Consider empty url case when loading image

third_party/WebKit/Source/web/tests/WebFrameTest.cpp

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  *
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@@ skipping 12031 matching lines @@
   child->LoadRequest(WebURLRequest(BlankURL()));
 
   // Failing the original child frame navigation and trying to render fallback
   // content shouldn't crash. It should return NoLoadInProgress. This is so the
   // caller won't attempt to replace the correctly empty frame with an error
   // page.
   EXPECT_EQ(WebLocalFrame::NoLoadInProgress,
             child->MaybeRenderFallbackContent(WebURLError()));
 }
 
+TEST_F(WebFrameTest, AltTextOnAboutBlankPage) {
+  FrameTestHelpers::WebViewHelper web_view_helper;
+  web_view_helper.InitializeAndLoad("about:blank", true);
+  // We set the size because it impacts line wrapping, which changes the
+  // resulting text value.
+  web_view_helper.Resize(WebSize(640, 480));
+
+  // Generate a simple test case.
+  const char kSource[] =
+      "<img src='foo' alt='foo alt' width='200' height='200'>";
+  FrameTestHelpers::LoadHTMLString(web_view_helper.WebView()->MainFrameImpl(),
+                                   kSource, ToKURL("about:blank"));
+
+  web_view_helper.WebView()->UpdateAllLifecyclePhases();
+  RunPendingTasks();
+
+  // Make sure it comes out OK.
+  std::string text = WebFrameContentDumper::DumpLayoutTreeAsText(

[dmazzoni, 2017/05/16 21:08:06]

I think this is not a good fit for a unit test that
lives in Source/web/tests, because my understanding is
that those tests are supposed to use public apis, and
DumpLayoutTreeAsText is kind of a big hammer.

Options:
1. Just make it a layout test - that doesn't seem
unreasonable to me

2. Write a unit test inside core/ so you can access
the LayoutText directly and assert - maybe use
core/layout/ImageQualityControllerTest.cpp as a
guide?

[dmazzoni, 2017/05/16 21:10:43]

Maybe I'm wrong - if accessing a LayoutObject is
fine from this directory, then I'd suggest finding
the Element using GetElementById(), then getting its
layout object, then asserting that it has a LayoutText
child with the alt text.

+                         web_view_helper.WebView()->MainFrameImpl(),
+                         WebFrameContentDumper::kLayoutAsTextPrinting)
+                         .Utf8();
+  EXPECT_NE(std::string::npos, text.find("foo alt"));
+}
+
 }  // namespace blink