Add support for workspace symbols

[Copilot]

Overview

This PR implements workspace symbols support for the protols LSP server, enabling clients to search for symbols across all files in the workspace. This complements the existing document symbols feature by providing a global symbol search capability.

Changes

Server Capabilities

• Added workspace_symbol_provider to the LSP server capabilities advertised during initialization
• Registered the WorkspaceSymbolRequest handler in the server router

Implementation

The implementation adds a workspace_symbol method in src/lsp.rs that processes workspace symbol requests with query-based filtering. The method now includes full workspace parsing before symbol collection:

1. Full Workspace Parsing: Before collecting symbols, the handler parses all .proto files from all workspace folders (similar to references and rename capabilities), ensuring complete coverage
2. find_workspace_symbols in src/state.rs: Collects symbols from all parsed trees in the workspace, filters them based on the query string (case-insensitive substring match), and returns sorted results
3. collect_workspace_symbols in src/state.rs: Recursively traverses document symbols to extract workspace symbols, maintaining parent-child relationships via the container_name field
4. get_workspaces in src/config/workspace.rs: New helper method to retrieve all workspace folder URIs

Features

• Full workspace coverage: Parses all proto files in all workspace folders, not just opened files and their imports
• Cross-file symbol search: Search for messages, enums, and other symbols across all proto files in the workspace
• Query filtering: Case-insensitive substring matching on symbol names
• Nested symbol support: Correctly handles and reports nested messages with their container names
• Consistent ordering: Results are sorted alphabetically by name and then by URI for predictable behavior
• Progress reporting: Supports LSP work done progress tokens for long-running workspace parsing operations

Example Usage

When a client sends a workspace/symbol request with query "author":

{
  "query": "author"
}

The server parses all workspace files and returns all symbols matching "author" across the workspace:

[
  {
    "name": "Author",
    "kind": 23,
    "location": {
      "uri": "file:///path/to/b.proto",
      "range": { "start": { "line": 5, "character": 0 }, ... }
    }
  }
]

Testing

Added comprehensive test coverage in src/workspace/workspace_symbol.rs:

• Test with empty query (returns all symbols)
• Test with specific queries ("author", "address")
• Test that non-matching queries return empty results
• Uses insta snapshot testing for regression protection

All 29 tests pass successfully (28 existing + 1 new).

Fixes #21

Original prompt

---

This section details on the original issue you should resolve

<issue_title>Add support for workspace symbols</issue_title>
<issue_description>We already support document symbols, it's time to support workspace symbols as well.</issue_description>

Comments on the Issue (you are @copilot in this section)

@coder3101 can be re-opened if requested.

Fixes #21

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[hujianxin]

I found that your new protols only recognizes symbols of files I have accessed, and does not actively index files that have not been accessed.

[coder3101]

Workspace symbols need full workspace parsing, similar to what references or rename capabilities, otherwise for most of other capabilities, we only parse the opened and recursively imported files.

Probably, AI got this wrong and let me nudge it in the right direction or will take a look at it over the weekend.

[coder3101]

@copilot the PR looks good but it only shows the workspace symbols of opened files and files imported by it, when workspace symbols is requested we should fallback to full workspace parsing similar to rename and references. Please update the PR to take this into account.

[Copilot]

@copilot the PR looks good but it only shows the workspace symbols of opened files and files imported by it, when workspace symbols is requested we should fallback to full workspace parsing similar to...

Updated the implementation to parse all workspace files before collecting symbols, similar to how references and rename work. The workspace_symbol method now:

1. Gets all workspace folders via get_workspaces()
2. Calls parse_all_from_workspace() for each workspace
3. Supports progress reporting for the parsing operation
4. Then collects symbols from all parsed trees

Changes in commit: Will be included in the next commit message.

[hujianxin]

@coder3101 new commit looks good for me, I don't know if it need some cache or something to speed up workspace symbols lookup, but it works for now, I feel good, thanks

[coder3101]

I will merge these changes after a review, thanks for confirming that it works.

Caching can be a follow up if requested.

[coder3101]

I will do a commit for non functional changes over the weekend before merging. In the meantime time feel free to use this branch for your testing.

[abrassel]

Hi folks, I think this branch is not quite ready yet. I would love to finish this feature, if you know what work remains.

[coder3101]

Yes please, go ahead!

[abrassel]

Great, thank you! Do you know what work remains to be done?

[coder3101]

I believe testing is needed, simple symbol, nested symbols, across different packages etc. Apart from that some lint issue with cargo clippy and that should be all.

Depending on the testing some other fixes might be needed, or else good for merge.