fix save warning crash on new document and change save warning dialog icon

csgui/messageBox.py

@@ -8,7 +8,7 @@ class UnsavedMessageBox(QMessageBox):
     def __init__(self, fileName):
         super().__init__()
 
-        self.setIcon(QMessageBox.Question)
+        self.setIcon(QMessageBox.Information)
         self.setWindowTitle("Unsaved changes")
         self.setText(f"The document \"{fileName}\" has been modified.")
         self.setInformativeText("Do you want to save your changes?")

gui.py

@@ -1059,7 +1059,12 @@ class DocumentWindow(QMdiSubWindow):
         if self.lastHash == self.doc.getHash():
             return True
         else:
-            wantToSave = UnsavedMessageBox(os.path.basename(self.currentFilePath)).exec()
+            if self.currentFilePath:
+                fileName = os.path.basename(self.currentFilePath)
+            else:
+                fileName = "Unsaved"
+                
+            wantToSave = UnsavedMessageBox(fileName).exec()
 
             if wantToSave == QMessageBox.Save:
                 if not self.currentFilePath: