fix(ast_utils): use None sentinel for walk_type_tree seen parameter#165
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SoundMatt wants to merge 1 commit into
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fix(ast_utils): use None sentinel for walk_type_tree seen parameter#165SoundMatt wants to merge 1 commit into
SoundMatt wants to merge 1 commit into
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Using a mutable dict as a default argument (`seen={}`) is a classic
Python gotcha: the dict is created once at function-definition time and
shared across all calls. After the first call the dict retains every
visited type name, so a second call would immediately short-circuit on
every node and do nothing.
Replace with the standard `seen=None` sentinel pattern and initialise
`seen = {}` inside the function body.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Signed-off-by: Matt Jones <47545907+SoundMatt@users.noreply.github.com>
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walk_type_treedeclaresseen={}as a default argument. Python evaluates default argument values once at function-definition time, so every call that omitsseenshares the same dict object. After the first call the dict already contains all visited type names, meaning every subsequent call skips every node and does nothing.Fix with the standard sentinel pattern:
seen=None, initialised to{}inside the function body.