version 0.3.0, some ruby 1.8 supportdev

7 files changed, 145 insertions, 74 deletions

diff --git a/README.markdown b/README.markdown
index bc42a82..bb1c83d 100644
--- a/README.markdown
+++ b/README.markdown
@@ -1,11 +1,11 @@
 method_source
 =============
 
-(C) John Mair (banisterfiend) 2010
+(C) John Mair (banisterfiend) 2011
 
 _retrieve the sourcecode for a method_
 
-*NOTE:* This simply utilizes `Method#source_location` in Ruby 1.9; it
+*NOTE:* This simply utilizes `Method#source_location`; it
  does not access the live AST.
 
 `method_source` is a utility to return a method's sourcecode as a
@@ -15,6 +15,8 @@ Method comments can also be extracted using the `comment` method.
 
 It is written in pure Ruby (no C).
 
+* Some Ruby 1.8 support now available. 
+
 `method_source` provides the `source` and `comment` methods to the `Method` and
 `UnboundMethod` and `Proc` classes.
 
@@ -48,19 +50,14 @@ Example: display method comments
 Limitations:
 ------------
 
-* Only works with Ruby 1.9+ 
+* Proc#source not available in Ruby 1.8
+* Occasional strange behaviour in Ruby 1.8
 * Cannot return source for C methods.
 * Cannot return source for dynamically defined methods.
 
-Possible Applications:
-----------------------
-
-* Combine with [RubyParser](https://github.com/seattlerb/ruby_parser)
-  for extra fun.
-
-
 Special Thanks
 --------------
 
 [Adam Sanderson](https://github.com/adamsanderson) for `comment` functionality.
 
+[Dmitry Elastic](https://github.com/dmitryelastic) for the brilliant Ruby 1.8 `source_location` hack.
diff --git a/Rakefile b/Rakefile
index 4edeaac..b24114d 100644
--- a/Rakefile
+++ b/Rakefile
@@ -19,10 +19,12 @@ def apply_spec_defaults(s)
   s.email = 'jrmair@gmail.com'
   s.description = s.summary
   s.require_path = 'lib'
+  s.add_dependency("ruby_parser",">=2.0.5")
+  s.add_development_dependency("bacon",">=1.1.0")
   s.homepage = "http://banisterfiend.wordpress.com"
   s.has_rdoc = 'yard'
   s.files = Dir["ext/**/extconf.rb", "ext/**/*.h", "ext/**/*.c", "lib/**/*.rb",
-                     "test/*.rb", "CHANGELOG", "README.markdown", "Rakefile"]
+                     "test/*.rb", "CHANGELOG", "README.markdown", "Rakefile", ".gemtest"]
 end
 
 task :test do
diff --git a/lib/method_source.rb b/lib/method_source.rb
index d6a6e29..43651b9 100644
--- a/lib/method_source.rb
+++ b/lib/method_source.rb
@@ -4,19 +4,41 @@
 direc = File.dirname(__FILE__)
 
 require "#{direc}/method_source/version"
-
-if RUBY_VERSION =~ /1.9/
-  require 'ripper'
-end
+require "#{direc}/method_source/source_location"
 
 module MethodSource
 
-  # Helper method used to find end of method body
-  # @param [String] code The string of Ruby code to check for
-  # correctness
-  # @return [Boolean] 
-  def self.valid_expression?(code)
-    !!Ripper::SexpBuilder.new(code).parse
+  if RUBY_VERSION =~ /1.9/
+    require 'ripper'
+
+    # Determine if a string of code is a valid Ruby expression.
+    # Ruby 1.9 uses Ripper, Ruby 1.8 uses RubyParser.
+    # @param [String] code The code to validate.
+    # @return [Boolean] Whether or not the code is a valid Ruby expression.
+    # @example
+    #   valid_expression?("class Hello") #=> false
+    #   valid_expression?("class Hello; end") #=> true
+    def self.valid_expression?(code)
+      !!Ripper::SexpBuilder.new(code).parse
+    end
+
+  else
+    require 'ruby_parser'
+
+    # Determine if a string of code is a valid Ruby expression.
+    # Ruby 1.9 uses Ripper, Ruby 1.8 uses RubyParser.
+    # @param [String] code The code to validate.
+    # @return [Boolean] Whether or not the code is a valid Ruby expression.
+    # @example
+    #   valid_expression?("class Hello") #=> false
+    #   valid_expression?("class Hello; end") #=> true
+    def self.valid_expression?(code)
+      RubyParser.new.parse(code)
+    rescue Racc::ParseError, SyntaxError
+      false
+    else
+      true
+    end
   end
 
