Fixes thread-safety issue in Message.types() #151
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ameyer-rigetti
commented
Apr 16, 2021
| @@ -120,13 +120,12 @@ def types(): | |||
| :return: A dictionary of ``Message`` types. | |||
| :rtype: Dict[str,type] | |||
| """ | |||
| if Message._types is None: | |||
| Message._types = {} | |||
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One thread might execute this while another thread is in the middle of building the dictionary. The dictionary is a class member and eventually contains a union of all message types encountered, so this fix should cause no backwards incompatibilities.
notmgsk
approved these changes
Apr 19, 2021
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Multiple threads can sometimes collide when building
Message._types. This addresses that by ensuring the dictionary is never reset as a whole.