(This is not possible to actually use until
https://github.com/astral-sh/ruff/pull/8854 is merged.)
This commit slots in support for formatting Markdown fenced code
blocks[1]. With the refactoring done for reStructuredText previously,
this ended up being pretty easy to add. Markdown code blocks are also
quite a bit easier to parse and recognize correctly.
One point of contention in #8860 is whether to assume that unlabeled
Markdown code fences are Python or not by default. In this PR, we make
such an assumption. This follows what `rustdoc` does. The mitigation
here is that if an unlabeled code block isn't Python, then it probably
won't parse as Python. And we'll end up skipping it. So in the vast
majority of cases, the worst thing that can happen is a little bit of
wasted work.
Closes#8860
[1]: https://spec.commonmark.org/0.30/#fenced-code-blocks
(This is not possible to actually use until
https://github.com/astral-sh/ruff/pull/8854 is merged.)
ruff_python_formatter: add reStructuredText docstring formatting support
This commit makes use of the refactoring done in prior commits to slot
in reStructuredText support. Essentially, we add a new type of code
example and look for *both* literal blocks and code block directives.
Literal blocks are treated as Python by default because it seems to be a
[common
practice](https://github.com/adamchainz/blacken-docs/issues/195).
That is, literal blocks like this:
```
def example():
"""
Here's an example::
foo( 1 )
All done.
"""
pass
```
Will get reformatted. And code blocks (via reStructuredText directives)
will also get reformatted:
```
def example():
"""
Here's an example:
.. code-block:: python
foo( 1 )
All done.
"""
pass
```
When looking for a code block, it is possible for it to become invalid.
In which case, we back out of looking for a code example and print the
lines out as they are. As with doctest formatting, if reformatting the
code would result in invalid Python or if the code collected from the
block is invalid, then formatting is also skipped.
A number of tests have been added to check both the formatting and
resetting behavior. Mixed indentation is also tested a fair bit, since
one of my initial attempts at dealing with mixed indentation ended up
not working.
I recommend working through this PR commit-by-commit. There is in
particular a somewhat gnarly refactoring before reST support is added.
Closes#8859
In the source of working on #8859, I made a number of smallish refactors
to how code snippet formatting works. Most or all of these were
motivated by writing in support for reStructuredText blocks. They have
some fundamentally different requirements than doctests, and there are a
lot more ways for reStructuredText blocks to become invalid.
(Commit-by-commit review is recommended as the commit messages provide
further context on each change. I split this off from ongoing work to
make review more manageable.)
This turns `string` into a parent module with a `docstring` sub-module.
I arranged things this way because there are parts of the `string`
module that the `docstring` module wants to know about (such as a
`NormalizedString`). The alternative I think would be to make
`docstring` a sibling module and expose more of `string`'s internals.
I think I overall like this change because it gives docstring handling a
bit more room to breath. It has grown quite a bit with the addition of
code snippet formatting.
[This was suggested by
@charliermarsh.](https://github.com/astral-sh/ruff/pull/8811#discussion_r1401169531)
