Fix StopIteration exception during scope analysis #298
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During scope analysis all attribute accesses are collected for matching on import names. The matching code (specifically `_gen_dotted_names`) was not prepared for all types of expressions. In particular, complex expressions like `foo[0].bar.baz()` caused a `StopIteration` exception when `_gen_dotted_names` calls itself recursively. The nested call doesn't yield any values, and so calling `next()` on it raises. This commit fixes these types of errors.
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jimmylai
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May 21, 2020
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| next_pair = next(name_values, None) | ||
| if next_pair is None: | ||
| return |
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Can we just add try ... except StopIteration? That can be more efficient and probably easier to understand.
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Hmm, sure. Why is it more efficient?
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That way we saved one extra next call.
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Then I don't understand your suggestion :)
Apart from the way it's currently written, I can imagine this:
try:
(next_name, next_node) = next(name_values)
yield (f"...", ...)
...
except StopIteration:
return
which is the same amount of next calls
jimmylai
approved these changes
May 21, 2020
|
I haven't yet. |
jimmylai
reviewed
May 21, 2020
| next_pair = next(name_values, None) | ||
| if next_pair is None: | ||
| return | ||
| (next_name, next_node) = next_pair |
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We just need try catch on this line. Then we can save the next in next_pair = next(name_values, None).
|
Merge this for now and will submit the proposed change in another PR. |
This was referenced May 27, 2020
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Summary
During scope analysis all attribute accesses are collected for matching on
import names. The matching code (specifically
_gen_dotted_names) was notprepared for all types of expressions. In particular, complex expressions like
foo[0].bar.baz()caused aStopIterationexception when_gen_dotted_namescalls itself recursively. The nested call doesn't yield any values, and so
calling
next()on it raises.This commit fixes these types of errors.
Test Plan
Added test case