Astroid 2.0.1 regression: Not detecting that Exception self.args is iterable

[kayhayen]

Steps to reproduce

nuitka/Errors.py:37 E1133 not-an-iterable NuitkaNodeError.str
Non-iterable value self.args is used in an iterating context

This is self.args from Exception, as can be seen in the code here:

class NuitkaErrorBase(Exception):
    pass


class NuitkaNodeError(NuitkaErrorBase):

    # Try to output more information about nodes passed.
    def __str__(self):
        from nuitka.codegen.Indentation import indented

        parts = [""]

        for arg in self.args:
            if hasattr(arg, "asXmlText"):
                parts.append(indented("\n%s\n" % arg.asXmlText()))
            else:
                parts.append(arg)

        parts.append("")
        parts.append("The above information should be included in a
bug report.")

I am assuming that the other code in apart from iteration of "self.args" in str is not relevant, but I did not try.

Current behavior

Warning is given:
nuitka/Errors.py:37 E1133 not-an-iterable NuitkaNodeError.str
Non-iterable value self.args is used in an iterating context

Expected behavior

The 2.0.0 version of Astroid doesn't give such warnings, the update to 2.0.1 does.

pylint --version output

python3.6 -m pylint --version
main.py 2.0.0
astroid 2.0.1
Python 3.6.3 (default, Mar 27 2018, 00:29:24)
[GCC 6.3.0 20170516]

Note: Didn't happen with 2.0.0.dev4

[ghost]

Reproducible with Eclipse PyDev + PyLint.

C:\>python -m pylint --version
__main__.py 2.1.1
astroid 2.0.4
Python 3.7.0 (v3.7.0:1bf9cc5093, Jun 27 2018, 04:59:51) [MSC v.1914 64 bit (AMD64)]

Minimal example:

class MyException(Exception):
    def foobar(self):
        for arg in self.args:
            print(arg)

[mthuurne]

Although the commit that should fix this issue exists on the Astroid 2.3.x branches, the issue still occurs for me with Astroid 2.3.2:

$ pylint --version
pylint 2.4.3
astroid 2.3.2
Python 3.7.2 (default, Feb 26 2019, 13:02:33) 
[GCC 7.3.1 20180323 [gcc-7-branch revision 258812]]

[PCManticore]

Thanks for checking @mthuurne I can reproduce it as well.