   # Helper method responsible for extracting method body.
@@ -86,7 +108,7 @@ module MethodSource
         
         raise "Cannot locate source for this method: #{name}" if !source
       else
-        raise "Method#source not supported by this Ruby version (#{RUBY_VERSION})"
+        raise "#{self.class}#source not supported by this Ruby version (#{RUBY_VERSION})"
       end
       
       source
@@ -105,7 +127,7 @@ module MethodSource
         
         raise "Cannot locate source for this method: #{name}" if !comment
       else
-        raise "Method#comment not supported by this Ruby version (#{RUBY_VERSION})"
+        raise "#{self.class}#comment not supported by this Ruby version (#{RUBY_VERSION})"
       end
 
       comment
@@ -114,10 +136,12 @@ module MethodSource
 end
 
 class Method
+  include MethodSource::SourceLocation::MethodExtensions
   include MethodSource::MethodExtensions
 end
 
 class UnboundMethod
+  include MethodSource::SourceLocation::UnboundMethodExtensions
   include MethodSource::MethodExtensions
 end
 
diff --git a/lib/method_source/source_location.rb b/lib/method_source/source_location.rb
new file mode 100644
index 0000000..1878b18
--- /dev/null
+++ b/lib/method_source/source_location.rb
@@ -0,0 +1,56 @@
+module MethodSource
+  module SourceLocation
+    module MethodExtensions
+      def trace_func(event, file, line, id, binding, classname)
+        return unless event == 'call'
+        set_trace_func nil 
+        
+        @file, @line = file, line
+        raise :found
+      end
+      
+      # Return the source location of a method for Ruby 1.8.
+      # @return [Array] A two element array. First element is the
+      #   file, second element is the line in the file where the
+      #   method definition is found.
+      def source_location
+        if @file.nil?
+          args =[*(1..(arity<-1 ? -arity-1 : arity ))]
+          
+          set_trace_func method(:trace_func).to_proc
+          call *args rescue nil
+          set_trace_func nil 
+          @file = File.expand_path(@file) if @file && File.exist?(File.expand_path(@file))
+        end
+        return [@file, @line] if File.exist?(@file.to_s)
+      end
+    end
+
+    module UnboundMethodExtensions
+
+      # Return the source location of an instance method for Ruby 1.8.
+      # @return [Array] A two element array. First element is the
+      #   file, second element is the line in the file where the
+      #   method definition is found.
+      def source_location
+        klass = case owner
+                when Class
+                  owner
+                when Module
+                  Class.new.tap { |v| v.send(:include, owner) }
+                end
+
+        begin
+          klass.allocate.method(name).source_location
+        rescue TypeError
+
+          # Assume we are dealing with a Singleton Class:
+          # 1. Get the instance object
+          # 2. Forward the source_location lookup to the instance
+          instance ||= ObjectSpace.each_object(owner).first
+          instance.method(name).source_location
+        end
+      end
+    end
+  end
+end
diff --git a/lib/method_source/version.rb b/lib/method_source/version.rb
index 2ac241c..6a830a9 100644
--- a/lib/method_source/version.rb
+++ b/lib/method_source/version.rb
@@ -1,3 +1,3 @@
 module MethodSource
-  VERSION = "0.2.0"
+  VERSION = "0.3.0"
 end
diff --git a/test/test.rb b/test/test.rb
index 48f3ed8..8b84538 100644
--- a/test/test.rb
+++ b/test/test.rb
@@ -21,28 +21,21 @@ describe MethodSource do
   end
 
