If `allow-multiline = false` is set, then if the user enables `explicit-string-concatenation` (`ISC003`), there's no way for them to create valid multiline strings. This PR notes that they should turn off `ISC003`.
Closes#2362.
Ruff allows rules to be enabled with `select` and disabled with
`ignore`, where the more specific rule selector takes precedence,
for example:
`--select ALL --ignore E501` selects all rules except E501
`--ignore ALL --select E501` selects only E501
(If both selectors have the same specificity ignore selectors
take precedence.)
Ruff always had two quirks:
* If `pyproject.toml` specified `ignore = ["E501"]` then you could
previously not override that with `--select E501` on the command-line
(since the resolution didn't take into account that the select was
specified after the ignore).
* If `pyproject.toml` specified `select = ["E501"]` then you could
previously not override that with `--ignore E` on the command-line
(since the resolution didn't take into account that the ignore was
specified after the select).
Since d067efe265 (#1245)
`extend-select` and `extend-ignore` always override
`select` and `ignore` and are applied iteratively in pairs,
which introduced another quirk:
* If some `pyproject.toml` file specified `extend-select`
or `extend-ignore`, `select` and `ignore` became pretty much
unreliable after that with no way of resetting that.
This commit fixes all of these quirks by making later configuration
sources take precedence over earlier configuration sources.
While this is a breaking change, we expect most ruff configuration
files to not rely on the previous unintutive behavior.
This commit removes rule redirects such as ("U" -> "UP") from the
RuleCodePrefix enum because they complicated the generation of that enum
(which we want to change to be prefix-agnostic in the future).
To preserve backwards compatibility redirects are now resolved
before the strum-generated RuleCodePrefix::from_str is invoked.
This change also brings two other advantages:
* Redirects are now only defined once
(previously they had to be defined twice:
once in ruff_macros/src/rule_code_prefix.rs
and a second time in src/registry.rs).
* The deprecated redirects will no longer be suggested in IDE
autocompletion within pyproject.toml since they are now no
longer part of the ruff.schema.json.
At present, `ISC001` and `ISC002` flag concatenations like the following:
```py
"a" "b" # ISC001
"a" \
"b" # ISC002
```
However, multiline concatenations are allowed.
This PR adds a setting:
```toml
[tool.ruff.flake8-implicit-str-concat]
allow-multiline = false
```
Which extends `ISC002` to _also_ flag multiline concatenations, like:
```py
(
"a" # ISC002
"b"
)
```
Note that this is backwards compatible, as `allow-multiline` defaults to `true`.
This PR adds the scaffolding files for `flake8-type-checking`, along with the simplest rule (`empty-type-checking-block`), just as an example to get us started.
See: #1785.
More accurate since the enum also encompasses:
* ALL (which isn't a prefix at all)
* fully-qualified rule codes (which aren't prefixes unless you say
they're a prefix to the empty string but that's not intuitive)
Tracking issue: https://github.com/charliermarsh/ruff/issues/2024
Implementation for EXE003, EXE004 and EXE005 of `flake8-executable`
(shebang should contain "python", not have whitespace before, and should be on the first line)
Please take in mind that this is my first rust contribution.
The remaining EXE-rules are a combination of shebang (`lines.rs`), file permissions (`fs.rs`) and if-conditions (`ast.rs`). I was not able to find other rules that have interactions/dependencies in them. Any advice on how this can be best implemented would be very welcome.
For autofixing `EXE005`, I had in mind to _move_ the shebang line to the top op the file. This could be achieved by a combination of `Fix::insert` and `Fix::delete` (multiple fixes per diagnostic), or by implementing a dedicated `Fix::move`, or perhaps in other ways. For now I've left it out, but keen on hearing what you think would be most consistent with the package, and pointer where to start (if at all).
---
If you care about another testimonial:
`ruff` not only helps staying on top of the many excellent flake8 plugins and other Python code quality tools that are available, it also applies them at baffling speed.
(Planning to implement it soon for github.com/pandas-profiling/pandas-profiling (as largest contributor) and github.com/ing-bank/popmon.)
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.
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! :)
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.
