feat(mcp): add LSP 3.17 tools and MCP resources for diagnostics#124
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…#115) Issue #116 — add four missing LSP tools: - get_signature_help: textDocument/signatureHelp (LSP 3.15) - go_to_implementation: textDocument/implementation (LSP 3.6) - go_to_type_definition: textDocument/typeDefinition (LSP 3.6) - get_inlay_hints: textDocument/inlayHint (LSP 3.17) All tools follow the existing 1-based MCP position convention and degrade gracefully when the LSP server does not support the capability. Issue #115 — expose LSP diagnostics as subscribable MCP resources: - resources/list returns lsp-diagnostics:/// URIs for open documents - resources/read returns cached diagnostics as JSON - resources/subscribe / unsubscribe register interest in push updates - Split-phase diagnostics_pump caches PublishDiagnostics before the MCP peer is captured, then fires notify_resource_updated for subscribed URIs URI codec (bridge::resources) uses url::Url::from_file_path for RFC 3986-conformant percent-encoding. Subscription set is capped at 1 000 entries. Workspace-root containment is enforced in both read_resource and subscribe via validate_path. Closes #116, Closes #115
Remove spawn_batch_with_notifications and spawn_with_notifications (no longer needed now that LspServer carries notification_rx directly). Add LspServer::take_notification_rx to extract the receiver before registering the server with the translator, replacing it with a dummy channel so the struct remains fully initialized. Extract register_servers helper to keep serve() within the 100-line clippy limit. Handle LspNotification::Progress variant added in main to fix the non-exhaustive match in diagnostics_pump.
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Add 7 sub-cases to ra_e2e_suite: - sc_get_signature_help, sc_go_to_implementation, sc_go_to_type_definition, sc_get_inlay_hints — cover the 4 tools added in #124 that had no e2e coverage against real rust-analyzer - sc_list_resources, sc_read_resource, sc_subscribe_unsubscribe_resource — cover the MCP resources path (list/read/subscribe/unsubscribe) end-to-end Add list_resources, read_resource, subscribe_resource, unsubscribe_resource to McpClient test helper. Add lib_rs_uri() helper that derives the lsp-diagnostics:// URI from the live resources/list response to avoid path-encoding drift on macOS canonicalised paths. Append lsp317_target() to the rust_workspace fixture as a stable anchor for the new sub-cases (append-only, no existing anchors disturbed). Closes #129, closes #130
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…#139) Add 7 sub-cases to ra_e2e_suite: - sc_get_signature_help, sc_go_to_implementation, sc_go_to_type_definition, sc_get_inlay_hints — cover the 4 tools added in #124 that had no e2e coverage against real rust-analyzer - sc_list_resources, sc_read_resource, sc_subscribe_unsubscribe_resource — cover the MCP resources path (list/read/subscribe/unsubscribe) end-to-end Add list_resources, read_resource, subscribe_resource, unsubscribe_resource to McpClient test helper. Add lib_rs_uri() helper that derives the lsp-diagnostics:// URI from the live resources/list response to avoid path-encoding drift on macOS canonicalised paths. Append lsp317_target() to the rust_workspace fixture as a stable anchor for the new sub-cases (append-only, no existing anchors disturbed). Closes #129, closes #130
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Summary
Implements two features together:
Issue #116 — 4 new LSP tools:
get_signature_help—textDocument/signatureHelp(LSP 3.15): method parameter hints at call-site positiongo_to_implementation—textDocument/implementation(LSP 3.6): navigate from trait/interface to concrete implementationsgo_to_type_definition—textDocument/typeDefinition(LSP 3.6): navigate to the type definition of an expressionget_inlay_hints—textDocument/inlayHint(LSP 3.17): inline type annotations over a rangeAll tools follow the existing 1-based MCP position convention and degrade gracefully when the LSP server lacks the capability.
Issue #115 — MCP resources for diagnostics:
resources/listreturnslsp-diagnostics:///URIs for open documentsresources/readreturns cached diagnostics as JSONresources/subscribe/unsubscriberegister interest in push updatesdiagnostics_pump: starts before MCP serve to avoid dropping first-paint diagnostics, firesnotify_resource_updatedfor subscribed URIs once peer is capturedurl::Url::from_file_pathwith percent-encodingread_resourceandsubscribeviavalidate_pathRefactoring (post-rebase cleanup):
spawn_batch_with_notifications(superseded byLspServer.notification_rxadded in main)LspServer::take_notification_rxto extract receiver before server registrationLspNotification::Progressvariant indiagnostics_pumpTest plan
cargo +nightly fmt --all -- --checkpassescargo clippy --all-targets --all-features --workspace -- -D warningspassescargo nextest run --workspace --all-features --lib --bins— 380/380 tests passRUSTDOCFLAGS="-D warnings" cargo doc --no-deps --all-featurespassesresources/listreturns URIs for open documentsCloses #116, Closes #115