Simplify and allow to configure rubocop formatter

lib/solargraph/diagnostics/rubocop_helpers.rb

@@ -13,32 +13,13 @@ module RubocopHelpers
       # @param code [String]
       # @return [Array(Array<String>, Array<String>)]
       def generate_options filename, code
-        args = ['-f', 'j']
-        rubocop_file = find_rubocop_file(filename)
-        args.push('-c', fix_drive_letter(rubocop_file)) unless rubocop_file.nil?
-        args.push filename
+        args = ['-f', 'j', filename]
         base_options = RuboCop::Options.new
         options, paths = base_options.parse(args)
         options[:stdin] = code
         [options, paths]
       end
 
-      # Find a RuboCop configuration file in a file's directory tree.
-      #
-      # @param filename [String]
-      # @return [String, nil]
-      def find_rubocop_file filename
-        return nil unless File.exist?(filename)
-        filename = File.realpath(filename)
-        dir = File.dirname(filename)
-        until File.dirname(dir) == dir
-          here = File.join(dir, '.rubocop.yml')
-          return here if File.exist?(here)
-          dir = File.dirname(dir)
-        end
-        nil
-      end
-
       # RuboCop internally uses capitalized drive letters for Windows paths,
       # so we need to convert the paths provided to the command.
       #

lib/solargraph/language_server/host.rb

@@ -494,6 +494,11 @@ def read_text uri
         library.read_text(filename)
       end
 
+      def formatter_config uri
+        library = library_for(uri)
+        library.workspace.config.formatter
+      end
+
       # @param uri [String]
       # @param line [Integer]
       # @param column [Integer]

lib/solargraph/language_server/message/text_document/formatting.rb

@@ -11,29 +11,58 @@ module TextDocument
         class Formatting < Base
           include Solargraph::Diagnostics::RubocopHelpers
 
+          class BlankRubocopFormatter < ::RuboCop::Formatter::BaseFormatter; end
+
           def process
-            filename = uri_to_file(params['textDocument']['uri'])
-            Dir.mktmpdir do |tempdir|
-              tempfile = File.join(tempdir, File.basename(filename))
-              rubocop_file = Diagnostics::RubocopHelpers.find_rubocop_file(filename)
-              original = host.read_text(params['textDocument']['uri'])
-              File.write tempfile, original
-              begin
-                args = ['-a', '-f', 'fi', tempfile]
-                args.unshift('-c', fix_drive_letter(rubocop_file)) unless rubocop_file.nil?
-                options, paths = RuboCop::Options.new.parse(args)
-                store = RuboCop::ConfigStore.new
-                redirect_stdout { RuboCop::Runner.new(options, store).run(paths) }
-                result = File.read(tempfile)
-                format original, result
-              rescue RuboCop::ValidationError, RuboCop::ConfigNotFoundError => e
-                set_error(Solargraph::LanguageServer::ErrorCodes::INTERNAL_ERROR, "[#{e.class}] #{e.message}")
-              end
+            file_uri = params['textDocument']['uri']
+            config = config_for(file_uri)
+            original = host.read_text(file_uri)
+            args = cli_args(file_uri, config)
+
+            options, paths = RuboCop::Options.new.parse(args)
+            options[:stdin] = original
+            redirect_stdout do
+              RuboCop::Runner.new(options, RuboCop::ConfigStore.new).run(paths)
             end
+            result = options[:stdin]
+
+            format original, result
+          rescue RuboCop::ValidationError, RuboCop::ConfigNotFoundError => e
+            set_error(Solargraph::LanguageServer::ErrorCodes::INTERNAL_ERROR, "[#{e.class}] #{e.message}")
           end
 
           private
 
+          def config_for(file_uri)
+            conf = host.formatter_config(file_uri)
+            return {} unless conf.is_a?(Hash)
+
+            conf['rubocop'] || {}
+          end
+
+          def cli_args file, config
+            args = [
+              config['cops'] == 'all' ? '--auto-correct-all' : '--auto-correct',
+              '--cache', 'false',
+              '--format', 'Solargraph::LanguageServer::Message::' \
+                          'TextDocument::Formatting::BlankRubocopFormatter',
+            ]
+
+            ['except', 'only'].each do |arg|
+              cops = cop_list(config[arg])
+              args += ["--#{arg}", cops] if cops
+            end
+
+            args += config['extra_args'] if config['extra_args']
+            args + [file]
+          end
+
+          def cop_list(value)
+            value = value.join(',') if value.respond_to?(:join)
+            return nil if value == '' || !value.is_a?(String)
+            value
+          end
+
           # @param original [String]
           # @param result [String]
           # @return [void]

lib/solargraph/workspace/config.rb

@@ -85,6 +85,13 @@ def reporters
         raw_data['reporters']
       end
 
+      # A hash of options supported by the formatter
+      #
+      # @return [Hash]
+      def formatter
+        raw_data['formatter']
+      end
+
       # An array of plugins to require.
       #
       # @return [Array<String>]
@@ -144,6 +151,14 @@ def default_config
           'require' => [],
           'domains' => [],
           'reporters' => %w[rubocop require_not_found],
+          'formatter' => {
+            'rubocop' => {
+              'cops' => 'safe',
+              'except' => [],
+              'only' => [],
+              'extra_args' =>[]
+            }
+          },
           'require_paths' => [],
           'plugins' => [],
           'max_files' => MAX_FILES

spec/diagnostics/rubocop_helpers_spec.rb

@@ -1,11 +1,4 @@
 describe Solargraph::Diagnostics::RubocopHelpers do
-  it "finds a .rubocop.yml file in a parent directory" do
-    file = File.realpath(File.join 'spec', 'fixtures', 'rubocop-subfolder-configuration', 'folder1', 'folder2', 'test.rb')
-    conf = File.realpath(File.join 'spec', 'fixtures', 'rubocop-subfolder-configuration', '.rubocop.yml')
-    found = Solargraph::Diagnostics::RubocopHelpers.find_rubocop_file(file)
-    expect(found).to eq(conf)
-  end
-
   it "converts lower-case drive letters to upper-case" do
     input = 'c:/one/two'
     output = Solargraph::Diagnostics::RubocopHelpers.fix_drive_letter(input)

spec/language_server/message/text_document/formatting_spec.rb

@@ -1,6 +1,6 @@
 describe Solargraph::LanguageServer::Message::TextDocument::Formatting do
   it 'gracefully handles empty files' do
-    host = double(:Host, read_text: '')
+    host = double(:Host, read_text: '', formatter_config: {})
     request = {
       'params' => {
           'textDocument' => {