Allow users to specify return values by passing a block to #at_least,…

… #at_most and #exactly.

- @mock.should_receive(:to_s).at_least(:once) { "return val" }
- @mock.should_receive(:to_s).at_most(:once) { "return val" }
- @mock.should_receive(:to_s).exactly(:once) { "return val" }

Each of the above now work but previously returned nothing since the block was discarded.

Closes #40.

lib/rspec/mocks/message_expectation.rb

@@ -254,17 +254,20 @@ def with(*args, &block)
         self
       end
 
-      def exactly(n)
+      def exactly(n, &block)
+        @method_block = block if block
         set_expected_received_count :exactly, n
         self
       end
 
-      def at_least(n)
+      def at_least(n, &block)
+        @method_block = block if block
         set_expected_received_count :at_least, n
         self
       end
 
-      def at_most(n)
+      def at_most(n, &block)
+        @method_block = block if block
         set_expected_received_count :at_most, n
         self
       end

spec/rspec/mocks/at_least_spec.rb

@@ -92,6 +92,12 @@ module Mocks
         @mock.random_call
         @mock.rspec_verify
       end
+
+      it "returns the value given by a block when the at least once method is called" do
+        @mock.should_receive(:to_s).at_least(:once) { "testing" }
+        @mock.to_s.should == "testing"
+        @mock.rspec_verify
+      end
     end
   end
 end

spec/rspec/mocks/at_most_spec.rb

@@ -88,6 +88,12 @@ module Mocks
         @mock.should_receive(:random_call).at_most(:twice)
         @mock.rspec_verify
       end
+
+      it "returns the value given by a block when the at most once method is called" do
+        @mock.should_receive(:to_s).at_most(:once) { "testing" }
+        @mock.to_s.should == "testing"
+        @mock.rspec_verify
+      end
     end
   end
 end

spec/rspec/mocks/precise_counts_spec.rb

@@ -31,6 +31,12 @@ module Mocks
         @mock.rspec_verify
       end
 
+      it "returns the value given by a block when the exactly once method is called" do
+        @mock.should_receive(:to_s).exactly(:once) { "testing" }
+        @mock.to_s.should == "testing"
+        @mock.rspec_verify
+      end
+
       it "passes multiple calls with different args and counts" do
         @mock.should_receive(:random_call).twice.with(1)
         @mock.should_receive(:random_call).once.with(2)