Use unique IDs for registering watchers

lib/ruby_lsp/internal.rb

@@ -23,6 +23,7 @@
 require "rbs"
 require "fileutils"
 require "open3"
+require "securerandom"
 
 require "ruby-lsp"
 require "ruby_lsp/base_server"

lib/ruby_lsp/server.rb

@@ -301,10 +301,19 @@ def run_initialize(message)
 
       # Not every client supports dynamic registration or file watching
       if @global_state.client_capabilities.supports_watching_files
-        send_message(Request.register_watched_files(@current_request_id, "**/*.rb"))
         send_message(Request.register_watched_files(
           @current_request_id,
-          Interface::RelativePattern.new(base_uri: @global_state.workspace_uri.to_s, pattern: ".rubocop.yml"),
+          "**/*.rb",
+          registration_id: "workspace-watcher",
+        ))
+
+        send_message(Request.register_watched_files(
+          @current_request_id,
+          Interface::RelativePattern.new(
+            base_uri: @global_state.workspace_uri.to_s,
+            pattern: "{.rubocop.yml,.rubocop}",
+          ),
+          registration_id: "rubocop-watcher",
         ))
       end
 
@@ -999,6 +1008,11 @@ def text_document_definition(message)
     sig { params(message: T::Hash[Symbol, T.untyped]).void }
     def workspace_did_change_watched_files(message)
       changes = message.dig(:params, :changes)
+      # We allow add-ons to register for watching files and we have no restrictions for what they register for. If the
+      # same pattern is registered more than once, the LSP will receive duplicate change notifications. Receiving them
+      # is fine, but we shouldn't process the same file changes more than once
+      changes.uniq!
+
       index = @global_state.index
       changes.each do |change|
         # File change events include folders, but we're only interested in files

lib/ruby_lsp/utils.rb

@@ -176,19 +176,27 @@ class Request < Message
     class << self
       extend T::Sig
 
-      sig { params(id: Integer, pattern: T.any(Interface::RelativePattern, String), kind: Integer).returns(Request) }
+      sig do
+        params(
+          id: Integer,
+          pattern: T.any(Interface::RelativePattern, String),
+          kind: Integer,
+          registration_id: T.nilable(String),
+        ).returns(Request)
+      end
       def register_watched_files(
         id,
         pattern,
-        kind: Constant::WatchKind::CREATE | Constant::WatchKind::CHANGE | Constant::WatchKind::DELETE
+        kind: Constant::WatchKind::CREATE | Constant::WatchKind::CHANGE | Constant::WatchKind::DELETE,
+        registration_id: nil
       )
         new(
           id: id,
           method: "client/registerCapability",
           params: Interface::RegistrationParams.new(
             registrations: [
               Interface::Registration.new(
-                id: "workspace/didChangeWatchedFiles",
+                id: registration_id || SecureRandom.uuid,
                 method: "workspace/didChangeWatchedFiles",
                 register_options: Interface::DidChangeWatchedFilesRegistrationOptions.new(
                   watchers: [

test/server_test.rb

@@ -521,6 +521,25 @@ def test_did_change_watched_files_does_not_fail_for_non_existing_files
     end
   end
 
+  def test_did_change_watched_files_processes_unique_change_entries
+    @server.expects(:handle_rubocop_config_change).once
+    @server.process_message({
+      method: "workspace/didChangeWatchedFiles",
+      params: {
+        changes: [
+          {
+            uri: URI::Generic.from_path(path: File.join(Dir.pwd, ".rubocop.yml")).to_s,
+            type: RubyLsp::Constant::FileChangeType::CHANGED,
+          },
+          {
+            uri: URI::Generic.from_path(path: File.join(Dir.pwd, ".rubocop.yml")).to_s,
+            type: RubyLsp::Constant::FileChangeType::CHANGED,
+          },
+        ],
+      },
+    })
+  end
+
   def test_workspace_addons
     create_test_addons
     @server.load_addons