Enable reusable Prism parse result for Ruby LSP add-on

Follow-up to Shopify/ruby-lsp#1849

This feature utilizes ruby/prism#3478 and rubocop/rubocop-ast#359
to implement Shopify/ruby-lsp#1849.

As described in rubocop/rubocop-ast#359,
it speeds up the processing around `Prism::Translation::Parser` via `ProcessedSource` by 1.3x when using the Ruby LSP add-on.

Author: koic

changelog/new_enable_reusable_prism_parse_results_for_ruby_lsp_addon.md

@@ -0,0 +1 @@
+* [#13899](https://github.com/rubocop/rubocop/pull/13899): Enable reusable Prism parse result for Ruby LSP add-on. ([@koic][])

lib/rubocop/lsp/runtime.rb

@@ -30,7 +30,7 @@ def initialize(config_store)
         @layout_mode = false
       end
 
-      def format(path, text, command:)
+      def format(path, text, command:, prism_result: nil)
         safe_autocorrect = if command
                              command == 'rubocop.formatAutocorrects'
                            else
@@ -40,15 +40,15 @@ def format(path, text, command:)
         formatting_options = { autocorrect: true, safe_autocorrect: safe_autocorrect }
         formatting_options[:only] = config_only_options if @lint_mode || @layout_mode
 
-        @runner.run(path, text, formatting_options)
+        @runner.run(path, text, formatting_options, prism_result: prism_result)
         @runner.formatted_source
       end
 
-      def offenses(path, text, document_encoding = nil)
+      def offenses(path, text, document_encoding = nil, prism_result: nil)
         diagnostic_options = {}
         diagnostic_options[:only] = config_only_options if @lint_mode || @layout_mode
 
-        @runner.run(path, text, diagnostic_options)
+        @runner.run(path, text, diagnostic_options, prism_result: prism_result)
         @runner.offenses.map do |offense|
           Diagnostic.new(
             document_encoding, offense, path, @cop_registry[offense.cop_name]&.first

lib/rubocop/lsp/stdin_runner.rb

@@ -41,10 +41,12 @@ def initialize(config_store)
       end
 
       # rubocop:disable Metrics/MethodLength
-      def run(path, contents, options)
+      def run(path, contents, options, prism_result: nil)
         @options = options.merge(DEFAULT_RUBOCOP_OPTIONS)
         @options[:stdin] = contents
 
+        @prism_result = prism_result
+
         @offenses = []
         @warnings = []
         @errors = []

lib/rubocop/runner.rb

@@ -489,7 +489,11 @@ def get_processed_source(file)
 
       processed_source = if @options[:stdin]
                            ProcessedSource.new(
-                             @options[:stdin], ruby_version, file, parser_engine: parser_engine
+                             @options[:stdin],
+                             ruby_version,
+                             file,
+                             parser_engine: parser_engine,
+                             prism_result: @prism_result
                            )
                          else
                            begin

lib/ruby_lsp/rubocop/runtime_adapter.rb

@@ -16,11 +16,21 @@ def initialize
       end
 
       def run_diagnostic(uri, document)
-        @runtime.offenses(uri_to_path(uri), document.source, document.encoding)
+        @runtime.offenses(
+          uri_to_path(uri),
+          document.source,
+          document.encoding,
+          prism_result: prism_result(document)
+        )
       end
 
       def run_formatting(uri, document)
-        @runtime.format(uri_to_path(uri), document.source, command: 'rubocop.formatAutocorrects')
+        @runtime.format(
+          uri_to_path(uri),
+          document.source,
+          command: 'rubocop.formatAutocorrects',
+          prism_result: prism_result(document)
+        )
       end
 
       def run_range_formatting(_uri, _partial_source, _base_indentation)
@@ -42,6 +52,14 @@ def uri_to_path(uri)
           uri.to_s.delete_prefix('file://')
         end
       end
+
+      def prism_result(document)
+        prism_result = document.parse_result
+
+        # NOTE: `prism_result` must be `Prism::ParseLexResult` compatible object.
+        # This is for compatibility parsed result unsupported.
+        prism_result.is_a?(Prism::ParseLexResult) ? prism_result : nil
+      end
     end
   end
 end

rubocop.gemspec

@@ -40,7 +40,7 @@ Gem::Specification.new do |s|
   s.add_dependency('parser', '>= 3.3.0.2')
   s.add_dependency('rainbow', '>= 2.2.2', '< 4.0')
   s.add_dependency('regexp_parser', '>= 2.9.3', '< 3.0')
-  s.add_dependency('rubocop-ast', '>= 1.38.0', '< 2.0')
+  s.add_dependency('rubocop-ast', '>= 1.39.0', '< 2.0')
   s.add_dependency('ruby-progressbar', '~> 1.7')
   s.add_dependency('unicode-display_width', '>= 2.4.0', '< 4.0')
 end