binding: treat assert False as terminating control flow
#603
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This change makes Pyrefly recognize `assert False` as a control flow terminator, similar to `raise`. It adds a call to `mark_flow_termination` when the assert condition is statically known to be `False`.
yangdanny97
requested changes
Jun 30, 2025
| x = 10 | ||
| assert False, "This assertion should cause control flow to terminate in this branch." | ||
| # This line should be unreachable. | ||
| raise Exception("Something unexpected happened here!") |
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I don't understand how this test demonstrates the difference the code change makes.
I would suggest marking the test function to return something like int, and seeing if Pyrefly complains about implicit None return.
For example, here:
With your code change, the error in the second function will not be there.
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I've patched the test and added handling in another place that was missed
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@yangdanny97 has imported this pull request. If you are a Meta employee, you can view this in D78165436. |
stroxler
approved these changes
Jul 11, 2025
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@yangdanny97 merged this pull request in c83d376. |
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This change makes Pyrefly recognize
assert Falseas a control flow terminator, similar toraise. It adds a call tomark_flow_terminationwhen the assert condition is statically known to beFalse.closes #599