## Summary
This PR introduces a new mdtest option `system` that can either be
`in-memory` or `os`
where `in-memory` is the default.
The motivation for supporting `os` is so that we can write OS/system
specific tests
with mdtests. Specifically, I want to write mdtests for the module
resolver,
testing that module resolution is case sensitive.
## Test Plan
I tested that the case-sensitive module resolver test start failing when
setting `system = "os"`
This trait should eventually go away, so we rename it (and supporting
types) to make room for a new concrete `Diagnostic` type.
This commit is just the rename. In the next commit, we'll move it to a
different module.
## Summary
This PR adds support for an optional list of paths that should be
checked to `knot check`.
E.g. to only check the `src` directory
```sh
knot check src
```
The default is to check all files in the project but users can reduce
the included files by specifying one or multiple optional paths.
The main two challenges with adding this feature were:
* We now need to show an error when one of the provided paths doesn't
exist. That's why this PR now collects errors from the project file
indexing phase and adds them to the output diagnostics. The diagnostic
looks similar to ruffs (see CLI test)
* The CLI should pick up new files added to included folders. For
example, `knot check src --watch` should pick up new files that are
added to the `src` folder. This requires that we now filter the files
before adding them to the project. This is a good first step to
supporting `include` and `exclude`.
The PR makes two simplifications:
1. I didn't test the changes with case-insensitive file systems. We may
need to do some extra path normalization to support those well. See
https://github.com/astral-sh/ruff/issues/16400
2. Ideally, we'd accumulate the IO errors from the initial indexing
phase and subsequent incremental indexing operations. For example, we
should preserve the IO diagnostic for a non existing `test.py` if it was
specified as an explicit CLI argument until the file gets created and we
should show it again when the file gets deleted. However, this is
somewhat complicated because we'd need to track which files we revisited
(or were removed because the entire directory is gone). I considered
this too low a priority as it's worth dealing with right now.
The implementation doesn't support symlinks within the project but that
is the same as Ruff and is unchanged from before this PR.
Closes https://github.com/astral-sh/ruff/issues/14193
## Test Plan
Added CLI and file watching integration tests. Manually testing.
## Summary
This PR updates the formatter and linter to use the `PythonVersion`
struct from the `ruff_python_ast` crate internally. While this doesn't
remove the need for the `linter::PythonVersion` enum, it does remove the
`formatter::PythonVersion` enum and limits the use in the linter to
deserializing from CLI arguments and config files and moves most of the
remaining methods to the `ast::PythonVersion` struct.
## Test Plan
Existing tests, with some inputs and outputs updated to reflect the new
(de)serialization format. I think these are test-specific and shouldn't
affect any external (de)serialization.
---------
Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>
## Summary
This PR moves the `PythonVersion` struct from the
`red_knot_python_semantic` crate to the `ruff_python_ast` crate so that
it can be used more easily in the syntax error detection work. Compared
to that [prototype](https://github.com/astral-sh/ruff/pull/16090/) these
changes reduce us from 2 `PythonVersion` structs to 1.
This does not unify any of the `PythonVersion` *enums*, but I hope to
make some progress on that in a follow-up.
## Test Plan
Existing tests, this should not change any external behavior.
---------
Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>
## Summary
Add support for the `project.requires-python` field in `pyproject.toml`
files.
Fall back to the resolved lower bound of `project.requires-python` if
the `environment.python-version` field is `None` (or more accurately,
initialize `environment.python-version with `requires-python`'s lower
bound if left unspecified).
## UX design
There are two options on how we can handle the fallback to
`requires-python`'s lower bound:
1. Store the resolved lower bound in `environment.python-version` if
that field is `None` (Implemented in this PR)
2. Store the `requires-python` constraint separately.
There's no observed difference unless a user-level configuration (or any
other inherited configuration is used). Let's discuss it on the given
example
**User configuration**
```toml
[environment]
python-version = "3.10"
```
**Project configuration (`pyproject.toml`)**
```toml
[project]
name = "test"
requires-python = ">= 3.12"
[tool.knot]
# No environment table
```
The resolved version for 1. is 3.12 because the `requires-python`
constraint precedence takes precedence over the `python-version` in the
user configuration. 2. resolves to 3.10 because all `python-version`
constraints take precedence before falling back to `requires-python`.
