Update tests for new YAMLIO polymorphic traits

[scott.linder]

Summary

See https://reviews.llvm.org/D48144 for the LLVM patch.

[nhaehnle]

Adding @tpr as a subscriber due to the (admittedly maybe a bit indirect) MsgPack connection.

[scott.linder]

Rebase

@klimek is there anyone I should add to take a look at this? As far as the YAML is concerned I believe this is a non-functional change.

[scott.linder]

r346884

[scott.linder]

r346884

unittests/Tooling/DiagnosticsYamlTest.cpp

EXPECT_EQ("---\n"
             "      - FilePath:        'path/to/header.h'\n"
             "        Offset:          62\n"
             "        Length:          2\n"
             "        ReplacementText: 'replacement #2'\n"
             "  - DiagnosticName:  'diagnostic#3'\n"
             "    Message:         'message #3'\n"
             "    FileOffset:      72\n"
             "    FilePath:        'path/to/source2.cpp'\n"
-            "    Replacements:    \n"
+            "    Replacements:    []\n"
             "...\n",
             YamlContentStream.str());
 }
 
 TEST(DiagnosticsYamlTest, deserializesDiagnostics) {
   std::string YamlContent = "---\n"
                             "MainSourceFile:  path/to/source.cpp\n"
                             "Diagnostics:     \n"
std::string YamlContent = "---\n"
                             "      - FilePath:        path/to/header.h\n"
                             "        Offset:          62\n"
                             "        Length:          2\n"
                             "        ReplacementText: 'replacement #2'\n"
                             "  - DiagnosticName:  'diagnostic#3'\n"
                             "    Message:         'message #3'\n"
                             "    FileOffset:      98\n"
                             "    FilePath:        path/to/source.cpp\n"
-                            "    Replacements:    \n"
+                            "    Replacements:    []\n"
                             "...\n";
   TranslationUnitDiagnostics TUDActual;
   yaml::Input YAML(YamlContent);
   YAML >> TUDActual;
 
   ASSERT_FALSE(YAML.error());
   ASSERT_EQ(3u, TUDActual.Diagnostics.size());
   EXPECT_EQ("path/to/source.cpp", TUDActual.MainSourceFile);

unittests/Tooling/RefactoringActionRulesTest.cpp

// When the requirements are satisfied, the rule's function must be invoked.
     ASSERT_EQ(Result.size(), 1u);
     std::string YAMLString =
         const_cast<AtomicChange &>(Result[0]).toYAMLString();
 
     ASSERT_STREQ("---\n"
                  "Key:             'input.cpp:30'\n"
                  "FilePath:        input.cpp\n"
                  "Error:           ''\n"
-                 "InsertedHeaders: \n"
-                 "RemovedHeaders:  \n"
+                 "InsertedHeaders: []\n"
+                 "RemovedHeaders:  []\n"
                  "Replacements:    \n" // Extra whitespace here!
                  "  - FilePath:        input.cpp\n"
                  "    Offset:          30\n"
                  "    Length:          1\n"
                  "    ReplacementText: b\n"
                  "...\n",
                  YAMLString.c_str());
   }