Enable Start/EndWith and RegexpMatch cops

In cases where the MatchData object is not used, this provides a speed-up:
https://github.com/JuanitoFatas/fast-ruby/#stringmatch-vs-stringmatch-vs-stringstart_withstringend_with-code-start-code-end

.rubocop.yml

@@ -193,3 +193,12 @@ Performance/FlatMap:
 
 Performance/RedundantMerge:
   Enabled: true
+
+Performance/StartWith:
+  Enabled: true
+
+Performance/EndWith:
+  Enabled: true
+
+Performance/RegexpMatch:
+  Enabled: true

actioncable/Rakefile

@@ -57,7 +57,7 @@ namespace :assets do
     end
 
     print "[verify] #{file} is a UMD module "
-    if pathname.read =~ /module\.exports.*define\.amd/m
+    if /module\.exports.*define\.amd/m.match?(pathname.read)
       puts "[OK]"
     else
       $stderr.puts "[FAIL]"

actionpack/lib/abstract_controller/helpers.rb

@@ -17,7 +17,7 @@ module AbstractController
         @path  = "helpers/#{path}.rb"
         set_backtrace error.backtrace
 
-        if error.path =~ /^#{path}(\.rb)?$/
+        if /^#{path}(\.rb)?$/.match?(error.path)
           super("Missing helper file helpers/%s.rb" % path)
         else
           raise error

actionpack/lib/action_dispatch/http/headers.rb

@@ -121,7 +121,7 @@ module ActionDispatch
         # not contained within the headers hash.
         def env_name(key)
           key = key.to_s
-          if key =~ HTTP_HEADER
+          if HTTP_HEADER.match?(key)
             key = key.upcase.tr("-", "_")
             key = "HTTP_" + key unless CGI_VARIABLES.include?(key)
           end

actionpack/lib/action_dispatch/middleware/ssl.rb

@@ -113,7 +113,7 @@ module ActionDispatch
           cookies = cookies.split("\n".freeze)
 
           headers["Set-Cookie".freeze] = cookies.map { |cookie|
-            if cookie !~ /;\s*secure\s*(;|$)/i
+            if !/;\s*secure\s*(;|$)/i.match?(cookie)
               "#{cookie}; secure"
             else
               cookie

actionpack/lib/action_dispatch/routing/mapper.rb

@@ -279,7 +279,7 @@ module ActionDispatch
 
           def verify_regexp_requirements(requirements)
             requirements.each do |requirement|
-              if requirement.source =~ ANCHOR_CHARACTERS_REGEX
+              if ANCHOR_CHARACTERS_REGEX.match?(requirement.source)
                 raise ArgumentError, "Regexp anchor characters are not allowed in routing requirements: #{requirement.inspect}"
               end
 
@@ -333,7 +333,7 @@ module ActionDispatch
           end
 
           def split_to(to)
-            if to =~ /#/
+            if /#/.match?(to)
               to.split("#")
             else
               []
@@ -342,7 +342,7 @@ module ActionDispatch
 
           def add_controller_module(controller, modyoule)
             if modyoule && !controller.is_a?(Regexp)
-              if controller =~ %r{\A/}
+              if %r{\A/}.match?(controller)
                 controller[1..-1]
               else
                 [modyoule, controller].compact.join("/")
@@ -1588,7 +1588,7 @@ module ActionDispatch
             when Symbol
               options[:action] = to
             when String
-              if to =~ /#/
+              if /#/.match?(to)
                 options[:to] = to
               else
                 options[:controller] = to
@@ -1914,7 +1914,7 @@ module ActionDispatch
 
             default_action = options.delete(:action) || @scope[:action]
 
-            if action =~ /^[\w\-\/]+$/
+            if /^[\w\-\/]+$/.match?(action)
               default_action ||= action.tr("-", "_") unless action.include?("/")
             else
               action = nil

actionpack/lib/action_dispatch/testing/assertions/routing.rb

@@ -78,7 +78,7 @@ module ActionDispatch
       #   # Asserts that the generated route gives us our custom route
       #   assert_generates "changesets/12", { controller: 'scm', action: 'show_diff', revision: "12" }
       def assert_generates(expected_path, options, defaults = {}, extras = {}, message = nil)
-        if expected_path =~ %r{://}
+        if %r{://}.match?(expected_path)
           fail_on(URI::InvalidURIError, message) do
             uri = URI.parse(expected_path)
             expected_path = uri.path.to_s.empty? ? "/" : uri.path
@@ -189,7 +189,7 @@ module ActionDispatch
 
