Add new LSP extension for workspace symbol lookup

The new extension allows filtering of workspace symbool lookup
results by search scope or search kind.

Filtering can be configured in 3 different ways:

 - The '#' or '*' markers can be added inline with the symbol lookup
   query.

   The '#' marker means symbols should be looked up in the current
   workspace and any dependencies. If not specified, only current
   workspace is considered.

   The '*' marker means all kinds of symbols should be looked up
   (types, functions, etc). If not specified, only type symbols are
   returned.

 - Each LSP request can take an optional search_scope or search_kind
   argument query parameter.

 - Finally there are 2 global config options that can be set for all
   requests served by the active RA instance.

Add support for setting the global config options to the VSCode
extension.
The extension does not use the per-request way, but it's useful for
other IDEs.

The latest version of VSCode filters out the inline markers, so
currently the only reasonable way to use the new functionality is
via the global config.

1 files changed, 5 insertions, 0 deletions

diff --git a/crates/ide_db/src/symbol_index.rs b/crates/ide_db/src/symbol_index.rs
index da427d686..0f5c4abc4 100644
--- a/crates/ide_db/src/symbol_index.rs
+++ b/crates/ide_db/src/symbol_index.rs
@@ -161,6 +161,11 @@ impl<DB: ParallelDatabase> Clone for Snap<salsa::Snapshot<DB>> {
 // That is, `#` switches from "types" to all symbols, `*` switches from the current
 // workspace to dependencies.
 //
+// Note that filtering does not currently work in VSCode due to the editor never
+// sending the special symbols to the language server. Instead, you can configure
+// the filtering via the `rust-analyzer.workspace.symbol.search.scope` and
+// `rust-analyzer.workspace.symbol.search.kind` settings.
+//
 // |===
 // | Editor  | Shortcut
 //