genesis, contracts) ->
   Block.bake_until_cycle_end genesis >>=? fun b ->
   block_fork ~policy:(By_round 0) contracts b >>=? fun (blk_a, blk_b) ->
   double_baking (B b) blk_a.header blk_b.header |> fun operation ->
@@ -326,7 +326,7 @@ let test_too_early_double_baking_evidence () =
 (** Check that after [max_slashing_period * blocks_per_cycle + 1] blocks -- corresponding to 2 cycles
    --, it is not possible to create a double baking operation anymore. *)
 let test_too_late_double_baking_evidence () =
-  Context.init ~consensus_threshold:0 2 >>=? fun (b, contracts) ->
+  Context.init2 ~consensus_threshold:0 () >>=? fun (b, contracts) ->
   Context.get_constants (B b)
   >>=? fun Constants.{parametric = {max_slashing_period; _}; _} ->
   block_fork ~policy:(By_round 0) contracts b >>=? fun (blk_a, blk_b) ->
@@ -339,7 +339,7 @@ let test_too_late_double_baking_evidence () =
    -- corresponding to 2 cycles --, it is still possible to create a
    double baking operation. *)
 let test_just_in_time_double_baking_evidence () =
-  Context.init ~consensus_threshold:0 2 >>=? fun (b, contracts) ->
+  Context.init2 ~consensus_threshold:0 () >>=? fun (b, contracts) ->
   Context.get_constants (B b)
   >>=? fun Constants.{parametric = {blocks_per_cycle; _}; _} ->
   block_fork ~policy:(By_round 0) contracts b >>=? fun (blk_a, blk_b) ->
@@ -353,7 +353,7 @@ let test_just_in_time_double_baking_evidence () =
 (** Check that an invalid double baking evidence that exposes two
     block baking with same level made by different bakers fails. *)
 let test_different_delegates () =
-  Context.init 2 >>=? fun (b, _) ->
+  Context.init2 () >>=? fun (b, _contracts) ->
   Context.get_first_different_bakers (B b) >>=? fun (baker_1, baker_2) ->
   Block.bake ~policy:(By_account baker_1) b >>=? fun blk_a ->
   Block.bake ~policy:(By_account baker_2) b >>=? fun blk_b ->
@@ -382,7 +382,7 @@ let test_wrong_signer () =
     >>=? fun header ->
     Block.Forge.set_baker baker_2 header |> Block.Forge.sign_header
   in
-  Context.init 2 >>=? fun (b, _) ->
+  Context.init2 () >>=? fun (b, _contracts) ->
   Context.get_first_different_bakers (B b) >>=? fun (baker_1, baker_2) ->
   Block.bake ~policy:(By_account baker_1) b >>=? fun blk_a ->
   let ts = Timestamp.of_seconds_string (Int64.to_string 10L) in
@@ -397,8 +397,8 @@ let test_wrong_signer () =
 (** an evidence can only be accepted once (this also means that the
    same evidence doesn't lead to slashing the offender twice) *)
 let test_double_evidence () =
-  Context.init ~consensus_threshold:0 3 >>=? fun (blk, contracts) ->
-  block_fork contracts blk >>=? fun (blk_a, blk_b) ->
+  Context.init3 ~consensus_threshold:0 () >>=? fun (blk, (c1, c2, _c3)) ->
+  block_fork (c1, c2) blk >>=? fun (blk_a, blk_b) ->
   Block.bake_until_cycle_end blk_a >>=? fun blk ->
   double_baking (B blk) blk_a.header blk_b.header |> fun evidence ->
   Block.bake ~operation:evidence blk >>=? fun blk ->
diff --git a/src/proto_alpha/lib_protocol/test/integration/consensus/test_double_endorsement.ml b/src/proto_alpha/lib_protocol/test/integration/consensus/test_double_endorsement.ml
index f4c22ef47f08..56a50dea5829 100644
--- a/src/proto_alpha/lib_protocol/test/integration/consensus/test_double_endorsement.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/consensus/test_double_endorsement.ml
@@ -87,7 +87,7 @@ let double_endorsement ctxt ?(correct_order = true) op1 op2 =
     delegate and exposed by a double_endorsement operation. Also verify
     that punishment is operated. *)
 let test_valid_double_endorsement_evidence () =
-  Context.init ~consensus_threshold:0 2 >>=? fun (genesis, _) ->
+  Context.init2 ~consensus_threshold:0 () >>=? fun (genesis, _contracts) ->
   block_fork genesis >>=? fun (blk_1, blk_2) ->
   (* from blk_1 we bake blk_a and from blk_2 we bake blk_b so that
      the same delegate endorses blk_a and blk_b and these 2 form
@@ -145,7 +145,7 @@ let test_valid_double_endorsement_evidence () =
 (** Say a delegate double-endorses twice and say the 2 evidences are timely
    included. Then the delegate can no longer bake. *)
 let test_two_double_endorsement_evidences_leadsto_no_bake () =
-  Context.init ~consensus_threshold:0 2 >>=? fun (genesis, _) ->
+  Context.init2 ~consensus_threshold:0 () >>=? fun (genesis, _contracts) ->
   block_fork genesis >>=? fun (blk_1, blk_2) ->
   Block.bake blk_1 >>=? fun blk_a ->
   Block.bake blk_2 >>=? fun blk_b ->
@@ -183,7 +183,7 @@ let test_two_double_endorsement_evidences_leadsto_no_bake () =
 (** Check that an invalid double endorsement operation that exposes a
       valid endorsement fails. *)
 let test_invalid_double_endorsement () =
-  Context.init ~consensus_threshold:0 10 >>=? fun (genesis, _) ->
+  Context.init_n ~consensus_threshold:0 10 () >>=? fun (genesis, _contracts) ->
   Block.bake genesis >>=? fun b ->
   Op.endorsement ~endorsed_block:b (B genesis) () >>=? fun endorsement ->
   Block.bake ~operation:(Operation.pack endorsement) b >>=? fun b ->
@@ -194,7 +194,7 @@ let test_invalid_double_endorsement () =
 (** Check that an double endorsement operation that is invalid due to
    incorrect ordering of the endorsements fails. *)
 let test_invalid_double_endorsement_variant () =
-  Context.init ~consensus_threshold:0 2 >>=? fun (genesis, _) ->
+  Context.init2 ~consensus_threshold:0 () >>=? fun (genesis, _contracts) ->
   Block.bake_until_cycle_end genesis >>=? fun b ->
   block_fork b >>=? fun (blk_1, blk_2) ->
   Block.bake blk_1 >>=? fun blk_a ->
@@ -212,7 +212,7 @@ let test_invalid_double_endorsement_variant () =
 
 (** Check that a future-cycle double endorsement fails. *)
 let test_too_early_double_endorsement_evidence () =
-  Context.init ~consensus_threshold:0 2 >>=? fun (genesis, _) ->
+  Context.init2 ~consensus_threshold:0 () >>=? fun (genesis, _contracts) ->
   Block.bake_until_cycle_end genesis >>=? fun b ->
   block_fork b >>=? fun (blk_1, blk_2) ->
   Block.bake blk_1 >>=? fun blk_a ->
@@ -226,7 +226,7 @@ let test_too_early_double_endorsement_evidence () =
 (** Check that after [max_slashing_period * blocks_per_cycle + 1], it is not possible
     to create a double_endorsement anymore. *)
 let test_too_late_double_endorsement_evidence () =
-  Context.init ~consensus_threshold:0 2 >>=? fun (genesis, _) ->
+  Context.init2 ~consensus_threshold:0 () >>=? fun (genesis, _contracts) ->
   Context.get_constants (B genesis)
   >>=? fun Constants.
              {parametric = {max_slashing_period; blocks_per_cycle; _}; _} ->
@@ -244,7 +244,7 @@ let test_too_late_double_endorsement_evidence () =
 (** Check that an invalid double endorsement evidence that exposes two
     endorsements made by two different endorsers fails. *)
 let test_different_delegates () =
-  Context.init ~consensus_threshold:0 2 >>=? fun (genesis, _) ->
+  Context.init2 ~consensus_threshold:0 () >>=? fun (genesis, _contracts) ->
   Block.bake genesis >>=? fun genesis ->
   block_fork genesis >>=? fun (blk_1, blk_2) ->
   Block.bake blk_1 >>=? fun blk_a ->
@@ -277,7 +277,7 @@ let test_different_delegates () =
 (** Check that a double endorsement evidence that exposes a ill-formed
     endorsement fails. *)
 let test_wrong_delegate () =
-  Context.init ~consensus_threshold:0 2 >>=? fun (genesis, _contracts) ->
+  Context.init2 ~consensus_threshold:0 () >>=? fun (genesis, _contracts) ->
   block_fork genesis >>=? fun (blk_1, blk_2) ->
   Block.bake blk_1 >>=? fun blk_a ->
   Block.bake blk_2 >>=? fun blk_b ->
diff --git a/src/proto_alpha/lib_protocol/test/integration/consensus/test_double_preendorsement.ml b/src/proto_alpha/lib_protocol/test/integration/consensus/test_double_preendorsement.ml
index 047a1b79dc74..810c9d4e810c 100644
--- a/src/proto_alpha/lib_protocol/test/integration/consensus/test_double_preendorsement.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/consensus/test_double_preendorsement.ml
@@ -69,7 +69,8 @@ end = struct
       ?(include_endorsement = false) ?(block_round = 0)
       ?(mk_evidence = fun ctxt p1 p2 -> Op.double_preendorsement ctxt p1 p2)
       ~loc () =
-    Context.init ~consensus_threshold:0 10 >>=? fun (genesis, _) ->
+    Context.init_n ~consensus_threshold:0 10 ()
+    >>=? fun (genesis, _contracts) ->
     bake genesis >>=? fun b1 ->
     bake ~policy:(By_round 0) b1 >>=? fun b2_A ->
     Op.endorsement ~endorsed_block:b1 (B genesis) () >>=? fun e ->
@@ -81,7 +82,7 @@ end = struct
     bake b1 ~operations:[op] >>= fun res -> invalid_denunciation loc res
 
   let max_slashing_period () =
-    Context.init ~consensus_threshold:0 1 >>=? fun (genesis, _) ->
+    Context.init1 ~consensus_threshold:0 () >>=? fun (genesis, _contract) ->
     Context.get_constants (B genesis)
     >>=? fun {parametric = {max_slashing_period; blocks_per_cycle; _}; _} ->
     return (max_slashing_period * Int32.to_int blocks_per_cycle)
@@ -172,7 +173,7 @@ end = struct
       ?(pick_endorsers =
         fun ctxt -> pick_endorsers ctxt >>=? fun (a, _b) -> return (a, a)) ~loc
       () =
-    Context.init ~consensus_threshold:0 10 >>=? fun (genesis, contracts) ->
+    Context.init_n ~consensus_threshold:0 10 () >>=? fun (genesis, contracts) ->
     let addr =
       match List.hd contracts with None -> assert false | Some e -> e
     in
diff --git a/src/proto_alpha/lib_protocol/test/integration/consensus/test_endorsement.ml b/src/proto_alpha/lib_protocol/test/integration/consensus/test_endorsement.ml
index 06a082b54e3c..292e00945721 100644
--- a/src/proto_alpha/lib_protocol/test/integration/consensus/test_endorsement.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/consensus/test_endorsement.ml
@@ -38,7 +38,7 @@ open Protocol
 open Alpha_context
 
 let init_genesis ?policy () =
-  Context.init ~consensus_threshold:0 5 >>=? fun (genesis, _) ->
+  Context.init_n ~consensus_threshold:0 5 () >>=? fun (genesis, _contracts) ->
   Block.bake ?policy genesis >>=? fun b -> return (genesis, b)
 
 (** inject an endorsement and return the block with the endorsement and its
@@ -62,7 +62,7 @@ let test_simple_endorsement () =
 
 (** Apply an endorsement with a negative slot. *)
 let test_negative_slot () =
-  Context.init 5 >>=? fun (genesis, _) ->
+  Context.init_n 5 () >>=? fun (genesis, _contracts) ->
   Block.bake genesis >>=? fun b ->
   Context.get_endorser (B b) >>=? fun (delegate, _slots) ->
   Lwt.catch
@@ -80,7 +80,7 @@ let test_negative_slot () =
 (** Apply an endorsement with a non-normalized slot (that is, not the smallest
    possible). *)
 let test_non_normalized_slot () =
-  Context.init 5 >>=? fun (genesis, _) ->
+  Context.init_n 5 () >>=? fun (genesis, _contracts) ->
   Block.bake genesis >>=? fun b ->
   Context.get_endorsers (B b) >>=? fun endorsers_list ->
   (* find an endorsers with more than 1 slot *)
@@ -312,7 +312,7 @@ let test_endorsement_threshold ~sufficient_threshold () =
      about 1 slot so we can get closer to the limit of [consensus_threshold]: we
      check that a block with endorsing power [consensus_threshold - 1] won't be
      baked. *)
-  Context.init 10 >>=? fun (genesis, _contracts) ->
+  Context.init_n 10 () >>=? fun (genesis, _contracts) ->
   Block.bake genesis >>=? fun b ->
   Context.get_constants (B b)
   >>=? fun {parametric = {consensus_threshold; _}; _} ->
@@ -362,7 +362,7 @@ let test_fitness_gap () =
   Assert.equal_int32 ~loc:__LOC__ level_diff 1l
 
 let test_preendorsement_endorsement_same_level () =
-  Context.init ~consensus_threshold:0 1 >>=? fun (genesis, _) ->
+  Context.init1 ~consensus_threshold:0 () >>=? fun (genesis, _contract) ->
   Block.bake genesis >>=? fun b1 ->
   Incremental.begin_construction ~mempool_mode:true ~policy:(By_round 2) b1
   >>=? fun i ->
@@ -376,7 +376,7 @@ let test_preendorsement_endorsement_same_level () =
 (** Test for endorsement injection with wrong slot in mempool mode. This
     test is expected to fail *)
 let test_wrong_endorsement_slot_in_mempool_mode () =
-  Context.init ~consensus_threshold:1 5 >>=? fun (genesis, _) ->
+  Context.init_n ~consensus_threshold:1 5 () >>=? fun (genesis, _) ->
   Block.bake genesis >>=? fun b1 ->
   let module V = Plugin.RPC.Validators in
   (Context.get_endorsers (B b1) >>=? function
@@ -409,7 +409,7 @@ let test_endorsement_for_next_round () =
 
 (** Endorsement of grandparent  *)
 let test_endorsement_grandparent () =
-  Context.init ~consensus_threshold:0 1 >>=? fun (genesis, _) ->
+  Context.init1 ~consensus_threshold:0 () >>=? fun (genesis, _contract) ->
   Block.bake genesis >>=? fun b_gp ->
   Block.bake b_gp >>=? fun b ->
   Incremental.begin_construction ~mempool_mode:true b >>=? fun i ->
@@ -425,7 +425,7 @@ let test_endorsement_grandparent () =
 
 (** Double inclusion of grandparent endorsement *)
 let test_double_endorsement_grandparent () =
-  Context.init ~consensus_threshold:0 1 >>=? fun (genesis, _) ->
+  Context.init1 ~consensus_threshold:0 () >>=? fun (genesis, _contract) ->
   Block.bake genesis >>=? fun b_gp ->
   Block.bake b_gp >>=? fun b ->
   Incremental.begin_construction ~mempool_mode:true b >>=? fun i ->
@@ -448,7 +448,7 @@ let test_double_endorsement_grandparent () =
 
 (** Endorsement of grandparent on same slot as parent *)
 let test_endorsement_grandparent_same_slot () =
-  Context.init ~consensus_threshold:0 1 >>=? fun (genesis, _) ->
+  Context.init1 ~consensus_threshold:0 () >>=? fun (genesis, _contract) ->
   Block.bake genesis >>=? fun b_gp ->
   Block.bake b_gp >>=? fun b ->
   Incremental.begin_construction ~mempool_mode:true b >>=? fun i ->
@@ -466,7 +466,7 @@ let test_endorsement_grandparent_same_slot () =
 
 (** Endorsement of grandparent in application mode should be rejected *)
 let test_endorsement_grandparent_application () =
-  Context.init ~consensus_threshold:0 1 >>=? fun (genesis, _) ->
+  Context.init1 ~consensus_threshold:0 () >>=? fun (genesis, _contract) ->
   Block.bake genesis >>=? fun b_gp ->
   Block.bake b_gp >>=? fun b ->
   Op.endorsement ~endorsed_block:b_gp (B genesis) () >>=? fun op ->
@@ -478,7 +478,7 @@ let test_endorsement_grandparent_application () =
 
 (** Endorsement of grandparent in full construction mode should be rejected *)
 let test_endorsement_grandparent_full_construction () =
-  Context.init ~consensus_threshold:0 1 >>=? fun (genesis, _) ->
+  Context.init1 ~consensus_threshold:0 () >>=? fun (genesis, _contract) ->
   Block.bake genesis >>=? fun b_gp ->
   Block.bake b_gp >>=? fun b ->
   Incremental.begin_construction b >>=? fun i ->
diff --git a/src/proto_alpha/lib_protocol/test/integration/consensus/test_helpers_rpcs.ml b/src/proto_alpha/lib_protocol/test/integration/consensus/test_helpers_rpcs.ml
index b70757335d55..78df0e7cc262 100644
--- a/src/proto_alpha/lib_protocol/test/integration/consensus/test_helpers_rpcs.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/consensus/test_helpers_rpcs.ml
@@ -39,7 +39,7 @@ open Alpha_context
    Future levels or cycles are not tested because it's hard in this framework,
    using only RPCs, to fabricate them. *)
 let test_baking_rights () =
-  Context.init 2 >>=? fun (b, contracts) ->
+  Context.init2 () >>=? fun (b, (c1, _c2)) ->
   let open Plugin.RPC.Baking_rights in
   (* default max_round returns 65 results *)
   get Block.rpc_ctxt b ~all:true >>=? fun rights ->
@@ -49,10 +49,7 @@ let test_baking_rights () =
   get Block.rpc_ctxt b ~all:true ~max_round >>=? fun rights ->
   assert (Compare.List_length_with.(rights = max_round + 1)) ;
   (* filtering by delegate *)
-  let d =
-    Option.bind (List.nth contracts 0) Contract.is_implicit
-    |> WithExceptions.Option.get ~loc:__LOC__
-  in
+  let d = Contract.is_implicit c1 |> WithExceptions.Option.get ~loc:__LOC__ in
   get Block.rpc_ctxt b ~all:true ~delegates:[d] >>=? fun rights ->
   assert (List.for_all (fun {delegate; _} -> delegate = d) rights) ;
   (* filtering by cycle *)
diff --git a/src/proto_alpha/lib_protocol/test/integration/consensus/test_participation.ml b/src/proto_alpha/lib_protocol/test/integration/consensus/test_participation.ml
index 64c36f2b1f67..0067b1b1902f 100644
--- a/src/proto_alpha/lib_protocol/test/integration/consensus/test_participation.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/consensus/test_participation.ml
@@ -67,7 +67,7 @@ let bake_and_endorse_once (b_pred, b_cur) baker endorser =
 *)
 let test_participation ~sufficient_participation () =
   let n_accounts = 2 in
-  Context.init ~consensus_threshold:1 n_accounts >>=? fun (b0, accounts) ->
+  Context.init_n ~consensus_threshold:1 n_accounts () >>=? fun (b0, accounts) ->
   Context.get_constants (B b0) >>=? fun csts ->
   let blocks_per_cycle = Int32.to_int csts.parametric.blocks_per_cycle in
   let mpr = csts.parametric.minimal_participation_ratio in
@@ -125,10 +125,7 @@ let test_participation ~sufficient_participation () =
    non-participating account. *)
 let test_participation_rpc () =
   let n_accounts = 2 in
-  Context.init ~consensus_threshold:1 n_accounts >>=? fun (b0, accounts) ->
-  let (account1, account2) =
-    match accounts with a1 :: a2 :: _ -> (a1, a2) | _ -> assert false
-  in
+  Context.init2 ~consensus_threshold:1 () >>=? fun (b0, (account1, account2)) ->
   Context.Contract.pkh account1 >>=? fun del1 ->
   Context.Contract.pkh account2 >>=? fun del2 ->
   Context.get_constants (B b0) >>=? fun csts ->
diff --git a/src/proto_alpha/lib_protocol/test/integration/consensus/test_preendorsement.ml b/src/proto_alpha/lib_protocol/test/integration/consensus/test_preendorsement.ml
index 4c192060e655..5cb18b2483ff 100644
--- a/src/proto_alpha/lib_protocol/test/integration/consensus/test_preendorsement.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/consensus/test_preendorsement.ml
@@ -39,7 +39,7 @@ open Alpha_context
 (****************************************************************)
 
 let init_genesis ?policy () =
-  Context.init ~consensus_threshold:0 5 >>=? fun (genesis, _) ->
+  Context.init_n ~consensus_threshold:0 5 () >>=? fun (genesis, _contracts) ->
   Block.bake ?policy genesis >>=? fun b -> return (genesis, b)
 
