Revert "Make debugger statements _just work_"

- restore the --debugger/-d option
- this created a situation in which debugger did not work at all with
  rails, so need to figure out a different solution

This reverts commit 2466831.

Upgrade.markdown

@@ -94,7 +94,7 @@ JRuby installation to a newer release that allows the example to pass, RSpec
 will report it as a failure (`Expected pending '...' to fail.  No Error was raised.`),
 so that know that you can remove the call to `pending`.
 
-# rspec-core-2.0
+# New features in rspec-core-2.0
 
 ### Runner
 

lib/rspec/core/configuration.rb

@@ -176,11 +176,21 @@ def requires=(paths)
       end
 
       def debug=(bool)
-        RSpec.warn_deprecation <<-WARNING
-The debug option (config.debug = true or --debug/-d on the command line)
-is deprecated and no longer has any effect. This message will be removed
-from future versions of RSpec.
-WARNING
+        return unless bool
+        begin
+          require 'ruby-debug'
+        rescue LoadError
+          raise <<-EOM
+
+#{'*'*50}
+You must install ruby-debug to run rspec with the --debug option.
+
+If you have ruby-debug installed as a ruby gem, then you need to either
+require 'rubygems' or configure the RUBYOPT environment variable with
+the value 'rubygems'.
+#{'*'*50}
+EOM
+        end
       end
 
       def line_number=(line_number)

lib/rspec/core/extensions/kernel.rb

@@ -1,27 +1,5 @@
 module Kernel
-
-  private
-
-  alias_method :method_missing_without_debugger, :method_missing
-
-  def method_missing(m, *a)
-    if m.to_s == 'debugger'
-      begin
-        require 'ruby-debug'
-        debugger
-      rescue LoadError => e
-        warn <<-EOM
-#{'*'*50}
-The debugger statement on the following line was ignored:
-
-  #{caller(0).detect {|l| l !~ /method_missing/}}
- 
-To use the debugger statement, you must install ruby-debug.
-#{'*'*50}
-EOM
-      end
-    else
-      method_missing_without_debugger(m, *a)
-    end
-  end
+  def debugger(*args)
+    RSpec.configuration.error_stream.puts "debugger statement ignored, use -d or --debug option to enable debugging\n#{caller(0)[1]}"
+  end unless respond_to?(:debugger)
 end

spec/rspec/core/configuration_spec.rb

@@ -503,13 +503,20 @@ def that_thing
       end
     end
 
-    describe "#debug=" do
-      it "is deprecated" do
-        RSpec.should_receive(:warn_deprecation)
+    describe "#debug=true" do
+      it "requires 'ruby-debug'" do
+        config.should_receive(:require).with('ruby-debug')
         config.debug = true
       end
     end
 
+    describe "#debug=false" do
+      it "does not require 'ruby-debug'" do
+        config.should_not_receive(:require).with('ruby-debug')
+        config.debug = false
+      end
+    end
+
     describe "#output=" do
       it "sets the output" do
         output = mock("output")

spec/rspec/core/kernel_extensions_spec.rb

@@ -1,12 +1,9 @@
 require 'spec_helper'
 
 describe "extensions" do
-  describe "#debugger" do
-    it "warns if ruby-debug is not installed" do
-      object = Object.new
-      object.should_receive(:warn).with(/debugger .* ignored:\n.* ruby-debug/m)
-      object.stub(:require) { raise LoadError }
-      object.__send__ :method_missing, :debugger
+  describe "debugger" do
+    it "is defined on Kernel" do
+      Kernel.should respond_to(:debugger)
     end
   end
 end