Git: Fix branch expansion on show before the diff display is done

The description is shown first (with the <Expand> placeholder), and the
diff parsing can be long. If <Expand> is clicked during parsing, it fails
because the base directory is not set yet.

Change-Id: Ib5e839b292c32091c726f24eb643d0fa5a142cb7
Reviewed-by: André Hartmann <aha_1980@gmx.de>
Reviewed-by: Tobias Hunger <tobias.hunger@qt.io>

src/plugins/diffeditor/diffeditorcontroller.cpp

@@ -55,6 +55,11 @@ QString DiffEditorController::baseDirectory() const
     return m_document->baseDirectory();
 }
 
+void DiffEditorController::setBaseDirectory(const QString &directory)
+{
+    m_document->setBaseDirectory(directory);
+}
+
 int DiffEditorController::contextLineCount() const
 {
     return m_document->contextLineCount();

src/plugins/diffeditor/diffeditorcontroller.h

@@ -48,6 +48,7 @@ public:
     bool isReloading() const;
 
     QString baseDirectory() const;
+    void setBaseDirectory(const QString &directory);
     int contextLineCount() const;
     bool ignoreWhitespace() const;
 

src/plugins/diffeditor/diffeditordocument.cpp

@@ -113,7 +113,8 @@ void DiffEditorDocument::setDiffFiles(const QList<FileData> &data, const QString
                                       const QString &startupFile)
 {
     m_diffFiles = data;
-    m_baseDirectory = directory;
+    if (!directory.isEmpty())
+        m_baseDirectory = directory;
     m_startupFile = startupFile;
     emit documentChanged();
 }
@@ -128,6 +129,11 @@ QString DiffEditorDocument::baseDirectory() const
     return m_baseDirectory;
 }
 
+void DiffEditorDocument::setBaseDirectory(const QString &directory)
+{
+    m_baseDirectory = directory;
+}
+
 QString DiffEditorDocument::startupFile() const
 {
     return m_startupFile;

src/plugins/diffeditor/diffeditordocument.h

@@ -60,6 +60,7 @@ public:
                       const QString &startupFile = QString());
     QList<FileData> diffFiles() const;
     QString baseDirectory() const;
+    void setBaseDirectory(const QString &directory);
     QString startupFile() const;
 
     void setDescription(const QString &description);

src/plugins/vcsbase/vcsbasediffeditorcontroller.cpp

@@ -236,6 +236,7 @@ VcsBaseDiffEditorController::VcsBaseDiffEditorController(IDocument *document,
     : DiffEditorController(document)
     , d(new VcsBaseDiffEditorControllerPrivate(this, client, workingDirectory))
 {
+    setBaseDirectory(workingDirectory);
 }
 
 VcsBaseDiffEditorController::~VcsBaseDiffEditorController()