fix/19447-forward-references - Branch - PrefectHQ/prefect

fix: defer forward reference resolution in ValidatedFunction

#19452

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fix/19447-forward-references

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680f8e7

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bench_flow_decorator

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fix: defer forward reference resolution in ValidatedFunction closes #19447 When using `from __future__ import annotations`, the `@flow` decorator was failing if a forward-referenced Pydantic model was defined after the function using it. The issue occurred because ValidatedFunction tried to resolve forward references at decoration time by calling `model_rebuild()`, but the referenced types didn't exist in the function's `__globals__` yet. This fix: - Tracks deferred rebuilds with `_needs_rebuild` flag to avoid performance overhead - Only calls `model_rebuild()` once during first validation if needed - Catches NameError/AttributeError during initial model_rebuild attempt - Extended test coverage to ensure no rebuilds happen when not needed 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude <noreply@anthropic.com>

680f8e7

2 days ago

by zzstoatzz

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