 (****************************************************************)
diff --git a/src/proto_alpha/lib_protocol/test/integration/consensus/test_preendorsement_functor.ml b/src/proto_alpha/lib_protocol/test/integration/consensus/test_preendorsement_functor.ml
index 0478885ecae9..a1f93f13e021 100644
--- a/src/proto_alpha/lib_protocol/test/integration/consensus/test_preendorsement_functor.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/consensus/test_preendorsement_functor.ml
@@ -57,7 +57,7 @@ end = struct
       ?(get_delegate_and_slot =
         fun _predpred _pred _curr -> return (None, None))
       ?(post_process = Ok (fun _ -> return_unit)) ~loc () =
-    Context.init ~consensus_threshold:1 5 >>=? fun (genesis, _) ->
+    Context.init_n ~consensus_threshold:1 5 () >>=? fun (genesis, _contracts) ->
     bake genesis >>=? fun b1 ->
     Op.endorsement ~endorsed_block:b1 (B genesis) () >>=? fun endo ->
     let endo = Operation.pack endo in
diff --git a/src/proto_alpha/lib_protocol/test/integration/consensus/test_seed.ml b/src/proto_alpha/lib_protocol/test/integration/consensus/test_seed.ml
index 90ce2028dd0a..6fcafa49efd3 100644
--- a/src/proto_alpha/lib_protocol/test/integration/consensus/test_seed.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/consensus/test_seed.ml
@@ -39,7 +39,7 @@ open Protocol
 (** Baking [blocks_per_commitment] blocks without a [seed_nonce_hash]
     commitment fails with an "Invalid commitment in block header" error. *)
 let test_no_commitment () =
-  Context.init ~consensus_threshold:0 5 >>=? fun (b, _) ->
+  Context.init_n ~consensus_threshold:0 5 () >>=? fun (b, _contracts) ->
   Context.get_constants (B b)
   >>=? fun {parametric = {blocks_per_commitment; _}; _} ->
   let blocks_per_commitment = Int32.to_int blocks_per_commitment in
@@ -63,7 +63,7 @@ let test_no_commitment () =
     - revealing twice produces an error *)
 let test_revelation_early_wrong_right_twice () =
   let open Assert in
-  Context.init ~consensus_threshold:0 5 >>=? fun (b, _) ->
+  Context.init_n ~consensus_threshold:0 5 () >>=? fun (b, _contracts) ->
   Context.get_constants (B b) >>=? fun csts ->
   let tip = csts.parametric.seed_nonce_revelation_tip in
   let blocks_per_commitment =
@@ -145,7 +145,7 @@ let test_revelation_early_wrong_right_twice () =
 let test_revelation_missing_and_late () =
   let open Context in
   let open Assert in
-  Context.init ~consensus_threshold:0 5 >>=? fun (b, _) ->
+  Context.init_n ~consensus_threshold:0 5 () >>=? fun (b, _contracts) ->
   get_constants (B b) >>=? fun csts ->
   let blocks_per_commitment =
     Int32.to_int csts.parametric.blocks_per_commitment
diff --git a/src/proto_alpha/lib_protocol/test/integration/gas/test_gas_levels.ml b/src/proto_alpha/lib_protocol/test/integration/gas/test_gas_levels.ml
index e61e2e6db1b1..54fe48a4537b 100644
--- a/src/proto_alpha/lib_protocol/test/integration/gas/test_gas_levels.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/gas/test_gas_levels.ml
@@ -49,7 +49,7 @@ let succeed x = match x with Ok _ -> true | _ -> false
 let failed x = not (succeed x)
 
 let dummy_context () =
-  Context.init ~consensus_threshold:0 1 >>=? fun (block, _) ->
+  Context.init1 ~consensus_threshold:0 () >>=? fun (block, _contract) ->
   Raw_context.prepare
     ~level:Int32.zero
     ~predecessor_timestamp:Time.Protocol.epoch
@@ -255,8 +255,7 @@ let originate_contract block source script =
   Block.bake ~operation block >>=? fun block -> return (block, dst)
 
 let init_block to_originate =
-  Context.init ~consensus_threshold:0 1 >>=? fun (block, contracts) ->
-  let src = WithExceptions.Option.get ~loc:__LOC__ @@ List.hd contracts in
+  Context.init1 ~consensus_threshold:0 () >>=? fun (block, src) ->
   (*** originate contracts ***)
   let rec full_originate block originated = function
     | [] -> return (block, List.rev originated)
diff --git a/src/proto_alpha/lib_protocol/test/integration/michelson/test_annotations.ml b/src/proto_alpha/lib_protocol/test/integration/michelson/test_annotations.ml
index 83eda41acd50..a6defcc353e2 100644
--- a/src/proto_alpha/lib_protocol/test/integration/michelson/test_annotations.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/michelson/test_annotations.ml
@@ -61,9 +61,8 @@ let contract_factory_with_annotations =
 let lazy_none = Script.lazy_expr (Expr.from_string "None")
 
 let init_and_originate contract_code_string =
-  Context.init ~consensus_threshold:0 1 >>=? fun (b, contracts) ->
+  Context.init1 ~consensus_threshold:0 () >>=? fun (b, source) ->
   Incremental.begin_construction b >>=? fun inc ->
-  let source = WithExceptions.Option.get ~loc:__LOC__ @@ List.hd contracts in
   let code = Expr.toplevel_from_string contract_code_string in
   let script = Script.{code = lazy_expr code; storage = lazy_none} in
   Op.contract_origination (I inc) source ~script >>=? fun (operation, addr) ->
diff --git a/src/proto_alpha/lib_protocol/test/integration/michelson/test_global_constants_storage.ml b/src/proto_alpha/lib_protocol/test/integration/michelson/test_global_constants_storage.ml
index 3d384948ab29..1ad510b6c707 100644
--- a/src/proto_alpha/lib_protocol/test/integration/michelson/test_global_constants_storage.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/michelson/test_global_constants_storage.ml
@@ -40,11 +40,6 @@ let get_next_context b =
   Incremental.begin_construction b >>=? fun b ->
   return (Incremental.alpha_ctxt b)
 
-let register_two_contracts ?consensus_threshold () =
-  Context.init ?consensus_threshold 2 >|=? function
-  | (_, []) | (_, [_]) -> assert false
-  | (b, contract_1 :: contract_2 :: _) -> (b, contract_1, contract_2)
-
 let assert_proto_error_id loc id result =
   let test err =
     (Error_monad.find_info_of_error err).id
diff --git a/src/proto_alpha/lib_protocol/test/integration/michelson/test_interpretation.ml b/src/proto_alpha/lib_protocol/test/integration/michelson/test_interpretation.ml
index 631f4901db68..8525753db6fe 100644
--- a/src/proto_alpha/lib_protocol/test/integration/michelson/test_interpretation.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/michelson/test_interpretation.ml
@@ -39,7 +39,7 @@ open Script_interpreter
 open Error_monad_operators
 
 let test_context () =
-  Context.init 3 >>=? fun (b, _cs) ->
+  Context.init3 () >>=? fun (b, _cs) ->
   Incremental.begin_construction b >>=? fun v ->
   return (Incremental.alpha_ctxt v)
 
diff --git a/src/proto_alpha/lib_protocol/test/integration/michelson/test_patched_contracts.ml b/src/proto_alpha/lib_protocol/test/integration/michelson/test_patched_contracts.ml
index b952cb4e9b47..ebfb0880b777 100644
--- a/src/proto_alpha/lib_protocol/test/integration/michelson/test_patched_contracts.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/michelson/test_patched_contracts.ml
@@ -162,7 +162,7 @@ module Legacy_patch_test (Patches : LEGACY_SCRIPT_PATCHES) :
     (* Number 3 below controls how many accounts should be
        created. This number shouldn't be too small or the context
        won't have enough tokens to form a roll. *)
-    let* (block, _) = Context.init 3 in
+    let* (block, _contracts) = Context.init3 () in
     let* inc = Incremental.begin_construction block in
     let ctxt = Incremental.alpha_ctxt inc in
     let* _ =
diff --git a/src/proto_alpha/lib_protocol/test/integration/michelson/test_sapling.ml b/src/proto_alpha/lib_protocol/test/integration/michelson/test_sapling.ml
index 53da0dca16e0..704381c37c1a 100644
--- a/src/proto_alpha/lib_protocol/test/integration/michelson/test_sapling.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/michelson/test_sapling.ml
@@ -47,7 +47,7 @@ module Raw_context_tests = struct
      constant value `uncommitted` for which we know the corresponding root and
      tests that the returned root is as expected. *)
   let commitments_add_uncommitted () =
-    Context.init 1 >>=? fun (b, _) ->
+    Context.init1 () >>=? fun (b, _contract) ->
     Raw_context.prepare
       b.context
       ~level:b.header.shell.level
@@ -86,7 +86,7 @@ module Raw_context_tests = struct
      however committing to disk twice the same nf causes a storage error by
      trying to initialize the same key twice. *)
   let nullifier_double () =
-    Context.init 1 >>=? fun (b, _) ->
+    Context.init1 () >>=? fun (b, _contract) ->
     Raw_context.prepare
       b.context
       ~level:b.header.shell.level
@@ -115,7 +115,7 @@ module Raw_context_tests = struct
      memory). We then check that nullifier_mem answers true for those two lists
      and false for a third one. *)
   let nullifier_test () =
-    Context.init 1 >>=? fun (b, _) ->
+    Context.init1 () >>=? fun (b, _contract) ->
     Raw_context.prepare
       b.context
       ~level:b.header.shell.level
@@ -170,7 +170,7 @@ module Raw_context_tests = struct
   let cm_cipher_test () =
     Random.self_init () ;
     let memo_size = Random.int 200 in
-    Context.init 1 >>=? fun (b, _) ->
+    Context.init1 () >>=? fun (b, _contract) ->
     Raw_context.prepare
       b.context
       ~level:b.header.shell.level
@@ -212,7 +212,7 @@ module Raw_context_tests = struct
   let list_insertion_test () =
     Random.self_init () ;
     let memo_size = Random.int 200 in
-    Context.init 1 >>=? fun (b, _) ->
+    Context.init1 () >>=? fun (b, _contract) ->
     Raw_context.prepare
       b.context
       ~level:b.header.shell.level
@@ -287,7 +287,7 @@ module Raw_context_tests = struct
         (Int32.to_int Sapling_storage.Roots.size + 10)
         (fun _ -> gen_root ())
     in
-    Context.init 1 >>=? fun (b, _) ->
+    Context.init1 () >>=? fun (b, _contract) ->
     Raw_context.prepare
       b.context
       ~level:b.header.shell.level
@@ -347,7 +347,7 @@ module Raw_context_tests = struct
     >>=? fun _ -> return_unit
 
   let test_get_memo_size () =
-    Context.init 1 >>=? fun (b, _) ->
+    Context.init1 () >>=? fun (b, _contract) ->
     Raw_context.prepare
       b.context
       ~level:b.header.shell.level
diff --git a/src/proto_alpha/lib_protocol/test/integration/michelson/test_ticket_accounting.ml b/src/proto_alpha/lib_protocol/test/integration/michelson/test_ticket_accounting.ml
index 16e5ec3b5938..5abb58844153 100644
--- a/src/proto_alpha/lib_protocol/test/integration/michelson/test_ticket_accounting.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/michelson/test_ticket_accounting.ml
@@ -159,8 +159,7 @@ let make_alloc big_map_id alloc updates =
 
 let init () =
   let open Lwt_result_syntax in
-  let* (block, contracts) = Context.init 1 in
-  let source = WithExceptions.Option.get ~loc:__LOC__ @@ List.hd contracts in
+  let* (block, source) = Context.init1 () in
   let* (operation, originated) =
     Op.contract_origination (B block) source ~script:Op.dummy_script
   in
@@ -170,10 +169,7 @@ let init () =
 
 (** Initializes one address for operations and one baker. *)
 let init_for_operation () =
-  Context.init ~consensus_threshold:0 2 >|=? fun (block, contracts) ->
-  let (src0, src1) =
-    match contracts with src0 :: src1 :: _ -> (src0, src1) | _ -> assert false
-  in
+  Context.init2 ~consensus_threshold:0 () >|=? fun (block, (src0, src1)) ->
   let baker =
     match Alpha_context.Contract.is_implicit src0 with
     | Some v -> v
diff --git a/src/proto_alpha/lib_protocol/test/integration/michelson/test_ticket_balance_key.ml b/src/proto_alpha/lib_protocol/test/integration/michelson/test_ticket_balance_key.ml
index d0a972d392e4..49fbaf045aa0 100644
--- a/src/proto_alpha/lib_protocol/test/integration/michelson/test_ticket_balance_key.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/michelson/test_ticket_balance_key.ml
@@ -40,7 +40,7 @@ let ( let* ) m f = m >>=? f
 let wrap m = m >|= Environment.wrap_tzresult
 
 let new_ctxt () =
-  let* (block, _) = Context.init 1 in
+  let* (block, _contract) = Context.init1 () in
   let* incr = Incremental.begin_construction block in
   return @@ Incremental.alpha_ctxt incr
 
diff --git a/src/proto_alpha/lib_protocol/test/integration/michelson/test_ticket_lazy_storage_diff.ml b/src/proto_alpha/lib_protocol/test/integration/michelson/test_ticket_lazy_storage_diff.ml
index c9818c6eb9b2..6cce95cf1cd2 100644
--- a/src/proto_alpha/lib_protocol/test/integration/michelson/test_ticket_lazy_storage_diff.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/michelson/test_ticket_lazy_storage_diff.ml
@@ -133,8 +133,7 @@ let make_alloc big_map_id alloc updates =
     (Update {init = Lazy_storage.Alloc alloc; updates})
 
 let init () =
-  let* (block, contracts) = Context.init 1 in
-  let source = WithExceptions.Option.get ~loc:__LOC__ @@ List.hd contracts in
+  let* (block, source) = Context.init1 () in
   let* (operation, originated) =
     Op.contract_origination (B block) source ~script:Op.dummy_script
   in
diff --git a/src/proto_alpha/lib_protocol/test/integration/michelson/test_ticket_operations_diff.ml b/src/proto_alpha/lib_protocol/test/integration/michelson/test_ticket_operations_diff.ml
index 924b502223d8..986c0c83fc2a 100644
--- a/src/proto_alpha/lib_protocol/test/integration/michelson/test_ticket_operations_diff.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/michelson/test_ticket_operations_diff.ml
@@ -180,11 +180,8 @@ let string_token ~ticketer content =
 
 (** Initializes one address for operations and one baker. *)
 let init ?tx_rollup_enable () =
-  Context.init ?tx_rollup_enable ~consensus_threshold:0 2
-  >|=? fun (block, contracts) ->
-  let (src0, src1) =
-    match contracts with src0 :: src1 :: _ -> (src0, src1) | _ -> assert false
-  in
+  Context.init2 ?tx_rollup_enable ~consensus_threshold:0 ()
+  >|=? fun (block, (src0, src1)) ->
   let baker =
     match Alpha_context.Contract.is_implicit src0 with
     | Some v -> v
diff --git a/src/proto_alpha/lib_protocol/test/integration/michelson/test_ticket_scanner.ml b/src/proto_alpha/lib_protocol/test/integration/michelson/test_ticket_scanner.ml
index a1601223180d..b7203e61048c 100644
--- a/src/proto_alpha/lib_protocol/test/integration/michelson/test_ticket_scanner.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/michelson/test_ticket_scanner.ml
@@ -41,7 +41,7 @@ let ( let* ) m f = m >>=? f
 let wrap m = m >|= Environment.wrap_tzresult
 
 let new_ctxt () =
-  let* (block, _) = Context.init 1 in
+  let* (block, _contract) = Context.init1 () in
   let* incr = Incremental.begin_construction block in
   return @@ Incremental.alpha_ctxt incr
 
@@ -166,8 +166,7 @@ let make_string_tickets ctxt ticketer_amounts =
     ([], ctxt)
 
 let tickets_from_big_map_ref ~pre_populated value_exp =
-  let* (block, contracts) = Context.init 1 in
-  let source = WithExceptions.Option.get ~loc:__LOC__ @@ List.hd contracts in
+  let* (block, source) = Context.init1 () in
   let* (operation, originated) =
     Op.contract_origination (B block) source ~script:Op.dummy_script
   in
diff --git a/src/proto_alpha/lib_protocol/test/integration/michelson/test_ticket_storage.ml b/src/proto_alpha/lib_protocol/test/integration/michelson/test_ticket_storage.ml
index 6056bd184956..006ce63f75f6 100644
--- a/src/proto_alpha/lib_protocol/test/integration/michelson/test_ticket_storage.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/michelson/test_ticket_storage.ml
@@ -40,7 +40,7 @@ let ( let* ) m f = m >>=? f
 let wrap m = m >|= Environment.wrap_tzresult
 
 let make_context () =
-  let* (block, _) = Context.init 1 in
+  let* (block, _contract) = Context.init1 () in
   let* incr = Incremental.begin_construction block in
   return (Incremental.alpha_ctxt incr)
 
diff --git a/src/proto_alpha/lib_protocol/test/integration/michelson/test_timelock.ml b/src/proto_alpha/lib_protocol/test/integration/michelson/test_timelock.ml
index 3ef50a35a565..4bba8a7ac094 100644
--- a/src/proto_alpha/lib_protocol/test/integration/michelson/test_timelock.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/michelson/test_timelock.ml
@@ -75,8 +75,7 @@ let contract_test () =
     Incremental.add_operation incr operation >>=? fun incr ->
     Incremental.finalize_block incr >|=? fun b -> (dst, b)
   in
-  Context.init ~consensus_threshold:0 3 >>=? fun (b, contracts) ->
-  let src = match contracts with hd :: _ -> hd | _ -> assert false in
+  Context.init3 ~consensus_threshold:0 () >>=? fun (b, (src, _c2, _c3)) ->
   originate_contract "contracts/timelock.tz" "0xaa" src b >>=? fun (dst, b) ->
   let (public, secret) = Timelock.gen_rsa_keys () in
   let locked_value = Timelock.gen_locked_value public in
diff --git a/src/proto_alpha/lib_protocol/test/integration/michelson/test_typechecking.ml b/src/proto_alpha/lib_protocol/test/integration/michelson/test_typechecking.ml
index 978e10fe7f48..9919530c8444 100644
--- a/src/proto_alpha/lib_protocol/test/integration/michelson/test_typechecking.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/michelson/test_typechecking.ml
@@ -51,7 +51,7 @@ let test_unparse_view () =
   let script =
     Script.{code = lazy_expr contract_expr; storage = lazy_expr storage_expr}
   in
-  Context.init 3 >>=? fun (b, _cs) ->
+  Context.init3 () >>=? fun (b, _cs) ->
   Incremental.begin_construction b >>=? fun v ->
   let ctx = Incremental.alpha_ctxt v in
   Script_ir_translator.parse_and_unparse_script_unaccounted
@@ -66,13 +66,12 @@ let test_unparse_view () =
   Alcotest.(check bytes) "didn't match" bef aft |> return
 
 let test_context () =
-  Context.init ~consensus_threshold:0 3 >>=? fun (b, _cs) ->
+  Context.init3 ~consensus_threshold:0 () >>=? fun (b, _cs) ->
   Incremental.begin_construction b >>=? fun v ->
   return (Incremental.alpha_ctxt v)
 
 let test_context_with_nat_nat_big_map () =
-  Context.init 3 >>=? fun (b, contracts) ->
-  let source = WithExceptions.Option.get ~loc:__LOC__ @@ List.hd contracts in
+  Context.init3 () >>=? fun (b, (source, _c2, _c3)) ->
   Op.contract_origination (B b) source ~script:Op.dummy_script
   >>=? fun (operation, originated) ->
   Block.bake ~operation b >>=? fun b ->
diff --git a/src/proto_alpha/lib_protocol/test/integration/operations/test_activation.ml b/src/proto_alpha/lib_protocol/test/integration/operations/test_activation.ml
index 0304dc2ddd63..318e08c656a5 100644
--- a/src/proto_alpha/lib_protocol/test/integration/operations/test_activation.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/operations/test_activation.ml
@@ -336,18 +336,18 @@ let secrets () =
 (** Helper: Create a genesis block with predefined commitments,
     accounts and balances. *)
 let activation_init () =
-  Context.init ~consensus_threshold:0 ~commitments 1 >|=? fun (b, cs) ->
-  secrets () |> fun ss -> (b, cs, ss)
+  Context.init1 ~consensus_threshold:0 ~commitments () >|=? fun (b, c) ->
+  secrets () |> fun ss -> (b, c, ss)
 
