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Fix mutable default argument in __deepcopy__ methods#186
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Mr-Neutr0n wants to merge 1 commit intosalesforce:mainfrom
Open
Fix mutable default argument in __deepcopy__ methods#186Mr-Neutr0n wants to merge 1 commit intosalesforce:mainfrom
Mr-Neutr0n wants to merge 1 commit intosalesforce:mainfrom
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Replace `memodict={}` with `memodict=None` and add a guard clause
to initialize to `{}` inside the method body. Mutable default
arguments are shared across all calls to the function, which can
lead to subtle bugs (see https://docs.python-guide.org/writing/gotchas/#mutable-default-arguments).
Affected files:
- merlion/utils/conj_priors.py
- merlion/post_process/base.py
- merlion/models/base.py (2 instances)
- merlion/models/layers.py
- merlion/models/ensemble/base.py
- merlion/models/ensemble/combine.py
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Summary
All
__deepcopy__methods across the codebase use a mutable default argument (memodict={}). Mutable defaults are shared across all calls to the function, which is a well-known Python gotcha that can lead to subtle, hard-to-debug issues.This PR replaces
memodict={}withmemodict=Noneand adds a guard clause (if memodict is None: memodict = {}) inside each method body.Changes
Fixed 7 instances across 6 files:
merlion/utils/conj_priors.py—ConjPrior.__deepcopy__merlion/post_process/base.py—PostRuleBase.__deepcopy__merlion/models/base.py—Config.__deepcopy__andModelBase.__deepcopy__merlion/models/layers.py—LayeredModelConfig.__deepcopy__merlion/models/ensemble/base.py—EnsembleConfig.__deepcopy__merlion/models/ensemble/combine.py—CombinerBase.__deepcopy__Test plan
pytest/ CI)