   describe "Methods" do
-    if RUBY_VERSION =~ /1.9/
-      it 'should return source for method' do
-        method(:hello).source.should == @hello_source
-      end
-      
-      it 'should return a comment for method' do
-        method(:hello).comment.should == @hello_comment
-      end
-
-      it 'should raise for C methods' do
-        lambda { method(:puts).source }.should.raise RuntimeError
-      end
+    it 'should return source for method' do
+      method(:hello).source.should == @hello_source
+    end
+    
+    it 'should return a comment for method' do
+      method(:hello).comment.should == @hello_comment
+    end
 
-    else
-      it 'should raise on #source for 1.8' do
-        lambda { method(:hello).source }.should.raise RuntimeError
-      end
+    it 'should raise for C methods' do
+      lambda { method(:puts).source }.should.raise RuntimeError
     end
   end
 
-  describe "Lambdas and Procs" do
-    if RUBY_VERSION =~ /1.9/
+  if RUBY_VERSION =~ /1.9/
+    describe "Lambdas and Procs" do
       it 'should return source for proc' do
         MyProc.source.should == @proc_source
       end
@@ -58,42 +51,35 @@ describe MethodSource do
       it 'should return comment for lambda' do
         MyLambda.comment.should == @lambda_comment
       end
-    else
-      it 'should raise on #source for 1.8' do
-        lambda { method(:hello).source }.should.raise RuntimeError
-      end
     end      
   end
+  describe "Comment tests" do
+    before do
+      @comment1 = "# a\n# b\n"
+      @comment2 = "# a\n# b\n"
+      @comment3 = "# a\n#\n# b\n"
+      @comment4 = "# a\n# b\n"
+      @comment5 = "# a\n# b\n# c\n# d\n"
+    end
 
-  if RUBY_VERSION =~ /1.9/
-    describe "Comment tests" do
-      before do
-        @comment1 = "# a\n# b\n"
-        @comment2 = "# a\n# b\n"
-        @comment3 = "# a\n#\n# b\n"
-        @comment4 = "# a\n# b\n"
-        @comment5 = "# a\n# b\n# c\n# d\n"
-      end
-
-      it "should correctly extract multi-line comments" do
-        method(:comment_test1).comment.should == @comment1
-      end
-
-      it "should correctly strip leading whitespace before comments" do
-        method(:comment_test2).comment.should == @comment2
-      end
+    it "should correctly extract multi-line comments" do
+      method(:comment_test1).comment.should == @comment1
+    end
 
-      it "should keep empty comment lines" do
-        method(:comment_test3).comment.should == @comment3
-      end
-      
-      it "should ignore blank lines between comments" do
-        method(:comment_test4).comment.should == @comment4
-      end
+    it "should correctly strip leading whitespace before comments" do
+      method(:comment_test2).comment.should == @comment2
+    end
 
-      it "should align all comments to same indent level" do
-        method(:comment_test5).comment.should == @comment5
-      end      
+    it "should keep empty comment lines" do
+      method(:comment_test3).comment.should == @comment3
     end
+    
+    it "should ignore blank lines between comments" do
+      method(:comment_test4).comment.should == @comment4
+    end
+
+    it "should align all comments to same indent level" do
+      method(:comment_test5).comment.should == @comment5
+    end      
   end
 end
diff --git a/test/test_helper.rb b/test/test_helper.rb
index 78ef513..bb28e29 100644
--- a/test/test_helper.rb
+++ b/test/test_helper.rb
@@ -1,4 +1,10 @@
-  # A comment for hello
+class String
+  def clear
+    replace("")
+  end
+end
+
+# A comment for hello
   
   # It spans two lines and is indented by 2 spaces
 def hello; :hello; end