t.Fatalf("Output didn't match for 'istioctl %s'\n got %v\nwant: %v", strings.Join(c.args, " "), output, c.expectedString)
	}

	if c.wantException {
		if fErr == nil {
			t.Fatalf("Wanted an exception for 'istioctl %s', didn't get one, output was %q",
				strings.Join(c.args, " "), output)
		}
	} else {
		if fErr != nil {