impl Class Hierarchy #2207

[asukaminato0721]

Summary

Fixes part of #2207

ref microsoft/pylance-release#4972 (comment)

Added a client-side Python CodeLens provider that shows:
- $(arrow-up) Overrides ... on overriding methods
- $(arrow-down) Implemented by ... / implementation counts on parent methods
Registered the provider plus navigation/quick-pick commands

Implemented the provider

Test Plan

Added backend regression coverage for that parent-resolution path

[Copilot]

Pull request overview

This PR adds an overrides/implementations CodeLens experience for Python in the VS Code extension and extends the backend go-to-declaration behavior so overriding members can navigate to the overridden parent declaration (supporting class hierarchy/navigation work tracked in #2207).

Changes:

• Added a new VS Code OverrideCodeLensProvider that shows “Overrides …” and “Implemented by …” lenses based on declaration/implementation providers.
• Registered the provider and navigation/quick-pick commands in the extension activation flow.
• Updated backend goto_declaration to redirect overriding members to parent declarations, and added regression tests for method + class attribute overrides.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 6 comments.

File	Description
pyrefly/lib/test/lsp/definition.rs	Adds tests validating go-to-declaration jumps from overrides to parent declarations.
pyrefly/lib/state/lsp.rs	Adds override-parent lookup logic to goto_declaration plus a helper for resolving module info from a ModulePath.
lsp/src/overrideCodeLens.ts	Implements the CodeLens provider and navigation commands for override/implementation targets.
lsp/src/extension.ts	Registers the CodeLens provider, hooks refreshes, and registers navigation commands.

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[Copilot]

Refreshing CodeLenses on every onDidChangeTextDocument for Python means this provider will re-run (and potentially issue many LSP requests) on every keystroke. Consider debouncing this refresh (timer-based) and/or refreshing only on saves / when the edited document is the active editor to reduce churn.

[Copilot]

parent_declarations_for_definition always reads the solutions index for the current handle, but it looks up overrides by definition.range (a TextRange without module identity). If find_definition returns a definition in another module (e.g. imports/stubs), this can either miss the override info or accidentally match an unrelated range in the current module and return incorrect parent declarations. Consider only applying this override-redirect when definition.module.path() matches the current module, or resolve the correct handle/index for definition.module before consulting parent_methods_map.

[meta-codesync]

This pull request has been imported. If you are a Meta employee, you can view this in D113979798. (Because this pull request was imported automatically, there will not be any future comments.)

[codspeed-hq]

Merging this PR will not alter performance

✅ 11 untouched benchmarks
⏩ 3 skipped benchmarks¹

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_{Comparing asukaminato0721:2207-4972 (5bd5be4) with main (3ad3a27)}

Footnotes

1. 3 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

[github-actions]

According to mypy_primer, this change doesn't affect type check results on a corpus of open source code. ✅