Make specs use the generated metagrammar.rb so debugging the parser i…

…s easier and so there's never a mismatch between the parser that gets tested (via eval) and the parser that gets packaged (metagrammar.rb)

(cherry picked from commit d6ab4c3)

spec/compiler/character_class_spec.rb

@@ -1,4 +1,4 @@
-require File.join(File.dirname(__FILE__), '..', 'spec_helper')
+require File.expand_path("#{File.dirname(__FILE__)}/../spec_helper")
 
 module CharacterClassSpec
   class Foo < Treetop::Runtime::SyntaxNode

spec/compiler/circular_compilation_spec.rb

@@ -1,5 +1,6 @@
 require File.expand_path("#{File.dirname(__FILE__)}/../spec_helper")
 BENCHMARK = false
+METAGRAMMAR_PATH = File.join(TREETOP_ROOT, 'compiler', 'metagrammar.treetop')
 
 module CircularCompilationSpec
   describe "a parser for the metagrammar" do

spec/spec_helper.rb

@@ -3,9 +3,7 @@
 require 'benchmark'
 require 'spec'
 
-unless $bootstrapped_gen_1_metagrammar
-  load File.join(dir, '..', 'lib', 'treetop', 'bootstrap_gen_1_metagrammar.rb')
-end
+require File.join(dir, '..', 'lib', 'treetop')
 include Treetop
 
 Spec::Runner.configure do |config|