C++: Move preprocessor settings handling to the document.

This cleans up the handling of those settings, and makes sure that the
C++ document is setting those settings before parsing. This also
prevents lock contention in the parser, because before this patch the
document would kick of the initial parse (after opening a document),
after which the editor would come in and try to set the preprocessor
settings, resulting in the UI thread locking until the initial parse was
done.

Change-Id: Ia2e18a9667e10279f045c1c5849046ec4cfe85ae
Reviewed-by: Nikolai Kosjar <nikolai.kosjar@digia.com>

src/plugins/cppeditor/cppeditordocument.cpp

@@ -32,6 +32,7 @@
 #include "cppeditorconstants.h"
 #include "cpphighlighter.h"
 
+#include <cpptools/baseeditordocumentparser.h>
 #include <cpptools/builtineditordocumentprocessor.h>
 #include <cpptools/cppcodeformatter.h>
 #include <cpptools/cppcodemodelsettings.h>
@@ -40,6 +41,8 @@
 #include <cpptools/cpptoolsconstants.h>
 #include <cpptools/cpptoolsplugin.h>
 
+#include <projectexplorer/session.h>
+
 #include <utils/qtcassert.h>
 #include <utils/runextensions.h>
 
@@ -206,6 +209,7 @@ void CppEditorDocument::onFilePathChanged(const QString &oldPath, const QString
         m_editorDocumentHandle.reset(new CppEditorDocumentHandle(this));
 
         resetProcessor();
+        updatePreprocessorSettings();
         m_processorRevision = document()->revision();
         processDocument();
     }
@@ -237,6 +241,34 @@ void CppEditorDocument::resetProcessor()
     processor(); // creates a new processor
 }
 
+void CppEditorDocument::updatePreprocessorSettings()
+{
+    if (filePath().isEmpty())
+        return;
+
+    const QString prefix = QLatin1String(Constants::CPP_PREPROCESSOR_PROJECT_PREFIX);
+    const QString &projectFile = ProjectExplorer::SessionManager::value(
+                prefix + filePath()).toString();
+    const QString directivesKey = projectFile + QLatin1Char(',') + filePath();
+    const QByteArray additionalDirectives = ProjectExplorer::SessionManager::value(
+                directivesKey).toString().toUtf8();
+
+    setPreprocessorSettings(mm()->projectPartForProjectFile(projectFile), additionalDirectives);
+}
+
+void CppEditorDocument::setPreprocessorSettings(const CppTools::ProjectPart::Ptr &projectPart,
+                                                const QByteArray &defines)
+{
+    CppTools::BaseEditorDocumentParser *parser = processor()->parser();
+    QTC_ASSERT(parser, return);
+    if (parser->projectPart() != projectPart || parser->editorDefines() != defines) {
+        parser->setProjectPart(projectPart);
+        parser->setEditorDefines(defines);
+
+        emit preprocessorSettingsChanged(!defines.trimmed().isEmpty());
+    }
+}
+
 unsigned CppEditorDocument::contentsRevision() const
 {
     return document()->revision();