run rubocop on LSP process

Author: joe-re

language_server.gemspec

@@ -36,4 +36,5 @@ Gem::Specification.new do |spec|
   spec.add_development_dependency "m"
   spec.add_development_dependency "awesome_print"
   spec.add_development_dependency "benchmark-ips"
+  spec.add_development_dependency "rubocop"
 end

lib/language_server/linter/rubocop.rb

@@ -1,4 +1,7 @@
-require "open3"
+begin
+  require 'rubocop'
+rescue LoadError
+end
 
 module LanguageServer
   module Linter
@@ -8,17 +11,28 @@ def initialize(path, config_path="")
         @config_path = config_path
       end
 
+
       def call
-        Bundler.with_clean_env do
-          command = "rubocop #{@path} --format json --force-exclusion"
-          command += " --config #{@config_path}" if @config_path != ""
-          o, err, _ = Open3.capture3(command)
-          return [Error.new(line_num: 0, message: err, type: 'error')] if err != ""
-          JSON
-            .parse(o)['files'].map { |v| v['offenses'] }
-            .flatten
-            .map { |v| Error.new(line_num: v['location']['line'].to_i - 1, message: v['message'], type: convert_type(v['severity'])) }
+        return [] unless defined? ::RuboCop
+        args = ["--format", "json", @path]
+        args += ["--config", @config_path] if @config_path != ''
+        options, paths = ::RuboCop::Options.new.parse(args)
+        config_store = ::RuboCop::ConfigStore.new
+        config_store.options_config = options[:config] if options[:config]
+        o = nil
+        begin
+          $stdout = StringIO.new
+          runner = ::RuboCop::Runner.new(options, config_store)
+          runner.run(paths)
+          o = $stdout.string
+        ensure
+          $stdout = STDOUT
         end
+        return [] unless o
+        JSON
+          .parse(o)['files'].map { |v| v['offenses'] }
+          .flatten
+          .map { |v| Error.new(line_num: v['location']['line'].to_i - 1, message: v['message'], type: convert_type(v['severity'])) }
       end
 
       private