 (** Verify the genesis block created by [activation_init] can be
     baked. *)
 let test_simple_init_with_commitments () =
-  activation_init () >>=? fun (blk, _contracts, _secrets) ->
+  activation_init () >>=? fun (blk, _contract, _secrets) ->
   Block.bake blk >>=? fun _ -> return_unit
 
 (** A single activation *)
 let test_single_activation () =
-  activation_init () >>=? fun (blk, _contracts, secrets) ->
+  activation_init () >>=? fun (blk, _contract, secrets) ->
   let ({account; activation_code; amount = expected_amount; _} as _first_one) =
     WithExceptions.Option.get ~loc:__LOC__ @@ List.hd secrets
   in
@@ -369,7 +369,7 @@ let test_single_activation () =
 
 (** 10 activations, one per bake. *)
 let test_multi_activation_1 () =
-  activation_init () >>=? fun (blk, _contracts, secrets) ->
+  activation_init () >>=? fun (blk, _contract, secrets) ->
   List.fold_left_es
     (fun blk {account; activation_code; amount = expected_amount; _} ->
       Op.activation (B blk) account activation_code >>=? fun operation ->
@@ -386,7 +386,7 @@ let test_multi_activation_1 () =
 
 (** All of the 10 activations occur in one bake. *)
 let test_multi_activation_2 () =
-  activation_init () >>=? fun (blk, _contracts, secrets) ->
+  activation_init () >>=? fun (blk, _contract, secrets) ->
   List.fold_left_es
     (fun ops {account; activation_code; _} ->
       Op.activation (B blk) account activation_code >|=? fun op -> op :: ops)
@@ -406,13 +406,10 @@ let test_multi_activation_2 () =
 
 (** Transfer with activated account. *)
 let test_activation_and_transfer () =
-  activation_init () >>=? fun (blk, contracts, secrets) ->
+  activation_init () >>=? fun (blk, bootstrap_contract, secrets) ->
   let ({account; activation_code; _} as _first_one) =
     WithExceptions.Option.get ~loc:__LOC__ @@ List.hd secrets
   in
-  let bootstrap_contract =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.hd contracts
-  in
   let first_contract = Contract.implicit_contract account in
   Op.activation (B blk) account activation_code >>=? fun operation ->
   Block.bake ~operation blk >>=? fun blk ->
@@ -432,13 +429,10 @@ let test_activation_and_transfer () =
 
 (** Transfer to an unactivated account and then activating it. *)
 let test_transfer_to_unactivated_then_activate () =
-  activation_init () >>=? fun (blk, contracts, secrets) ->
+  activation_init () >>=? fun (blk, bootstrap_contract, secrets) ->
   let ({account; activation_code; amount} as _first_one) =
     WithExceptions.Option.get ~loc:__LOC__ @@ List.hd secrets
   in
-  let bootstrap_contract =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.hd contracts
-  in
   let unactivated_commitment_contract = Contract.implicit_contract account in
   Context.Contract.balance (B blk) bootstrap_contract >>=? fun b_amount ->
   b_amount /? 2L >>?= fun b_half_amount ->
@@ -467,7 +461,7 @@ let test_transfer_to_unactivated_then_activate () =
 (** Invalid pkh activation: expected to fail as the context does not
     contain any commitment. *)
 let test_invalid_activation_with_no_commitments () =
-  Context.init 1 >>=? fun (blk, _) ->
+  Context.init1 () >>=? fun (blk, _contract) ->
   let secrets = secrets () in
   let ({account; activation_code; _} as _first_one) =
     WithExceptions.Option.get ~loc:__LOC__ @@ List.hd secrets
@@ -478,7 +472,7 @@ let test_invalid_activation_with_no_commitments () =
 
 (** Wrong activation: wrong secret given in the operation. *)
 let test_invalid_activation_wrong_secret () =
-  activation_init () >>=? fun (blk, _, secrets) ->
+  activation_init () >>=? fun (blk, _contract, secrets) ->
   let ({account; _} as _first_one) =
     WithExceptions.Option.get ~loc:__LOC__ @@ List.nth secrets 0
   in
@@ -492,7 +486,7 @@ let test_invalid_activation_wrong_secret () =
 (** Invalid pkh activation : expected to fail as the context does not
     contain an associated commitment. *)
 let test_invalid_activation_inexistent_pkh () =
-  activation_init () >>=? fun (blk, _, secrets) ->
+  activation_init () >>=? fun (blk, _contract, secrets) ->
   let ({activation_code; _} as _first_one) =
     WithExceptions.Option.get ~loc:__LOC__ @@ List.hd secrets
   in
@@ -507,7 +501,7 @@ let test_invalid_activation_inexistent_pkh () =
 (** Invalid pkh activation : expected to fail as the commitment has
     already been claimed. *)
 let test_invalid_double_activation () =
-  activation_init () >>=? fun (blk, _, secrets) ->
+  activation_init () >>=? fun (blk, _contract, secrets) ->
   let ({account; activation_code; _} as _first_one) =
     WithExceptions.Option.get ~loc:__LOC__ @@ List.hd secrets
   in
@@ -520,13 +514,10 @@ let test_invalid_double_activation () =
 
 (** Transfer from an unactivated commitment account. *)
 let test_invalid_transfer_from_unactivated_account () =
-  activation_init () >>=? fun (blk, contracts, secrets) ->
+  activation_init () >>=? fun (blk, bootstrap_contract, secrets) ->
   let ({account; _} as _first_one) =
     WithExceptions.Option.get ~loc:__LOC__ @@ List.hd secrets
   in
-  let bootstrap_contract =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.hd contracts
-  in
   let unactivated_commitment_contract = Contract.implicit_contract account in
   (* No activation *)
   Op.transaction
diff --git a/src/proto_alpha/lib_protocol/test/integration/operations/test_combined_operations.ml b/src/proto_alpha/lib_protocol/test/integration/operations/test_combined_operations.ml
index 43fc555cde62..faff59040f8f 100644
--- a/src/proto_alpha/lib_protocol/test/integration/operations/test_combined_operations.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/operations/test_combined_operations.ml
@@ -52,10 +52,7 @@ let gas_limit = Alpha_context.Gas.Arith.integral_of_int_exn 3000
 
 (** Groups ten transactions between the same parties. *)
 let test_multiple_transfers () =
-  Context.init 3 >>=? fun (blk, contracts) ->
-  let (c1, c2, c3) =
-    match contracts with [c1; c2; c3] -> (c1, c2, c3) | _ -> assert false
-  in
+  Context.init3 () >>=? fun (blk, (c1, c2, c3)) ->
   List.map_es
     (fun _ -> Op.transaction ~gas_limit (B blk) c1 c2 Tez.one)
     (1 -- 10)
@@ -84,10 +81,7 @@ let test_multiple_transfers () =
 
 (** Groups ten delegated originations. *)
 let test_multiple_origination_and_delegation () =
-  Context.init 2 >>=? fun (blk, contracts) ->
-  let (c1, c2) =
-    match contracts with [c1; c2] -> (c1, c2) | _ -> assert false
-  in
+  Context.init2 () >>=? fun (blk, (c1, c2)) ->
   let n = 10 in
   Context.get_constants (B blk)
   >>=? fun {parametric = {origination_size; cost_per_byte; _}; _} ->
@@ -172,10 +166,7 @@ let expect_failure = function
     Checks that the receipt is consistent.
     Variant without fees. *)
 let test_failing_operation_in_the_middle () =
-  Context.init 2 >>=? fun (blk, contracts) ->
-  let (c1, c2) =
-    match contracts with [c1; c2] -> (c1, c2) | _ -> assert false
-  in
+  Context.init2 () >>=? fun (blk, (c1, c2)) ->
   Op.transaction ~gas_limit ~fee:Tez.zero (B blk) c1 c2 Tez.one >>=? fun op1 ->
   Op.transaction ~gas_limit ~fee:Tez.zero (B blk) c1 c2 Test_tez.max_tez
   >>=? fun op2 ->
@@ -221,10 +212,7 @@ let test_failing_operation_in_the_middle () =
     Checks that the receipt is consistent.
     Variant with fees, that should be spent even in case of failure. *)
 let test_failing_operation_in_the_middle_with_fees () =
-  Context.init 2 >>=? fun (blk, contracts) ->
-  let (c1, c2) =
-    match contracts with [c1; c2] -> (c1, c2) | _ -> assert false
-  in
+  Context.init2 () >>=? fun (blk, (c1, c2)) ->
   Op.transaction ~fee:Tez.one (B blk) c1 c2 Tez.one >>=? fun op1 ->
   Op.transaction ~fee:Tez.one (B blk) c1 c2 Test_tez.max_tez >>=? fun op2 ->
   Op.transaction ~fee:Tez.one (B blk) c1 c2 Tez.one >>=? fun op3 ->
@@ -273,55 +261,45 @@ let test_failing_operation_in_the_middle_with_fees () =
   return_unit
 
 let test_wrong_signature_in_the_middle () =
-  Context.init 2 >>=? function
-  | (_, []) | (_, [_]) -> assert false
-  | (blk, c1 :: c2 :: _) ->
-      Op.transaction ~gas_limit ~fee:Tez.one (B blk) c1 c2 Tez.one
-      >>=? fun op1 ->
-      Op.transaction ~gas_limit ~fee:Tez.one (B blk) c2 c1 Tez.one
-      >>=? fun op2 ->
-      Incremental.begin_construction blk >>=? fun inc ->
-      (* Make legit transfers, performing reveals *)
-      Incremental.add_operation inc op1 >>=? fun inc ->
-      Incremental.add_operation inc op2 >>=? fun inc ->
-      (* Make c2 reach counter 5 *)
-      Op.transaction ~gas_limit ~fee:Tez.one (I inc) c2 c1 Tez.one
-      >>=? fun op ->
-      Incremental.add_operation inc op >>=? fun inc ->
-      Op.transaction ~gas_limit ~fee:Tez.one (I inc) c2 c1 Tez.one
-      >>=? fun op ->
-      Incremental.add_operation inc op >>=? fun inc ->
-      Op.transaction ~gas_limit ~fee:Tez.one (I inc) c2 c1 Tez.one
-      >>=? fun op ->
-      Incremental.add_operation inc op >>=? fun inc ->
-      (* Cook transactions for actual test *)
-      Op.transaction ~gas_limit ~fee:Tez.one (I inc) c1 c2 Tez.one
-      >>=? fun op1 ->
-      Op.transaction ~gas_limit ~fee:Tez.one (I inc) c1 c2 Tez.one
-      >>=? fun op2 ->
-      Op.transaction ~gas_limit ~fee:Tez.one (I inc) c1 c2 Tez.one
-      >>=? fun op3 ->
-      Op.transaction ~gas_limit ~fee:Tez.one (I inc) c2 c1 Tez.one
-      >>=? fun spurious_operation ->
-      let operations = [op1; op2; op3] in
-      Op.combine_operations ~spurious_operation ~source:c1 (I inc) operations
-      >>=? fun operation ->
-      let expect_apply_failure = function
-        | Environment.Ecoproto_error err :: _ ->
-            Assert.test_error_encodings err ;
-            let error_info =
-              Error_monad.find_info_of_error (Environment.wrap_tzerror err)
-            in
-            if error_info.title = "Inconsistent sources in operation pack" then
-              return_unit
-            else failwith "unexpected error"
-        | _ ->
-            failwith
-              "Packed operation has invalid source in the middle : operation \
-               expected to fail."
-      in
-      Incremental.add_operation ~expect_apply_failure inc operation
-      >>=? fun _inc -> return_unit
+  Context.init2 () >>=? fun (blk, (c1, c2)) ->
+  Op.transaction ~gas_limit ~fee:Tez.one (B blk) c1 c2 Tez.one >>=? fun op1 ->
+  Op.transaction ~gas_limit ~fee:Tez.one (B blk) c2 c1 Tez.one >>=? fun op2 ->
+  Incremental.begin_construction blk >>=? fun inc ->
+  (* Make legit transfers, performing reveals *)
+  Incremental.add_operation inc op1 >>=? fun inc ->
+  Incremental.add_operation inc op2 >>=? fun inc ->
+  (* Make c2 reach counter 5 *)
+  Op.transaction ~gas_limit ~fee:Tez.one (I inc) c2 c1 Tez.one >>=? fun op ->
+  Incremental.add_operation inc op >>=? fun inc ->
+  Op.transaction ~gas_limit ~fee:Tez.one (I inc) c2 c1 Tez.one >>=? fun op ->
+  Incremental.add_operation inc op >>=? fun inc ->
+  Op.transaction ~gas_limit ~fee:Tez.one (I inc) c2 c1 Tez.one >>=? fun op ->
+  Incremental.add_operation inc op >>=? fun inc ->
+  (* Cook transactions for actual test *)
+  Op.transaction ~gas_limit ~fee:Tez.one (I inc) c1 c2 Tez.one >>=? fun op1 ->
+  Op.transaction ~gas_limit ~fee:Tez.one (I inc) c1 c2 Tez.one >>=? fun op2 ->
+  Op.transaction ~gas_limit ~fee:Tez.one (I inc) c1 c2 Tez.one >>=? fun op3 ->
+  Op.transaction ~gas_limit ~fee:Tez.one (I inc) c2 c1 Tez.one
+  >>=? fun spurious_operation ->
+  let operations = [op1; op2; op3] in
+  Op.combine_operations ~spurious_operation ~source:c1 (I inc) operations
+  >>=? fun operation ->
+  let expect_apply_failure = function
+    | Environment.Ecoproto_error err :: _ ->
+        Assert.test_error_encodings err ;
+        let error_info =
+          Error_monad.find_info_of_error (Environment.wrap_tzerror err)
+        in
+        if error_info.title = "Inconsistent sources in operation pack" then
+          return_unit
+        else failwith "unexpected error"
+    | _ ->
+        failwith
+          "Packed operation has invalid source in the middle : operation \
+           expected to fail."
+  in
+  Incremental.add_operation ~expect_apply_failure inc operation >>=? fun _inc ->
+  return_unit
 
 let expect_inconsistent_counters list =
   if
@@ -339,10 +317,7 @@ let expect_inconsistent_counters list =
       list
 
 let test_inconsistent_counters () =
-  Context.init 2 >>=? fun (blk, contracts) ->
-  let (c1, c2) =
-    match contracts with [c1; c2] -> (c1, c2) | _ -> assert false
-  in
+  Context.init2 () >>=? fun (blk, (c1, c2)) ->
   Op.transaction ~gas_limit ~fee:Tez.one (B blk) c1 c2 Tez.one >>=? fun op1 ->
   Op.transaction ~gas_limit ~fee:Tez.one (B blk) c2 c1 Tez.one >>=? fun op2 ->
   Incremental.begin_construction blk >>=? fun inc ->
diff --git a/src/proto_alpha/lib_protocol/test/integration/operations/test_failing_noop.ml b/src/proto_alpha/lib_protocol/test/integration/operations/test_failing_noop.ml
index 8a7c8efe0f1f..95bd9ea38a68 100644
--- a/src/proto_alpha/lib_protocol/test/integration/operations/test_failing_noop.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/operations/test_failing_noop.ml
@@ -40,16 +40,9 @@
 open Protocol
 open Alpha_context
 
-let register_one_contract () =
-  Context.init 1 >>=? fun (b, contracts) ->
-  let contract =
-    List.nth contracts 0 |> WithExceptions.Option.get ~loc:__LOC__
-  in
-  return (b, contract)
-
 (** try to apply a failing_noop and assert that the operation fails *)
 let failing_noop_must_fail_when_injected () =
-  register_one_contract () >>=? fun (blk, contract) ->
+  Context.init1 () >>=? fun (blk, contract) ->
   Contract.is_implicit contract |> function
   | None -> Alcotest.fail "only implicit accounts can sign"
   | Some source ->
diff --git a/src/proto_alpha/lib_protocol/test/integration/operations/test_origination.ml b/src/proto_alpha/lib_protocol/test/integration/operations/test_origination.ml
index 3d9a6a7c4704..17059e11c40f 100644
--- a/src/proto_alpha/lib_protocol/test/integration/operations/test_origination.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/operations/test_origination.ml
@@ -65,11 +65,7 @@ let total_fees_for_origination ?(fee = Tez.zero) ?(credit = Tez.zero) b =
      fees instantaneously. So to see that the fees are subtracted, we need that
      the bake is done by another delegated. *)
 let test_origination_balances ~loc:_ ?(fee = Tez.zero) ?(credit = Tez.zero) () =
-  Context.init 2 >>=? fun (b, contracts) ->
-  let source = WithExceptions.Option.get ~loc:__LOC__ @@ List.hd contracts in
-  let contract_for_bake =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.nth contracts 1
-  in
+  Context.init2 () >>=? fun (b, (source, contract_for_bake)) ->
   Context.Contract.pkh source >>=? fun pkh_for_orig ->
   Context.Contract.pkh contract_for_bake >>=? fun pkh_for_bake ->
   Op.contract_origination (B b) source ~fee ~credit ~script:Op.dummy_script
@@ -98,11 +94,7 @@ let test_origination_balances ~loc:_ ?(fee = Tez.zero) ?(credit = Tez.zero) () =
     meaning that this contract is spendable; delegatable default is
     set to true meaning that this contract is able to delegate. *)
 let register_origination ?(fee = Tez.zero) ?(credit = Tez.zero) () =
-  Context.init 2 >>=? fun (b, contracts) ->
-  let source = WithExceptions.Option.get ~loc:__LOC__ @@ List.hd contracts in
-  let contract_for_bake =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.nth contracts 1
-  in
+  Context.init2 () >>=? fun (b, (source, contract_for_bake)) ->
   Context.Contract.pkh source >>=? fun source_pkh ->
   Context.Contract.pkh contract_for_bake >>=? fun pkh_for_bake ->
   Op.contract_origination (B b) source ~fee ~credit ~script:Op.dummy_script
@@ -158,13 +150,7 @@ let test_pay_fee () =
 (** Create an originate contract where the contract does not have
     enough tez to pay for the fee. *)
 let test_not_tez_in_contract_to_pay_fee () =
-  Context.init 2 >>=? fun (b, contracts) ->
-  let contract_1 =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.nth contracts 0
-  in
-  let contract_2 =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.nth contracts 1
-  in
+  Context.init2 () >>=? fun (b, (contract_1, contract_2)) ->
   Incremental.begin_construction b >>=? fun inc ->
   (* transfer everything but one tez from 1 to 2 and check balance of 1 *)
   Context.Contract.balance (I inc) contract_1 >>=? fun balance ->
@@ -188,8 +174,7 @@ let test_not_tez_in_contract_to_pay_fee () =
 (* Set the endorser of the block as manager/delegate of the originated
    account. *)
 let register_contract_get_endorser () =
-  Context.init 1 >>=? fun (b, contracts) ->
-  let contract = WithExceptions.Option.get ~loc:__LOC__ @@ List.hd contracts in
+  Context.init1 () >>=? fun (b, contract) ->
   Incremental.begin_construction b >>=? fun inc ->
   Context.get_endorser (I inc) >|=? fun (account_endorser, _slots) ->
   (inc, contract, account_endorser)
@@ -210,8 +195,7 @@ let test_multiple_originations () =
 
