Request diagnostic refresh when RuboCop configs change

lib/ruby_lsp/client_capabilities.rb

@@ -11,7 +11,8 @@ class ClientCapabilities
     attr_reader :supports_watching_files,
       :supports_request_delegation,
       :window_show_message_supports_extra_properties,
-      :supports_progress
+      :supports_progress,
+      :supports_diagnostic_refresh
 
     sig { void }
     def initialize
@@ -32,6 +33,9 @@ def initialize
 
       # The editor supports displaying progress requests
       @supports_progress = T.let(false, T::Boolean)
+
+      # The editor supports server initiated refresh for diagnostics
+      @supports_diagnostic_refresh = T.let(false, T::Boolean)
     end
 
     sig { params(capabilities: T::Hash[Symbol, T.untyped]).void }
@@ -57,6 +61,8 @@ def apply_client_capabilities(capabilities)
 
       progress = capabilities.dig(:window, :workDoneProgress)
       @supports_progress = progress if progress
+
+      @supports_diagnostic_refresh = workspace_capabilities.dig(:diagnostics, :refreshSupport) || false
     end
 
     sig { returns(T::Boolean) }

lib/ruby_lsp/server.rb

@@ -1039,16 +1039,20 @@ def handle_ruby_file_change(index, file_path, change_type)
     def handle_rubocop_config_change(uri)
       return unless defined?(Requests::Support::RuboCopFormatter)
 
-      send_log_message("Reloading RuboCop since #{uri} changed")
+      # Register a new runner to reload configurations
       @global_state.register_formatter("rubocop", Requests::Support::RuboCopFormatter.new)
 
-      # Clear all existing diagnostics since the config changed. This has to happen under a mutex because the `state`
-      # hash cannot be mutated during iteration or that will throw an error
+      # Clear all document caches for pull diagnostics
       @global_state.synchronize do
-        @store.each do |uri, _document|
-          send_message(Notification.publish_diagnostics(uri.to_s, []))
+        @store.each do |_uri, document|
+          document.cache_set("textDocument/diagnostic", Document::EMPTY_CACHE)
         end
       end
+
+      # Request a pull diagnostic refresh from the editor
+      if @global_state.client_capabilities.supports_diagnostic_refresh
+        send_message(Request.new(id: @current_request_id, method: "workspace/diagnostic/refresh", params: nil))
+      end
     end
 
     sig { params(message: T::Hash[Symbol, T.untyped]).void }

lib/ruby_lsp/utils.rb

@@ -162,7 +162,9 @@ def publish_diagnostics(uri, diagnostics, version: nil)
 
     sig { override.returns(T::Hash[Symbol, T.untyped]) }
     def to_hash
-      { method: @method, params: T.unsafe(@params).to_hash }
+      hash = { method: @method }
+      hash[:params] = T.unsafe(@params).to_hash if @params
+      hash
     end
   end
 
@@ -206,7 +208,9 @@ def initialize(id:, method:, params:)
 
     sig { override.returns(T::Hash[Symbol, T.untyped]) }
     def to_hash
-      { id: @id, method: @method, params: T.unsafe(@params).to_hash }
+      hash = { id: @id, method: @method }
+      hash[:params] = T.unsafe(@params).to_hash if @params
+      hash
     end
   end
 

test/server_test.rb

@@ -995,6 +995,39 @@ def test_edits_outside_of_declarations_do_not_trigger_indexing
     assert_equal(1, entries.length)
   end
 
+  def test_rubocop_config_changes_trigger_workspace_diagnostic_refresh
+    uri = URI::Generic.from_path(path: File.join(Dir.pwd, ".rubocop.yml"))
+
+    @server.process_message({
+      id: 1,
+      method: "initialize",
+      params: {
+        initializationOptions: {},
+        capabilities: {
+          general: {
+            positionEncodings: ["utf-8"],
+          },
+          workspace: { diagnostics: { refreshSupport: true } },
+        },
+      },
+    })
+
+    @server.process_message({
+      method: "workspace/didChangeWatchedFiles",
+      params: {
+        changes: [
+          {
+            uri: uri,
+            type: RubyLsp::Constant::FileChangeType::CHANGED,
+          },
+        ],
+      },
+    })
+
+    request = find_message(RubyLsp::Request)
+    assert_equal("workspace/diagnostic/refresh", request.method)
+  end
+
   private
 
   def with_uninstalled_rubocop(&block)