Allow forwarding of the indexedRename request to clangd

The main purpose of this is so we can invoke it from `SkipUnless` to see if `clangd` supports the `workspace/indexedRename` request.

Author: ahoppen

Sources/SourceKitLSP/Clang/ClangLanguageServer.swift

@@ -609,6 +609,10 @@ extension ClangLanguageServerShim {
     throw ResponseError.unknown("unsupported method")
   }
 
+  func indexedRename(_ request: IndexedRenameRequest) async throws -> WorkspaceEdit? {
+    return try await forwardRequestToClangd(request)
+  }
+
   // MARK: - Other
 
   func executeCommand(_ req: ExecuteCommandRequest) async throws -> LSPAny? {

Sources/SourceKitLSP/Rename.swift

@@ -759,6 +759,14 @@ extension SourceKitServer {
     prepareRenameResult.placeholder = oldName.definitionName
     return prepareRenameResult
   }
+
+  func indexedRename(
+    _ request: IndexedRenameRequest,
+    workspace: Workspace,
+    languageService: ToolchainLanguageServer
+  ) async throws -> WorkspaceEdit? {
+    return try await languageService.indexedRename(request)
+  }
 }
 
 // MARK: - Swift

Sources/SourceKitLSP/SourceKitServer.swift

@@ -919,6 +919,8 @@ extension SourceKitServer: MessageHandler {
       await self.handleRequest(for: request, requestHandler: self.documentDiagnostic)
     case let request as RequestAndReply<PrepareRenameRequest>:
       await self.handleRequest(for: request, requestHandler: self.prepareRename)
+    case let request as RequestAndReply<IndexedRenameRequest>:
+      await self.handleRequest(for: request, requestHandler: self.indexedRename)
     // IMPORTANT: When adding a new entry to this switch, also add it to the `TaskMetadata` initializer.
     default:
       await request.reply { throw ResponseError.methodNotFound(R.method) }

Sources/SourceKitLSP/Swift/SwiftLanguageServer.swift

@@ -812,6 +812,10 @@ extension SwiftLanguageServer {
     }
   }
 
+  public func indexedRename(_ request: IndexedRenameRequest) async throws -> WorkspaceEdit? {
+    throw ResponseError.unknown("unsupported method")
+  }
+
   public func executeCommand(_ req: ExecuteCommandRequest) async throws -> LSPAny? {
     // TODO: If there's support for several types of commands, we might need to structure this similarly to the code actions request.
     guard let sourceKitServer else {

Sources/SourceKitLSP/ToolchainLanguageServer.swift

@@ -165,6 +165,8 @@ public protocol ToolchainLanguageServer: AnyObject {
   /// Return compound decl name that will be used as a placeholder for a rename request at a specific position.
   func prepareRename(_ request: PrepareRenameRequest) async throws -> PrepareRenameResponse?
 
+  func indexedRename(_ request: IndexedRenameRequest) async throws -> WorkspaceEdit?
+
   // MARK: - Other
 
   func executeCommand(_ req: ExecuteCommandRequest) async throws -> LSPAny?