|  | // Copyright 2015 The Go Authors. All rights reserved. | 
|  | // Use of this source code is governed by a BSD-style | 
|  | // license that can be found in the LICENSE file. | 
|  |  | 
|  | package runtime_test | 
|  |  | 
|  | import ( | 
|  | "runtime" | 
|  | "syscall" | 
|  | "testing" | 
|  | ) | 
|  |  | 
|  | func TestFixedGOROOT(t *testing.T) { | 
|  | // Restore both the real GOROOT environment variable, and runtime's copies: | 
|  | if orig, ok := syscall.Getenv("GOROOT"); ok { | 
|  | defer syscall.Setenv("GOROOT", orig) | 
|  | } else { | 
|  | defer syscall.Unsetenv("GOROOT") | 
|  | } | 
|  | envs := runtime.Envs() | 
|  | oldenvs := append([]string{}, envs...) | 
|  | defer runtime.SetEnvs(oldenvs) | 
|  |  | 
|  | // attempt to reuse existing envs backing array. | 
|  | want := runtime.GOROOT() | 
|  | runtime.SetEnvs(append(envs[:0], "GOROOT="+want)) | 
|  |  | 
|  | if got := runtime.GOROOT(); got != want { | 
|  | t.Errorf(`initial runtime.GOROOT()=%q, want %q`, got, want) | 
|  | } | 
|  | if err := syscall.Setenv("GOROOT", "/os"); err != nil { | 
|  | t.Fatal(err) | 
|  | } | 
|  | if got := runtime.GOROOT(); got != want { | 
|  | t.Errorf(`after setenv runtime.GOROOT()=%q, want %q`, got, want) | 
|  | } | 
|  | if err := syscall.Unsetenv("GOROOT"); err != nil { | 
|  | t.Fatal(err) | 
|  | } | 
|  | if got := runtime.GOROOT(); got != want { | 
|  | t.Errorf(`after unsetenv runtime.GOROOT()=%q, want %q`, got, want) | 
|  | } | 
|  | } |