Overwriting __repr__ for str subclasses results in ValueError: malformed node or string raised within the ast module

[tyralla]

Description of the problem

Weird output in the internal console when trying to overwrite the special method __repr__ for subclasses of str.

Minimal test case

For reproducing the problem, the following test class should be sufficient:

class Test(str):
    def __repr__(self):
        return 'something'

Writing...

Test()

...returns (as expected):

something

But when I write...

test = Test()

...the following error message is returned:

raise ValueError('malformed node or string: ' + repr(node))
ValueError: malformed node or string: <_ast.Name object at 0x000000005FD5B550>

So far, I could reproduce this problem only when using the IPython console in Spyder.

Versions and main components

• Spyder Version: 3.2.3
• Python Version: 3.6.3
• Qt Version: 5.6.2
• PyQt Version: 5.6.0
• Operating system: Windows

Dependencies

IPython >=4.0 : 6.1.0 (OK)
cython >=0.21 : 0.25.2 (OK)
jedi >=0.9.0 : 0.10.2 (OK)
nbconvert >=4.0 : 5.1.1 (OK)
numpy >=1.7 : 1.13.3 (OK)
pandas >=0.13.1 : 0.20.1 (OK)
pycodestyle >=2.3: 2.3.1 (OK)
pyflakes >=0.6.0 : 1.5.0 (OK)
pygments >=2.0 : 2.2.0 (OK)
pylint >=0.25 : 1.6.4 (OK)
qtconsole >=4.2.0: 4.3.1 (OK)
rope >=0.9.4 : 0.9.4-1 (OK)
sphinx >=0.6.6 : 1.5.1 (OK)
sympy >=0.7.3 : 1.0 (OK)

[dalthviz]

Thanks for reporting @tyralla. I think this is related with #5636, PR #5746 implements a fix. Would you like to help us testing the PR I mention to see if that fixes this issue?

[ccordoba12]

Closing as a duplicate of issue #5636. Feel free to keep posting about this on PR #5746.