While looking into https://github.com/astral-sh/ruff/issues/13545 I
noticed that we return `None` here if you pass a block of comments. This
is annoying because it causes `adjust_indentation` to fall back to
LibCST which panics when it cannot find a statement.
## Summary
It turns out we saw a panic in cases when dedenting blocks like the `def
wrapper` here:
```python
def instrument_url(f: UrlFuncT) -> UrlFuncT:
# TODO: Type this with ParamSpec to preserve the function signature.
if not INSTRUMENTING: # nocoverage -- option is always enabled; should we remove?
return f
else:
def wrapper(
self: "ZulipTestCase", url: str, info: object = {}, **kwargs: Union[bool, str]
) -> HttpResponseBase:
```
Since we relied on the first line to determine the indentation, instead
of the first non-empty line.
## Test Plan
`cargo test`
## Summary
Often, when fixing, we need to dedent a block of code (e.g., if we
remove an `if` and dedent its body). Today, we use LibCST to parse and
adjust the indentation, which is really expensive -- but this is only
really necessary if the block contains a multiline string, since naively
adjusting the indentation for such a string can change the whitespace
_within_ the string.
This PR uses a simple dedent implementation for cases in which the block
doesn't intersect with a multi-line string (or an f-string, since we
don't support tracking multi-line strings for f-strings right now).
We could improve this even further by using the ranges to guide the
dedent function, such that we don't apply the dedent if the line starts
within a multiline string. But that would also need to take f-strings
into account, which is a little tricky.
## Test Plan
`cargo test`
Update to [Rust
1.74](https://blog.rust-lang.org/2023/11/16/Rust-1.74.0.html) and use
the new clippy lints table.
The update itself introduced a new clippy lint about superfluous hashes
in raw strings, which got removed.
I moved our lint config from `rustflags` to the newly stabilized
[workspace.lints](https://doc.rust-lang.org/stable/cargo/reference/workspaces.html#the-lints-table).
One consequence is that we have to `unsafe_code = "warn"` instead of
"forbid" because the latter now actually bans unsafe code:
```
error[E0453]: allow(unsafe_code) incompatible with previous forbid
--> crates/ruff_source_file/src/newlines.rs:62:17
|
62 | #[allow(unsafe_code)]
| ^^^^^^^^^^^ overruled by previous forbid
|
= note: `forbid` lint level was set on command line
```
---------
Co-authored-by: Charlie Marsh <charlie.r.marsh@gmail.com>