t.Fatalf("Unexpected output for 'istioctl %s'\n got: %q\nwant: %q", strings.Join(c.args, " "), output, c.expectedOutput)
	}

	if c.expectedString != "" && !strings.Contains(output, c.expectedString) {
		t.Fatalf("Output didn't match for '%s %s'\n got %v\nwant: %v", cmd.Name(), strings.Join(c.args, " "), output, c.expectedString)
	}

	if c.wantException {
		if fErr == nil {

		t.Fatalf("Unexpected output for 'istioctl %s'\n got: %q\nwant: %q", strings.Join(c.args, " "), output, c.expectedOutput)
	}

	if c.expectedString != "" && !strings.Contains(output, c.expectedString) {
		t.Fatalf("Output didn't match for '%s %s'\n got %v\nwant: %v", cmd.Name(), strings.Join(c.args, " "), output, c.expectedString)
	}

	if c.wantException {
		if fErr == nil {

	c.Assert(response.StatusCode, http.StatusOK)

	// test Cases containing data to make partial range requests.
	// also has expected response data.
	testCases := []struct {
		byteRange      string
		expectedString string
	}{
		// request for byte range 10-11.
		// expecting the result to contain only putContent[10:12] bytes.
		{"10-11", putContent[10:12]},
		// request for object data after the first byte.