This PR has several components:
* Introduce a Docstring String wrapper type that has render_plaintext
and render_markdown methods, to force docstring handlers to pick a
rendering format
* Implement [PEP-257](https://peps.python.org/pep-0257/) docstring
trimming for it
* The markdown rendering just renders the content in a plaintext
codeblock for now (followup work)
* Introduce a `DefinitionsOrTargets` type representing the partial
evaluation of `GotoTarget::get_definition_targets` to ideally stop at
getting `ResolvedDefinitions`
* Add `declaration_targets`, `definition_targets`, and `docstring`
methods to `DefinitionsOrTargets` for the 3 usecases we have for this
operation
* `docstring` is of course the key addition here, it uses the same basic
logic that `signature_help` was using: first check the goto-declaration
for docstrings, then check the goto-definition for docstrings.
* Refactor `signature_help` to use the new APIs instead of implementing
it itself
* Not fixed in this PR: an issue I found where `signature_help` will
erroneously cache docs between functions that have the same type (hover
docs don't have this bug)
* A handful of new tests and additions to tests to add docstrings in
various places and see which get caught
Examples of it working with stdlib, third party, and local definitions:
<img width="597" height="120" alt="Screenshot 2025-08-12 at 2 13 55 PM"
src="https://github.com/user-attachments/assets/eae54efd-882e-4b50-b5b4-721595224232"
/>
<img width="598" height="281" alt="Screenshot 2025-08-12 at 2 14 06 PM"
src="https://github.com/user-attachments/assets/5c9740d5-a06b-4c22-9349-da6eb9a9ba5a"
/>
<img width="327" height="180" alt="Screenshot 2025-08-12 at 2 14 18 PM"
src="https://github.com/user-attachments/assets/3b5647b9-2cdd-4c5b-bb7d-da23bff1bcb5"
/>
Notably modules don't work yet (followup work):
<img width="224" height="83" alt="Screenshot 2025-08-12 at 2 14 37 PM"
src="https://github.com/user-attachments/assets/7e9dcb70-a10e-46d9-a85c-9fe52c3b7e7b"
/>
Notably we don't show docs for an item if you hover its actual
definition (followup work, but also, not the most important):
<img width="324" height="69" alt="Screenshot 2025-08-12 at 2 16 54 PM"
src="https://github.com/user-attachments/assets/d4ddcdd8-c3fc-4120-ac93-cefdf57933b4"
/>
## Summary
This PR adds a new `ty.inlayHints.variableTypes` server setting to
configure ty to include / exclude inlay hints at variable position.
Currently, we only support inlay hints at this position so this option
basically translates to enabling / disabling inlay hints for now :)
The VS Code extension PR is
https://github.com/astral-sh/ty-vscode/pull/112.
closes: astral-sh/ty#472
## Test Plan
Add E2E tests.
This PR adds support for the "rename" language server feature. It builds
upon existing functionality used for "go to references".
The "rename" feature involves two language server requests. The first is
a "prepare rename" request that determines whether renaming should be
possible for the identifier at the current offset. The second is a
"rename" request that returns a list of file ranges where the rename
should be applied.
Care must be taken when attempting to rename symbols that span files,
especially if the symbols are defined in files that are not part of the
project. We don't want to modify code in the user's Python environment
or in the vendored stub files.
I found a few bugs in the "go to references" feature when implementing
"rename", and those bug fixes are included in this PR.
---------
Co-authored-by: UnboundVariable <unbound@gmail.com>
This PR adds support for the "selection range" language server feature.
This feature was recently requested by a ty user in [this feature
request](https://github.com/astral-sh/ty/issues/882).
This feature allows a client to implement "smart selection expansion"
based on the structure of the parse tree. For example, if you type
"shift-ctrl-right-arrow" in VS Code, the current selection will be
expanded to include the parent AST node. Conversely,
"shift-ctrl-left-arrow" shrinks the selection.
We will probably need to tune the granularity of selection expansion
based on user feedback. The initial implementation includes most AST
nodes, but users may find this to be too fine-grained. We have the
option of skipping some AST nodes that are not as meaningful when
editing code.
Co-authored-by: UnboundVariable <unbound@gmail.com>
This PR adds support for "document symbols" and "workspace symbols"
language server features. Most of the logic to implement these features
is shared.
The "document symbols" feature returns a list of all symbols within a
specified source file. Clients can specify whether they want a flat or
hierarchical list. Document symbols are typically presented by a client
in an "outline" form. Here's what this looks like in VS Code, for
example.
<img width="240" height="249" alt="image"
src="https://github.com/user-attachments/assets/82b11f4f-32ec-4165-ba01-d6496ad13bdf"
/>
The "workspace symbols" feature returns a list of all symbols across the
entire workspace that match some user-supplied query string. This allows
the user to quickly find and navigate to any symbol within their code.
<img width="450" height="134" alt="image"
src="https://github.com/user-attachments/assets/aac131e0-9464-4adf-8a6c-829da028c759"
/>
---------
Co-authored-by: UnboundVariable <unbound@gmail.com>
This PR adds support for the "document highlights" language server
feature.
