Clang: Filter macro QT_TESTCASE_BUILDDIR out

We have to universalize it later with a UI so that user can set their
own macros.

Change-Id: I5385c3c1b01dbf77a1cbc2431103fcdea3f96118
Reviewed-by: Tim Jenssen <tim.jenssen@qt.io>
Reviewed-by: Cristian Adam <cristian.adam@qt.io>

src/plugins/clangpchmanager/projectupdater.cpp

@@ -156,6 +156,7 @@ QStringList ProjectUpdater::toolChainArguments(CppTools::ProjectPart *projectPar
     // builder.addTargetTriple(); TODO resarch why target triples are different
     builder.addExtraCodeModelFlags();
     builder.undefineClangVersionMacrosForMsvc();
+
     builder.undefineCppLanguageFeatureMacrosForMsvc2015();
     builder.addProjectConfigFileInclude();
     builder.addMsvcCompatibilityVersion();
@@ -163,6 +164,19 @@ QStringList ProjectUpdater::toolChainArguments(CppTools::ProjectPart *projectPar
     return builder.options();
 }
 
+namespace {
+void cleanupMacros(ClangBackEnd::CompilerMacros &macros)
+{
+    auto newEnd = std::partition(macros.begin(),
+                                 macros.end(),
+                                 [](const ClangBackEnd::CompilerMacro &macro) {
+                                     return macro.key != "QT_TESTCASE_BUILDDIR";
+                                 });
+
+    macros.erase(newEnd, macros.end());
+}
+} // namespace
+
 ClangBackEnd::CompilerMacros ProjectUpdater::createCompilerMacros(const ProjectExplorer::Macros &projectMacros)
 {
     int index = 0;
@@ -171,6 +185,8 @@ ClangBackEnd::CompilerMacros ProjectUpdater::createCompilerMacros(const ProjectE
             return ClangBackEnd::CompilerMacro{macro.key, macro.value, ++index};
         });
 
+    cleanupMacros(macros);
+
     std::sort(macros.begin(), macros.end());
 
     return macros;

tests/unit/unittest/projectupdater-test.cpp

@@ -310,6 +310,14 @@ TEST_F(ProjectUpdater, CreateSortedCompilerMacros)
                                    CompilerMacro{"DEFINE", "1", 3}));
 }
 
+TEST_F(ProjectUpdater, FilterCompilerMacros)
+{
+    auto paths = updater.createCompilerMacros(
+        {{"DEFINE", "1"}, {"QT_TESTCASE_BUILDDIR", "2"}, {"BAR", "1"}});
+
+    ASSERT_THAT(paths, ElementsAre(CompilerMacro{"BAR", "1", 1}, CompilerMacro{"DEFINE", "1", 3}));
+}
+
 TEST_F(ProjectUpdater, CreateSortedIncludeSearchPaths)
 {
     CppTools::ProjectPart projectPart;