## Summary
This PR is a spin-off from https://github.com/astral-sh/ruff/pull/19415.
It enables replacing the severity and lint name in a ty-style
diagnostic:
```
error[unused-import]: `os` imported but unused
```
with the noqa code and optional fix availability icon for a Ruff
diagnostic:
```
F401 [*] `os` imported but unused
F821 Undefined name `a`
```
or nothing at all for a Ruff syntax error:
```
SyntaxError: Expected one or more symbol names after import
```
Ruff adds the `SyntaxError` prefix to these messages manually.
Initially (d912458), I just passed a `hide_severity` flag through a
bunch of calls to get it into `annotate-snippets`, but after looking at
it again today, I think reusing the `None` severity/level gave a nicer
result. As I note in a lengthy code comment, I think all of this code
should be temporary and reverted when Ruff gets real severities, so
hopefully it's okay if it feels a little hacky.
I think the main visible downside of this approach is that we can't
style the asterisk in the fix availabilty icon in cyan, as in Ruff's
current output. It's part of the message in this PR and any styling gets
overwritten in `annotate-snippets`.
<img width="400" height="342" alt="image"
src="https://github.com/user-attachments/assets/57542ec9-a81c-4a01-91c7-bd6d7ec99f99"
/>
Hmm, I guess reusing `Level::None` also means the `F401` isn't red
anymore. Maybe my initial approach was better after all. In any case,
the rest of the PR should be basically the same, it just depends how we
want to toggle the severity.
## Test Plan
New `ruff_db` tests. These snapshots should be compared to the two tests
just above them (`hide_severity_output` vs `output` and
`hide_severity_syntax_errors` against `syntax_errors`).
## Summary
This PR partially addresses #16418 via the following:
- `LinterSettings::unresolved_python_version` is now a `TargetVersion`,
which is a thin wrapper around an `Option<PythonVersion>`
- `Checker::target_version` now calls `TargetVersion::linter_version`
internally, which in turn uses `unwrap_or_default` to preserve the
current default behavior
- Calls to the parser now call `TargetVersion::parser_version`, which
calls `unwrap_or_else(PythonVersion::latest)`
- The `Checker`'s implementation of
`SemanticSyntaxContext::python_version` also uses
`TargetVersion::parser_version` to use `PythonVersion::latest` for
semantic errors
In short, all lint rule behavior should be unchanged, but we default to
the latest Python version for the new syntax errors, which should
minimize confusing version-related syntax errors for users without a
version configured.
## Test Plan
Existing tests, which showed no changes (except for printing default
settings).
Summary
--
This PR updates `check_path` in the `ruff_linter` crate to return a
`Vec<Message>` instead of a `Vec<Diagnostic>`. The main motivation for
this is to make it easier to convert semantic syntax errors directly
into `Message`s rather than `Diagnostic`s in #16106. However, this also
has the benefit of keeping the preview check on unsupported syntax
errors in `check_path`, as suggested in
https://github.com/astral-sh/ruff/pull/16429#discussion_r1974748024.
All of the interesting changes are in the first commit. The second
commit just renames variables like `diagnostics` to `messages`, and the
third commit is a tiny import fix.
I also updated the `ExpandedMessage::location` field name, which caused
a few extra commits tidying up the playground code. I thought it was
nicely symmetric with `end_location`, but I'm happy to revert that too.
Test Plan
--
Existing tests. I also tested the playground and server manually.
## Summary
This PR updates the playground to show syntax errors.
(I forgot to update this and noticed it this morning.)
## Test Plan
Build the playground locally and preview it:
<img width="764" alt="Screenshot 2024-06-28 at 11 03 35"
src="1fd48d6c-ae41-4672-bf3c-32a61d9946ef">
## Summary
Previously, `StmtIf` was defined recursively as
```rust
pub struct StmtIf {
pub range: TextRange,
pub test: Box<Expr>,
pub body: Vec<Stmt>,
pub orelse: Vec<Stmt>,
}
```
Every `elif` was represented as an `orelse` with a single `StmtIf`. This
means that this representation couldn't differentiate between
```python
if cond1:
x = 1
else:
if cond2:
x = 2
```
and
```python
if cond1:
x = 1
elif cond2:
x = 2
```
It also makes many checks harder than they need to be because we have to
recurse just to iterate over an entire if-elif-else and because we're
lacking nodes and ranges on the `elif` and `else` branches.
We change the representation to a flat
```rust
pub struct StmtIf {
pub range: TextRange,
pub test: Box<Expr>,
pub body: Vec<Stmt>,
pub elif_else_clauses: Vec<ElifElseClause>,
}
pub struct ElifElseClause {
pub range: TextRange,
pub test: Option<Expr>,
pub body: Vec<Stmt>,
}
```
where `test: Some(_)` represents an `elif` and `test: None` an else.
This representation is different tradeoff, e.g. we need to allocate the
`Vec<ElifElseClause>`, the `elif`s are now different than the `if`s
(which matters in rules where want to check both `if`s and `elif`s) and
the type system doesn't guarantee that the `test: None` else is actually
last. We're also now a bit more inconsistent since all other `else`,
those from `for`, `while` and `try`, still don't have nodes. With the
new representation some things became easier, e.g. finding the `elif`
token (we can use the start of the `ElifElseClause`) and formatting
comments for if-elif-else (no more dangling comments splitting, we only
have to insert the dangling comment after the colon manually and set
`leading_alternate_branch_comments`, everything else is taken of by
having nodes for each branch and the usual placement.rs fixups).
## Merge Plan
This PR requires coordination between the parser repo and the main ruff
repo. I've split the ruff part, into two stacked PRs which have to be
merged together (only the second one fixes all tests), the first for the
formatter to be reviewed by @michareiser and the second for the linter
to be reviewed by @charliermarsh.
* MH: Review and merge
https://github.com/astral-sh/RustPython-Parser/pull/20
* MH: Review and merge or move later in stack
https://github.com/astral-sh/RustPython-Parser/pull/21
* MH: Review and approve
https://github.com/astral-sh/RustPython-Parser/pull/22
* MH: Review and approve formatter PR
https://github.com/astral-sh/ruff/pull/5459
* CM: Review and approve linter PR
https://github.com/astral-sh/ruff/pull/5460
* Merge linter PR in formatter PR, fix ecosystem checks (ecosystem
checks can't run on the formatter PR and won't run on the linter PR, so
we need to merge them first)
* Merge https://github.com/astral-sh/RustPython-Parser/pull/22
* Create tag in the parser, update linter+formatter PR
* Merge linter+formatter PR https://github.com/astral-sh/ruff/pull/5459
---------
Co-authored-by: Micha Reiser <micha@reiser.io>