MHTMLTest::TestMHTMLEncoding checks generated MTHML is well formed.

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

Index: third_party/WebKit/Source/web/tests/MHTMLTest.cpp
diff --git a/third_party/WebKit/Source/web/tests/MHTMLTest.cpp b/third_party/WebKit/Source/web/tests/MHTMLTest.cpp
index 494f0713505ffc3e915dcbb684d4756014b7332f..c8c1aa536a2f2de9cd3db72bdaceda6068ecc457 100644
--- a/third_party/WebKit/Source/web/tests/MHTMLTest.cpp
+++ b/third_party/WebKit/Source/web/tests/MHTMLTest.cpp
@@ -35,6 +35,7 @@
 #include "platform/SerializedResource.h"
 #include "platform/SharedBuffer.h"
 #include "platform/mhtml/MHTMLArchive.h"
+#include "platform/mhtml/MHTMLParser.h"
 #include "platform/testing/URLTestHelpers.h"
 #include "platform/testing/UnitTestHelpers.h"
 #include "platform/weborigin/KURL.h"
@@ -161,6 +162,13 @@ class MHTMLTest : public ::testing::Test {
     }
     MHTMLArchive::GenerateMHTMLFooterForTesting(boundary,
                                                 *mhtml_data->MutableData());
+
+    // Validate the generated MHTML.
+    MHTMLParser parser(
+        SharedBuffer::Create(mhtml_data->data(), mhtml_data->length()));
+    if (parser.ParseArchive().IsEmpty())
+      return RawData::Create();

[Łukasz Anforowicz, 2017/04/25 20:00:45]

Would it be okay if the above said:

    if (parser.ParseArchive().IsEmpty()) {
      ADD_FAILURE() << "Invalid MHTML";
      return RawData::Create();
    }

This way all callers of MHTMLArchive::GenerateMHTMLFooterForTesting will go
through verification that the generated mhtml is well-formed.

[carlosk, 2017/04/25 20:18:15]

Done.

+
     return mhtml_data.Release();
   }
 
@@ -206,6 +214,7 @@ TEST_F(MHTMLTest, TestMHTMLEncoding) {
   AddTestResources();
   RefPtr<RawData> data = Serialize("Test Serialization", "text/html",
                                    MHTMLArchive::kUseDefaultEncoding);
+  ASSERT_GT(data->length(), 0u) << "Invalid MHTML";
 
   // Read the MHTML data line per line and do some pseudo-parsing to make sure
   // the right encoding is used for the different sections.
@@ -242,6 +251,8 @@ TEST_F(MHTMLTest, MHTMLFromScheme) {
   AddTestResources();
   RefPtr<RawData> raw_data = Serialize("Test Serialization", "text/html",
                                        MHTMLArchive::kUseDefaultEncoding);
+  ASSERT_GT(raw_data->length(), 0u) << "Invalid MHTML";
+
   RefPtr<SharedBuffer> data =
       SharedBuffer::Create(raw_data->data(), raw_data->length());
   KURL http_url = ToKURL("http://www.example.com");