[jtpio]

Fixes #735

This will allow downstreams like JupyterLab to better show recently used commands in the palette:

[jtpio]

Opened early for visibility and it's still a draft for now.

Gonna check if there could be some more generic API / hooks the palette could expose, so downstream like JupyterLab would own the implementation of the recent feature instead.

[Copilot]

Copilot review overview

🟢 Approval recommended

The implementation is backward compatible, documented, and comprehensively tested.

Review effort: Balanced
Findings: None

What changed in this PR

Adds extensibility for custom command-palette search ordering and command-trigger tracking.

Changes:

• Exposes overridable and reusable search APIs.
• Adds an itemTriggered signal.
• Adds coverage for custom results and trigger behavior.

File	Description
review/​api/​widgets.api.md	Records the new public API surface.
packages/​widgets/​src/​commandpalette.ts	Implements search extension points and trigger signaling.
packages/​widgets/​tests/​src/​commandpalette.spec.ts	Tests the new APIs and behavior.

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[krassowski]

Looks good to me. I was not sure if we need the search function exposed, but I see that is used in JupyterLab downstream PR.

Two non-blocking suggestions surfaced by a local review with an LLM:

• The palette does not activate any item while the query is empty, and an override of search() cannot change this rule. With a recent command pinned first, as in jupyterlab/jupyterlab#19175, pressing Enter right after opening the palette does not run that command. The user has to press Down first. Issue #735 names VS Code as the model, and in VS Code Enter on an empty query runs the most recent command. This can be tackled in a follow-up.
• A click on a header result always replaces the query with the category in lower case plus a space, and a subclass cannot change this. Clicking a custom Recently Used header causes the query to became recently used , and the palette then shows No commands found that match 'recently used '. The headers are still used in lab when using a command palette in the sidebar rather than model.

Again, neither has to be tackled right now but the first point does highlight a UX issue that could be annoying to some.

[jtpio]

Thanks for the review!

Addressed the first point with 97b06ff, this is what it looks like now with jupyterlab/jupyterlab#19175 :

jupyterlab-recent-commands-fix.mp4