fix: avoid redundant workspace reloads on startup

[lewis6991]

Summary

• ignore workspace/didChangeConfiguration notifications when the effective client config is unchanged
• avoid the extra full reindex when startup bootstraps through reload_workspace_files
• keep regression coverage for both the no-op config notification path and the startup reload path

Testing

• cargo test -p emmylua_code_analysis reload_workspace_files_
• cargo test -p emmylua_ls config_reload_is_not_cancelled_by_reindex

[gemini-code-assist]

Code Review

This pull request introduces optimizations to the workspace reloading process by skipping reindexing when no non-standard local files are present and avoiding configuration reloads if the client configuration remains unchanged. It also adds unit tests to verify these behaviors. Feedback focuses on improving the idiomatic nature of the Rust code by avoiding side effects in iterator filters and ensuring tests use temporary directories for better isolation.

[gemini-code-assist]

Using a side-effect inside a filter closure makes the code less readable and harder to reason about. A more idiomatic and clearer approach would be to separate the check for existing files from the filtering logic. For example, you could use peekable() on the iterator to check if it's empty before proceeding to collect the stale URIs. This would make the intent of the code more explicit.

[gemini-code-assist]

These tests create files in the current working directory and do not clean them up, which can pollute the development environment. It's best practice for tests to be self-contained. Please use a temporary directory for test files and ensure they are cleaned up. The tempfile crate is great for this and will handle cleanup automatically. You'll need to add tempfile to your [dev-dependencies].

mod tests {
    use super::*;

    #[test]
    fn reload_workspace_files_skips_reindex_when_bootstrapping_workspace() {
        let temp_dir = tempfile::tempdir().unwrap();
        let workspace_root = temp_dir.path().to_path_buf();
        let mut analysis = EmmyLuaAnalysis::new();
        let file_path = workspace_root.join("__reload_workspace_startup_test.lua");
        analysis.add_main_workspace(workspace_root);

        analysis.reload_workspace_files(
            vec![(file_path.clone(), Some("return true\n".to_string()))],
            Vec::new(),
        );

        assert_eq!(analysis.reindex_count, 0);
        assert!(
            analysis
                .get_file_id(&file_path_to_uri(&file_path).unwrap())
                .is_some()
        );
    }

    #[test]
    fn reload_workspace_files_reindexes_existing_workspace_files() {
        let temp_dir = tempfile::tempdir().unwrap();
        let workspace_root = temp_dir.path().to_path_buf();
        let mut analysis = EmmyLuaAnalysis::new();
        let file_path = workspace_root.join("__reload_workspace_existing_test.lua");
        analysis.add_main_workspace(workspace_root);
        analysis.update_files_by_path(vec![(file_path.clone(), Some("return true\n".to_string()))]);

        analysis.reload_workspace_files(
            vec![(file_path, Some("return false\n".to_string()))],
            Vec::new(),
        );

        assert_eq!(analysis.reindex_count, 1);
    }
}