[go: up one dir, main page]

quote 0.3.13

Quasi-quoting macro quote!(...)
Documentation
use std::{f32, f64};
use std::borrow::Cow;

#[macro_use]
extern crate quote;

struct X;

impl quote::ToTokens for X {
    fn to_tokens(&self, tokens: &mut quote::Tokens) {
        tokens.append("X");
    }
}

#[test]
fn test_quote_impl() {
    let tokens = quote!(
        impl<'a, T: ToTokens> ToTokens for &'a T {
            fn to_tokens(&self, tokens: &mut Tokens) {
                (**self).to_tokens(tokens)
            }
        }
    );

    let expected = concat!(
        "impl < 'a , T : ToTokens > ToTokens for & 'a T { ",
            "fn to_tokens ( & self , tokens : & mut Tokens ) { ",
                "( * * self ) . to_tokens ( tokens ) ",
            "} ",
        "}"
    );

    assert_eq!(expected, tokens.as_str());
}

#[test]
fn test_substitution() {
    let x = X;
    let tokens = quote!(#x <#x> (#x) [#x] {#x});

    let expected = "X < X > ( X ) [ X ] { X }";

    assert_eq!(expected, tokens.as_str());
}

#[test]
fn test_iter() {
    let primes = &[X, X, X, X];

    assert_eq!("X X X X", quote!(#(#primes)*).as_str());

    assert_eq!("X , X , X , X ,", quote!(#(#primes,)*).as_str());

    assert_eq!("X , X , X , X", quote!(#(#primes),*).as_str());
}

#[test]
fn test_advanced() {
    let generics = quote!( <'a, T> );

    let where_clause = quote!( where T: Serialize );

    let field_ty = quote!( String );

    let item_ty = quote!( Cow<'a, str> );

    let path = quote!( SomeTrait::serialize_with );

    let value = quote!( self.x );

    let tokens = quote! {
        struct SerializeWith #generics #where_clause {
            value: &'a #field_ty,
            phantom: ::std::marker::PhantomData<#item_ty>,
        }

        impl #generics ::serde::Serialize for SerializeWith #generics #where_clause {
            fn serialize<S>(&self, s: &mut S) -> Result<(), S::Error>
                where S: ::serde::Serializer
            {
                #path(self.value, s)
            }
        }

        SerializeWith {
            value: #value,
            phantom: ::std::marker::PhantomData::<#item_ty>,
        }
    };

    let expected = concat!(
        "struct SerializeWith < 'a , T > where T : Serialize { ",
            "value : & 'a String , ",
            "phantom : :: std :: marker :: PhantomData < Cow < 'a , str > > , ",
        "} ",
        "impl < 'a , T > :: serde :: Serialize for SerializeWith < 'a , T > where T : Serialize { ",
            "fn serialize < S > ( & self , s : & mut S ) -> Result < ( ) , S :: Error > ",
                "where S : :: serde :: Serializer ",
            "{ ",
                "SomeTrait :: serialize_with ( self . value , s ) ",
            "} ",
        "} ",
        "SerializeWith { ",
            "value : self . x , ",
            "phantom : :: std :: marker :: PhantomData :: < Cow < 'a , str > > , ",
        "}"
    );

    assert_eq!(expected, tokens.as_str());
}

#[test]
fn test_unit() {
    let x = ();
    let tokens = quote!(#x);
    let expected = "( )";
    assert_eq!(expected, tokens.as_str());
}

#[test]
fn test_tuple() {
    let x = ("foo", 4_u32);
    let tokens = quote!(#x);
    let expected = "( \"foo\" , 4u32 , )";
    assert_eq!(expected, tokens.as_str());
}

#[test]
fn test_array() {
    let x: [u32; 3] = [1, 2, 3];
    let tokens = quote!(#x);
    let expected = "[ 1u32 , 2u32 , 3u32 , ]";
    assert_eq!(expected, tokens.as_str());
}

#[test]
fn test_slice() {
    let x: &[u32] = &[1, 2, 3];
    let tokens = quote!(&#x);  // Note: explicit `&`
    let expected = "& [ 1u32 , 2u32 , 3u32 , ]";
    assert_eq!(expected, tokens.as_str());
}

#[test]
fn test_vec() {
    let x: Vec<u32> = vec![1, 2, 3];
    let tokens = quote!(vec!#x);  // Note: explicit `vec!`
    let expected = "vec ! [ 1u32 , 2u32 , 3u32 , ]";
    assert_eq!(expected, tokens.as_str());
}

#[test]
fn test_integer() {
    let ii8 = -1i8;
    let ii16 = -1i16;
    let ii32 = -1i32;
    let ii64 = -1i64;
    let iisize = -1isize;
    let uu8 = 1u8;
    let uu16 = 1u16;
    let uu32 = 1u32;
    let uu64 = 1u64;
    let uusize = 1usize;

    let tokens = quote! {
        #ii8 #ii16 #ii32 #ii64 #iisize
        #uu8 #uu16 #uu32 #uu64 #uusize
    };
    let expected = "-1i8 -1i16 -1i32 -1i64 -1isize 1u8 1u16 1u32 1u64 1usize";
    assert_eq!(expected, tokens.as_str());
}

