language-servers/ruff
1
0
Fork 0
mirror of https://github.com/astral-sh/ruff.git synced 2025-09-28 21:05:08 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 1

Preserve newlines after nested compound statements (#7608)

Browse source 
## Summary

Given:
```python
if True:
    if True:
        pass
    else:
        pass
        # a

        # b
        # c

else:
    pass
```

We want to preserve the newline after the `# c` (before the `else`).
However, the `last_node` ends at the `pass`, and the comments are
trailing comments on the `pass`, not trailing comments on the
`last_node` (the `if`). As such, when counting the trailing newlines on
the outer `if`, we abort as soon as we see the comment (`# a`).

This PR changes the logic to skip _all_ comments (even those with
newlines between them). This is safe as we know that there are no
"leading" comments on the `else`, so there's no risk of skipping those
accidentally.

Closes https://github.com/astral-sh/ruff/issues/7602.

## Test Plan

No change in compatibility.

Before:

| project | similarity index | total files | changed files |

|--------------|------------------:|------------------:|------------------:|
| cpython | 0.76083 | 1789 | 1631 |
| django | 0.99983 | 2760 | 36 |
| transformers | 0.99963 | 2587 | 319 |
| twine | 1.00000 | 33 | 0 |
| typeshed | 0.99979 | 3496 | 22 |
| warehouse | 0.99967 | 648 | 15 |
| zulip | 0.99972 | 1437 | 21 |

After:

| project | similarity index | total files | changed files |

|--------------|------------------:|------------------:|------------------:|
| cpython | 0.76083 | 1789 | 1631 |
| django | 0.99983 | 2760 | 36 |
| transformers | 0.99963 | 2587 | 319 |
| twine | 1.00000 | 33 | 0 |
| typeshed | 0.99983 | 3496 | 18 |
| warehouse | 0.99967 | 648 | 15 |
| zulip | 0.99972 | 1437 | 21 |
This commit is contained in:
Charlie Marsh 2023-09-25 10:21:44 -04:00 • committed by GitHub
parent 8ce138760a
commit 17ceb5dcb3
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
8 changed files with 182 additions and 42 deletions
Download patch file Download diff file Expand all files Collapse all files

38
crates/ruff_python_formatter/src/comments/format.rs
View file

@ -3,7 +3,7 @@ use std::borrow::Cow;
use ruff_formatter::{format_args, write, FormatError, FormatOptions, SourceCode};
use ruff_python_ast::node::{AnyNodeRef, AstNode};
use ruff_python_ast::PySourceType;
use ruff_python_trivia::{lines_after, lines_before};
use ruff_python_trivia::{lines_after, lines_after_ignoring_trivia, lines_before};
use ruff_text_size::{Ranged, TextLen, TextRange};
use crate::comments::{CommentLinePosition, SourceComment};
@ -96,16 +96,32 @@ impl Format<PyFormatContext<'_>> for FormatLeadingAlternateBranchComments<'_> {
write!(f, [leading_comments(self.comments)])?;
} else if let Some(last_preceding) = self.last_node {
// The leading comments formatting ensures that it preserves the right amount of lines after
// We need to take care of this ourselves, if there's no leading `else` comment.
let end = if let Some(last_trailing) =
f.context().comments().trailing(last_preceding).last()
{
last_trailing.end()
} else {
last_preceding.end()
};
write!(f, [empty_lines(lines_after(end, f.context().source()))])?;
// The leading comments formatting ensures that it preserves the right amount of lines
// after We need to take care of this ourselves, if there's no leading `else` comment.
// Since the `last_node` could be a compound node, we need to skip _all_ trivia.
//
// For example, here, when formatting the `if` statement, the `last_node` (the `while`)
// would end at the end of `pass`, but we want to skip _all_ comments:
// ```python
// if True:
// while True:
// pass
// # comment
//
// # comment
// else:
// ...
// ```
//
// `lines_after_ignoring_trivia` is safe here, as we _know_ that the `else` doesn't
// have any leading comments.
write!(
f,
[empty_lines(lines_after_ignoring_trivia(
last_preceding.end(),
f.context().source()
))]
)?;
}
Ok(())