cmd/go: avoid setting variables for '/' and ':' in TestScript subprocess environments

Also simplify platform-dependent handling of the PATH variable,
to make it more like the existing platform-dependent handling for
HOME and TMPDIR.

Fixes #53671.

Change-Id: Ica2665d3f61988c66fb6982b9feb61ca48eced79
Reviewed-on: https://go-review.googlesource.com/c/go/+/416554
Reviewed-by: Ian Lance Taylor <iant@google.com>
Run-TryBot: Bryan Mills <bcmills@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>

diff --git a/src/cmd/go/go_test.go b/src/cmd/go/go_test.go
index b39a62f3e4cc1898536b13dbf21ce1aaad12d23c..c100316f478edd0e54901b1baefdd4c41996cbb2 100644 (file)
--- a/src/cmd/go/go_test.go
+++ b/src/cmd/go/go_test.go
@@ -1363,6 +1363,15 @@ func tempEnvName() string {
        }
 }
 
+func pathEnvName() string {
+       switch runtime.GOOS {
+       case "plan9":
+               return "path"
+       default:
+               return "PATH"
+       }
+}
+
 func TestDefaultGOPATH(t *testing.T) {
        tg := testgo(t)
        defer tg.cleanup()

diff --git a/src/cmd/go/script_test.go b/src/cmd/go/script_test.go
index 5e82929f19a5dd4bfe86110f44d8f92ddec551cf..809dfb452f36683ae7b700bb9da045a83141588c 100644 (file)
--- a/src/cmd/go/script_test.go
+++ b/src/cmd/go/script_test.go
@@ -163,7 +163,7 @@ func (ts *testScript) setup() {
        ts.cd = filepath.Join(ts.workdir, "gopath/src")
        ts.env = []string{
                "WORK=" + ts.workdir, // must be first for ts.abbrev
-               "PATH=" + testBin + string(filepath.ListSeparator) + os.Getenv("PATH"),
+               pathEnvName() + "=" + testBin + string(filepath.ListSeparator) + os.Getenv(pathEnvName()),
                homeEnvName() + "=/no-home",
                "CCACHE_DISABLE=1", // ccache breaks with non-existent HOME
                "GOARCH=" + runtime.GOARCH,
@@ -187,8 +187,6 @@ func (ts *testScript) setup() {
                tempEnvName() + "=" + filepath.Join(ts.workdir, "tmp"),
                "devnull=" + os.DevNull,
                "goversion=" + goVersion(ts),
-               ":=" + string(os.PathListSeparator),
-               "/=" + string(os.PathSeparator),
                "CMDGO_TEST_RUN_MAIN=true",
        }
        if testenv.Builder() != "" || os.Getenv("GIT_TRACE_CURL") == "1" {
@@ -203,10 +201,6 @@ func (ts *testScript) setup() {
                ts.env = append(ts.env, "TESTGONETWORK=panic", "TESTGOVCS=panic")
        }
 
-       if runtime.GOOS == "plan9" {
-               ts.env = append(ts.env, "path="+testBin+string(filepath.ListSeparator)+os.Getenv("path"))
-       }
-
        for _, key := range extraEnvKeys {
                if val := os.Getenv(key); val != "" {
                        ts.env = append(ts.env, key+"="+val)
@@ -219,6 +213,10 @@ func (ts *testScript) setup() {
                        ts.envMap[kv[:i]] = kv[i+1:]
                }
        }
+       // Add entries for ${:} and ${/} to make it easier to write platform-independent
+       // environment variables.
+       ts.envMap["/"] = string(os.PathSeparator)
+       ts.envMap[":"] = string(os.PathListSeparator)
 
        fmt.Fprintf(&ts.log, "# (%s)\n", time.Now().UTC().Format(time.RFC3339))
        ts.mark = ts.log.Len()
@@ -1264,12 +1262,7 @@ func (ts *testScript) lookPath(command string) (string, error) {
                }
        }
 
-       pathName := "PATH"
-       if runtime.GOOS == "plan9" {
-               pathName = "path"
-       }
-
-       for _, dir := range strings.Split(ts.envMap[pathName], string(filepath.ListSeparator)) {
+       for _, dir := range strings.Split(ts.envMap[pathEnvName()], string(filepath.ListSeparator)) {
                if searchExt {
                        ents, err := os.ReadDir(dir)
                        if err != nil {

diff --git a/src/cmd/go/testdata/script/README b/src/cmd/go/testdata/script/README
index c575bff1a517fc3d9db781dbd161633f267ba6a1..e52917684f8c86c4fd9b8192de6e1f9ea2a082a9 100644 (file)
--- a/src/cmd/go/testdata/script/README
+++ b/src/cmd/go/testdata/script/README
@@ -41,12 +41,19 @@ Scripts also have access to these other environment variables:
        GODEBUG=<actual GODEBUG>
        devnull=<value of os.DevNull>
        goversion=<current Go version; for example, 1.12>
-       :=<OS-specific path list separator>
 
-The scripts' supporting files are unpacked relative to $GOPATH/src (aka $WORK/gopath/src)
-and then the script begins execution in that directory as well. Thus the example above runs
-in $WORK/gopath/src with GOPATH=$WORK/gopath and $WORK/gopath/src/hello.go
-containing the listed contents.
+On Plan 9, the variables $path and $home are set instead of $PATH and $HOME.
+On Windows, the variables $USERPROFILE and $TMP are set instead of
+$HOME and $TMPDIR.
+
+In addition, variables named ':' and '/' are expanded within script arguments
+(expanding to the value of os.PathListSeparator and os.PathSeparator
+respectively) but are not inherited in subprocess environments.
+
+The scripts' supporting files are unpacked relative to $GOPATH/src
+(aka $WORK/gopath/src) and then the script begins execution in that directory as
+well. Thus the example above runs in $WORK/gopath/src with GOPATH=$WORK/gopath
+and $WORK/gopath/src/hello.go containing the listed contents.
 
 The lines at the top of the script are a sequence of commands to be executed
 by a tiny script engine in ../../script_test.go (not the system shell).