[ios] TextBadgeView interface, implementation, and unit test stubs

ios/chrome/browser/ui/reading_list/text_badge_view_unittest.mm

+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#import "ios/chrome/browser/ui/reading_list/text_badge_view.h"
+#import <Foundation/Foundation.h>

[edchin, 2017/06/28 00:38:24]

There should be a space after the first import and the frameworks imports.

[helenlyang, 2017/06/28 15:25:07]

Done.

+
+#include "testing/gtest/include/gtest/gtest.h"
+#include "testing/gtest_mac.h"

[edchin, 2017/06/28 00:38:24]

This has the macro EXPECT_NSEQ(). I'm sure you're going to need it when you
implement this method. 
But this isn't quite needed yet. It's our policy to only introduce includes that
are actually used in the CL.

+
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
+// Tests that badge should be hidden if the label is nil.
+TEST(TextBadgeViewTest, BadgeWithoutLabel) {}

[edchin, 2017/06/28 00:38:23]

We can remove the first two tests since we think this is programmer error.

[helenlyang, 2017/06/28 15:25:07]

Done.

+
+// Tests that badge should be hidden if the label text is the empty string.
+TEST(TextBadgeViewTest, EmptyStringLabel) {}
+
+// Tests that badge width should resize to fit short display text.
+TEST(TextBadgeViewTest, BadgeWidthShortLabel) {}

[edchin, 2017/06/28 00:38:23]

We can test the intrinsic content size. I like this test. Please
update the comment to something like:
"Tests that the badge's intrinsic content size given a short text."
Please make a similar edit to the next test.

See the doc on intrinsicContentSize here:
https://developer.apple.com/documentation/uikit/uiview/1622600-intrinsicconte...

[helenlyang, 2017/06/28 15:25:07]

Done.

+
+// Tests that badge width should stretch to fit long display text.
+TEST(TextBadgeViewTest, BadgeWidthLongLabel) {}
+
+// Tests that text and layout flip for RTL languages.
+TEST(TextBadgeViewTest, RTL) {}

[edchin, 2017/06/28 00:38:23]

This is a good idea. I'm not sure how this is tested, but we can figure it out
when we implement this test.

+
+// Tests accessibility features.

[edchin, 2017/06/28 00:38:24]

This comment can be more specific. Consider something like this:
"Tests that the accessibility label matches the display text". 

[helenlyang, 2017/06/28 15:25:07]

Done.

+TEST(TextBadgeViewTest, Accessibility) {}