 (** Cannot originate two contracts with the same context's counter. *)
 let test_counter () =
-  Context.init 1 >>=? fun (b, contracts) ->
-  let contract = WithExceptions.Option.get ~loc:__LOC__ @@ List.hd contracts in
+  Context.init1 () >>=? fun (b, contract) ->
   Incremental.begin_construction b >>=? fun inc ->
   Op.contract_origination
     (I inc)
diff --git a/src/proto_alpha/lib_protocol/test/integration/operations/test_reveal.ml b/src/proto_alpha/lib_protocol/test/integration/operations/test_reveal.ml
index 7af3e8f9fbbc..7235c59d19d1 100644
--- a/src/proto_alpha/lib_protocol/test/integration/operations/test_reveal.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/operations/test_reveal.ml
@@ -41,8 +41,7 @@ open Test_tez
 let ten_tez = of_int 10
 
 let test_simple_reveal () =
-  Context.init ~consensus_threshold:0 1 >>=? fun (blk, contracts) ->
-  let c = WithExceptions.Option.get ~loc:__LOC__ @@ List.hd contracts in
+  Context.init1 ~consensus_threshold:0 () >>=? fun (blk, c) ->
   let new_c = Account.new_account () in
   let new_contract = Alpha_context.Contract.implicit_contract new_c.pkh in
   (* Create the contract *)
@@ -60,8 +59,7 @@ let test_simple_reveal () =
   | false -> Stdlib.failwith "New contract revelation failed."
 
 let test_empty_account_on_reveal () =
-  Context.init ~consensus_threshold:0 1 >>=? fun (blk, contracts) ->
-  let c = WithExceptions.Option.get ~loc:__LOC__ @@ List.hd contracts in
+  Context.init1 ~consensus_threshold:0 () >>=? fun (blk, c) ->
   let new_c = Account.new_account () in
   let new_contract = Alpha_context.Contract.implicit_contract new_c.pkh in
   let amount = Tez.one_mutez in
@@ -82,8 +80,7 @@ let test_empty_account_on_reveal () =
   | true -> Stdlib.failwith "Empty account still exists and is revealed."
 
 let test_not_enough_found_for_reveal () =
-  Context.init 1 >>=? fun (blk, contracts) ->
-  let c = WithExceptions.Option.get ~loc:__LOC__ @@ List.hd contracts in
+  Context.init1 () >>=? fun (blk, c) ->
   let new_c = Account.new_account () in
   let new_contract = Alpha_context.Contract.implicit_contract new_c.pkh in
   (* Create the contract *)
@@ -99,8 +96,7 @@ let test_not_enough_found_for_reveal () =
   Assert.proto_error_with_info ~loc:__LOC__ res "Balance too low"
 
 let test_transfer_fees_emptying_after_reveal_batched () =
-  Context.init 1 >>=? fun (blk, contracts) ->
-  let c = WithExceptions.Option.get ~loc:__LOC__ @@ List.hd contracts in
+  Context.init1 () >>=? fun (blk, c) ->
   let new_c = Account.new_account () in
   let new_contract = Alpha_context.Contract.implicit_contract new_c.pkh in
   (* Create the contract *)
diff --git a/src/proto_alpha/lib_protocol/test/integration/operations/test_sc_rollup.ml b/src/proto_alpha/lib_protocol/test/integration/operations/test_sc_rollup.ml
index 468484621844..cacd247bda80 100644
--- a/src/proto_alpha/lib_protocol/test/integration/operations/test_sc_rollup.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/operations/test_sc_rollup.ml
@@ -57,10 +57,7 @@ let context_init n =
    rollup when the feature flag is deactivated and checks that it
    fails. *)
 let test_disable_feature_flag () =
-  let* (b, contracts) = Context.init 1 in
-  let contract =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.nth contracts 0
-  in
+  let* (b, contract) = Context.init1 () in
   let* i = Incremental.begin_construction b in
   let kind = Sc_rollup.Kind.Example_arith in
   let* (op, _) = Op.sc_rollup_origination (I i) contract kind "" in
diff --git a/src/proto_alpha/lib_protocol/test/integration/operations/test_transfer.ml b/src/proto_alpha/lib_protocol/test/integration/operations/test_transfer.ml
index d84bcbf92392..b658448b9b09 100644
--- a/src/proto_alpha/lib_protocol/test/integration/operations/test_transfer.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/operations/test_transfer.ml
@@ -115,8 +115,7 @@ let test_transfer_zero_tez () =
 
 (** Transfer zero tez from an implicit contract. *)
 let test_transfer_zero_implicit () =
-  Context.init 1 >>=? fun (b, contracts) ->
-  let dest = WithExceptions.Option.get ~loc:__LOC__ @@ List.nth contracts 0 in
+  Context.init1 () >>=? fun (b, dest) ->
   let account = Account.new_account () in
   Incremental.begin_construction b >>=? fun i ->
   let src = Contract.implicit_contract account.Account.pkh in
@@ -126,10 +125,7 @@ let test_transfer_zero_implicit () =
 
 (** Transfer to originated contract. *)
 let test_transfer_to_originate_with_fee () =
-  Context.init 1 >>=? fun (b, contracts) ->
-  let contract =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.nth contracts 0
-  in
+  Context.init1 () >>=? fun (b, contract) ->
   Incremental.begin_construction b >>=? fun b ->
   two_over_n_of_balance b contract 10L >>=? fun fee ->
   (* originated contract, paying a fee to originated this contract *)
@@ -158,10 +154,7 @@ let test_transfer_amount_of_contract_balance () =
 
 (** Transfer to oneself. *)
 let test_transfers_to_self () =
-  Context.init 1 >>=? fun (b, contracts) ->
-  let contract =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.nth contracts 0
-  in
+  Context.init1 () >>=? fun (b, contract) ->
   Incremental.begin_construction b >>=? fun b ->
   two_over_n_of_balance b contract 3L >>=? fun amount ->
   transfer_to_itself_and_check_balances ~loc:__LOC__ b contract amount
@@ -188,8 +181,7 @@ let test_missing_transaction () =
 
 (** Transfer zero tez to an implicit contract, with fee equals balance of src. *)
 let test_transfer_zero_implicit_with_bal_src_as_fee () =
-  Context.init 1 >>=? fun (b, contracts) ->
-  let dest = WithExceptions.Option.get ~loc:__LOC__ @@ List.nth contracts 0 in
+  Context.init1 () >>=? fun (b, dest) ->
   let account = Account.new_account () in
   Incremental.begin_construction b >>=? fun i ->
   let src = Contract.implicit_contract account.Account.pkh in
@@ -203,8 +195,7 @@ let test_transfer_zero_implicit_with_bal_src_as_fee () =
 
 (** Transfer zero tez to an originated contract, with fee equals balance of src. *)
 let test_transfer_zero_to_originated_with_bal_src_as_fee () =
-  Context.init 1 >>=? fun (b, contracts) ->
-  let dest = WithExceptions.Option.get ~loc:__LOC__ @@ List.nth contracts 0 in
+  Context.init1 () >>=? fun (b, dest) ->
   let account = Account.new_account () in
   Incremental.begin_construction b >>=? fun i ->
   let src = Contract.implicit_contract account.Account.pkh in
@@ -221,8 +212,7 @@ let test_transfer_zero_to_originated_with_bal_src_as_fee () =
 
 (** Transfer one tez to an implicit contract, with fee equals balance of src. *)
 let test_transfer_one_to_implicit_with_bal_src_as_fee () =
-  Context.init 1 >>=? fun (b, contracts) ->
-  let dest = WithExceptions.Option.get ~loc:__LOC__ @@ List.nth contracts 0 in
+  Context.init1 () >>=? fun (b, dest) ->
   let account = Account.new_account () in
   Incremental.begin_construction b >>=? fun i ->
   let src = Contract.implicit_contract account.Account.pkh in
@@ -245,10 +235,7 @@ let test_transfer_one_to_implicit_with_bal_src_as_fee () =
 
 (** Implicit to Implicit. *)
 let test_transfer_from_implicit_to_implicit_contract () =
-  Context.init 1 >>=? fun (b, contracts) ->
-  let bootstrap_contract =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.nth contracts 0
-  in
+  Context.init1 () >>=? fun (b, bootstrap_contract) ->
   let account_a = Account.new_account () in
   let account_b = Account.new_account () in
   Incremental.begin_construction b >>=? fun b ->
@@ -282,13 +269,8 @@ let test_transfer_from_implicit_to_implicit_contract () =
 
 (** Implicit to originated. *)
 let test_transfer_from_implicit_to_originated_contract () =
-  Context.init 1 >>=? fun (b, contracts) ->
-  let bootstrap_contract =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.nth contracts 0
-  in
-  let contract =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.nth contracts 0
-  in
+  Context.init1 () >>=? fun (b, bootstrap_contract) ->
+  let contract = bootstrap_contract in
   let account = Account.new_account () in
   let src = Contract.implicit_contract account.Account.pkh in
   Incremental.begin_construction b >>=? fun b ->
@@ -339,7 +321,7 @@ let test_block_with_multiple_transfers_pay_fee () =
     2- Apply multiple transfers without fees;
     3- Apply multiple transfers with fees. *)
 let test_block_with_multiple_transfers_with_without_fee () =
-  Context.init 8 >>=? fun (b, contracts) ->
+  Context.init_n 8 () >>=? fun (b, contracts) ->
   let contracts = Array.of_list contracts in
   Incremental.begin_construction b >>=? fun b ->
   let hundred = of_int 100 in
@@ -383,8 +365,7 @@ let test_build_a_chain () =
 
 (** Transferring zero tez is forbidden in implicit contract. *)
 let test_empty_implicit () =
-  Context.init 1 >>=? fun (b, contracts) ->
-  let dest = WithExceptions.Option.get ~loc:__LOC__ @@ List.nth contracts 0 in
+  Context.init1 () >>=? fun (b, dest) ->
   let account = Account.new_account () in
   Incremental.begin_construction b >>=? fun incr ->
   let src = Contract.implicit_contract account.Account.pkh in
@@ -431,16 +412,7 @@ let test_balance_too_low fee () =
     3- Add another transfer that send tez from a zero balance contract;
     4- Catch the expected error: Balance_too_low. *)
 let test_balance_too_low_two_transfers fee () =
-  Context.init 3 >>=? fun (b, contracts) ->
-  let contract_1 =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.nth contracts 0
-  in
-  let contract_2 =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.nth contracts 1
-  in
-  let contract_3 =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.nth contracts 2
-  in
+  Context.init3 () >>=? fun (b, (contract_1, contract_2, contract_3)) ->
   Incremental.begin_construction b >>=? fun i ->
   Context.Contract.balance (I i) contract_1 >>=? fun balance ->
   balance /? 3L >>?= fun res ->
@@ -545,7 +517,7 @@ let random_contract contract_array =
 (** Transfer by randomly choose amount 10 contracts, and randomly
     choose the amount in the source contract. *)
 let test_random_transfer () =
-  Context.init 10 >>=? fun (b, contracts) ->
+  Context.init_n 10 () >>=? fun (b, contracts) ->
   let contracts = Array.of_list contracts in
   let source = random_contract contracts in
   let dest = random_contract contracts in
@@ -569,7 +541,7 @@ let test_random_multi_transactions () =
 (*********************************************************************)
 
 let test_bad_entrypoint () =
-  Context.init 1 >>=? fun (b, _cs) ->
+  Context.init1 () >>=? fun (b, _c) ->
   Incremental.begin_construction b >>=? fun v ->
   let ctxt = Incremental.alpha_ctxt v in
   let storage = "Unit" in
@@ -596,7 +568,7 @@ let test_bad_entrypoint () =
       Alcotest.failf "Unexpected error: %a" Error_monad.pp_print_trace errs
 
 let test_bad_parameter () =
-  Context.init 1 >>=? fun (b, _cs) ->
+  Context.init1 () >>=? fun (b, _c) ->
   Incremental.begin_construction b >>=? fun v ->
   let ctxt = Incremental.alpha_ctxt v in
   let storage = "Unit" in
@@ -623,9 +595,8 @@ let test_bad_parameter () =
 
 let transfer_to_itself_with_no_such_entrypoint () =
   let entrypoint = Entrypoint.of_string_strict_exn "bad entrypoint" in
-  Context.init 1 >>=? fun (b, contract) ->
+  Context.init1 () >>=? fun (b, addr) ->
   Incremental.begin_construction b >>=? fun i ->
-  let addr = match contract with [hd] -> hd | _ -> assert false in
   Op.transaction (B b) addr addr Tez.one ~entrypoint >>=? fun transaction ->
   let expect_failure = function
     | Environment.Ecoproto_error (Script_tc_errors.No_such_entrypoint _ as e)
diff --git a/src/proto_alpha/lib_protocol/test/integration/operations/test_tx_rollup.ml b/src/proto_alpha/lib_protocol/test/integration/operations/test_tx_rollup.ml
index d6c21dec0270..635a8b8ee993 100644
--- a/src/proto_alpha/lib_protocol/test/integration/operations/test_tx_rollup.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/operations/test_tx_rollup.ml
@@ -612,11 +612,8 @@ let message_result context_hash withdraws =
 (** [test_origination] originates a transaction rollup and checks that
     it burns the expected quantity of xtz. *)
 let test_origination () =
-  Context.init ~tx_rollup_enable:true ~tx_rollup_sunset_level:Int32.max_int 1
-  >>=? fun (b, contracts) ->
-  let contract =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.nth contracts 0
-  in
+  Context.init1 ~tx_rollup_enable:true ~tx_rollup_sunset_level:Int32.max_int ()
+  >>=? fun (b, contract) ->
   Context.get_constants (B b)
   >>=? fun {parametric = {tx_rollup_origination_size; cost_per_byte; _}; _} ->
   Context.Contract.balance (B b) contract >>=? fun balance ->
@@ -636,11 +633,8 @@ let test_origination () =
 (** [test_two_originations] originates two transaction rollups in the
     same operation and checks that they have a different address. *)
 let test_two_originations () =
-  Context.init ~tx_rollup_enable:true ~tx_rollup_sunset_level:Int32.max_int 1
-  >>=? fun (b, contracts) ->
-  let contract =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.nth contracts 0
-  in
+  Context.init1 ~tx_rollup_enable:true ~tx_rollup_sunset_level:Int32.max_int ()
+  >>=? fun (b, contract) ->
   Incremental.begin_construction b >>=? fun i ->
   Op.tx_rollup_origination (I i) contract >>=? fun (op1, _false_tx_rollup1) ->
   (* tx_rollup1 and tx_rollup2 are equal and both are false. The addresses are
diff --git a/src/proto_alpha/lib_protocol/test/integration/operations/test_voting.ml b/src/proto_alpha/lib_protocol/test/integration/operations/test_voting.ml
index 57bbc0be0300..2e68b6853558 100644
--- a/src/proto_alpha/lib_protocol/test/integration/operations/test_voting.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/operations/test_voting.ml
@@ -235,7 +235,7 @@ let context_init =
      `blocks_per_voting_period <= preserved_cycles * blocks_per_cycle.`
      We also set baking and endorsing rewards to zero in order to
      ease accounting of exact baker stake. *)
-  Context.init
+  Context.init_n
     ~blocks_per_cycle:4l
     ~cycles_per_voting_period:1l
     ~consensus_threshold:0
@@ -247,7 +247,7 @@ let context_init =
 let test_successful_vote num_delegates () =
   let open Alpha_context in
   let min_proposal_quorum = Int32.(of_int @@ (100_00 / num_delegates)) in
-  context_init ~min_proposal_quorum num_delegates >>=? fun (b, _) ->
+  context_init ~min_proposal_quorum num_delegates () >>=? fun (b, _) ->
   (* no ballots in proposal period *)
   assert_empty_ballots b __LOC__ >>=? fun () ->
   (* Last baked block is first block of period Proposal *)
@@ -482,7 +482,7 @@ let get_expected_participation_ema power voter_power old_participation_ema =
     in exploration, go back to proposal period. *)
 let test_not_enough_quorum_in_exploration num_delegates () =
   let min_proposal_quorum = Int32.(of_int @@ (100_00 / num_delegates)) in
-  context_init ~min_proposal_quorum num_delegates >>=? fun (b, delegates) ->
+  context_init ~min_proposal_quorum num_delegates () >>=? fun (b, delegates) ->
   (* proposal period *)
   let open Alpha_context in
   assert_period ~expected_kind:Proposal b __LOC__ >>=? fun () ->
@@ -538,7 +538,7 @@ let test_not_enough_quorum_in_exploration num_delegates () =
    In promotion period, go back to proposal period. *)
 let test_not_enough_quorum_in_promotion num_delegates () =
   let min_proposal_quorum = Int32.(of_int @@ (100_00 / num_delegates)) in
-  context_init ~min_proposal_quorum num_delegates >>=? fun (b, delegates) ->
+  context_init ~min_proposal_quorum num_delegates () >>=? fun (b, delegates) ->
   assert_period ~expected_kind:Proposal b __LOC__ >>=? fun () ->
   let proposer =
     WithExceptions.Option.get ~loc:__LOC__ @@ List.nth delegates 0
@@ -612,7 +612,7 @@ let test_not_enough_quorum_in_promotion num_delegates () =
 (** Identical proposals (identified by their hash) must be counted as
     one. *)
 let test_multiple_identical_proposals_count_as_one () =
-  context_init 1 >>=? fun (b, delegates) ->
+  context_init 1 () >>=? fun (b, delegates) ->
   assert_period ~expected_kind:Proposal b __LOC__ >>=? fun () ->
   let proposer = WithExceptions.Option.get ~loc:__LOC__ @@ List.hd delegates in
   Op.proposals (B b) proposer [Protocol_hash.zero; Protocol_hash.zero]
@@ -640,7 +640,7 @@ let test_multiple_identical_proposals_count_as_one () =
           expected_weight_proposer
   | None -> failwith "%s - Missing proposal" __LOC__
 
