os: add UserHomeDir

Fixes #26463

Change-Id: Iaef1c7456ffaeadeead6027a37d09c44a3d05bd5
Reviewed-on: https://go-review.googlesource.com/c/139418
Reviewed-by: Ian Lance Taylor <iant@golang.org>

diff --git a/src/os/example_test.go b/src/os/example_test.go
index 95a4a678171caad10c03cecade6a5b9d865f6dd6..5c96ebb417dcd258e842fed36fa113e1318c821e 100644 (file)
--- a/src/os/example_test.go
+++ b/src/os/example_test.go
@@ -76,32 +76,29 @@ func ExampleIsNotExist() {
        // file does not exist
 }
 
-func init() {
-       os.Setenv("USER", "gopher")
-       os.Setenv("HOME", "/usr/gopher")
-       os.Unsetenv("GOPATH")
-}
-
 func ExampleExpand() {
        mapper := func(placeholderName string) string {
                switch placeholderName {
                case "DAY_PART":
                        return "morning"
-               case "USER":
+               case "NAME":
                        return "Gopher"
                }
 
                return ""
        }
 
-       fmt.Println(os.Expand("Good ${DAY_PART}, $USER!", mapper))
+       fmt.Println(os.Expand("Good ${DAY_PART}, $NAME!", mapper))
 
        // Output:
        // Good morning, Gopher!
 }
 
 func ExampleExpandEnv() {
-       fmt.Println(os.ExpandEnv("$USER lives in ${HOME}."))
+       os.Setenv("NAME", "gopher")
+       os.Setenv("BURROW", "/usr/gopher")
+
+       fmt.Println(os.ExpandEnv("$NAME lives in ${BURROW}."))
 
        // Output:
        // gopher lives in /usr/gopher.
@@ -117,16 +114,24 @@ func ExampleLookupEnv() {
                }
        }
 
-       show("USER")
-       show("GOPATH")
+       os.Setenv("SOME_KEY", "value")
+       os.Setenv("EMPTY_KEY", "")
+
+       show("SOME_KEY")
+       show("EMPTY_KEY")
+       show("MISSING_KEY")
 
        // Output:
-       // USER=gopher
-       // GOPATH not set
+       // SOME_KEY=value
+       // EMPTY_KEY=
+       // MISSING_KEY not set
 }
 
 func ExampleGetenv() {
-       fmt.Printf("%s lives in %s.\n", os.Getenv("USER"), os.Getenv("HOME"))
+       os.Setenv("NAME", "gopher")
+       os.Setenv("BURROW", "/usr/gopher")
+
+       fmt.Printf("%s lives in %s.\n", os.Getenv("NAME"), os.Getenv("BURROW"))
 
        // Output:
        // gopher lives in /usr/gopher.

diff --git a/src/os/file.go b/src/os/file.go
index cba70d78fbfd32fc2baa57cc1d80ccc9ad4366f0..eb2277dece3407e6a2556ee45793e2e561d76eda 100644 (file)
--- a/src/os/file.go
+++ b/src/os/file.go
@@ -381,6 +381,24 @@ func UserCacheDir() (string, error) {
        return dir, nil
 }
 
+// UserHomeDir returns the current user's home directory.
+//
+// On Unix, including macOS, it returns the $HOME environment variable.
+// On Windows, it returns the concatenation of %HOMEDRIVE% and %HOMEPATH%.
+// On Plan 9, it returns the $home environment variable.
+func UserHomeDir() string {
+       if runtime.GOOS == "windows" {
+               return Getenv("HOMEDRIVE") + Getenv("HOMEPATH")
+       }
+       if runtime.GOOS == "plan9" {
+               return Getenv("home")
+       }
+       if runtime.GOOS == "nacl" {
+               return "/"
+       }
+       return Getenv("HOME")
+}
+
 // Chmod changes the mode of the named file to mode.
 // If the file is a symbolic link, it changes the mode of the link's target.
 // If there is an error, it will be of type *PathError.

diff --git a/src/os/os_test.go b/src/os/os_test.go
index 894105a886011edf2d46d301c72de9231d05c248..08853691a9664153743d1a7a1e2dfb873fac7668 100644 (file)
--- a/src/os/os_test.go
+++ b/src/os/os_test.go
@@ -2333,3 +2333,17 @@ func TestDoubleCloseError(t *testing.T) {
                t.Logf("second close returned expected error %q", err)
        }
 }
+
+func TestUserHomeDir(t *testing.T) {
+       dir := UserHomeDir()
+       if dir == "" {
+               t.Fatal("UserHomeDir returned an empty string")
+       }
+       fi, err := Stat(dir)
+       if err != nil {
+               t.Fatal(err)
+       }
+       if !fi.IsDir() {
+               t.Fatalf("dir %s is not directory; type = %v", dir, fi.Mode())
+       }
+}