#[test]
fn test_hex() {
    let hex = quote::Hex(0xFFFF_0000_u32);
    let tokens = quote!(#hex);
    let expected = "0xFFFF0000u32";
    assert_eq!(expected, tokens.as_str());
}

#[test]
fn test_floating() {
    let e32 = 2.71828f32;
    let nan32 = f32::NAN;
    let inf32 = f32::INFINITY;
    let neginf32 = f32::NEG_INFINITY;

    let e64 = 2.71828f64;
    let nan64 = f64::NAN;
    let inf64 = f64::INFINITY;
    let neginf64 = f64::NEG_INFINITY;

    let tokens = quote! {
        #e32 @ #nan32 @ #inf32 @ #neginf32
        #e64 @ #nan64 @ #inf64 @ #neginf64
    };
    let expected = concat!(
        "2.71828f32 @ :: std :: f32 :: NAN @ :: std :: f32 :: INFINITY @ :: std :: f32 :: NEG_INFINITY ",
        "2.71828f64 @ :: std :: f64 :: NAN @ :: std :: f64 :: INFINITY @ :: std :: f64 :: NEG_INFINITY",
    );
    assert_eq!(expected, tokens.as_str());
}

#[test]
fn test_char() {
    let zero = '\0';
    let pound = '#';
    let quote = '"';
    let apost = '\'';
    let newline = '\n';
    let heart = '\u{2764}';

    let tokens = quote! {
        #zero #pound #quote #apost #newline #heart
    };
    let expected = "'\\0' '#' '\"' '\\'' '\\n' '\u{2764}'";
    assert_eq!(expected, tokens.as_str());
}

#[test]
fn test_str() {
    let s = "\0 a 'b \" c";
    let tokens = quote!(#s);
    let expected = "\"\\0 a 'b \\\" c\"";
    assert_eq!(expected, tokens.as_str());
}

#[test]
fn test_string() {
    let s = "\0 a 'b \" c".to_string();
    let tokens = quote!(#s);
    let expected = "\"\\0 a 'b \\\" c\"";
    assert_eq!(expected, tokens.as_str());
}

#[test]
fn test_byte_str() {
    let s = quote::ByteStr("\0 a 'b \" c");
    let tokens = quote!(#s);
    let expected = "b\"\\0 a 'b \\\" c\"";
    assert_eq!(expected, tokens.as_str());
}

#[test]
fn test_byte_str_escape() {
    let s = quote::ByteStr("\u{3c3} \\ \" \n");
    let tokens = quote!(#s);
    let expected = "b\"\\xCF\\x83 \\\\ \\\" \\n\"";
    assert_eq!(expected, tokens.as_str());
}

#[test]
fn test_ident() {
    let foo = quote::Ident::from("Foo");
    let bar = quote::Ident::from(format!("Bar{}", 7));
    let tokens = quote!(struct #foo; enum #bar {});
    let expected = "struct Foo ; enum Bar7 { }";
    assert_eq!(expected, tokens.as_str());
}

#[test]
fn test_duplicate() {
    let ch = 'x';

    let tokens = quote!(#ch #ch);

    let expected = "'x' 'x'";
    assert_eq!(expected, tokens.as_str());
}

#[test]
fn test_fancy_repetition() {
    let foo = vec!["a", "b"];
    let bar = vec![true, false];

    let tokens = quote! {
        #(#foo: #bar),*
    };

    let expected = r#""a" : true , "b" : false"#;
    assert_eq!(expected, tokens.as_str());
}

#[test]
fn test_nested_fancy_repetition() {
    let nested = vec![vec!['a', 'b', 'c'], vec!['x', 'y', 'z']];

    let tokens = quote! {
        #(
            #(#nested)*
        ),*
    };

    let expected = "'a' 'b' 'c' , 'x' 'y' 'z'";
    assert_eq!(expected, tokens.as_str());
}

#[test]
fn test_empty_repetition() {
    let tokens = quote!(#(a b)* #(c d),*);
    assert_eq!("", tokens.as_str());
}

#[test]
fn test_variable_name_conflict() {
    // The implementation of `#(...),*` uses the variable `_i` but it should be
    // fine, if a little confusing when debugging.
    let _i = vec!['a', 'b'];
    let tokens = quote! { #(#_i),* };
    let expected = "'a' , 'b'";
    assert_eq!(expected, tokens.as_str());
}

#[test]
fn test_empty_quote() {
    let tokens = quote!();
    assert_eq!("", tokens.as_str());
}

#[test]
fn test_box_str() {
    let b = "str".to_owned().into_boxed_str();
    let tokens = quote! { #b };
    assert_eq!("\"str\"", tokens.as_str());
}

#[test]
fn test_cow() {
    let owned: Cow<quote::Ident> = Cow::Owned(quote::Ident::from("owned"));

    let ident = quote::Ident::from("borrowed");
    let borrowed = Cow::Borrowed(&ident);

    let tokens = quote! { #owned #borrowed };
    assert_eq!("owned borrowed", tokens.as_str());
}

#[test]
fn test_closure() {
    fn field_i(i: usize) -> quote::Ident {
        quote::Ident::new(format!("__field{}", i))
    }

    let fields = (0usize..3)
        .map(field_i as fn(_) -> _)
        .map(|var| quote! { #var });

    let tokens = quote! { #(#fields)* };
    assert_eq!("__field0 __field1 __field2", tokens.as_str());
}