Rule described here: https://www.flake8rules.com/rules/E101.html
I tried to follow contributing guidelines closely, I've never worked with Rust before. Stumbled across Ruff a few days ago and would like to use it in our project, but we use a bunch of flake8 rules that are not yet implemented in ruff, so I decided to give it a go.
Following up on #2018/#2019 discussion, this moves the readme's development-related bits to `CONTRIBUTING.md` to avoid duplication, and fixes up the commands accordingly 😄
As per Cargo.toml our minimal supported Rust version is 1.65.0, so we
should be using that version in our CI for cargo test and cargo build.
This was apparently accidentally changed in
79ca66ace5.
As we surface rule names more to users we want
them to be easier to type than PascalCase.
Prior art:
Pylint and ESLint also use kebab-case for their rule names.
Clippy uses snake_case but only for syntactical reasons
(so that the argument to e.g. #![allow(clippy::some_lint)]
can be parsed as a path[1]).
[1]: https://doc.rust-lang.org/reference/paths.html
This PR adds a new check that turns expressions such as `[1, 2, 3] + foo` into `[1, 2, 3, *foo]`, since the latter is easier to read and faster:
```
~ $ python3.11 -m timeit -s 'b = [6, 5, 4]' '[1, 2, 3] + b'
5000000 loops, best of 5: 81.4 nsec per loop
~ $ python3.11 -m timeit -s 'b = [6, 5, 4]' '[1, 2, 3, *b]'
5000000 loops, best of 5: 66.2 nsec per loop
```
However there's a couple of gotchas:
* This felt like a `simplify` rule, so I borrowed an unused `SIM` code even if the upstream `flake8-simplify` doesn't do this transform. If it should be assigned some other code, let me know 😄
* **More importantly** this transform could be unsafe if the other operand of the `+` operation has overridden `__add__` to do something else. What's the `ruff` policy around potentially unsafe operations? (I think some of the suggestions other ported rules give could be semantically different from the original code, but I'm not sure.)
* I'm not a very established Rustacean, so there's no doubt my code isn't quite idiomatic. (For instance, is there a neater way to write that four-way `match` statement?)
Thanks for `ruff`, by the way! :)
# This commit has been generated via the following Python script:
# (followed by `cargo +nightly fmt` and `cargo dev generate-all`)
# For the reasoning see the previous commit(s).
import re
import sys
for path in (
'src/violations.rs',
'src/rules/flake8_tidy_imports/banned_api.rs',
'src/rules/flake8_tidy_imports/relative_imports.rs',
):
with open(path) as f:
text = ''
while line := next(f, None):
if line.strip() != 'fn message(&self) -> String {':
text += line
continue
text += ' #[derive_message_formats]\n' + line
body = next(f)
while (line := next(f)) != ' }\n':
body += line
# body = re.sub(r'(?<!code\| |\.push\()format!', 'format!', body)
body = re.sub(
r'("[^"]+")\s*\.to_string\(\)', r'format!(\1)', body, re.DOTALL
)
body = re.sub(
r'(r#".+?"#)\s*\.to_string\(\)', r'format!(\1)', body, re.DOTALL
)
text += body + ' }\n'
while (line := next(f)).strip() != 'fn placeholder() -> Self {':
text += line
while (line := next(f)) != ' }\n':
pass
with open(path, 'w') as f:
f.write(text)
Fixes: #1953
@charliermarsh thank you for the tips in the issue.
I'm not very familiar with Rust, so please excuse if my string formatting syntax is messy.
In terms of testing, I compared output of `flake8 --format=pylint ` and `cargo run --format=pylint` on the same code and the output syntax seems to check out.
This is slightly buggy due to Instagram/LibCST#855; it will complain `[ERROR] Failed to fix nested with: Failed to extract CST from source` when trying to fix nested parenthesized `with` statements lacking trailing commas. But presumably people who write parenthesized `with` statements already knew that they don’t need to nest them.
Signed-off-by: Anders Kaseorg <andersk@mit.edu>
I accept any suggestion. By the way, I have a doubt, I have checked and all flake8-pie plugins can be fixed by ruff, but is it necessary that this one is also fixed automatically ?
rel #1543
The idea is to follow the Rust naming convention for lints[1]:
> the lint name should make sense when read as
> "allow lint-name" or "allow lint-name items"
Following that convention prefixing "Banned" is
redundant as it could be prefixed to any lint name.
[1]: https://rust-lang.github.io/rfcs/0344-conventions-galore.html#lints
Implements [flake8-commas](https://github.com/PyCQA/flake8-commas). Fixes#1058.
The plugin is mostly redundant with Black (and also deprecated upstream), but very useful for projects which can't/won't use an auto-formatter.
This linter works on tokens. Before porting to Rust, I cleaned up the Python code ([link](https://gist.github.com/bluetech/7c5dcbdec4a73dd5a74d4bc09c72b8b9)) and made sure the tests pass. In the Rust version I tried to add explanatory comments, to the best of my understanding of the original logic.
Some changes I did make:
- Got rid of rule C814 - "missing trailing comma in Python 2". Ruff doesn't support Python 2.
- Merged rules C815 - "missing trailing comma in Python 3.5+" and C816 - "missing trailing comma in Python 3.6+" into C812 - "missing trailing comma". These Python versions are outdated, didn't think it was worth the complication.
- Added autofixes for C812 and C819.
Autofix is missing for C818 - "trailing comma on bare tuple prohibited". It needs to turn e.g. `x = 1,` into `x = (1, )`, it's a bit difficult to do with tokens only, so I skipped it for now.
I ran the rules on cpython/Lib and on a big internal code base and it works as intended (though I only sampled the diffs).
This makes it easier to see which rules you're enabling when selecting
one of the pylint codes (like `PLC`). This also makes it clearer what
those abbreviations stand for. When I first saw the pylint section, I
was very confused by that, so other might be as well.
See it rendered here:
https://github.com/thomkeh/ruff/blob/patch-1/README.md#pylint-plc-ple-plr-plw
