Using Pinta-1.4-preview-20120908 on Windows XP I have been trying to test a bug 996490 and found out a crash which is a regression from previous development preview:
1. Open new image: 300 x 300
2. <Print screen> and paste with <CTRL>+V
3. Accept the "Expand canvas" button.
4. Click on "Undo" toolbar button.
5. File | Close and crash appears:
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Unhandled exception:
Exception has been thrown by the target of an invocation.
Details:
System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation. ---> System.NullReferenceException: Object reference not set to an instance of an object.
at Pinta.Core.ResizeHistoryItem.Dispose()
at Pinta.Core.CompoundHistoryItem.Dispose()
at Pinta.Core.DocumentWorkspaceHistory.<Clear>b__0(BaseHistoryItem item)
at System.Collections.Generic.List`1.ForEach(Action`1 action)
at Pinta.Core.DocumentWorkspaceHistory.Clear()
at Pinta.Core.Document.Close()
at Pinta.Core.WorkspaceManager.CloseDocument(Document document)
at Pinta.Actions.CloseDocumentAction.Activated(Object sender, EventArgs e)
--- End of inner exception stack trace ---
at System.RuntimeMethodHandle._InvokeMethodFast(IRuntimeMethodInfo method, Object target, Object[] arguments, SignatureStruct& sig, MethodAttributes methodAttributes, RuntimeType typeOwner)
at System.RuntimeMethodHandle.InvokeMethodFast(IRuntimeMethodInfo method, Object target, Object[] arguments, Signature sig, MethodAttributes methodAttributes, RuntimeType typeOwner)
at System.Reflection.RuntimeMethodInfo.Invoke(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture, Boolean skipVisibilityChecks)
at System.Delegate.DynamicInvokeImpl(Object[] args)
at GLib.Signal.ClosureInvokedCB(Object o, ClosureInvokedArgs args)
at GLib.SignalClosure.Invoke(ClosureInvokedArgs args)
at GLib.SignalClosure.MarshalCallback(IntPtr raw_closure, IntPtr return_val, UInt32 n_param_vals, IntPtr param_values, IntPtr invocation_hint, IntPtr marshal_data)
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According to the error message this is most probably related to this commit: https://github.com/PintaProject/Pinta/commit/9a999cf874eaa38ac29e598d4a2c630a3317918c
I have done some regression tests on Ubuntu 12.04 (checking out the one commit after another) and I have found out that first commit that this regression appears in is "Merge branch 'Magic-Wand-Tool' of https:/