Syntax Error in generated code

[phiresky]

• cattrs version: current master
• Python version: 3.10
• Operating System: Linux

The error

 File ".venv/lib/python3.10/site-packages/cattrs/dispatch.py", line 122, in dispatch                                                
   return handler(typ)                                                                                                                                       
 File ".venv/lib/python3.10/site-packages/cattrs/converters.py", line 829, in gen_structure_mapping                                      
   h = make_mapping_structure_fn(                                                                                                                                         
 File ".venv/lib/python3.10/site-packages/cattrs/gen.py", line 726, in make_mapping_structure_fn
   eval(compile(script, "", "exec"), globs)                                                                                                                                
 File "<string>", line 17                                                                                                                                                 
   raise IterableValidationError('While structuring dict[typing.Union[typing.Literal['ca', 'pro', 'fa', 'car', 'ing_emb'], typing.Literal['wgr', 'cwg', 'fcc', 'wcc']], statistics.FrequenciesInfo]', errors, __cattr_mapping_cl)

    | SyntaxError: invalid syntax. Perhaps you forgot a comma?                                                                                                                 

The offending code is here gen :

It seems to generate code that assumes that the repr of the offending type does not include '. ' is not escaped.

[Tinche]

Thanks, I'm aware of this (there's another, similar issue), it's on my radar for the next version. Just out of curiosity, if you change the line to

    raise IterableValidatoinError("While structuring {cl!r}", errors, __cattr_mapping_cl)

i.e. single quotes to double quotes, does it fix it?

[phiresky]

Yes, that does seem to fix it. Though I'm not sure if I would trust all types to not contain a " either.

[Tinche]

Yeah, the play might be to just escape any single quotes in the repr.

[Tinche]

@phiresky this should be fixed on main, can you verify before I release the next version?

[phiresky]

Thanks for fixing it! Sorry, it might take a while before I get back to the code that for me generates this error, so probably you shouldn't wait for me.

[phiresky]

Seems to work, though I'm getting a .venv/lib/python3.10/site-packages/cattrs/converters.py:541: error: Invalid "type: ignore" comment mypy error on master

[Tinche]

Confirmed. Will test on 3.7 too before removing the comment.

[Tinche]

I fixed it by removing the comment, seems to work fine. Give it one more test for me? <3

[aarnphm]

I'm I thought that mypy also accept # type: ignore syntax 🤔

[Tinche]

It does. It can be configured to not take it though, which I think is happening (at least for me, I have that option set up).

[aarnphm]

got it. I think I also configure it to accept the syntax on pyright end. Removing it makes sense then.