Multiple removeCallback calls in pymel

[cruz1n]

Pymel will call removeCallback for already-loaded plugins if the plugins are loaded again. This occurs here: https://github.com/LumaPictures/pymel/blob/master/pymel/core/__init__.py#L247

If a callback is removed via this code path, the internal callback cache is not updated to reflect this, which can result in a redundant removeCallback call here: https://github.com/LumaPictures/pymel/blob/master/pymel/core/__init__.py#L213

The workaround is to add the following code after removing the callback at line 247: _pluginData[pluginName]['callbackId'] = None

[jamesdeschenes]

Just to add some extra context - I believe the line numbers in the above links refer to the following commit as the line numbers have changed since the issue was opened.

pymel/pymel/core/__init__.py

Line 247 in 685a142

api.MEventMessage.removeCallback(id)

pymel/pymel/core/__init__.py

Line 213 in 685a142

api.MEventMessage.removeCallback(_pluginData[pluginName]['callbackId'])