inconsistent-return-statements not working in try branches

[joshuahaertel]

Steps to reproduce

Add a return in the try clause

def foo(bar):
    try:
        return bar.baz
    except AttributeError:
        pass

Current behavior

Pylint emits no warning for inconsistent-return-statements. Note that it will emit a warning if the value is returned in the except clause.

Expected behavior

Pylint should emit a warning for not explicitly returning a value if an exception is hit, be it in the except clause itself or at the end of the call.

pylint --version output

$ pylint --version output
pylint 2.4.4
astroid 2.3.3
Python 3.6.7 (default, Oct 22 2018, 11:32:17) 
[GCC 8.2.0]

[joshuahaertel]

Also worth noting that returning in some except clauses and not in others does not emit a warning either.

def foo(bar):
    try:
        return bar.baz
    except AttributeError:
        pass
    except KeyError:
        return True

[PCManticore]

Does the error reproduce for you for these two examples or is there additional code that's needed for reproduction? Also tested with the unreleased 2.5.0 from the master branch and can't reproduce it there as well.

Actually I'm dumb, I misinterpreted what the issue was about, the error should be emitted.

[same-id]

I think this now introduces a different bug

try:
  n = int(s)
  if n < 1:
    raise ValueError()
  return n
except ValueError:
  parser.error('parser error') # calls system exit

even if I replace parser.error() with an explicit function that is marked with -> typing.NoReturn as suggested in #4122 is still a false positive.

The only solution now is to preinitialize:

n = None
try:
  n = int(s)
  if n < 1:
    raise ValueError()
except ValueError:
  parser.error('parser error') # calls system exit
return n

Which isn't that great since it requires moving n to a less confined scope

[hippo91]

@same-id thanks for the report. I can reproduce. Can you open a new issue for this please?

[hippo91]

By the way another solution seems to add a return statement just before the parser.error call.

[hippo91]

@same-id i opened #4188

[same-id]

Thanks!