Swap comparison of result object with the IGNORE_RESULT symbol. [Clos…

…es #1046]

lib/irb/context.rb

@@ -38,7 +38,7 @@ def to_s
 
     def evaluate(source)
       result = __evaluate__(source.to_s, '(irb)', @line - @source.buffer.size + 1)
-      unless result == IGNORE_RESULT
+      unless IGNORE_RESULT == result
         store_result(result)
         output(formatter.result(result))
         result

spec/context_spec.rb

@@ -110,6 +110,15 @@ def o.to_s; "self"; end
     @output.printed.should == "=> :bananas\n"
     @context.evaluate("_").should == :bananas
   end
+
+  describe "regression specs" do
+    it "does not try to convert an object to a string when checking if the evaluate result should be ignored" do
+      o = @context.__evaluate__("o = Object.new")
+      def o.==(other); raise "Ohnoes!"; end
+      lambda { @context.evaluate("o") }.should_not raise_error
+      @context.__evaluate__("exception").should == nil
+    end
+  end
 end
 
 describe "IRB::Context, when receiving input" do