| Brad Fitzpatrick | 39ad208 | 2018-06-12 16:16:38 +0000 | [diff] [blame] | 1 | // run |
| 2 | |
| 3 | // Copyright 2018 The Go Authors. All rights reserved. |
| 4 | // Use of this source code is governed by a BSD-style |
| 5 | // license that can be found in the LICENSE file. |
| 6 | |
| 7 | // Test that string([]byte(string)) makes a copy and doesn't reduce to |
| 8 | // nothing. (Issue 25834) |
| 9 | |
| 10 | package main |
| 11 | |
| 12 | import ( |
| 13 | "reflect" |
| 14 | "unsafe" |
| 15 | ) |
| 16 | |
| 17 | func main() { |
| 18 | var ( |
| 19 | buf = make([]byte, 2<<10) |
| 20 | large = string(buf) |
| 21 | sub = large[10:12] |
| 22 | subcopy = string([]byte(sub)) |
| 23 | subh = *(*reflect.StringHeader)(unsafe.Pointer(&sub)) |
| 24 | subcopyh = *(*reflect.StringHeader)(unsafe.Pointer(&subcopy)) |
| 25 | ) |
| 26 | if subh.Data == subcopyh.Data { |
| 27 | panic("sub and subcopy have the same underlying array") |
| 28 | } |
| 29 | } |