Retire astor, as ast.unparse exists, and migrate it into API-compatible shims of ast for older versions of python

[KOLANICH]

No description provided.

[SamuelMarks]

Yep I've been doing that for ages: https://github.com/offscale/cdd-python/blob/f64f886/cdd/source_transformer.py#L13-L27

[Kodiologist]

Hy also does this, since hylang/hy#1999. astor might as well do it internally.

[leycec]

Necrobump. The astor.code_to_ast() function decompiling arbitrary code objects into corresponding ASTs still appears to have no equivalent in any other library – including the standard ast module. Is that correct? If so, astor should absolutely not retire but instead mono-focus on this one thing astor still does that nobody else does.

In fact, that's exactly how I discovered astor: via this StackOverflow question, whose first comment namedrops astor as the only available solution. Long live astor! ✊

[akaihola]

Annoyingly, ast.unparse() outputs single quoted strings by default while modern code reformatters default to double quotes.

ast.unparse() behavior is impossible to change since it:

• doesn't provide any options to tweak its behavior
• uses the ast._Unparser class which is not part of the public API

ikamensh/flynt#195 is currently struggling with this and would benefit from astor continuing to be maintained and made compatible with Python 3.14.

[Kodiologist]

modern code reformatters default to double quotes

That seems like an unforced error. If I recall correctly, Python's repr has always used single quotes, and single quotes have always predominated in official documentation. I'm not sure why Black decided to go with double quotes.

[akaihola]

Another difference in behavior between astor and ast.unparse():

>>> import ast
>>> import astor
>>> node = ast.JoinedStr(
...     values=[ast.FormattedValue(value=ast.IfExp(test=ast.Name(id='c'), body=ast.Name(id='a'), orelse=ast.Name(id='b')), conversion=-1)]
... )
>>> print(ast.unparse(node))
f'{(a if c else b)}'
>>> print(astor.to_source(node))
f"""{a if c else b}"""

This is being discussed in ikamensh/flynt#205, preventing migrating from astor to ast.unparse().