Merge pull request #368 from rspec/simpler-failure-equal-singletons

Use a simpler message for equal on true false and nil

Changelog.md

@@ -1,6 +1,11 @@
 ### 3.0.0.beta2 Development
 [full changelog](http://github.com/rspec/rspec-expectations/compare/v3.0.0.beta1...v3.0.0.beta2)
 
+Ehancements:
+
+* Simplify the failure message of the `be` matcher when matching against:
+  `true`, `false` and `nil`. (Sam Phippen)
+
 Breaking Changes for 3.0.0:
 
 * Remove deprecated support for accessing the `RSpec` constant using

lib/rspec/matchers/built_in/equal.rb

@@ -7,17 +7,11 @@ def match(expected, actual)
         end
 
         def failure_message_for_should
-          return <<-MESSAGE
-
-expected #{inspect_object(expected)}
-     got #{inspect_object(actual)}
-
-Compared using equal?, which compares object identity,
-but expected and actual are not the same object. Use
-`#{eq_expression}` if you don't care about
-object identity in this example.
-
-MESSAGE
+          if expected_is_a_literal_singleton?
+            simple_failure_message
+          else
+            detailed_failure_message
+          end
         end
 
         def failure_message_for_should_not
@@ -31,10 +25,37 @@ def failure_message_for_should_not
 MESSAGE
         end
 
-        def diffable?; true; end
+        def diffable?
+          !expected_is_a_literal_singleton?
+        end
 
         private
 
+        LITERAL_SINGLETONS = [true, false, nil]
+
+        def expected_is_a_literal_singleton?
+          LITERAL_SINGLETONS.include?(expected)
+        end
+
+        def simple_failure_message
+          "\nexpected #{expected.inspect}\n     got #{inspect_object(actual)}\n"
+        end
+
+        def detailed_failure_message
+          return <<-MESSAGE
+
+expected #{inspect_object(expected)}
+     got #{inspect_object(actual)}
+
+Compared using equal?, which compares object identity,
+but expected and actual are not the same object. Use
+`#{eq_expression}` if you don't care about
+object identity in this example.
+
+MESSAGE
+        end
+
+
         def inspect_object(o)
           "#<#{o.class}:#{o.object_id}> => #{o.inspect}"
         end

spec/rspec/matchers/equal_spec.rb

@@ -50,6 +50,27 @@ def string.equal?(other)
         end
       end
 
+      it "prints a special message for `false`" do
+        expected, actual = false, "1"
+        expect {
+          expect(actual).to equal(expected)
+        }.to fail_with "\nexpected false\n     got #{inspect_object(actual)}\n"
+      end
+
+      it "prints a special message for `true`" do
+        expected, actual = true, "1"
+        expect {
+          expect(actual).to equal(expected)
+        }.to fail_with "\nexpected true\n     got #{inspect_object(actual)}\n"
+      end
+
+      it "prints a special message for `nil`" do
+        expected, actual = nil, "1"
+        expect {
+          expect(actual).to equal(expected)
+        }.to fail_with "\nexpected nil\n     got #{inspect_object(actual)}\n"
+      end
+
       it "suggests the `eq` matcher on failure" do
         expected, actual = "1", "1"
         expect {