           request = ActionController::TestRequest.create @controller.class
 
-          if path =~ %r{://}
+          if %r{://}.match?(path)
             fail_on(URI::InvalidURIError, msg) do
               uri = URI.parse(path)
               request.env["rack.url_scheme"] = uri.scheme || "http"

actionpack/lib/action_dispatch/testing/integration.rb

@@ -217,7 +217,7 @@ module ActionDispatch
           method = :post
         end
 
-        if path =~ %r{://}
+        if %r{://}.match?(path)
           path = build_expanded_path(path) do |location|
             https! URI::HTTPS === location if location.scheme
 

actionview/Rakefile

@@ -107,7 +107,7 @@ namespace :assets do
     end
 
     print "[verify] #{file} is a UMD module "
-    if pathname.read =~ /module\.exports.*define\.amd/m
+    if /module\.exports.*define\.amd/m.match?(pathname.read)
       puts "[OK]"
     else
       $stderr.puts "[FAIL]"

actionview/lib/action_view/helpers/tags/color_field.rb

@@ -15,7 +15,7 @@ module ActionView
 
           def validate_color_string(string)
             regex = /#[0-9a-fA-F]{6}/
-            if regex.match(string)
+            if regex.match?(string)
               string.downcase
             else
               "#000000"

actionview/lib/action_view/helpers/text_helper.rb

@@ -188,7 +188,7 @@ module ActionView
 
         unless separator.empty?
           text.split(separator).each do |value|
-            if value.match(regex)
+            if value.match?(regex)
               phrase = value
               break
             end

activerecord/lib/active_record/connection_adapters/abstract_adapter.rb

@@ -81,7 +81,7 @@ module ActiveRecord
       alias :in_use? :owner
 
       def self.type_cast_config_to_integer(config)
-        if config =~ SIMPLE_INT
+        if SIMPLE_INT.match?(config)
           config.to_i
         else
           config

activerecord/lib/active_record/relation/calculations.rb

@@ -245,7 +245,7 @@ module ActiveRecord
             if distinct && (group_values.any? || select_values.empty? && order_values.empty?)
               column_name = primary_key
             end
-          elsif column_name =~ /\s*DISTINCT[\s(]+/i
+          elsif /\s*DISTINCT[\s(]+/i.match?(column_name)
             distinct = nil
           end
         end

guides/Rakefile

@@ -30,7 +30,7 @@ namespace :guides do
       unless Kindlerb.kindlegen_available?
         abort "Please run `setupkindlerb` to install kindlegen"
       end
-      unless `convert` =~ /convert/
+      unless /convert/.match?(`convert`)
         abort "Please install ImageMagick"
       end
       ENV["KINDLE"] = "1"

guides/rails_guides/kindle.rb

@@ -35,7 +35,7 @@ module Kindle
   def generate_front_matter(html_pages)
     frontmatter = []
     html_pages.delete_if { |x|
-      if x =~ /(toc|welcome|copyright).html/
+      if /(toc|welcome|copyright).html/.match?(x)
         frontmatter << x unless x =~ /toc/
         true
       end

guides/rails_guides/markdown.rb

@@ -69,7 +69,7 @@ module RailsGuides
       end
 
       def extract_raw_header_and_body
-        if @raw_body =~ /^\-{40,}$/
+        if /^\-{40,}$/.match?(@raw_body)
           @raw_header, _, @raw_body = @raw_body.partition(/^\-{40,}$/).map(&:strip)
         end
       end
@@ -89,7 +89,7 @@ module RailsGuides
             hierarchy = []
 
             doc.children.each do |node|
-              if node.name =~ /^h[3-6]$/
+              if /^h[3-6]$/.match?(node.name)
                 case node.name
                 when "h3"
                   hierarchy = [node]

guides/rails_guides/markdown/renderer.rb

@@ -35,7 +35,7 @@ HTML
       def paragraph(text)
         if text =~ %r{^NOTE:\s+Defined\s+in\s+<code>(.*?)</code>\.?$}
           %(<div class="note"><p>Defined in <code><a href="#{github_file_url($1)}">#{$1}</a></code>.</p></div>)
-        elsif text =~ /^(TIP|IMPORTANT|CAUTION|WARNING|NOTE|INFO|TODO)[.:]/
+        elsif /^(TIP|IMPORTANT|CAUTION|WARNING|NOTE|INFO|TODO)[.:]/.match?(text)
           convert_notes(text)
         elsif text.include?("DO NOT READ THIS FILE ON GITHUB")
         elsif text =~ /^\[<sup>(\d+)\]:<\/sup> (.+)$/
@@ -110,7 +110,7 @@ HTML
         end
 
         def api_link(url)
-          if url =~ %r{http://api\.rubyonrails\.org/v\d+\.}
+          if %r{http://api\.rubyonrails\.org/v\d+\.}.match?(url)
             url
           elsif edge
             url.sub("api", "edgeapi")

railties/lib/rails/app_loader.rb

@@ -49,7 +49,7 @@ EOS
         if exe = find_executable
           contents = File.read(exe)
 
