Rename transient directory when saving document under new file

src/App/Document.cpp

@@ -459,8 +459,10 @@ void Document::onChanged(const Property* prop)
                     this->TransientDir.setValue(new_dir);
             }
         }
-        // make sure that the uuid is unique
-        else {
+        // when reloading an existing document the transient directory doesn't change
+        // so we must avoid to generate a new uuid
+        else if (TransDirNew.filePath() != TransDirOld.filePath()) {
+            // make sure that the uuid is unique
             std::string uuid = this->Uid.getValueStr();
             Base::Uuid id;
             Base::Console().Warning("Document with the UUID '%s' already exists, change to '%s'\n",
@@ -894,6 +896,7 @@ bool Document::saveAs(const char* file)
     if (this->FileName.getStrValue() != file) {
         this->FileName.setValue(file);
         this->Label.setValue(fi.fileNamePure());
+        this->Uid.touch(); // this forces a rename of the transient directory
     }
 
     return save();

src/App/PropertyFile.cpp

@@ -281,7 +281,6 @@ void PropertyFileIncluded::setPyObject(PyObject *value)
 
 void PropertyFileIncluded::Save (Base::Writer &writer) const
 {
-#if 0
     // when saving a document under a new file name the transient directory
     // name changes and thus the stored file name doesn't work any more.
     if (!_cValue.empty() && !Base::FileInfo(_cValue).exists()) {
@@ -289,7 +288,7 @@ void PropertyFileIncluded::Save (Base::Writer &writer) const
         if (fi.exists())
             _cValue = fi.filePath();
     }
-#endif
+
     if (writer.isForceXML()) {
         if (!_cValue.empty()) {
             Base::FileInfo file(_cValue.c_str());