--- /dev/null
+// Copyright 2017 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 main
+
+import (
+ "errors"
+ "os"
+ "os/exec"
+ "runtime"
+ "testing"
+)
+
+func TestExpandUser(t *testing.T) {
+ env := "HOME"
+ if runtime.GOOS == "windows" {
+ env = "USERPROFILE"
+ } else if runtime.GOOS == "plan9" {
+ env = "home"
+ }
+
+ oldenv := os.Getenv(env)
+ os.Setenv(env, "/home/gopher")
+ defer os.Setenv(env, oldenv)
+
+ tests := []struct {
+ input string
+ want string
+ }{
+ {input: "~/foo", want: "/home/gopher/foo"},
+ {input: "${HOME}/foo", want: "/home/gopher/foo"},
+ {input: "/~/foo", want: "/~/foo"},
+ }
+ for _, tt := range tests {
+ got := expandUser(tt.input)
+ if got != tt.want {
+ t.Fatalf("want %q, but %q", tt.want, got)
+ }
+ }
+}
+
+func TestCmdErr(t *testing.T) {
+ tests := []struct {
+ input error
+ want string
+ }{
+ {input: errors.New("cmd error"), want: "cmd error"},
+ {input: &exec.ExitError{ProcessState: nil, Stderr: nil}, want: "<nil>"},
+ {input: &exec.ExitError{ProcessState: nil, Stderr: []byte("test")}, want: "<nil>: test"},
+ }
+
+ for i, tt := range tests {
+ got := cmdErr(tt.input)
+ if got != tt.want {
+ t.Fatalf("%d. got %q, want %q", i, got, tt.want)
+ }
+ }
+}