-(** Assume the initial balance of accounts allocated by Context.init is at
+(** Assume the initial balance of accounts allocated by Context.init_n is at
     least 4 times the value of the tokens_per_roll constant. *)
 let test_supermajority_in_proposal there_is_a_winner () =
   let min_proposal_quorum = 0l in
@@ -649,6 +649,7 @@ let test_supermajority_in_proposal there_is_a_winner () =
     ~min_proposal_quorum
     ~initial_balances:[initial_balance; initial_balance; initial_balance]
     10
+    ()
   >>=? fun (b, delegates) ->
   Context.get_constants (B b) >>=? fun {parametric = {tokens_per_roll; _}; _} ->
   let del1 = WithExceptions.Option.get ~loc:__LOC__ @@ List.nth delegates 0 in
@@ -700,7 +701,7 @@ let test_supermajority_in_proposal there_is_a_winner () =
 let test_quorum_in_proposal has_quorum () =
   let total_tokens = 32_000_000_000_000L in
   let half_tokens = Int64.div total_tokens 2L in
-  context_init ~initial_balances:[1L; half_tokens; half_tokens] 3
+  context_init ~initial_balances:[1L; half_tokens; half_tokens] 3 ()
   >>=? fun (b, delegates) ->
   Context.get_constants (B b)
   >>=? fun {parametric = {min_proposal_quorum; _}; _} ->
@@ -733,7 +734,7 @@ let test_quorum_in_proposal has_quorum () =
     reached. Otherwise, it remains in proposal period. *)
 let test_supermajority_in_exploration supermajority () =
   let min_proposal_quorum = Int32.(of_int @@ (100_00 / 100)) in
-  context_init ~min_proposal_quorum 100 >>=? fun (b, delegates) ->
+  context_init ~min_proposal_quorum 100 () >>=? fun (b, delegates) ->
   let del1 = WithExceptions.Option.get ~loc:__LOC__ @@ List.nth delegates 0 in
   let proposal = protos.(0) in
   Op.proposals (B b) del1 [proposal] >>=? fun ops1 ->
@@ -777,7 +778,7 @@ let test_supermajority_in_exploration supermajority () =
     proposals. *)
 let test_no_winning_proposal num_delegates () =
   let min_proposal_quorum = Int32.(of_int @@ (100_00 / num_delegates)) in
-  context_init ~min_proposal_quorum num_delegates >>=? fun (b, _) ->
+  context_init ~min_proposal_quorum num_delegates () >>=? fun (b, _) ->
   (* beginning of proposal, denoted by _p1;
      take a snapshot of the active delegates and their voting power from listings *)
   get_delegates_and_power_from_listings b >>=? fun (delegates_p1, _power_p1) ->
@@ -799,7 +800,7 @@ let test_no_winning_proposal num_delegates () =
     maximum quorum cap. *)
 let test_quorum_capped_maximum num_delegates () =
   let min_proposal_quorum = Int32.(of_int @@ (100_00 / num_delegates)) in
-  context_init ~min_proposal_quorum num_delegates >>=? fun (b, delegates) ->
+  context_init ~min_proposal_quorum num_delegates () >>=? fun (b, delegates) ->
   (* set the participation EMA to 100% *)
   Context.Vote.set_participation_ema b 100_00l >>= fun b ->
   Context.get_constants (B b) >>=? fun {parametric = {quorum_max; _}; _} ->
@@ -839,7 +840,7 @@ let test_quorum_capped_maximum num_delegates () =
     minimum quorum cap. *)
 let test_quorum_capped_minimum num_delegates () =
   let min_proposal_quorum = Int32.(of_int @@ (100_00 / num_delegates)) in
-  context_init ~min_proposal_quorum num_delegates >>=? fun (b, delegates) ->
+  context_init ~min_proposal_quorum num_delegates () >>=? fun (b, delegates) ->
   (* set the participation EMA to 0% *)
   Context.Vote.set_participation_ema b 0l >>= fun b ->
   Context.get_constants (B b) >>=? fun {parametric = {quorum_min; _}; _} ->
@@ -888,7 +889,7 @@ let test_voting_power_updated_each_voting_period () =
   let init_bal2 = 48_000_000_000L in
   let init_bal3 = 40_000_000_000L in
   (* Create three accounts with different amounts *)
-  context_init ~initial_balances:[init_bal1; init_bal2; init_bal3] 3
+  context_init ~initial_balances:[init_bal1; init_bal2; init_bal3] 3 ()
   >>=? fun (genesis, contracts) ->
   let con1 = WithExceptions.Option.get ~loc:__LOC__ @@ List.nth contracts 0 in
   let con2 = WithExceptions.Option.get ~loc:__LOC__ @@ List.nth contracts 1 in
diff --git a/src/proto_alpha/lib_protocol/test/integration/test_frozen_bonds.ml b/src/proto_alpha/lib_protocol/test/integration/test_frozen_bonds.ml
index 47b223b4067c..8e5af11ece3b 100644
--- a/src/proto_alpha/lib_protocol/test/integration/test_frozen_bonds.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/test_frozen_bonds.ml
@@ -308,16 +308,13 @@ let test_total_stake ~user_is_delegate () =
     These rpcs call the functions [Contract.get_frozen_bonds] and
     [Contract.get_balance_and_frozen_bonds] already tested in previous tests. *)
 let test_rpcs () =
-  Context.init 1 >>=? fun (blk, contracts) ->
-  match contracts with
-  | [contract] ->
-      Context.Contract.frozen_bonds (B blk) contract >>=? fun frozen_bonds ->
-      Assert.equal_tez ~loc:__LOC__ frozen_bonds Tez.zero >>=? fun () ->
-      Context.Contract.balance_and_frozen_bonds (B blk) contract
-      >>=? fun balance_and_frozen_bonds ->
-      Context.Contract.balance (B blk) contract >>=? fun balance ->
-      Assert.equal_tez ~loc:__LOC__ balance_and_frozen_bonds balance
-  | _ -> (* Exactly one account has been generated. *) assert false
+  Context.init1 () >>=? fun (blk, contract) ->
+  Context.Contract.frozen_bonds (B blk) contract >>=? fun frozen_bonds ->
+  Assert.equal_tez ~loc:__LOC__ frozen_bonds Tez.zero >>=? fun () ->
+  Context.Contract.balance_and_frozen_bonds (B blk) contract
+  >>=? fun balance_and_frozen_bonds ->
+  Context.Contract.balance (B blk) contract >>=? fun balance ->
+  Assert.equal_tez ~loc:__LOC__ balance_and_frozen_bonds balance
 
 (** A helper to test a particular delegation/freezing scenario *)
 let test_scenario scenario =
diff --git a/src/proto_alpha/lib_protocol/test/integration/test_liquidity_baking.ml b/src/proto_alpha/lib_protocol/test/integration/test_liquidity_baking.ml
index 0e1e98d69524..5eb5f12b0e22 100644
--- a/src/proto_alpha/lib_protocol/test/integration/test_liquidity_baking.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/test_liquidity_baking.ml
@@ -71,7 +71,7 @@ let expected_lqt_hash =
 
 (* Test that the scripts of the Liquidity Baking contracts (CPMM and LQT) have the expected hashes. *)
 let liquidity_baking_origination () =
-  Context.init 1 >>=? fun (blk, _contracts) ->
+  Context.init1 () >>=? fun (blk, _contract) ->
   Context.get_liquidity_baking_cpmm_address (B blk) >>=? fun cpmm_address ->
   Context.Contract.script_hash (B blk) cpmm_address >>=? fun cpmm_hash ->
   Lwt.return @@ Environment.wrap_tzresult
@@ -97,7 +97,7 @@ let liquidity_baking_origination () =
 
 (* Test that the CPMM address in storage is correct *)
 let liquidity_baking_cpmm_address () =
-  Context.init 1 >>=? fun (blk, _contracts) ->
+  Context.init1 () >>=? fun (blk, _contract) ->
   Context.get_liquidity_baking_cpmm_address (B blk) >>=? fun liquidity_baking ->
   Assert.equal
     ~loc:__LOC__
@@ -110,7 +110,7 @@ let liquidity_baking_cpmm_address () =
 
 (* Test that after [n] blocks, the liquidity baking CPMM contract is credited [n] times the subsidy amount. *)
 let liquidity_baking_subsidies n () =
-  Context.init ~consensus_threshold:0 1 >>=? fun (blk, _contracts) ->
+  Context.init1 ~consensus_threshold:0 () >>=? fun (blk, _contract) ->
   Context.get_liquidity_baking_cpmm_address (B blk) >>=? fun liquidity_baking ->
   Context.Contract.balance (B blk) liquidity_baking >>=? fun old_balance ->
   Block.bake_n n blk >>=? fun blk ->
@@ -129,7 +129,7 @@ let liquidity_baking_subsidies n () =
    More precisely, after the sunset, the total amount credited to the subsidy is only proportional
    to the sunset level and in particular it does not depend on [n]. *)
 let liquidity_baking_sunset_level n () =
-  Context.init ~consensus_threshold:0 1 >>=? fun (blk, _contracts) ->
+  Context.init1 ~consensus_threshold:0 () >>=? fun (blk, _contract) ->
   Context.get_liquidity_baking_cpmm_address (B blk) >>=? fun liquidity_baking ->
   Context.get_constants (B blk) >>=? fun csts ->
   let sunset = csts.parametric.liquidity_baking_sunset_level in
@@ -152,7 +152,7 @@ let liquidity_baking_sunset_level n () =
 (* Expected level is roughly 2*(log(1-1/(2*p)) / log(0.999)) where [p] is the proportion [LB_off / (LB_on + LB_off)]. *)
 let liquidity_baking_toggle ~n_vote_on ~n_vote_off ~n_vote_pass expected_level
     bake_after () =
-  Context.init ~consensus_threshold:0 1 >>=? fun (blk, _contracts) ->
+  Context.init1 ~consensus_threshold:0 () >>=? fun (blk, _contract) ->
   Context.get_liquidity_baking_cpmm_address (B blk) >>=? fun liquidity_baking ->
   Context.Contract.balance (B blk) liquidity_baking >>=? fun old_balance ->
   Context.get_liquidity_baking_subsidy (B blk)
@@ -198,7 +198,7 @@ let liquidity_baking_toggle_60 n () =
 (* 50% of blocks have liquidity_baking_toggle_vote = LB_off.
    Subsidy should not be stopped. *)
 let liquidity_baking_toggle_50 n () =
-  Context.init ~consensus_threshold:0 1 >>=? fun (blk, _contracts) ->
+  Context.init1 ~consensus_threshold:0 () >>=? fun (blk, _contract) ->
   Context.get_liquidity_baking_cpmm_address (B blk) >>=? fun liquidity_baking ->
   Context.get_constants (B blk) >>=? fun csts ->
   let sunset = csts.parametric.liquidity_baking_sunset_level in
@@ -228,7 +228,7 @@ let liquidity_baking_toggle_50 n () =
    n_votes with LB_on, check that the subsidy flows.
  *)
 let liquidity_baking_restart n_votes n () =
-  Context.init ~consensus_threshold:0 1 >>=? fun (blk, _contracts) ->
+  Context.init1 ~consensus_threshold:0 () >>=? fun (blk, _contract) ->
   Context.get_liquidity_baking_cpmm_address (B blk) >>=? fun liquidity_baking ->
   Block.bake_n ~liquidity_baking_toggle_vote:LB_off n_votes blk >>=? fun blk ->
   Context.Contract.balance (B blk) liquidity_baking
@@ -254,7 +254,7 @@ let liquidity_baking_restart n_votes n () =
 (* Test that the toggle EMA in block metadata is correct. *)
 let liquidity_baking_toggle_ema n_vote_on n_vote_off level bake_after
     expected_toggle_ema () =
-  Context.init ~consensus_threshold:0 1 >>=? fun (blk, _contracts) ->
+  Context.init1 ~consensus_threshold:0 () >>=? fun (blk, _contract) ->
   let rec bake_escaping blk i =
     if i < level then
       Block.bake_n ~liquidity_baking_toggle_vote:LB_on n_vote_on blk
@@ -283,7 +283,7 @@ let liquidity_baking_toggle_ema_threshold () =
   liquidity_baking_toggle_ema 0 1 1386 1 1_001_000_000 ()
 
 let liquidity_baking_storage n () =
-  Context.init ~consensus_threshold:0 1 >>=? fun (blk, _contracts) ->
+  Context.init1 ~consensus_threshold:0 () >>=? fun (blk, _contract) ->
   Context.get_liquidity_baking_cpmm_address (B blk) >>=? fun liquidity_baking ->
   Context.get_liquidity_baking_subsidy (B blk) >>=? fun subsidy ->
   let expected_storage =
@@ -311,7 +311,7 @@ let liquidity_baking_storage n () =
   >>=? fun () -> return_unit
 
 let liquidity_baking_balance_update () =
-  Context.init ~consensus_threshold:0 1 >>=? fun (blk, _contracts) ->
+  Context.init1 ~consensus_threshold:0 () >>=? fun (blk, _contract) ->
   Context.get_liquidity_baking_cpmm_address (B blk) >>=? fun liquidity_baking ->
   Context.get_constants (B blk) >>=? fun csts ->
   let sunset = csts.parametric.liquidity_baking_sunset_level in
@@ -370,7 +370,7 @@ let get_balance_update_in_result result =
   | _ -> assert false
 
 let liquidity_baking_origination_result_cpmm_address () =
-  Context.init 1 >>=? fun (blk, _contracts) ->
+  Context.init1 () >>=? fun (blk, _contract) ->
   Context.get_liquidity_baking_cpmm_address (B blk)
   >>=? fun cpmm_address_in_storage ->
   Block.bake_n_with_origination_results 1 blk
@@ -387,7 +387,7 @@ let liquidity_baking_origination_result_cpmm_address () =
   >>=? fun () -> return_unit
 
 let liquidity_baking_origination_result_cpmm_balance () =
-  Context.init 1 >>=? fun (blk, _contracts) ->
+  Context.init1 () >>=? fun (blk, _contract) ->
   Block.bake_n_with_origination_results 1 blk
   >>=? fun (_blk, origination_results) ->
   let result = get_cpmm_result origination_results in
@@ -396,7 +396,7 @@ let liquidity_baking_origination_result_cpmm_balance () =
   >>=? fun () -> return_unit
 
 let liquidity_baking_origination_result_lqt_address () =
-  Context.init 1 >>=? fun (blk, _contracts) ->
+  Context.init1 () >>=? fun (blk, _contract) ->
   Block.bake_n_with_origination_results 1 blk
   >>=? fun (_blk, origination_results) ->
   let result = get_lqt_result origination_results in
@@ -411,7 +411,7 @@ let liquidity_baking_origination_result_lqt_address () =
   >>=? fun () -> return_unit
 
 let liquidity_baking_origination_result_lqt_balance () =
-  Context.init 1 >>=? fun (blk, _contracts) ->
+  Context.init1 () >>=? fun (blk, _contract) ->
   Block.bake_n_with_origination_results 1 blk
   >>=? fun (_blk, origination_results) ->
   let result = get_lqt_result origination_results in
@@ -431,7 +431,7 @@ let liquidity_baking_origination_result_lqt_balance () =
 
 (* Test that with no contract at the tzBTC address and the level low enough to indicate we're not on mainnet, three contracts are originated in stitching. *)
 let liquidity_baking_origination_test_migration () =
-  Context.init 1 >>=? fun (blk, _contracts) ->
+  Context.init1 () >>=? fun (blk, _contract) ->
   Block.bake_n_with_origination_results 1 blk
   >>=? fun (_blk, origination_results) ->
   let num_results = List.length origination_results in
@@ -439,8 +439,8 @@ let liquidity_baking_origination_test_migration () =
 
 (* Test that with no contract at the tzBTC address and the level high enough to indicate we could be on mainnet, no contracts are originated in stitching. *)
 let liquidity_baking_origination_no_tzBTC_mainnet_migration () =
-  Context.init ~consensus_threshold:0 ~level:1_437_862l 1
-  >>=? fun (blk, _contracts) ->
+  Context.init1 ~consensus_threshold:0 ~level:1_437_862l ()
+  >>=? fun (blk, _contract) ->
   (* By baking a bit we also check that the subsidy application with no CPMM present does nothing rather than stopping the chain.*)
   Block.bake_n_with_origination_results 64 blk
   >>=? fun (_blk, origination_results) ->
diff --git a/src/proto_alpha/lib_protocol/test/pbt/test_carbonated_map.ml b/src/proto_alpha/lib_protocol/test/pbt/test_carbonated_map.ml
index e0a588968a30..030c6fea96ef 100644
--- a/src/proto_alpha/lib_protocol/test/pbt/test_carbonated_map.ml
+++ b/src/proto_alpha/lib_protocol/test/pbt/test_carbonated_map.ml
@@ -39,7 +39,7 @@ let wrap m = m >|= Environment.wrap_tzresult
 
 let new_ctxt () =
   let ( let* ) m f = m >>=? f in
-  let* (block, _) = Context.init 1 in
+  let* (block, _contract) = Context.init1 () in
   let* incr = Incremental.begin_construction block in
   return @@ Incremental.alpha_ctxt incr
 
diff --git a/src/proto_alpha/lib_protocol/test/pbt/test_gas_properties.ml b/src/proto_alpha/lib_protocol/test/pbt/test_gas_properties.ml
index 4eee27d8fca8..13809ed741db 100644
--- a/src/proto_alpha/lib_protocol/test/pbt/test_gas_properties.ml
+++ b/src/proto_alpha/lib_protocol/test/pbt/test_gas_properties.ml
@@ -91,7 +91,7 @@ let test_consume_commutes (start, cost1, cost2) =
 let context_arb : Alpha_context.t QCheck.arbitrary =
   QCheck.always
     (Lwt_main.run
-       ( Context.init 1 >>=? fun (b, _contracts) ->
+       ( Context.init1 () >>=? fun (b, _contract) ->
          Incremental.begin_construction b >|=? fun inc ->
          let state = Incremental.validation_state inc in
          Alpha_context.Gas.set_limit
diff --git a/src/proto_alpha/lib_protocol/test/pbt/test_script_comparison.ml b/src/proto_alpha/lib_protocol/test/pbt/test_script_comparison.ml
index dc0c058730dc..fb74fb9289d5 100644
--- a/src/proto_alpha/lib_protocol/test/pbt/test_script_comparison.ml
+++ b/src/proto_alpha/lib_protocol/test/pbt/test_script_comparison.ml
@@ -202,7 +202,7 @@ let assert_return x = assert_ok (Lwt_main.run x)
 
 let ctxt =
   assert_return
-    ( Context.init 3 >>=? fun (b, _cs) ->
+    ( Context.init3 () >>=? fun (b, _cs) ->
       Incremental.begin_construction b >>=? fun v ->
       return (Incremental.alpha_ctxt v) )
 
diff --git a/src/proto_alpha/lib_protocol/test/unit/test_gas_monad.ml b/src/proto_alpha/lib_protocol/test/unit/test_gas_monad.ml
index 27a82fe49119..31d4dfd25f0b 100644
--- a/src/proto_alpha/lib_protocol/test/unit/test_gas_monad.ml
+++ b/src/proto_alpha/lib_protocol/test/unit/test_gas_monad.ml
@@ -38,7 +38,7 @@ module GM = Gas_monad
 let ten_milligas = Gas.fp_of_milligas_int 10
 
 let new_context ~limit =
-  Context.init 1 >>=? fun (b, _contracts) ->
+  Context.init1 () >>=? fun (b, _contract) ->
   Incremental.begin_construction b >|=? fun inc ->
   let state = Incremental.validation_state inc in
   Gas.set_limit state.ctxt limit
diff --git a/src/proto_alpha/lib_protocol/test/unit/test_sc_rollup_arith.ml b/src/proto_alpha/lib_protocol/test/unit/test_sc_rollup_arith.ml
index 24fe441bc5e4..0ddece927568 100644
--- a/src/proto_alpha/lib_protocol/test/unit/test_sc_rollup_arith.ml
+++ b/src/proto_alpha/lib_protocol/test/unit/test_sc_rollup_arith.ml
@@ -36,7 +36,7 @@ open Sc_rollup_arith.ProtocolImplementation
 open Alpha_context
 
 let create_context () =
-  Context.init 1 >>=? fun (block, _) -> return block.context
+  Context.init1 () >>=? fun (block, _contract) -> return block.context
 
 let setup boot_sector f =
   create_context () >>=? fun ctxt ->
diff --git a/src/proto_alpha/lib_protocol/test/unit/test_sc_rollup_inbox.ml b/src/proto_alpha/lib_protocol/test/unit/test_sc_rollup_inbox.ml
index a822d26016b6..59b777f9fce9 100644
--- a/src/proto_alpha/lib_protocol/test/unit/test_sc_rollup_inbox.ml
+++ b/src/proto_alpha/lib_protocol/test/unit/test_sc_rollup_inbox.ml
@@ -45,7 +45,7 @@ let level =
   Raw_level_repr.of_int32 0l |> function Ok x -> x | _ -> assert false
 
 let create_context () =
-  Context.init 1 >>=? fun (block, _) -> return block.context
+  Context.init1 () >>=? fun (block, _contract) -> return block.context
 
 let test_empty () =
   let inbox = empty rollup level in
diff --git a/src/proto_alpha/lib_protocol/test/unit/test_sc_rollup_storage.ml b/src/proto_alpha/lib_protocol/test/unit/test_sc_rollup_storage.ml
index 7fa91a47bde9..7b689e88cadc 100644
--- a/src/proto_alpha/lib_protocol/test/unit/test_sc_rollup_storage.ml
+++ b/src/proto_alpha/lib_protocol/test/unit/test_sc_rollup_storage.ml
@@ -38,7 +38,7 @@ open Lwt_result_syntax
 let lift k = Lwt.map Environment.wrap_tzresult k
 
 let new_context () =
-  let* (b, _contracts) = Context.init 1 in
+  let* (b, _contract) = Context.init1 () in
   Incremental.begin_construction b >|=? fun inc ->
   let state = Incremental.validation_state inc in
   let ctxt = state.ctxt in
diff --git a/src/proto_alpha/lib_protocol/test/unit/test_tx_rollup_l2.ml b/src/proto_alpha/lib_protocol/test/unit/test_tx_rollup_l2.ml
index ea0e34c2c93e..2255140f8348 100644
--- a/src/proto_alpha/lib_protocol/test/unit/test_tx_rollup_l2.ml
+++ b/src/proto_alpha/lib_protocol/test/unit/test_tx_rollup_l2.ml
@@ -326,7 +326,7 @@ end)
 let gen_n_ticket_hash n =
   let x =
     Lwt_main.run
-      ( Context.init n >>=? fun (_b, contracts) ->
+      ( Context.init_n n () >>=? fun (_b, contracts) ->
         let addressess = gen_n_address n in
         let tickets =
           List.map2
-- 
GitLab


