refactor(lsp): accept only one Tool & ToolBuilder

[Sysix]

Pull request overview

Refactors the oxc_language_server LSP implementation to operate with a single Tool/ToolBuilder instead of managing multiple tools per workspace, simplifying worker creation and capability wiring.

[Sysix]

• fix(oxlint/lsp): error on unknown command #20841
• refactor(lsp): accept only one Tool & ToolBuilder #20840 👈 (View in Graphite)
• main

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[Copilot]

Pull request overview

Refactors the oxc_language_server LSP implementation to operate with a single Tool/ToolBuilder instead of managing multiple tools per workspace, simplifying worker creation and capability wiring.

Changes:

• Replaced tool/builder collections with single tool + builder in WorkspaceWorker and WorkerManager.
• Updated Backend/run_server APIs and call sites to pass a single ToolBuilder.
• Adjusted LSP and worker tests to construct and pass a single FakeToolBuilder.

Reviewed changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
crates/oxc_language_server/src/worker_manager.rs	Stores a single shared tool builder and passes it into new workers; updates tests accordingly.
crates/oxc_language_server/src/worker.rs	Switches from Vec<Tool> to a single optional tool and updates all tool interactions/shutdown/watchers.
crates/oxc_language_server/src/backend.rs	Uses the single tool builder to contribute server capabilities; Backend::new now accepts one builder.
crates/oxc_language_server/src/lib.rs	run_server signature updated to accept a single ToolBuilder.
crates/oxc_language_server/src/tests.rs	Updates integration-style tests to construct Backend with a single FakeToolBuilder.
apps/oxlint/src/lsp/mod.rs	Updates oxlint LSP entrypoint to pass one builder.
apps/oxfmt/src/lsp/mod.rs	Updates oxfmt LSP entrypoint to pass one builder.

Comments suppressed due to low confidence (1)

crates/oxc_language_server/src/worker.rs:189

• format_file still has logic/comments that assume multiple tools (e.g. “continue to the next tool”), but the worker now holds only one tool. Simplifying this to a single-tool flow (and updating the comment accordingly) would reduce confusion and make the intent clearer.

        for tool in self.tool.read().await.iter() {
            let edits = tool.run_format(document)?;
            // If no edits are made, continue to the next tool
            if edits.is_empty() {
                continue;
            }

[Copilot]

Pull request overview

Copilot reviewed 8 out of 8 changed files in this pull request and generated 2 comments.

[camc314]

Merge activity

• Mar 29, 4:07 PM UTC: The merge label '0-merge' was detected. This PR will be added to the Graphite merge queue once it meets the requirements.
• Mar 29, 4:07 PM UTC: camc314 added this pull request to the Graphite merge queue.
• Mar 29, 4:25 PM UTC: Merged by the Graphite merge queue.