os: add ExitCode method to ProcessState

Fixes #26539

Change-Id: I6d403c1bbb552e1f1bdcc09a7ccd60b50617e0fc
GitHub-Last-Rev: 0b5262df5d99504523fd7a4665cb70a3cc6b0a09
GitHub-Pull-Request: golang/go#26544
Reviewed-on: https://go-review.googlesource.com/125443
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

1 files changed, 43 insertions, 0 deletions

diff --git a/src/os/exec/exec_test.go b/src/os/exec/exec_test.go
index 7bb230806f..f0bba11c5a 100644
--- a/src/os/exec/exec_test.go
+++ b/src/os/exec/exec_test.go
@@ -168,6 +168,49 @@ func TestExitStatus(t *testing.T) {
 	}
 }
 
+func TestExitCode(t *testing.T) {
+	// Test that exit code are returned correctly
+	cmd := helperCommand(t, "exit", "42")
+	cmd.Run()
+	want := 42
+	got := cmd.ProcessState.ExitCode()
+	if want != got {
+		t.Errorf("ExitCode got %d, want %d", got, want)
+	}
+
+	cmd = helperCommand(t, "/no-exist-executable")
+	cmd.Run()
+	want = 2
+	got = cmd.ProcessState.ExitCode()
+	if want != got {
+		t.Errorf("ExitCode got %d, want %d", got, want)
+	}
+
+	cmd = helperCommand(t, "exit", "255")
+	cmd.Run()
+	want = 255
+	got = cmd.ProcessState.ExitCode()
+	if want != got {
+		t.Errorf("ExitCode got %d, want %d", got, want)
+	}
+
+	cmd = helperCommand(t, "cat")
+	cmd.Run()
+	want = 0
+	got = cmd.ProcessState.ExitCode()
+	if want != got {
+		t.Errorf("ExitCode got %d, want %d", got, want)
+	}
+
+	// Test when command does not call Run().
+	cmd = helperCommand(t, "cat")
+	want = -1
+	got = cmd.ProcessState.ExitCode()
+	if want != got {
+		t.Errorf("ExitCode got %d, want %d", got, want)
+	}
+}
+
 func TestPipes(t *testing.T) {
 	check := func(what string, err error) {
 		if err != nil {