#1773 Accessing certain pane properties crashes SciTE

[felix]

Executing any of the following lines of Lua crashes SciTE.

print(editor.DirectFunction)
print(editor.DirectPointer)
print(editor.DocPointer)
print(editor.CharacterPointer)

[Neil Hodgson]

They show an error message and terminate SciTE since these functions should not be called by the part of the interface code to Scintilla which is used by scripts. The error message is shown on Windows but doesn't currently appear on GTK+ which doesn't handle fatal panics well.

[felix]

If they should not be called, why are they exposed at all?! Why couldn't these accesses just return nil instead of crashing loudly? Even an error box is wrong here; it's supposed to be a programmatic interface. Doing the equivalent of

for key, value in pairs(editor) do
    print(key, value)
end

(which I had to monkeypatch in anyway) should neither crash nor inconvenience the user in any way.

[Neil Hodgson]

They are exposed by some generic code that doesn't understand that the call it uses is dropping bits from (64-bit when on 64-bit platforms) pointers returned through a 32-bit interface.

If its important to you then handle the ScintillaFailure exception in the scripting layer.

[Neil Hodgson]

Fix committed as [516078].