fix(#102): handle external file changes via stat-resync, didChangeWatchedFiles, and a populated diagnostics cache

CHANGELOG.md

@@ -16,6 +16,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - **RFC-3986 URI codec** — `bridge::resources` module with percent-encoding via `url::Url::from_file_path`; empty-authority injection is rejected to prevent UNC-path attacks on Windows
 - **Subscription cap** — `ResourceSubscriptions` enforces a `MAX_SUBSCRIPTIONS = 1_000` limit per session to guard against memory exhaustion
 - **MCP tools** — `get_signature_help` (`textDocument/signatureHelp`), `go_to_implementation` (`textDocument/implementation`), `go_to_type_definition` (`textDocument/typeDefinition`), and `get_inlay_hints` (`textDocument/inlayHint`) tools exposing LSP 3.6/3.15/3.17 capabilities (#116)
+- **`workspace/didChangeWatchedFiles` support** (#102, part 2) — mcpls now declares `workspace.didChangeWatchedFiles.dynamic_registration: true` and `relative_pattern_support: true`, handles inbound `client/registerCapability` and `client/unregisterCapability` requests, and runs a per-server filesystem watcher that forwards matched events as `workspace/didChangeWatchedFiles`. This keeps the LSP server's *workspace index* live across external file changes (files mcpls has never opened) for servers that register watchers (rust-analyzer, gopls, pyright, typescript-language-server, clangd). Builds on a new `notify` dependency.
+- **`workspace.diagnostics_mode` config option** — selects how `get_diagnostics` sources its results: `pull` (LSP `textDocument/diagnostic` only — misses rust-analyzer's flycheck output), `cached` (read the `publishDiagnostics` cache), or `hybrid` (pull + cached, deduplicated). Default is `hybrid`. Hybrid dedup keys on `(range, severity, code)` when a code is present and falls back to a path-qualifier-stripped message otherwise, so rust-analyzer's `DocItem` vs `types::DocItem` style duplicates collapse without dropping legitimately-distinct errors that share a span.
 
 ### Changed
 
@@ -26,6 +28,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - **LSP server requests** — Handle server-to-client requests such as `client/registerCapability`, fixing tsgo timeouts.
 - **Integration tests** — Add `[workspace]` table to `tests/fixtures/rust_workspace/Cargo.toml` so cargo treats the fixture as a standalone workspace; fixes 8 rust-analyzer integration tests that failed with "Failed to load workspaces." (#118)
 - **e2e coverage** — Add ra_e2e sub-cases for `get_signature_help`, `go_to_implementation`, `go_to_type_definition`, `get_inlay_hints` (4 LSP 3.17 tools from #124 had no coverage); add `list_resources`, `read_resource`, `subscribe_resource`, `unsubscribe_resource` to `McpClient` and ra_e2e_suite (MCP resources path was entirely untested) (#129, #130)
+- **Stale results after external file changes** (#102, part 1) — `DocumentTracker::ensure_open` now stats the file on every call and re-syncs the document with the LSP server (via `textDocument/didClose` + bumped-version `textDocument/didOpen`) when the on-disk signature has changed. Fixes stale `get_hover`, `get_definition`, `get_references`, `get_document_symbols`, `get_diagnostics`, `get_completions`, `get_code_actions`, `format_document`, `rename_symbol`, and call-hierarchy results after edits made outside mcpls (`git stash`/`checkout`, the MCP host's own `Edit`/`Write` tools, formatters, code generators). Works for every configured LSP, including those that do not register `workspace/didChangeWatchedFiles`.
+- **`get_cached_diagnostics` now returns actual data** — previously the `NotificationCache` existed but was never populated in production: the LSP client received `publishDiagnostics`, `window/logMessage`, and `window/showMessage` notifications and dropped them on the floor. mcpls now wires the notification channel through to a per-server pump task that updates the cache. This also makes the new `hybrid` diagnostics mode work.
 
 ## [0.3.6] - 2026-04-21
 

Cargo.toml

@@ -23,9 +23,11 @@ chrono = "0.4.44"
 clap = "4.6"
 dirs = "6.0"
 futures = "0.3"
+globset = "0.4"
 ignore = "0.4"
 lsp-types = "0.97"
 mcpls-core = { path = "crates/mcpls-core", version = "0.3.6" }
+notify = "8.0"
 predicates = "3.1"
 rmcp = "1.6.0"
 rstest = "0.26"

crates/mcpls-core/Cargo.toml

@@ -15,8 +15,10 @@ async-trait = { workspace = true }
 chrono = { workspace = true }
 dirs = { workspace = true }
 futures = { workspace = true }
+globset = { workspace = true }
 ignore = { workspace = true }
 lsp-types = { workspace = true }
+notify = { workspace = true }
 rmcp = { workspace = true, features = ["server", "transport-io", "macros"] }
 axum = { workspace = true, optional = true }
 tokio-util = { workspace = true, optional = true, features = ["rt"] }

crates/mcpls-core/src/bridge/mod.rs

@@ -14,7 +14,7 @@ pub use notifications::{
     DiagnosticInfo, LogEntry, LogLevel, MessageType, NotificationCache, ServerMessage,
 };
 pub use resources::ResourceSubscriptions;
-pub use state::{DocumentState, DocumentTracker, path_to_uri, uri_to_path};
+pub use state::{DocumentState, DocumentTracker, SyncSignature, path_to_uri, uri_to_path};
 pub use translator::{
     Completion, CompletionsResult, DefinitionResult, Diagnostic, DiagnosticSeverity,
     DiagnosticsResult, DocumentChanges, DocumentSymbolsResult, FormatDocumentResult, HoverResult,