all: use testenv.Executable instead of os.Executable and os.Args[0]

In test files, using testenv.Executable is more reliable than
os.Executable or os.Args[0].

Change-Id: I88e577efeabc20d02ada27bf706ae4523129128e
Reviewed-on: https://go-review.googlesource.com/c/go/+/651955
Reviewed-by: Cherry Mui <cherryyz@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>

2 files changed, 8 insertions, 8 deletions

diff --git a/src/os/pipe_test.go b/src/os/pipe_test.go
index a9e0c8bc8a..ccae6f61bf 100644
--- a/src/os/pipe_test.go
+++ b/src/os/pipe_test.go
@@ -118,7 +118,7 @@ func TestStdPipe(t *testing.T) {
 	// all writes should fail with EPIPE and then exit 0.
 	for _, sig := range []bool{false, true} {
 		for dest := 1; dest < 4; dest++ {
-			cmd := testenv.Command(t, os.Args[0], "-test.run", "TestStdPipe")
+			cmd := testenv.Command(t, testenv.Executable(t), "-test.run", "TestStdPipe")
 			cmd.Stdout = w
 			cmd.Stderr = w
 			cmd.ExtraFiles = []*os.File{w}
@@ -145,7 +145,7 @@ func TestStdPipe(t *testing.T) {
 	}
 
 	// Test redirecting stdout but not stderr.  Issue 40076.
-	cmd := testenv.Command(t, os.Args[0], "-test.run", "TestStdPipe")
+	cmd := testenv.Command(t, testenv.Executable(t), "-test.run", "TestStdPipe")
 	cmd.Stdout = w
 	var stderr bytes.Buffer
 	cmd.Stderr = &stderr
@@ -263,7 +263,7 @@ func TestReadNonblockingFd(t *testing.T) {
 	}
 	defer r.Close()
 	defer w.Close()
-	cmd := testenv.Command(t, os.Args[0], "-test.run=^"+t.Name()+"$")
+	cmd := testenv.Command(t, testenv.Executable(t), "-test.run=^"+t.Name()+"$")
 	cmd.Env = append(cmd.Environ(), "GO_WANT_READ_NONBLOCKING_FD=1")
 	cmd.Stdin = r
 	output, err := cmd.CombinedOutput()
diff --git a/src/os/signal/signal_test.go b/src/os/signal/signal_test.go
index d54787bc19..0aa0439b90 100644
--- a/src/os/signal/signal_test.go
+++ b/src/os/signal/signal_test.go
@@ -304,7 +304,7 @@ func TestDetectNohup(t *testing.T) {
 		// We have no intention of reading from c.
 		c := make(chan os.Signal, 1)
 		Notify(c, syscall.SIGHUP)
-		if out, err := testenv.Command(t, os.Args[0], "-test.run=^TestDetectNohup$", "-check_sighup_ignored").CombinedOutput(); err == nil {
+		if out, err := testenv.Command(t, testenv.Executable(t), "-test.run=^TestDetectNohup$", "-check_sighup_ignored").CombinedOutput(); err == nil {
 			t.Errorf("ran test with -check_sighup_ignored and it succeeded: expected failure.\nOutput:\n%s", out)
 		}
 		Stop(c)
@@ -316,7 +316,7 @@ func TestDetectNohup(t *testing.T) {
 		}
 		Ignore(syscall.SIGHUP)
 		os.Remove("nohup.out")
-		out, err := testenv.Command(t, "/usr/bin/nohup", os.Args[0], "-test.run=^TestDetectNohup$", "-check_sighup_ignored").CombinedOutput()
+		out, err := testenv.Command(t, "/usr/bin/nohup", testenv.Executable(t), "-test.run=^TestDetectNohup$", "-check_sighup_ignored").CombinedOutput()
 
 		data, _ := os.ReadFile("nohup.out")
 		os.Remove("nohup.out")
@@ -454,7 +454,7 @@ func TestNohup(t *testing.T) {
 				if subTimeout != 0 {
 					args = append(args, fmt.Sprintf("-test.timeout=%v", subTimeout))
 				}
-				out, err := testenv.Command(t, os.Args[0], args...).CombinedOutput()
+				out, err := testenv.Command(t, testenv.Executable(t), args...).CombinedOutput()
 
 				if err == nil {
 					t.Errorf("ran test with -send_uncaught_sighup=%d and it succeeded: expected failure.\nOutput:\n%s", i, out)
@@ -562,7 +562,7 @@ func TestAtomicStop(t *testing.T) {
 		if deadline, ok := t.Deadline(); ok {
 			timeout = time.Until(deadline).String()
 		}
-		cmd := testenv.Command(t, os.Args[0], "-test.run=^TestAtomicStop$", "-test.timeout="+timeout)
+		cmd := testenv.Command(t, testenv.Executable(t), "-test.run=^TestAtomicStop$", "-test.timeout="+timeout)
 		cmd.Env = append(os.Environ(), "GO_TEST_ATOMIC_STOP=1")
 		out, err := cmd.CombinedOutput()
 		if err == nil {
@@ -765,7 +765,7 @@ func TestNotifyContextNotifications(t *testing.T) {
 			if subTimeout != 0 {
 				args = append(args, fmt.Sprintf("-test.timeout=%v", subTimeout))
 			}
-			out, err := testenv.Command(t, os.Args[0], args...).CombinedOutput()
+			out, err := testenv.Command(t, testenv.Executable(t), args...).CombinedOutput()
 			if err != nil {
 				t.Errorf("ran test with -check_notify_ctx_notification and it failed with %v.\nOutput:\n%s", err, out)
 			}