This feature allows a client to highlight all instances of a selected
name within a document. Without this feature, editors perform
highlighting based on a simple text match. This adds semantic knowledge.
The implementation of this feature largely overlaps that of the
recently-added "references" feature. This PR refactors the existing
"references.rs" module, separating out the functionality and tests that
are specific to the other language feature into a "goto_references.rs"
module. The "references.rs" module now contains the functionality that
is common to "goto references", "document highlights" and "rename"
(which is not yet implemented).
As part of this PR, I also created a new `ReferenceTarget` type which is
similar to the existing `NavigationTarget` type but better suited for
references. This idea was suggested by @MichaReiser in [this code review
feedback](https://github.com/astral-sh/ruff/pull/19475#discussion_r2224061006)
from a previous PR. Notably, this new type contains a field that
specifies the "kind" of the reference (read, write or other). This
"kind" is needed for the document highlights feature.
Before: all textual instances of `foo` are highlighted
<img width="156" height="126" alt="Screenshot 2025-07-23 at 12 51 09 PM"
src="https://github.com/user-attachments/assets/37ccdb2f-d48a-473d-89d5-8e89cb6c394e"
/>
After: only semantic matches are highlighted
<img width="164" height="157" alt="Screenshot 2025-07-23 at 12 52 05 PM"
src="https://github.com/user-attachments/assets/2efadadd-4691-4815-af04-b031e74c81b7"
/>
---------
Co-authored-by: UnboundVariable <unbound@gmail.com>
This PR implements "go to definition" and "go to declaration"
functionality for name nodes only. Future PRs will add support for
attributes, module names in import statements, keyword argument names,
etc.
This PR:
* Registers a declaration and definition request handler for the
language server.
* Splits out the `goto_type_definition` into its own module. The `goto`
module contains functionality that is common to `goto_type_definition`,
`goto_declaration` and `goto_definition`.
* Roughs in a new module `stub_mapping` that is not yet implemented. It
will be responsible for mapping a definition in a stub file to its
corresponding definition(s) in an implementation (source) file.
* Adds a new IDE support function `definitions_for_name` that collects
all of the definitions associated with a name and resolves any imports
(recursively) to find the original definitions associated with that
name.
* Adds a new `VisibleAncestorsIter` stuct that iterates up the scope
hierarchy but skips scopes that are not visible to starting scope.
---------
Co-authored-by: UnboundVariable <unbound@gmail.com>
This PR includes:
* Implemented core signature help logic
* Added new docstring method on Definition that returns a docstring for
function and class definitions
* Modified the display code for Signature that allows a signature string
to be broken into text ranges that correspond to each parameter in the
signature
* Augmented Signature struct so it can track the Definition for a
signature when available; this allows us to find the docstring
associated with the signature
* Added utility functions for parsing parameter documentation from three
popular docstring formats (Google, NumPy and reST)
* Implemented tests for all of the above
"Signature help" is displayed by an editor when you are typing a
function call expression. It is typically triggered when you type an
open parenthesis. The language server provides information about the
target function's signature (or multiple signatures), documentation, and
parameters.
Here is how this appears:

---------
Co-authored-by: UnboundVariable <unbound@gmail.com>
Co-authored-by: Micha Reiser <micha@reiser.io>
This PR implements a basic semantic token provider for ty's language
server. This allows for more accurate semantic highlighting / coloring
within editors that support this LSP functionality.
Here are screen shots that show how code appears in VS Code using the
"rainbow" theme both before and after this change.


The token types and modifier tags in this implementation largely mirror
those used in Microsoft's default language server for Python.
The implementation supports two LSP interfaces. The first provides
semantic tokens for an entire document, and the second returns semantic
tokens for a requested range within a document.
The PR includes unit tests. It also includes comments that document
known limitations and areas for future improvements.
---------
Co-authored-by: UnboundVariable <unbound@gmail.com>
This commit does a small refactor to combine the file and
cursor offset into a single type. I think this makes it
clearer that even if there are multiple files in the cursor
test, this one in particular corresponds to the file that
contains the `<CURSOR>` marker.
This doesn't change any functionality of the cursor tests, but does
re-arrange the code a bit. Firstly, it's now in a builder. And secondly,
there's an API to add multiple files to the test (but exactly one must
have a `<CURSOR>` marker).
## Summary
This PR is a first step toward integration of the new `Diagnostic` type
into ruff. There are two main changes:
- A new `UnifiedFile` enum wrapping `File` for red-knot and a
`SourceFile` for ruff
- ruff's `Message::SyntaxError` variant is now a `Diagnostic` instead of
a `SyntaxErrorMessage`
The second of these changes was mostly just a proof of concept for the
first, and it went pretty smoothly. Converting `DiagnosticMessage`s will
be most of the work in replacing `Message` entirely.
## Test Plan
Existing tests, which show no changes.
---------
Co-authored-by: Carl Meyer <carl@astral.sh>
Co-authored-by: Micha Reiser <micha@reiser.io>