fix(handlers): do not evaluate handler annotations in inspect.signature on Python 3.14 - #3204
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…re on Python 3.14 Since PEP 649 (Python 3.14), annotations are lazily evaluated and inspect.signature() resolves them eagerly by default. Event listeners and locator handlers annotated with names that only exist under `if TYPE_CHECKING:` therefore raised NameError when the signature was inspected, even though only the parameter list is needed. Ask for unresolved forward references instead. Fixes: microsoft/playwright#42857
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The fix itself looks good. The tests fail the lint job, though: mypy and pyright reject the |
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Since both call sites are in shared _impl code, the sync mirrors don't add coverage. Let's drop the two tests/sync/ additions and keep just the async console and locator-handler tests.
…ions Replace the Unresolvable placeholder with the real handler types imported under `if TYPE_CHECKING:` and aliased, e.g. ConsoleMessage as TypeCheckingOnlyConsoleMessage. The alias stays undefined at runtime (still exercising PEP 649 lazy annotations) while mypy and pyright accept the handler signatures.
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Done — replaced the placeholder with TYPE_CHECKING-only aliases of the real types ( |
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Summary
inspect.signature()evaluates the lazily-computed annotations (PEP 649/749) by default, so event listeners and locator handlers annotated with names that only exist underif TYPE_CHECKING:raisedNameErrorwhen Playwright inspected the handler signature — even though only the parameter list is used.signature()compat helper that passesannotation_format=Format.FORWARDREFon Python 3.14+ and is a plaininspect.signature()on older versions, and use it at the two call sites (wrap_handler,LocatorHandler.__call__).Fixes microsoft/playwright#42857