Python syntax checkers that test edge cases

Question

Are there syntax checkers able to detect broken code based on edge cases. An example:

def run():
    for j in [0, 1]:
        if j == 0:
            yield j
        else:
            yield None


for i in run():
    print i * 2

This code is broken because None * 2 does not make sense. Are there tools to detect this kind of error ?

Thank you

Line 10: TypeError: unsupported operand type(s) for *: 'NoneType' and 'int' — Chris
– Chris, Commented Oct 12, 2016 at 22:56
This is not a syntax error; this is a run-time semantic error. — Prune
– Prune, Commented Oct 12, 2016 at 22:57
No, your code is syntactically correct so no syntax checker can detect any problems in it. — Stop harming Monica
– Stop harming Monica, Commented Oct 12, 2016 at 22:57

Patrick Haugh · Accepted Answer · 2016-10-12 23:05:14Z

3

You're looking for a type checker, not a syntax checker. Here's one attempt to make one: http://mypy-lang.org/

answered Oct 12, 2016 at 23:05

Patrick Haugh

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Comments

Artem Sychov · Accepted Answer · 2016-10-12 23:55:01Z

1

You need a type checker, not a syntax checker. github.com/python/mypy

answered Oct 12, 2016 at 23:55

Artem Sychov

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