Ruff implements 1. It's also the easier to implement and it does seem
intuitive to me that the more local `requires-python` constraint takes
precedence.
## Test plan
Added CLI and unit tests.
This essentially makes it impossible to construct a `Diagnostic`
that has a `TextRange` but no `File`.
This is meant to be a precursor to multi-span support.
(Note that I consider this more of a prototyping-change and not
necessarily what this is going to look like longer term.)
Reviewers can probably review this PR as one big diff instead of
commit-by-commit.
## Summary
This PR adds support for user-level configurations
(`~/.config/knot/knot.toml`) to Red Knot.
Red Knot will watch the user-level configuration file for changes but
only if it exists
when the process start. It doesn't watch for new configurations,
mainly to simplify things for now (it would require watching the entire
`.config` directory because the `knot` subfolder might not exist
either).
The new `ConfigurationFile` struct seems a bit overkill for now but I
plan to use it for
hierarchical configurations as well.
Red Knot uses the same strategy as uv and Ruff by using the etcetera
crate.
## Test Plan
Added CLI and file watching test
## Summary
This PR generalize the idea that we may want to emit diagnostics for
invalid or incompatible configuration values similar to how we already
do it for `rules`.
This PR introduces a new `Settings` struct that is similar to `Options`
but, unlike
`Options`, are fields have their default values filled in and they use a
representation optimized for reads.
The diagnostics created during loading the `Settings` are stored on the
`Project` so that we can emit them when calling `check`.
The motivation for this work is that it simplifies adding new settings.
That's also why I went ahead and added the `terminal.error-on-warning`
setting to demonstrate how new settings are added.
## Test Plan
Existing tests, new CLI test.
## Summary
Adds a JSON schema generation step for Red Knot. This PR doesn't yet add
a publishing step because it's still a bit early for that
## Test plan
I tested the schema in Zed, VS Code and PyCharm:
* PyCharm: You have to manually add a schema mapping (settings JSON
Schema Mappings)
* Zed and VS code support the inline schema specification
```toml
#:schema /Users/micha/astral/ruff/knot.schema.json
[environment]
extra-paths = []
[rules]
call-possibly-unbound-method = "error"
unknown-rule = "error"
# duplicate-base = "error"
```
```json
{
"$schema": "file:///Users/micha/astral/ruff/knot.schema.json",
"environment": {
"python-version": "3.13",
"python-platform": "linux2"
},
"rules": {
"unknown-rule": "error"
}
}
```
https://github.com/user-attachments/assets/a18fcd96-7cbe-4110-985b-9f1935584411
The Schema overall works but all editors have their own quirks:
* PyCharm: Hovering a name always shows the section description instead
of the description of the specific setting. But it's the same for other
settings in `pyproject.toml` files 🤷
* VS Code (JSON): Using the generated schema in a JSON file gives
exactly the experience I want
* VS Code (TOML):
* Properties with multiple possible values are repeated during
auto-completion without giving any hint how they're different. 
* The property description mushes together the description of the
property and the value, which looks sort of ridiculous. 
* Autocompletion and documentation hovering works (except the
limitations mentioned above)
* Zed:
* Very similar to VS Code with the exception that it uses the
description attribute to distinguish settings with multiple possible
values 
I don't think there's much we can do here other than hope (or help)
editors improve their auto completion. The same short comings also apply
to ruff, so this isn't something new. For now, I think this is good
enough
## Summary
- Add feature to specify a custom typeshed from within Markdown-based
tests
- Port "builtins" unit tests from `infer.rs` to Markdown tests, part of
#13696
## Test Plan
- Tests for the custom typeshed feature
- New Markdown tests for deleted Rust unit tests
## Summary
The `Options` struct is intended to capture the user's configuration
options but
`EnvironmentOptions::venv_path` supports both a `SitePackages::Known`
and `SitePackages::Derived`.
Users should only be able to provide `SitePackages::Derived`—they
specify a path to a venv, and Red Knot derives the path to the
site-packages directory. We'll only use the `Known` variant once we
automatically discover the Python installation.
That's why this PR changes `EnvironmentOptions::venv_path` from
`Option<SitePackages>` to `Option<SystemPathBuf>`.
This requires making some changes to the file watcher test, and I
decided to use `extra_paths` over venv path
because our venv validation is annoyingly correct -- making mocking a
venv rather involved.
## Test Plan
`cargo test`