From 2e93155d17d02a43ac0a84dcc727cfa87713c9ea Mon Sep 17 00:00:00 2001
From: Mehdi Bouaziz <mehdi.bouaziz@nomadic-labs.com>
Date: Fri, 8 Apr 2022 19:23:29 +0200
Subject: [PATCH 3/6] Proto/Tests: generalize init with GADT tuple

---
 .../lib_protocol/test/helpers/context.ml      | 39 +++++++++++++------
 1 file changed, 28 insertions(+), 11 deletions(-)

diff --git a/src/proto_alpha/lib_protocol/test/helpers/context.ml b/src/proto_alpha/lib_protocol/test/helpers/context.ml
index f6f4aa2bfd1c..64e5de8f16de 100644
--- a/src/proto_alpha/lib_protocol/test/helpers/context.ml
+++ b/src/proto_alpha/lib_protocol/test/helpers/context.ml
@@ -354,12 +354,34 @@ module Tx_rollup = struct
     Tx_rollup_services.commitment rpc_ctxt ctxt tx_rollup
 end
 
-let init_gen n get ?rng_state ?commitments ?(initial_balances = [])
+type (_, _) tup =
+  | T1 : ('a, 'a) tup
+  | T2 : ('a, 'a * 'a) tup
+  | T3 : ('a, 'a * 'a * 'a) tup
+  | TList : int -> ('a, 'a list) tup
+
+let tup_n : type a r. (a, r) tup -> int = function
+  | T1 -> 1
+  | T2 -> 2
+  | T3 -> 3
+  | TList n -> n
+
+let tup_get : type a r. (a, r) tup -> a list -> r =
+ fun tup list ->
+  match (tup, list) with
+  | (T1, [v]) -> v
+  | (T2, [v1; v2]) -> (v1, v2)
+  | (T3, [v1; v2; v3]) -> (v1, v2, v3)
+  | (TList _, l) -> l
+  | _ -> assert false
+
+let init_gen tup ?rng_state ?commitments ?(initial_balances = [])
     ?consensus_threshold ?min_proposal_quorum ?bootstrap_contracts ?level
     ?cost_per_byte ?liquidity_baking_subsidy ?endorsing_reward_per_slot
     ?baking_reward_bonus_per_slot ?baking_reward_fixed_portion ?origination_size
     ?blocks_per_cycle ?cycles_per_voting_period ?tx_rollup_enable
     ?tx_rollup_sunset_level ?tx_rollup_origination_size ?sc_rollup_enable () =
+  let n = tup_n tup in
   let accounts = Account.generate_accounts ?rng_state ~initial_balances n in
   let contracts =
     List.map
@@ -385,20 +407,15 @@ let init_gen n get ?rng_state ?commitments ?(initial_balances = [])
     ?tx_rollup_origination_size
     ?sc_rollup_enable
     accounts
-  >|=? fun blk -> (blk, get contracts)
+  >|=? fun blk -> (blk, tup_get tup contracts)
 
-let init_n n = init_gen n (fun cs -> cs)
+let init_n n = init_gen (TList n)
 
-let init1 =
-  init_gen 1 (function [contract_1] -> contract_1 | _ -> assert false)
+let init1 = init_gen T1
 
-let init2 =
-  init_gen 2 (function
-      | [contract_1; contract_2] -> (contract_1, contract_2)
-      | _ -> assert false)
+let init2 = init_gen T2
 
-let init3 =
-  init_gen 3 (function [c1; c2; c3] -> (c1, c2, c3) | _ -> assert false)
+let init3 = init_gen T3
 
 let init_with_constants constants n =
   let accounts = Account.generate_accounts n in
-- 
GitLab


From a8279f71006b2024b380acfa84ecc1d13fd2ffaa Mon Sep 17 00:00:00 2001
From: Mehdi Bouaziz <mehdi.bouaziz@nomadic-labs.com>
Date: Fri, 8 Apr 2022 19:40:04 +0200
Subject: [PATCH 4/6] Proto/Tests: simplify Context.Contract.pkh

No need for Lwt-tzresult
---
 .../lib_protocol/test/helpers/context.ml      |  6 ++---
 .../lib_protocol/test/helpers/context.mli     |  2 +-
 .../lib_protocol/test/helpers/op.ml           |  4 ++--
 .../test/integration/consensus/test_baking.ml |  6 ++---
 .../consensus/test_deactivation.ml            |  4 ++--
 .../integration/consensus/test_delegation.ml  |  2 +-
 .../consensus/test_participation.ml           |  8 +++----
 .../operations/test_combined_operations.ml    |  4 ++--
 .../operations/test_origination.ml            |  8 +++----
 .../integration/operations/test_transfer.ml   |  6 ++---
 .../integration/operations/test_voting.ml     | 22 +++++++++----------
 11 files changed, 36 insertions(+), 36 deletions(-)

diff --git a/src/proto_alpha/lib_protocol/test/helpers/context.ml b/src/proto_alpha/lib_protocol/test/helpers/context.ml
index 64e5de8f16de..67d3a806692b 100644
--- a/src/proto_alpha/lib_protocol/test/helpers/context.ml
+++ b/src/proto_alpha/lib_protocol/test/helpers/context.ml
@@ -258,9 +258,9 @@ module Contract = struct
   let equal a b = Alpha_context.Contract.compare a b = 0
 
   let pkh c =
-    Alpha_context.Contract.is_implicit c |> function
-    | Some p -> return p
-    | None -> failwith "pkh: only for implicit contracts"
+    match Alpha_context.Contract.is_implicit c with
+    | Some p -> p
+    | None -> Stdlib.failwith "pkh: only for implicit contracts"
 
   let balance ctxt contract =
     Alpha_services.Contract.balance rpc_ctxt ctxt contract
diff --git a/src/proto_alpha/lib_protocol/test/helpers/context.mli b/src/proto_alpha/lib_protocol/test/helpers/context.mli
index 2709a92c4316..c1ec692cebfe 100644
--- a/src/proto_alpha/lib_protocol/test/helpers/context.mli
+++ b/src/proto_alpha/lib_protocol/test/helpers/context.mli
@@ -117,7 +117,7 @@ module Contract : sig
 
   val equal : Contract.t -> Contract.t -> bool
 
-  val pkh : Contract.t -> public_key_hash tzresult Lwt.t
+  val pkh : Contract.t -> public_key_hash
 
   (** Returns the balance of a contract, by default the main balance.
       If the contract is implicit the frozen balances are available too:
diff --git a/src/proto_alpha/lib_protocol/test/helpers/op.ml b/src/proto_alpha/lib_protocol/test/helpers/op.ml
index 4e3368c7d3ce..efd574bc1567 100644
--- a/src/proto_alpha/lib_protocol/test/helpers/op.ml
+++ b/src/proto_alpha/lib_protocol/test/helpers/op.ml
@@ -453,7 +453,7 @@ let seed_nonce_revelation ctxt level nonce =
   }
 
 let proposals ctxt (pkh : Contract.t) proposals =
-  Context.Contract.pkh pkh >>=? fun source ->
+  let source = Context.Contract.pkh pkh in
   Context.Vote.get_current_period ctxt
   >>=? fun {voting_period = {index; _}; _} ->
   let op = Proposals {source; period = index; proposals} in
@@ -461,7 +461,7 @@ let proposals ctxt (pkh : Contract.t) proposals =
   sign account.sk ctxt (Contents_list (Single op))
 
 let ballot ctxt (pkh : Contract.t) proposal ballot =
-  Context.Contract.pkh pkh >>=? fun source ->
+  let source = Context.Contract.pkh pkh in
   Context.Vote.get_current_period ctxt
   >>=? fun {voting_period = {index; _}; _} ->
   let op = Ballot {source; period = index; proposal; ballot} in
diff --git a/src/proto_alpha/lib_protocol/test/integration/consensus/test_baking.ml b/src/proto_alpha/lib_protocol/test/integration/consensus/test_baking.ml
index cc083464c23c..63f7b3b2de7a 100644
--- a/src/proto_alpha/lib_protocol/test/integration/consensus/test_baking.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/consensus/test_baking.ml
@@ -154,7 +154,7 @@ let test_voting_power_cache () =
 let test_basic_baking_reward () =
   Context.init1 ~consensus_threshold:0 () >>=? fun (genesis, baker) ->
   Block.bake genesis >>=? fun b ->
-  Context.Contract.pkh baker >>=? fun baker_pkh ->
+  let baker_pkh = Context.Contract.pkh baker in
   Context.Contract.balance (B b) baker >>=? fun bal ->
   Context.Delegate.current_frozen_deposits (B b) baker_pkh
   >>=? fun frozen_deposit ->
@@ -170,7 +170,7 @@ let get_contract_for_pkh contracts pkh =
   let rec find_contract = function
     | [] -> assert false
     | c :: t ->
-        Context.Contract.pkh c >>=? fun c_pkh ->
+        let c_pkh = Context.Contract.pkh c in
         if Signature.Public_key_hash.equal c_pkh pkh then return c
         else find_contract t
   in
@@ -313,7 +313,7 @@ let test_enough_active_stake_to_bake ~has_active_stake () =
   let initial_bal1 = if has_active_stake then tpr else Int64.sub tpr 1L in
   Context.init2 ~initial_balances:[initial_bal1; tpr] ~consensus_threshold:0 ()
   >>=? fun (b0, (account1, _account2)) ->
-  Context.Contract.pkh account1 >>=? fun pkh1 ->
+  let pkh1 = Context.Contract.pkh account1 in
   Context.get_constants (B b0)
   >>=? fun Constants.{parametric = {baking_reward_fixed_portion; _}; _} ->
   Block.bake ~policy:(By_account pkh1) b0 >>= fun b1 ->
diff --git a/src/proto_alpha/lib_protocol/test/integration/consensus/test_deactivation.ml b/src/proto_alpha/lib_protocol/test/integration/consensus/test_deactivation.ml
index 2c9daffd2ef7..84544c955cbc 100644
--- a/src/proto_alpha/lib_protocol/test/integration/consensus/test_deactivation.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/consensus/test_deactivation.ml
@@ -87,7 +87,7 @@ let check_no_stake ~loc (b : Block.t) (account : Account.t) =
 let test_simple_staking_rights () =
   Context.init2 () >>=? fun (b, (a1, _a2)) ->
   Context.Contract.balance (B b) a1 >>=? fun balance ->
-  Context.Contract.pkh a1 >>=? fun delegate1 ->
+  let delegate1 = Context.Contract.pkh a1 in
   Context.Delegate.current_frozen_deposits (B b) delegate1
   >>=? fun frozen_deposits ->
   let expected_initial_balance =
@@ -112,7 +112,7 @@ let test_simple_staking_rights_after_baking () =
   Context.Contract.manager (B b) a2 >>=? fun m2 ->
   Block.bake_n ~policy:(By_account m2.pkh) 5 b >>=? fun b ->
   Context.Contract.balance (B b) a1 >>=? fun balance ->
-  Context.Contract.pkh a1 >>=? fun delegate1 ->
+  let delegate1 = Context.Contract.pkh a1 in
   Context.Delegate.current_frozen_deposits (B b) delegate1
   >>=? fun frozen_deposits ->
   balance +? frozen_deposits >>?= fun full_balance ->
diff --git a/src/proto_alpha/lib_protocol/test/integration/consensus/test_delegation.ml b/src/proto_alpha/lib_protocol/test/integration/consensus/test_delegation.ml
index 8696d98612e3..2b46c3e97674 100644
--- a/src/proto_alpha/lib_protocol/test/integration/consensus/test_delegation.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/consensus/test_delegation.ml
@@ -79,7 +79,7 @@ let bootstrap_manager_is_bootstrap_delegate () =
 (** Bootstrap contracts cannot change their delegate. *)
 let bootstrap_delegate_cannot_change ~fee () =
   Context.init2 () >>=? fun (b, (bootstrap0, bootstrap1)) ->
-  Context.Contract.pkh bootstrap0 >>=? fun pkh1 ->
+  let pkh1 = Context.Contract.pkh bootstrap0 in
   Incremental.begin_construction b ~policy:(Block.Excluding [pkh1])
   >>=? fun i ->
   Context.Contract.manager (I i) bootstrap1 >>=? fun manager1 ->
diff --git a/src/proto_alpha/lib_protocol/test/integration/consensus/test_participation.ml b/src/proto_alpha/lib_protocol/test/integration/consensus/test_participation.ml
index 0067b1b1902f..dd930553708e 100644
--- a/src/proto_alpha/lib_protocol/test/integration/consensus/test_participation.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/consensus/test_participation.ml
@@ -81,8 +81,8 @@ let test_participation ~sufficient_participation () =
   let (account1, account2) =
     match accounts with a1 :: a2 :: _ -> (a1, a2) | _ -> assert false
   in
-  Context.Contract.pkh account1 >>=? fun del1 ->
-  Context.Contract.pkh account2 >>=? fun del2 ->
+  let del1 = Context.Contract.pkh account1 in
+  let del2 = Context.Contract.pkh account2 in
   Block.bake ~policy:(By_account del1) b0 >>=? fun b1 ->
   (* To separate concerns, only [del1] bakes: this way, we don't need to
      consider baking rewards for [del2]. Delegate [del2] endorses only
@@ -126,8 +126,8 @@ let test_participation ~sufficient_participation () =
 let test_participation_rpc () =
   let n_accounts = 2 in
   Context.init2 ~consensus_threshold:1 () >>=? fun (b0, (account1, account2)) ->
-  Context.Contract.pkh account1 >>=? fun del1 ->
-  Context.Contract.pkh account2 >>=? fun del2 ->
+  let del1 = Context.Contract.pkh account1 in
+  let del2 = Context.Contract.pkh account2 in
   Context.get_constants (B b0) >>=? fun csts ->
   let blocks_per_cycle = Int32.to_int csts.parametric.blocks_per_cycle in
   let Constants.{numerator; denominator} =
diff --git a/src/proto_alpha/lib_protocol/test/integration/operations/test_combined_operations.ml b/src/proto_alpha/lib_protocol/test/integration/operations/test_combined_operations.ml
index faff59040f8f..ac158b005df2 100644
--- a/src/proto_alpha/lib_protocol/test/integration/operations/test_combined_operations.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/operations/test_combined_operations.ml
@@ -58,7 +58,7 @@ let test_multiple_transfers () =
     (1 -- 10)
   >>=? fun ops ->
   Op.combine_operations ~source:c1 (B blk) ops >>=? fun operation ->
-  Context.Contract.pkh c3 >>=? fun baker_pkh ->
+  let baker_pkh = Context.Contract.pkh c3 in
   Incremental.begin_construction ~policy:(By_account baker_pkh) blk
   >>=? fun inc ->
   Context.Contract.balance (I inc) c1 >>=? fun c1_old_balance ->
@@ -85,7 +85,7 @@ let test_multiple_origination_and_delegation () =
   let n = 10 in
   Context.get_constants (B blk)
   >>=? fun {parametric = {origination_size; cost_per_byte; _}; _} ->
-  Context.Contract.pkh c2 >>=? fun delegate_pkh ->
+  let delegate_pkh = Context.Contract.pkh c2 in
   (* Deploy n smart contracts with dummy scripts from c1 *)
   List.map_es
     (fun i ->
diff --git a/src/proto_alpha/lib_protocol/test/integration/operations/test_origination.ml b/src/proto_alpha/lib_protocol/test/integration/operations/test_origination.ml
index 17059e11c40f..2385c1aff1bf 100644
--- a/src/proto_alpha/lib_protocol/test/integration/operations/test_origination.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/operations/test_origination.ml
@@ -66,8 +66,8 @@ let total_fees_for_origination ?(fee = Tez.zero) ?(credit = Tez.zero) b =
      the bake is done by another delegated. *)
 let test_origination_balances ~loc:_ ?(fee = Tez.zero) ?(credit = Tez.zero) () =
   Context.init2 () >>=? fun (b, (source, contract_for_bake)) ->
-  Context.Contract.pkh source >>=? fun pkh_for_orig ->
-  Context.Contract.pkh contract_for_bake >>=? fun pkh_for_bake ->
+  let pkh_for_orig = Context.Contract.pkh source in
+  let pkh_for_bake = Context.Contract.pkh contract_for_bake in
   Op.contract_origination (B b) source ~fee ~credit ~script:Op.dummy_script
   >>=? fun (operation, new_contract) ->
   total_fees_for_origination ~fee ~credit b >>=? fun total_fee ->
@@ -95,8 +95,8 @@ let test_origination_balances ~loc:_ ?(fee = Tez.zero) ?(credit = Tez.zero) () =
     set to true meaning that this contract is able to delegate. *)
 let register_origination ?(fee = Tez.zero) ?(credit = Tez.zero) () =
   Context.init2 () >>=? fun (b, (source, contract_for_bake)) ->
-  Context.Contract.pkh source >>=? fun source_pkh ->
-  Context.Contract.pkh contract_for_bake >>=? fun pkh_for_bake ->
+  let source_pkh = Context.Contract.pkh source in
+  let pkh_for_bake = Context.Contract.pkh contract_for_bake in
   Op.contract_origination (B b) source ~fee ~credit ~script:Op.dummy_script
   >>=? fun (operation, originated) ->
   Block.bake ~operation ~policy:(By_account pkh_for_bake) b >>=? fun b ->
diff --git a/src/proto_alpha/lib_protocol/test/integration/operations/test_transfer.ml b/src/proto_alpha/lib_protocol/test/integration/operations/test_transfer.ml
index b658448b9b09..c4f27750fb37 100644
--- a/src/proto_alpha/lib_protocol/test/integration/operations/test_transfer.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/operations/test_transfer.ml
@@ -140,7 +140,7 @@ let test_transfer_to_originate_with_fee () =
 (** Transfer from balance. *)
 let test_transfer_amount_of_contract_balance () =
   Context.init2 () >>=? fun (b, (contract_1, contract_2)) ->
-  Context.Contract.pkh contract_1 >>=? fun pkh1 ->
+  let pkh1 = Context.Contract.pkh contract_1 in
   (* given that contract_1 no longer has a sufficient balance to bake,
      make sure it cannot be chosen as baker *)
   Incremental.begin_construction b ~policy:(Block.Excluding [pkh1])
@@ -169,7 +169,7 @@ let test_missing_transaction () =
   Context.init2 () >>=? fun (b, (contract_1, contract_2)) ->
   (* given that contract_1 no longer has a sufficient balance to bake,
      make sure it cannot be chosen as baker *)
-  Context.Contract.pkh contract_1 >>=? fun pkh1 ->
+  let pkh1 = Context.Contract.pkh contract_1 in
   Incremental.begin_construction b ~policy:(Block.Excluding [pkh1])
   >>=? fun b ->
   two_over_n_of_balance b contract_1 6L >>=? fun amount ->
@@ -521,7 +521,7 @@ let test_random_transfer () =
   let contracts = Array.of_list contracts in
   let source = random_contract contracts in
   let dest = random_contract contracts in
-  Context.Contract.pkh source >>=? fun source_pkh ->
+  let source_pkh = Context.Contract.pkh source in
   (* given that source may not have a sufficient balance for the transfer + to bake,
      make sure it cannot be chosen as baker *)
   Incremental.begin_construction b ~policy:(Block.Excluding [source_pkh])
diff --git a/src/proto_alpha/lib_protocol/test/integration/operations/test_voting.ml b/src/proto_alpha/lib_protocol/test/integration/operations/test_voting.ml
index 2e68b6853558..255af2a744bf 100644
--- a/src/proto_alpha/lib_protocol/test/integration/operations/test_voting.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/operations/test_voting.ml
@@ -212,7 +212,7 @@ let get_power b delegates loc =
   Context.Vote.get_listings (B b) >>=? fun l ->
   List.map_es
     (fun delegate ->
-      Context.Contract.pkh delegate >>=? fun pkh ->
+      let pkh = Context.Contract.pkh delegate in
       match List.find_opt (fun (del, _) -> del = pkh) l with
       | None -> failwith "%s - Missing delegate" loc
       | Some (_, power) -> return power)
@@ -358,7 +358,7 @@ let test_successful_vote num_delegates () =
    | l ->
        List.iter_es
          (fun delegate ->
-           Context.Contract.pkh delegate >>=? fun pkh ->
+           let pkh = Context.Contract.pkh delegate in
            match List.find_opt (fun (del, _) -> del = pkh) l with
            | None -> failwith "%s - Missing delegate" __LOC__
            | Some (_, Vote.Yay) -> return_unit
@@ -413,7 +413,7 @@ let test_successful_vote num_delegates () =
    | l ->
        List.iter_es
          (fun delegate ->
-           Context.Contract.pkh delegate >>=? fun pkh ->
+           let pkh = Context.Contract.pkh delegate in
            match List.find_opt (fun (del, _) -> del = pkh) l with
            | None -> failwith "%s - Missing delegate" __LOC__
            | Some (_, Vote.Yay) -> return_unit
@@ -621,7 +621,7 @@ let test_multiple_identical_proposals_count_as_one () =
   (* compute the weight of proposals *)
   Context.Vote.get_proposals (B b) >>=? fun ps ->
   (* compute the voting power of proposer *)
-  Context.Contract.pkh proposer >>=? fun pkh ->
+  let pkh = Context.Contract.pkh proposer in
   Context.Vote.get_listings (B b) >>=? fun l ->
   (match List.find_opt (fun (del, _) -> del = pkh) l with
   | None -> failwith "%s - Missing delegate" __LOC__
@@ -655,8 +655,9 @@ let test_supermajority_in_proposal there_is_a_winner () =
   let del1 = WithExceptions.Option.get ~loc:__LOC__ @@ List.nth delegates 0 in
   let del2 = WithExceptions.Option.get ~loc:__LOC__ @@ List.nth delegates 1 in
   let del3 = WithExceptions.Option.get ~loc:__LOC__ @@ List.nth delegates 2 in
-  List.map_es (fun del -> Context.Contract.pkh del) [del1; del2; del3]
-  >>=? fun pkhs ->
+  let pkhs =
+    List.map (fun del -> Context.Contract.pkh del) [del1; del2; del3]
+  in
   let policy = Block.Excluding pkhs in
   Op.transaction
     (B b)
@@ -707,8 +708,7 @@ let test_quorum_in_proposal has_quorum () =
   >>=? fun {parametric = {min_proposal_quorum; _}; _} ->
   let del1 = WithExceptions.Option.get ~loc:__LOC__ @@ List.nth delegates 0 in
   let del2 = WithExceptions.Option.get ~loc:__LOC__ @@ List.nth delegates 1 in
-  List.map_es (fun del -> Context.Contract.pkh del) [del1; del2]
-  >>=? fun pkhs ->
+  let pkhs = List.map (fun del -> Context.Contract.pkh del) [del1; del2] in
   let policy = Block.Excluding pkhs in
   let quorum =
     if has_quorum then Int64.of_int32 min_proposal_quorum
@@ -895,9 +895,9 @@ let test_voting_power_updated_each_voting_period () =
   let con2 = WithExceptions.Option.get ~loc:__LOC__ @@ List.nth contracts 1 in
   let con3 = WithExceptions.Option.get ~loc:__LOC__ @@ List.nth contracts 2 in
   (* Get the key hashes of the bakers *)
-  Context.Contract.pkh con1 >>=? fun baker1 ->
-  Context.Contract.pkh con2 >>=? fun baker2 ->
-  Context.Contract.pkh con3 >>=? fun baker3 ->
+  let baker1 = Context.Contract.pkh con1 in
+  let baker2 = Context.Contract.pkh con2 in
+  let baker3 = Context.Contract.pkh con3 in
   (* Retrieve balance of con1 *)
   let open Test_tez in
   Context.Contract.balance (B genesis) con1 >>=? fun balance1 ->
-- 
GitLab


