chore: switch from parser to prism

Parser is being softly deprecated. See
whitequark/parser#1046

Author: BuonOmo

Gemfile

@@ -60,6 +60,7 @@ group :development, :test do
 
   # Gems used for tests meta-programming.
   gem "parser"
+  gem "prism" # Parser is being softly deprecated, but Prism doesn't have rewriting capabilities
 
   # Gems used by the ActiveRecord test suite
   gem "bcrypt", "~> 3.1"

test/support/copy_cat.rb

@@ -1,6 +1,7 @@
 # frozen_string_literal: true
 
-require "parser/current"
+require "parser"
+require "prism"
 
 module CopyCat
   module NoWarnRewrite
@@ -23,13 +24,13 @@ def warn(message, category: nil, **kwargs)
   def copy_methods(new_klass, old_klass, *methods, debug: false, &block)
     methods.each do |met|
       file, _ = old_klass.instance_method(met).source_location
-      ast = find_method(Parser::CurrentRuby.parse_file(file), met)
+      ast = find_method(Prism::Translation::Parser.parse_file(file), met)
       code =
         if block_given?
           source = ast.location.expression.source
           buffer = Parser::Source::Buffer.new(met, source: source)
           # We need to recompute the ast to have correct locations.
-          ast = Parser::CurrentRuby.parse(source)
+          ast = Prism::Translation::Parser.parse(source)
 
           if debug
             puts "=" * 80