Improve error reporting when a world fails to open

src/mcedit2/editorapp.py

@@ -709,7 +709,7 @@ class MCEditApp(QtGui.QApplication):
         except Exception as e:
             log.exception("EditorSession failed to open %s: %r", filename, e)
             errorTab = QtGui.QWidget()
-            setWidgetError(errorTab, e)
+            setWidgetError(errorTab, e, "An error occurred while opening %s" % filename)
             self.tabWidget.addTab(errorTab, "Failed to open %s" % filename)
 
         fileLoadingDialog.reset()

src/mcedit2/widgets/layout.py

@@ -1,4 +1,7 @@
 from __future__ import absolute_import, division, print_function, unicode_literals
+
+import traceback
+
 from PySide import QtGui
 from PySide.QtCore import Qt
 
@@ -45,7 +48,7 @@ def Column(*a, **kw):
         box.setContentsMargins(margin, margin, margin, margin)
     return box
 
-def setWidgetError(widget, exc):
+def setWidgetError(widget, exc, msg = "An error has occurred."):
     """
     Add a subwidget to `widget` that displays the error message for the exception `exc`
     :param widget:
@@ -53,6 +56,11 @@ def setWidgetError(widget, exc):
     :return:
     """
     layout = QtGui.QVBoxLayout()
-    layout.addWidget(QtGui.QLabel(exc.message))
-    layout.addStretch()
+    textArea = QtGui.QTextEdit()
+    textArea.setReadOnly(True)
+    message = msg + "\n"
+    message += str(exc) + "\n\n"
+    message += traceback.format_exc()
+    textArea.setText(message)
+    layout.addWidget(textArea)
     widget.setLayout(layout)

src/mcedit2/worldlist.py

@@ -353,8 +353,8 @@ class WorldListWidget(QtGui.QDialog, Ui_worldList):
             self.worldListModel = WorldListModel(worldFiles)
             self.worldListView.setModel(self.worldListModel)
 
-        except EnvironmentError as e:
-            setWidgetError(self, e)
+        except Exception as e:
+            setWidgetError(self, e, "An error occurred while scanning the saves folder.")
 
     def openWorldClicked(self):
         QtGui.qApp.chooseOpenWorld()
@@ -382,7 +382,7 @@ class WorldListWidget(QtGui.QDialog, Ui_worldList):
 
         except (EnvironmentError, LevelFormatError, zipfile.BadZipfile) as e:
             self.errorWidget = QtGui.QWidget()
-            setWidgetError(self.errorWidget, e)
+            setWidgetError(self.errorWidget, e, "An error occurred while reading the world %s." % filename)
             self.stackedWidget.addWidget(self.errorWidget)
             self.stackedWidget.setCurrentWidget(self.errorWidget)