From 1f1f67a7f0cb8d221d9c9ad85ac66e8cea0eaf0e Mon Sep 17 00:00:00 2001
From: Mehdi Bouaziz <mehdi.bouaziz@nomadic-labs.com>
Date: Mon, 11 Apr 2022 08:57:15 +0200
Subject: [PATCH 5/6] Proto/Tests: simplify calls to
 Context.init_with_constants

init_with_constants1, init_with_constants2 are used whenever possible.
init_with_constants is renamed into init_with_constants_n to discourage its usage.
---
 .../lib_protocol/test/helpers/context.ml      | 12 ++++-
 .../lib_protocol/test/helpers/context.mli     | 10 +++-
 .../consensus/test_double_endorsement.ml      | 23 ++------
 .../consensus/test_frozen_deposits.ml         | 54 ++++++-------------
 .../test/integration/consensus/test_seed.ml   | 11 +---
 .../michelson/test_block_time_instructions.ml |  2 +-
 .../integration/operations/test_sc_rollup.ml  |  2 +-
 .../integration/operations/test_tx_rollup.ml  | 23 +++-----
 8 files changed, 47 insertions(+), 90 deletions(-)

diff --git a/src/proto_alpha/lib_protocol/test/helpers/context.ml b/src/proto_alpha/lib_protocol/test/helpers/context.ml
index 67d3a806692b..b881b3ed7a07 100644
--- a/src/proto_alpha/lib_protocol/test/helpers/context.ml
+++ b/src/proto_alpha/lib_protocol/test/helpers/context.ml
@@ -417,7 +417,8 @@ let init2 = init_gen T2
 
 let init3 = init_gen T3
 
-let init_with_constants constants n =
+let init_with_constants_gen tup constants =
+  let n = tup_n tup in
   let accounts = Account.generate_accounts n in
   let contracts =
     List.map
@@ -435,7 +436,14 @@ let init_with_constants constants n =
   let parameters =
     Default_parameters.parameters_of_constants ~bootstrap_accounts constants
   in
-  Block.genesis_with_parameters parameters >|=? fun blk -> (blk, contracts)
+  Block.genesis_with_parameters parameters >|=? fun blk ->
+  (blk, tup_get tup contracts)
+
+let init_with_constants_n consts n = init_with_constants_gen (TList n) consts
+
+let init_with_constants1 = init_with_constants_gen T1
+
+let init_with_constants2 = init_with_constants_gen T2
 
 let default_raw_context () =
   let initial_accounts =
diff --git a/src/proto_alpha/lib_protocol/test/helpers/context.mli b/src/proto_alpha/lib_protocol/test/helpers/context.mli
index c1ec692cebfe..7c6d2bbd2207 100644
--- a/src/proto_alpha/lib_protocol/test/helpers/context.mli
+++ b/src/proto_alpha/lib_protocol/test/helpers/context.mli
@@ -245,11 +245,19 @@ val init3 :
   * Alpha_context.Contract.t)
   init
 
-val init_with_constants :
+val init_with_constants_n :
   Constants.parametric ->
   int ->
   (Block.t * Alpha_context.Contract.t list) tzresult Lwt.t
 
+val init_with_constants1 :
+  Constants.parametric -> (Block.t * Alpha_context.Contract.t) tzresult Lwt.t
+
+val init_with_constants2 :
+  Constants.parametric ->
+  (Block.t * (Alpha_context.Contract.t * Alpha_context.Contract.t)) tzresult
+  Lwt.t
+
 (** [default_raw_context] returns a [Raw_context.t] for use in tests
     below [Alpha_context] *)
 val default_raw_context : unit -> Raw_context.t tzresult Lwt.t
diff --git a/src/proto_alpha/lib_protocol/test/integration/consensus/test_double_endorsement.ml b/src/proto_alpha/lib_protocol/test/integration/consensus/test_double_endorsement.ml
index 56a50dea5829..9c65e938bc6c 100644
--- a/src/proto_alpha/lib_protocol/test/integration/consensus/test_double_endorsement.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/consensus/test_double_endorsement.ml
@@ -49,22 +49,6 @@ let block_fork b =
 (*                        Tests                                 *)
 (****************************************************************)
 
-let get_first_2_accounts_contracts contracts =
-  let ((contract1, account1), (contract2, account2)) =
-    match contracts with
-    | [a1; a2] ->
-        ( ( a1,
-            Contract.is_implicit a1 |> function
-            | None -> assert false
-            | Some pkh -> pkh ),
-          ( a2,
-            Contract.is_implicit a2 |> function
-            | None -> assert false
-            | Some pkh -> pkh ) )
-    | _ -> assert false
-  in
-  ((contract1, account1), (contract2, account2))
-
 let order_endorsements ~correct_order op1 op2 =
   let oph1 = Operation.hash op1 in
   let oph2 = Operation.hash op2 in
@@ -362,10 +346,9 @@ let test_freeze_more_with_low_balance =
           {numerator = 1; denominator = 2};
       }
     in
-    Context.init_with_constants constants 2 >>=? fun (genesis, contracts) ->
-    let ((_contract1, account1), (_contract2, account2)) =
-      get_first_2_accounts_contracts contracts
-    in
+    Context.init_with_constants2 constants >>=? fun (genesis, (c1, c2)) ->
+    let account1 = Context.Contract.pkh c1 in
+    let account2 = Context.Contract.pkh c2 in
     (* we empty the available balance of [account1]. *)
     Context.Delegate.info (B genesis) account1 >>=? fun info1 ->
     Op.transaction
diff --git a/src/proto_alpha/lib_protocol/test/integration/consensus/test_frozen_deposits.ml b/src/proto_alpha/lib_protocol/test/integration/consensus/test_frozen_deposits.ml
index 1b15f0387965..ceab5304647e 100644
--- a/src/proto_alpha/lib_protocol/test/integration/consensus/test_frozen_deposits.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/consensus/test_frozen_deposits.ml
@@ -46,21 +46,8 @@ let constants =
     origination_size = 0;
   }
 
-let get_first_2_accounts_contracts contracts =
-  let ((contract1, account1), (contract2, account2)) =
-    match contracts with
-    | [a1; a2] ->
-        ( ( a1,
-            Contract.is_implicit a1 |> function
-            | None -> assert false
-            | Some pkh -> pkh ),
-          ( a2,
-            Contract.is_implicit a2 |> function
-            | None -> assert false
-            | Some pkh -> pkh ) )
-    | _ -> assert false
-  in
-  ((contract1, account1), (contract2, account2))
+let get_first_2_accounts_contracts (a1, a2) =
+  ((a1, Context.Contract.pkh a1), (a2, Context.Contract.pkh a2))
 
 (* Terminology:
 
@@ -80,7 +67,7 @@ let get_first_2_accounts_contracts contracts =
 - full balance = spendable balance + frozen deposits; obtained with Delegate.full_balance
 *)
 let test_invariants () =
-  Context.init_with_constants constants 2 >>=? fun (genesis, contracts) ->
+  Context.init_with_constants2 constants >>=? fun (genesis, contracts) ->
   let ((contract1, account1), (contract2, _account2)) =
     get_first_2_accounts_contracts contracts
   in
@@ -141,7 +128,7 @@ let test_invariants () =
   Assert.equal_tez ~loc:__LOC__ new_frozen_deposits expected_new_frozen_deposits
 
 let test_set_limit balance_percentage () =
-  Context.init_with_constants constants 2 >>=? fun (genesis, contracts) ->
+  Context.init_with_constants2 constants >>=? fun (genesis, contracts) ->
   let ((contract1, account1), (_contract2, account2)) =
     get_first_2_accounts_contracts contracts
   in
@@ -199,7 +186,7 @@ let test_set_limit balance_percentage () =
   Assert.equal_tez ~loc:__LOC__ frozen_deposits limit
 
 let test_set_too_high_limit () =
-  Context.init_with_constants constants 2 >>=? fun (genesis, contracts) ->
+  Context.init_with_constants2 constants >>=? fun (genesis, contracts) ->
   let ((contract1, _account1), _) = get_first_2_accounts_contracts contracts in
   let max_limit =
     Tez.of_mutez_exn
@@ -228,7 +215,7 @@ let test_set_too_high_limit () =
   Incremental.finalize_block b >>=? fun _ -> return_unit
 
 let test_unset_limit () =
-  Context.init_with_constants constants 2 >>=? fun (genesis, contracts) ->
+  Context.init_with_constants2 constants >>=? fun (genesis, contracts) ->
   let ((contract1, account1), (_contract2, account2)) =
     get_first_2_accounts_contracts contracts
   in
@@ -275,7 +262,7 @@ let test_unset_limit () =
   >>=? fun () -> return_unit
 
 let test_cannot_bake_with_zero_deposits () =
-  Context.init_with_constants constants 2 >>=? fun (genesis, contracts) ->
+  Context.init_with_constants2 constants >>=? fun (genesis, contracts) ->
   let ((contract1, account1), (_contract2, account2)) =
     get_first_2_accounts_contracts contracts
   in
@@ -308,7 +295,7 @@ let test_cannot_bake_with_zero_deposits () =
   Assert.error ~loc:__LOC__ b1 (fun _ -> true)
 
 let test_deposits_after_stake_removal () =
-  Context.init_with_constants constants 2 >>=? fun (genesis, contracts) ->
+  Context.init_with_constants2 constants >>=? fun (genesis, contracts) ->
   let ((contract1, account1), (contract2, account2)) =
     get_first_2_accounts_contracts contracts
   in
@@ -376,7 +363,7 @@ let test_deposits_after_stake_removal () =
   Assert.equal_tez ~loc:__LOC__ frozen_deposits_2 expected_new_frozen_deposits_2
 
 let test_unfreeze_deposits_after_deactivation () =
-  Context.init_with_constants constants 2 >>=? fun (genesis, contracts) ->
+  Context.init_with_constants2 constants >>=? fun (genesis, contracts) ->
   let ((contract1, account1), (_contract2, account2)) =
     get_first_2_accounts_contracts contracts
   in
@@ -422,7 +409,7 @@ let test_unfreeze_deposits_after_deactivation () =
   loop genesis cycles_to_bake >>=? fun _b -> return_unit
 
 let test_frozen_deposits_with_delegation () =
-  Context.init_with_constants constants 2 >>=? fun (genesis, contracts) ->
+  Context.init_with_constants2 constants >>=? fun (genesis, contracts) ->
   let ((_contract1, account1), (contract2, account2)) =
     get_first_2_accounts_contracts contracts
   in
@@ -482,7 +469,7 @@ let test_frozen_deposits_with_delegation () =
   loop b cycles_to_bake >>=? fun _b -> return_unit
 
 let test_frozen_deposits_with_overdelegation () =
-  Context.init_with_constants constants 2 >>=? fun (genesis, contracts) ->
+  Context.init_with_constants2 constants >>=? fun (genesis, contracts) ->
   let ((contract1, account1), (contract2, account2)) =
     get_first_2_accounts_contracts contracts
   in
@@ -561,7 +548,7 @@ let test_frozen_deposits_with_overdelegation () =
 
 let test_set_limit_with_overdelegation () =
   let constants = {constants with frozen_deposits_percentage = 10} in
-  Context.init_with_constants constants 2 >>=? fun (genesis, contracts) ->
+  Context.init_with_constants2 constants >>=? fun (genesis, contracts) ->
   let ((contract1, account1), (contract2, account2)) =
     get_first_2_accounts_contracts contracts
   in
@@ -629,20 +616,9 @@ let test_set_limit_with_overdelegation () =
 (** This test fails when [to_cycle] in [Delegate.freeze_deposits] is smaller than
    [new_cycle + preserved_cycles]. *)
 let test_error_is_thrown_when_smaller_upper_bound_for_frozen_window () =
-  Context.init_with_constants constants 2 >>=? fun (genesis, contracts) ->
-  let ((contract1, account1), (contract2, _account2)) =
-    match contracts with
-    | [a1; a2] ->
-        ( ( a1,
-            Contract.is_implicit a1 |> function
-            | None -> assert false
-            | Some pkh -> pkh ),
-          ( a2,
-            Contract.is_implicit a2 |> function
-            | None -> assert false
-            | Some pkh -> pkh ) )
-    | _ -> assert false
-  in
+  Context.init_with_constants2 constants >>=? fun (genesis, contracts) ->
+  let (contract1, contract2) = contracts in
+  let account1 = Context.Contract.pkh contract1 in
   (* [account2] delegates (through [new_account]) to [account1] its spendable
      balance. The point is to make [account1] have a lot of staking balance so
      that, after [preserved_cycles] when the active stake reflects this increase
diff --git a/src/proto_alpha/lib_protocol/test/integration/consensus/test_seed.ml b/src/proto_alpha/lib_protocol/test/integration/consensus/test_seed.ml
index 6fcafa49efd3..85cf20c0e645 100644
--- a/src/proto_alpha/lib_protocol/test/integration/consensus/test_seed.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/consensus/test_seed.ml
@@ -188,15 +188,8 @@ let test_unrevealed () =
       minimal_participation_ratio = Constants.{numerator = 0; denominator = 1};
     }
   in
-  Context.init_with_constants constants 2 >>=? fun (b, accounts) ->
-  let (account1, account2) =
-    match accounts with a1 :: a2 :: _ -> (a1, a2) | _ -> assert false
-  in
-  let (_delegate1, delegate2) =
-    match (Contract.is_implicit account1, Contract.is_implicit account2) with
-    | (Some d, Some d') -> (d, d')
-    | _ -> assert false
-  in
+  Context.init_with_constants2 constants >>=? fun (b, (_account1, account2)) ->
+  let delegate2 = Context.Contract.pkh account2 in
   (* Delegate 2 will add a nonce but never reveals it *)
   Context.get_constants (B b) >>=? fun csts ->
   let blocks_per_commitment =
diff --git a/src/proto_alpha/lib_protocol/test/integration/michelson/test_block_time_instructions.ml b/src/proto_alpha/lib_protocol/test/integration/michelson/test_block_time_instructions.ml
index 09ae3ed90c6d..44a4a6a8887e 100644
--- a/src/proto_alpha/lib_protocol/test/integration/michelson/test_block_time_instructions.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/michelson/test_block_time_instructions.ml
@@ -37,7 +37,7 @@ open Alpha_context
 
