Generalize should == into should.predicate for any predicate

Author: eregon

lib/mspec/expectations/expectations.rb

@@ -18,4 +18,15 @@ def self.fail_with(expected, actual)
     end
     raise SpecExpectationNotMetError, message
   end
+
+  def self.fail_predicate(receiver, predicate, args, block, result, expectation)
+    receiver_to_s = MSpec.format(receiver)
+    before_method = predicate.to_s =~ /^[a-z]/ ? "." : " "
+    predicate_to_s = "#{before_method}#{predicate}"
+    predicate_to_s += " " unless args.empty?
+    args_to_s = args.map { |arg| MSpec.format(arg) }.join(', ')
+    args_to_s += " { ... }" if block
+    result_to_s = MSpec.format(result)
+    raise SpecExpectationNotMetError, "Expected #{receiver_to_s}#{predicate_to_s}#{args_to_s}\n#{expectation} but was #{result_to_s}"
+  end
 end

lib/mspec/matchers/base.rb

@@ -10,98 +10,52 @@ class Module
   include MSpecMatchers
 end
 
-class SpecPositiveOperatorMatcher
+class SpecPositiveOperatorMatcher < BasicObject
   def initialize(actual)
     @actual = actual
   end
 
   def ==(expected)
-    unless @actual == expected
-      SpecExpectation.fail_with("Expected #{MSpec.format(@actual)}",
-                            "to equal #{MSpec.format(expected)}")
-    end
+    method_missing(:==, expected)
   end
 
-  def <(expected)
-    unless @actual < expected
-      SpecExpectation.fail_with("Expected #{MSpec.format(@actual)}",
-                            "to be less than #{MSpec.format(expected)}")
-    end
-  end
-
-  def <=(expected)
-    unless @actual <= expected
-      SpecExpectation.fail_with("Expected #{MSpec.format(@actual)}",
-                            "to be less than or equal to #{MSpec.format(expected)}")
-    end
+  def !=(expected)
+    method_missing(:!=, expected)
   end
 
-  def >(expected)
-    unless @actual > expected
-      SpecExpectation.fail_with("Expected #{MSpec.format(@actual)}",
-                            "to be greater than #{MSpec.format(expected)}")
-    end
-  end
-
-  def >=(expected)
-    unless @actual >= expected
-      SpecExpectation.fail_with("Expected #{MSpec.format(@actual)}",
-                            "to be greater than or equal to #{MSpec.format(expected)}")
-    end
+  def equal?(expected)
+    method_missing(:equal?, expected)
   end
 
-  def =~(expected)
-    unless @actual =~ expected
-      SpecExpectation.fail_with("Expected #{MSpec.format(@actual)}",
-                            "to match #{MSpec.format(expected)}")
+  def method_missing(name, *args, &block)
+    result = @actual.__send__(name, *args, &block)
+    unless result
+      ::SpecExpectation.fail_predicate(@actual, name, args, block, result, "to be truthy")
     end
   end
 end
 
-class SpecNegativeOperatorMatcher
+class SpecNegativeOperatorMatcher < BasicObject
   def initialize(actual)
     @actual = actual
   end
 
   def ==(expected)
-    if @actual == expected
-      SpecExpectation.fail_with("Expected #{MSpec.format(@actual)}",
-                            "not to equal #{MSpec.format(expected)}")
-    end
+    method_missing(:==, expected)
   end
 
-  def <(expected)
-    if @actual < expected
-      SpecExpectation.fail_with("Expected #{MSpec.format(@actual)}",
-                            "not to be less than #{MSpec.format(expected)}")
-    end
-  end
-
-  def <=(expected)
-    if @actual <= expected
-      SpecExpectation.fail_with("Expected #{MSpec.format(@actual)}",
-                            "not to be less than or equal to #{MSpec.format(expected)}")
-    end
+  def !=(expected)
+    method_missing(:!=, expected)
   end
 
-  def >(expected)
-    if @actual > expected
-      SpecExpectation.fail_with("Expected #{MSpec.format(@actual)}",
-                            "not to be greater than #{MSpec.format(expected)}")
-    end
-  end
-
-  def >=(expected)
-    if @actual >= expected
-      SpecExpectation.fail_with("Expected #{MSpec.format(@actual)}",
-                            "not to be greater than or equal to #{MSpec.format(expected)}")
-    end
+  def equal?(expected)
+    method_missing(:equal?, expected)
   end
 
-  def =~(expected)
-    if @actual =~ expected
-      SpecExpectation.fail_with("Expected #{MSpec.format(@actual)}",
-                            "not to match #{MSpec.format(expected)}")
+  def method_missing(name, *args, &block)
+    result = @actual.__send__(name, *args, &block)
+    if result
+      ::SpecExpectation.fail_predicate(@actual, name, args, block, result, "to be falsy")
     end
   end
 end

spec/expectations/should_spec.rb

@@ -14,7 +14,8 @@
       @out.should include <<-EOS
 1)
 MSpec expectation method #should causes a failue to be recorded FAILED
-Expected 1 to equal 2
+Expected 1 == 2
+to be truthy but was false
 EOS
     end
 
@@ -32,7 +33,8 @@
       @out.should include <<-EOS
 3)
 MSpec expectation method #should_not causes a failure to be recorded FAILED
-Expected 1 not to equal 1
+Expected 1 == 1
+to be falsy but was true
 EOS
     end
 

spec/integration/run_spec.rb

@@ -5,7 +5,8 @@
 
 1)
 Foo#bar errors FAILED
-Expected 1 to equal 2
+Expected 1 == 2
+to be truthy but was false
 CWD/spec/fixtures/a_spec.rb:8:in `block (2 levels) in <top (required)>'
 CWD/spec/fixtures/a_spec.rb:2:in `<top (required)>'
 CWD/bin/mspec-run:7:in `<main>'

spec/integration/tag_spec.rb

@@ -24,14 +24,16 @@
 
 1)
 Tag#me errors FAILED
-Expected 1 to equal 2
+Expected 1 == 2
+to be truthy but was false
 CWD/spec/fixtures/tagging_spec.rb:9:in `block (2 levels) in <top (required)>'
 CWD/spec/fixtures/tagging_spec.rb:3:in `<top (required)>'
 CWD/bin/mspec-tag:7:in `<main>'
 
 2)
 Tag#me érròrs in unicode FAILED
-Expected 1 to equal 2
+Expected 1 == 2
+to be truthy but was false
 CWD/spec/fixtures/tagging_spec.rb:13:in `block (2 levels) in <top (required)>'
 CWD/spec/fixtures/tagging_spec.rb:3:in `<top (required)>'
 CWD/bin/mspec-tag:7:in `<main>'