EnvUtil for parallel sweep

Author: luke-gruber

tool/lib/envutil.rb

@@ -243,7 +243,7 @@ def invoke_ruby(args, stdin_data = "", capture_stdout = false, capture_stderr =
     # enable parallel sweep if current ruby has it enabled
     if (current_parallel_sweep? and
         args.none? { |arg| arg =~ /--disable[-=]parallel[-_]sweep/ } and
-        /^ +parallel-sweep/ =~ (rubybin_help ||= IO.popen([rubybin, "--help"], &:read)))
+        /^ +parallel-sweep/i =~ (rubybin_help ||= IO.popen([rubybin, "--help"], &:read)))
       args = ["--enable-parallel-sweep"] + args
     end
     pid = spawn(child_env, *precommand, rubybin, *args, opt)
@@ -293,14 +293,16 @@ def invoke_ruby(args, stdin_data = "", capture_stdout = false, capture_stderr =
   end
   module_function :invoke_ruby
 
+  RUBY_DESC_FEATURES_PAT = %r{\)\K [-+*/%._0-9a-zA-Z\[\] ]*(?=\[[-+*/%._0-9a-zA-Z]+\]\z)}
+
   def current_parser
-    features = RUBY_DESCRIPTION[%r{\)\K [-+*/%._0-9a-zA-Z\[\] ]*(?=\[[-+*/%._0-9a-zA-Z]+\]\z)}]
+    features = RUBY_DESCRIPTION[RUBY_DESC_FEATURES_PAT]
     features&.split&.include?("+PRISM") ? "prism" : "parse.y"
   end
   module_function :current_parser
 
   def current_parallel_sweep?
-    features = RUBY_DESCRIPTION[%r{\)\K [-+*/%._0-9a-zA-Z\[\] ]*(?=\[[-+*/%._0-9a-zA-Z]+\]\z)}]
+    features = RUBY_DESCRIPTION[RUBY_DESC_FEATURES_PAT]
     features&.split&.include?("+Parallel-Sweep")
   end
   module_function :current_parallel_sweep?