-          if contents =~ /(APP|ENGINE)_PATH/
+          if /(APP|ENGINE)_PATH/.match?(contents)
             exec RUBY, exe, *ARGV
             break # non reachable, hack to be able to stub exec in the test suite
           elsif exe.end_with?("bin/rails") && contents.include?("This file was generated by Bundler")

railties/lib/rails/code_statistics.rb

@@ -46,7 +46,7 @@ class CodeStatistics #:nodoc:
 
         if File.directory?(path) && (/^\./ !~ file_name)
           stats.add(calculate_directory_statistics(path, pattern))
-        elsif file_name =~ pattern
+        elsif file_name&.match?(pattern)
           stats.add_by_file_path(path)
         end
       end

railties/lib/rails/commands/secrets/secrets_command.rb

@@ -42,7 +42,7 @@ module Rails
       rescue Rails::Secrets::MissingKeyError => error
         say error.message
       rescue Errno::ENOENT => error
-        if error.message =~ /secrets\.yml\.enc/
+        if /secrets\.yml\.enc/.match?(error.message)
           deprecate_in_favor_of_credentials_and_exit
         else
           raise

railties/lib/rails/generators/app_base.rb

@@ -376,7 +376,7 @@ module Rails
         comment = "See https://github.com/rails/execjs#readme for more supported runtimes"
         if defined?(JRUBY_VERSION)
           GemfileEntry.version "therubyrhino", nil, comment
-        elsif RUBY_PLATFORM =~ /mingw|mswin/
+        elsif RUBY_PLATFORM.match?(/mingw|mswin/)
           GemfileEntry.version "duktape", nil, comment
         else
           GemfileEntry.new "mini_racer", nil, comment, { platforms: :ruby }, true

railties/lib/rails/generators/rails/app/app_generator.rb

@@ -515,7 +515,7 @@ module Rails
       end
 
       def valid_const?
-        if app_const =~ /^\d/
+        if /^\d/.match?(app_const)
           raise Error, "Invalid application name #{original_app_name}. Please give a name which does not start with numbers."
         elsif RESERVED_NAMES.include?(original_app_name)
           raise Error, "Invalid application name #{original_app_name}. Please give a " \

railties/lib/rails/generators/rails/plugin/plugin_generator.rb

@@ -385,11 +385,11 @@ task default: :test
       end
 
       def valid_const?
-        if original_name =~ /-\d/
+        if /-\d/.match?(original_name)
           raise Error, "Invalid plugin name #{original_name}. Please give a name which does not contain a namespace starting with numeric characters."
-        elsif original_name =~ /[^\w-]+/
+        elsif /[^\w-]+/.match?(original_name)
           raise Error, "Invalid plugin name #{original_name}. Please give a name which uses only alphabetic, numeric, \"_\" or \"-\" characters."
-        elsif camelized =~ /^\d/
+        elsif /^\d/.match?(camelized)
           raise Error, "Invalid plugin name #{original_name}. Please give a name which does not start with numbers."
         elsif RESERVED_NAMES.include?(name)
           raise Error, "Invalid plugin name #{original_name}. Please give a " \

railties/lib/rails/test_unit/runner.rb

@@ -63,7 +63,7 @@ module Rails
             # Extract absolute and relative paths but skip -n /.*/ regexp filters.
             argv.select { |arg| arg =~ %r%^/?\w+/% && !arg.end_with?("/") }.map do |path|
               case
-              when path =~ /(:\d+)+$/
+              when /(:\d+)+$/.match?(path)
                 file, *lines = path.split(":")
                 filters << [ file, lines ]
                 file

tasks/release.rb

@@ -89,7 +89,7 @@ npm_version = version.gsub(/\./).with_index { |s, i| i >= 2 ? "-" : s }
 
       if File.exist?("#{framework}/package.json")
         Dir.chdir("#{framework}") do
-          npm_tag = version =~ /[a-z]/ ? "pre" : "latest"
+          npm_tag = /[a-z]/.match?(version) ? "pre" : "latest"
           sh "npm publish --tag #{npm_tag}"
         end
       end