 let context_with_constants constants =
   let open Lwt_result_syntax in
-  let* (block, _contracts) = Context.init_with_constants constants 1 in
+  let* (block, _contracts) = Context.init_with_constants1 constants in
   let+ incremental = Incremental.begin_construction block in
   Incremental.alpha_ctxt incremental
 
diff --git a/src/proto_alpha/lib_protocol/test/integration/operations/test_sc_rollup.ml b/src/proto_alpha/lib_protocol/test/integration/operations/test_sc_rollup.ml
index cacd247bda80..9f7c76e9ee52 100644
--- a/src/proto_alpha/lib_protocol/test/integration/operations/test_sc_rollup.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/operations/test_sc_rollup.ml
@@ -44,7 +44,7 @@ let err x = Exn (Sc_rollup_test_error x)
   [sc_rollup_enable] constant is set to true. It returns the created
   context and [n] contracts. *)
 let context_init n =
-  Context.init_with_constants
+  Context.init_with_constants_n
     {
       Context.default_test_constants with
       sc_rollup_enable = true;
diff --git a/src/proto_alpha/lib_protocol/test/integration/operations/test_tx_rollup.ml b/src/proto_alpha/lib_protocol/test/integration/operations/test_tx_rollup.ml
index 635a8b8ee993..3d69805c47b9 100644
--- a/src/proto_alpha/lib_protocol/test/integration/operations/test_tx_rollup.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/operations/test_tx_rollup.ml
@@ -64,13 +64,9 @@ let is_implicit_exn x =
 (** [test_disable_feature_flag] try to originate a tx rollup with the feature
     flag is deactivated and check it fails *)
 let test_disable_feature_flag () =
-  Context.init_with_constants
+  Context.init_with_constants1
     {Context.default_test_constants with tx_rollup_enable = false}
-    1
-  >>=? fun (b, contracts) ->
-  let contract =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.nth contracts 0
-  in
+  >>=? fun (b, contract) ->
   Incremental.begin_construction b >>=? fun i ->
   Op.tx_rollup_origination (I i) contract >>=? fun (op, _tx_rollup) ->
   Incremental.add_operation
@@ -82,17 +78,13 @@ let test_disable_feature_flag () =
 (** [test_sunset] try to originate a tx rollup after the sunset and check
     that it fails *)
 let test_sunset () =
-  Context.init_with_constants
+  Context.init_with_constants1
     {
       Context.default_test_constants with
       tx_rollup_enable = true;
       tx_rollup_sunset_level = 0l;
     }
-    1
-  >>=? fun (b, contracts) ->
-  let contract =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.nth contracts 0
-  in
+  >>=? fun (b, contract) ->
   Incremental.begin_construction b >>=? fun i ->
   Op.tx_rollup_origination (I i) contract >>=? fun (op, _tx_rollup) ->
   Incremental.add_operation
@@ -203,7 +195,7 @@ let context_init ?(tx_rollup_max_inboxes_count = 2100)
     ?(tx_rollup_finality_period = 1) ?(tx_rollup_origination_size = 60_000)
     ?(cost_per_byte = Tez.zero) ?(tx_rollup_hard_size_limit_per_message = 5_000)
     n =
-  Context.init_with_constants
+  Context.init_with_constants_n
     {
       Context.default_test_constants with
       consensus_threshold = 0;
@@ -1936,10 +1928,7 @@ let test_full_inbox () =
       tx_rollup_max_inboxes_count = 15;
     }
   in
-  Context.init_with_constants constants 1 >>=? fun (b, contracts) ->
-  let contract =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.nth contracts 0
-  in
+  Context.init_with_constants1 constants >>=? fun (b, contract) ->
   originate b contract >>=? fun (b, tx_rollup) ->
   let range start top =
     let rec aux n acc = if n < start then acc else aux (n - 1) (n :: acc) in
-- 
GitLab


From 32ec8e7b76c1b1cac4fb5952cfdb94f39e4198aa Mon Sep 17 00:00:00 2001
From: Mehdi Bouaziz <mehdi.bouaziz@nomadic-labs.com>
Date: Mon, 11 Apr 2022 09:15:14 +0200
Subject: [PATCH 6/6] Proto/Tests: further simplifications of calls to
 Context.init_with_constants_n

init_with_constants_n is actually never used generically
---
 .../lib_protocol/test/helpers/context.ml      |  9 +++
 .../lib_protocol/test/helpers/context.mli     | 13 ++++
 .../integration/operations/test_sc_rollup.ml  | 45 +++++--------
 .../integration/operations/test_tx_rollup.ml  | 64 ++++++-------------
 4 files changed, 59 insertions(+), 72 deletions(-)

diff --git a/src/proto_alpha/lib_protocol/test/helpers/context.ml b/src/proto_alpha/lib_protocol/test/helpers/context.ml
index b881b3ed7a07..07c5f3953a5b 100644
--- a/src/proto_alpha/lib_protocol/test/helpers/context.ml
+++ b/src/proto_alpha/lib_protocol/test/helpers/context.ml
@@ -360,6 +360,15 @@ type (_, _) tup =
   | T3 : ('a, 'a * 'a * 'a) tup
   | TList : int -> ('a, 'a list) tup
 
+let tup_hd : type a r. (a, r) tup -> r -> a =
+ fun tup elts ->
+  match (tup, elts) with
+  | (T1, v) -> v
+  | (T2, (v, _)) -> v
+  | (T3, (v, _, _)) -> v
+  | (TList _, v :: _) -> v
+  | (TList _, []) -> assert false
+
 let tup_n : type a r. (a, r) tup -> int = function
   | T1 -> 1
   | T2 -> 2
diff --git a/src/proto_alpha/lib_protocol/test/helpers/context.mli b/src/proto_alpha/lib_protocol/test/helpers/context.mli
index 7c6d2bbd2207..6f4b244732f6 100644
--- a/src/proto_alpha/lib_protocol/test/helpers/context.mli
+++ b/src/proto_alpha/lib_protocol/test/helpers/context.mli
@@ -202,6 +202,14 @@ module Tx_rollup : sig
     Tx_rollup_commitment.Submitted_commitment.t option tzresult Lwt.t
 end
 
+type (_, _) tup =
+  | T1 : ('a, 'a) tup
+  | T2 : ('a, 'a * 'a) tup
+  | T3 : ('a, 'a * 'a * 'a) tup
+  | TList : int -> ('a, 'a list) tup
+
+val tup_hd : ('a, 'elts) tup -> 'elts -> 'a
+
 type 'accounts init :=
   ?rng_state:Random.State.t ->
   ?commitments:Commitment.t list ->
@@ -245,6 +253,11 @@ val init3 :
   * Alpha_context.Contract.t)
   init
 
+val init_with_constants_gen :
+  (Alpha_context.Contract.t, 'contracts) tup ->
+  Constants.parametric ->
+  (Block.t * 'contracts) tzresult Lwt.t
+
 val init_with_constants_n :
   Constants.parametric ->
   int ->
diff --git a/src/proto_alpha/lib_protocol/test/integration/operations/test_sc_rollup.ml b/src/proto_alpha/lib_protocol/test/integration/operations/test_sc_rollup.ml
index 9f7c76e9ee52..d890fa07fdea 100644
--- a/src/proto_alpha/lib_protocol/test/integration/operations/test_sc_rollup.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/operations/test_sc_rollup.ml
@@ -40,18 +40,18 @@ exception Sc_rollup_test_error of string
 
 let err x = Exn (Sc_rollup_test_error x)
 
-(** [context_init n] initializes a context for testing in which the
+(** [context_init tup] initializes a context for testing in which the
   [sc_rollup_enable] constant is set to true. It returns the created
-  context and [n] contracts. *)
-let context_init n =
-  Context.init_with_constants_n
+  context and contracts. *)
+let context_init tup =
+  Context.init_with_constants_gen
+    tup
     {
       Context.default_test_constants with
       sc_rollup_enable = true;
       consensus_threshold = 0;
       sc_rollup_challenge_window_in_blocks = 10;
     }
-    n
 
 (** [test_disable_feature_flag ()] tries to originate a smart contract
    rollup when the feature flag is deactivated and checks that it
@@ -105,11 +105,9 @@ let test_sc_rollups_all_well_defined () =
   all_names_are_valid ()
 
 (** Initializes the context and originates a SCORU. *)
-let init_and_originate n =
-  let* (ctxt, contracts) = context_init n in
-  let contract =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.nth contracts 0
-  in
+let init_and_originate tup =
+  let* (ctxt, contracts) = context_init tup in
+  let contract = Context.tup_hd tup contracts in
   let kind = Sc_rollup.Kind.Example_arith in
   let* (operation, rollup) =
     Op.sc_rollup_origination (B ctxt) contract kind ""
@@ -147,10 +145,8 @@ let dummy_commitment =
 (** [test_publish_and_cement] creates a rollup, publishes a
     commitment and then 20 blocks later cements that commitment *)
 let test_publish_and_cement () =
-  let* (ctxt, contracts, rollup) = init_and_originate 2 in
-  let contract =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.nth contracts 1
-  in
+  let* (ctxt, contracts, rollup) = init_and_originate Context.T2 in
+  let (_, contract) = contracts in
   let* operation =
     Op.sc_rollup_publish (B ctxt) contract rollup dummy_commitment
   in
@@ -169,10 +165,8 @@ let test_publish_and_cement () =
     without waiting for the challenge period to elapse. We check that
     this fails with the correct error. *)
 let test_cement_fails_if_premature () =
-  let* (ctxt, contracts, rollup) = init_and_originate 2 in
-  let contract =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.nth contracts 1
-  in
+  let* (ctxt, contracts, rollup) = init_and_originate Context.T2 in
+  let (_, contract) = contracts in
   let* operation =
     Op.sc_rollup_publish (B ctxt) contract rollup dummy_commitment
   in
@@ -197,10 +191,8 @@ let test_cement_fails_if_premature () =
     publishes two different commitments with the same staker. We check
     that the second publish fails. *)
 let test_publish_fails_on_backtrack () =
-  let* (ctxt, contracts, rollup) = init_and_originate 2 in
-  let contract =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.nth contracts 1
-  in
+  let* (ctxt, contracts, rollup) = init_and_originate Context.T2 in
+  let (_, contract) = contracts in
   let commitment1 = dummy_commitment in
   let commitment2 =
     {dummy_commitment with number_of_ticks = number_of_ticks_exn 3001l}
@@ -227,13 +219,8 @@ let test_publish_fails_on_backtrack () =
     cement one of the commitments; it checks that this fails because the
     commitment is contested. *)
 let test_cement_fails_on_conflict () =
-  let* (ctxt, contracts, rollup) = init_and_originate 3 in
-  let contract1 =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.nth contracts 1
-  in
-  let contract2 =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.nth contracts 2
-  in
+  let* (ctxt, contracts, rollup) = init_and_originate Context.T3 in
+  let (_, contract1, contract2) = contracts in
   let commitment1 = dummy_commitment in
   let commitment2 =
     {dummy_commitment with number_of_ticks = number_of_ticks_exn 3001l}
diff --git a/src/proto_alpha/lib_protocol/test/integration/operations/test_tx_rollup.ml b/src/proto_alpha/lib_protocol/test/integration/operations/test_tx_rollup.ml
index 3d69805c47b9..46ee8d89f26c 100644
--- a/src/proto_alpha/lib_protocol/test/integration/operations/test_tx_rollup.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/operations/test_tx_rollup.ml
@@ -186,16 +186,17 @@ let inbox_burn state size =
     the inbox. *)
 let burn_per_byte state = inbox_burn state 1
 
-(** [context_init n] initializes a context with no consensus rewards
+(** [context_init tup] initializes a context with no consensus rewards
     to not interfere with balances prediction. It returns the created
-    context and [n] contracts. *)
+    context and contracts. *)
 let context_init ?(tx_rollup_max_inboxes_count = 2100)
     ?(tx_rollup_rejection_max_proof_size = 30_000)
     ?(tx_rollup_max_ticket_payload_size = 10_240)
     ?(tx_rollup_finality_period = 1) ?(tx_rollup_origination_size = 60_000)
     ?(cost_per_byte = Tez.zero) ?(tx_rollup_hard_size_limit_per_message = 5_000)
-    n =
-  Context.init_with_constants_n
+    tup =
+  Context.init_with_constants_gen
+    tup
     {
       Context.default_test_constants with
       consensus_threshold = 0;
@@ -214,7 +215,6 @@ let context_init ?(tx_rollup_max_inboxes_count = 2100)
       tx_rollup_max_ticket_payload_size;
       cost_per_byte;
     }
-    n
 
 (** [context_init1] initializes a context with no consensus rewards
     to not interfere with balances prediction. It returns the created
@@ -231,10 +231,7 @@ let context_init1 ?tx_rollup_max_inboxes_count
     ?tx_rollup_origination_size
     ?cost_per_byte
     ?tx_rollup_hard_size_limit_per_message
-    1
-  >|=? function
-  | (b, contract_1 :: _) -> (b, contract_1)
-  | (_, _) -> assert false
+    Context.T1
 
 (** [context_init2] initializes a context with no consensus rewards
     to not interfere with balances prediction. It returns the created
@@ -247,10 +244,7 @@ let context_init2 ?tx_rollup_max_inboxes_count
     ?tx_rollup_max_ticket_payload_size
     ?cost_per_byte
     ?tx_rollup_hard_size_limit_per_message
-    2
-  >|=? function
-  | (b, contract_1 :: contract_2 :: _) -> (b, (contract_1, contract_2))
-  | (_, _) -> assert false
+    Context.T2
 
 (** [originate b contract] originates a tx_rollup from [contract],
     and returns the new block and the tx_rollup address. *)
@@ -1415,10 +1409,7 @@ let test_valid_deposit_invalid_amount () =
 let test_deposit_too_many_tickets () =
   let too_many = Z.succ (Z.of_int64 Int64.max_int) in
   let (_, _, pkh) = gen_l2_account () in
-  context_init 1 >>=? fun (block, accounts) ->
-  let account1 =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.nth accounts 0
-  in
+  context_init1 () >>=? fun (block, account1) ->
   originate block account1 >>=? fun (block, tx_rollup) ->
   Nat_ticket.init_deposit too_many block tx_rollup account1
   >>=? fun (operation, b, deposit_contract) ->
@@ -1455,11 +1446,9 @@ let test_deposit_by_non_internal_operation () =
 
 (** Test that block finalization changes gas rates *)
 let test_finalization () =
-  context_init ~tx_rollup_max_inboxes_count:5_000 2 >>=? fun (b, contracts) ->
-  let filler = WithExceptions.Option.get ~loc:__LOC__ @@ List.nth contracts 0 in
-  let contract =
-    WithExceptions.Option.get ~loc:__LOC__ @@ List.nth contracts 0
-  in
+  context_init2 ~tx_rollup_max_inboxes_count:5_000 () >>=? fun (b, contracts) ->
+  let (contract, _) = contracts in
+  let filler = contract in
   originate b contract >>=? fun (b, tx_rollup) ->
   Context.get_constants (B b)
   >>=? fun {parametric = {tx_rollup_hard_size_limit_per_inbox; _}; _} ->
@@ -2919,10 +2908,7 @@ module Rejection = struct
   (** Test that rejection successfully fails when there's no commitment to
       reject *)
   let test_no_commitment () =
-    context_init 1 >>=? fun (b, contracts) ->
-    let contract =
-      WithExceptions.Option.get ~loc:__LOC__ @@ List.nth contracts 0
-    in
+    context_init1 () >>=? fun (b, contract) ->
     originate b contract >>=? fun (b, tx_rollup) ->
     let message = "bogus" in
     Op.tx_rollup_submit_batch (B b) contract tx_rollup message
@@ -3787,15 +3773,13 @@ let test_state_message_storage_preallocation () =
   return_unit
 
 module Withdraw = struct
-  (** [context_init_withdraw n] initializes a context with [n + 1] accounts, one rollup and a
+  (** [context_init_withdraw tup] initializes a context with [tup] accounts, one rollup and a
       withdrawal recipient contract. *)
   let context_init_withdraw ?tx_rollup_origination_size
-      ?(amount = Z.of_int64 @@ Tx_rollup_l2_qty.to_int64 Nat_ticket.amount) n =
-    context_init ?tx_rollup_origination_size (n + 1)
-    >>=? fun (block, accounts) ->
-    let account1 =
-      WithExceptions.Option.get ~loc:__LOC__ @@ List.nth accounts 0
-    in
+      ?(amount = Z.of_int64 @@ Tx_rollup_l2_qty.to_int64 Nat_ticket.amount) tup
+      =
+    context_init ?tx_rollup_origination_size tup >>=? fun (block, accounts) ->
+    let account1 = Context.tup_hd tup accounts in
     originate block account1 >>=? fun (block, tx_rollup) ->
     Nat_ticket.init_deposit amount block tx_rollup account1
     >>=? fun (operation, block, deposit_contract) ->
@@ -3819,7 +3803,7 @@ module Withdraw = struct
   (** [context_init1_withdraw] initializes a context with one account, one rollup and a
       withdrawal recipient contract. *)
   let context_init1_withdraw () =
-    context_init_withdraw 0
+    context_init_withdraw Context.T1
     >>=? fun ( account1,
                _accounts,
                tx_rollup,
@@ -3831,16 +3815,13 @@ module Withdraw = struct
   (** [context_init2_withdraw] initializes a context with two accounts, one rollup and a
       withdrawal recipient contract. *)
   let context_init2_withdraw () =
-    context_init_withdraw 1
+    context_init_withdraw Context.T2
     >>=? fun ( account1,
-               accounts,
+               (_, account2),
                tx_rollup,
                deposit_contract,
                withdraw_contract,
                b ) ->
-    let account2 =
-      WithExceptions.Option.get ~loc:__LOC__ @@ List.nth accounts 1
-    in
     return
       (account1, account2, tx_rollup, deposit_contract, withdraw_contract, b)
 
@@ -4957,10 +4938,7 @@ module Withdraw = struct
        we overflow. *)
     let max = Int64.(sub max_int 1L) in
     let (_, _, pkh) = gen_l2_account () in
-    context_init 1 >>=? fun (b, accounts) ->
-    let account1 =
-      WithExceptions.Option.get ~loc:__LOC__ @@ List.nth accounts 0
-    in
+    context_init1 () >>=? fun (b, account1) ->
     originate b account1 >>=? fun (b, tx_rollup) ->
     let pkh_str = Tx_rollup_l2_address.to_b58check pkh in
     Nat_ticket.init_deposit_contract (Z.of_int64 max) b account1
-- 
GitLab