if err != nil {
		t.Errorf("echo: %v", err)
	}
	if g, e := string(bs), "foo bar baz\n"; g != e {
		t.Errorf("echo: want %q, got %q", e, g)
	}
}

func TestCommandRelativeName(t *testing.T) {
	t.Parallel()

	cmd := helperCommand(t, "echo", "foo")

	// Run our own binary as a relative path
	// (e.g. "_test/exec.test") our parent directory.