method_double.rb in rspec-mocks-3.0.0.beta1

- old
+ new

@@ -1,33 +1,39 @@
 module RSpec
   module Mocks
     # @private
-    class MethodDouble < Hash
+    class MethodDouble
       # @private
-      attr_reader :method_name, :object
+      attr_reader :method_name, :object, :expectations, :stubs
 
       # @private
       def initialize(object, method_name, proxy)
         @method_name = method_name
         @object = object
         @proxy = proxy
 
-        @method_stasher = InstanceMethodStasher.new(object_singleton_class, @method_name)
+        @original_visibility = nil
+        @method_stasher = InstanceMethodStasher.new(object, method_name)
         @method_is_proxied = false
-        store(:expectations, [])
-        store(:stubs, [])
+        @expectations = []
+        @stubs = []
       end
 
-      # @private
-      def expectations
-        self[:expectations]
+      def original_method
+        # If original method is not present, uses the `method_missing`
+        # handler of the object. This accounts for cases where the user has not
+        # correctly defined `respond_to?`, and also 1.8 which does not provide
+        # method handles for missing methods even if `respond_to?` is correct.
+        @original_method ||=
+          @method_stasher.original_method ||
+          @proxy.method_handle_for(method_name) ||
+          Proc.new do |*args, &block|
+            @object.__send__(:method_missing, @method_name, *args, &block)
+          end
       end
 
-      # @private
-      def stubs
-        self[:stubs]
-      end
+      alias_method :save_original_method!, :original_method
 
       # @private
       def visibility
         if TestDouble === @object
           'public'
@@ -38,168 +44,66 @@
         else
           'public'
         end
       end
 
-      class ProcWithBlock < Struct.new(:object, :method_name)
-
-        def call(*args, &block)
-          self.object.__send__(:method_missing, self.method_name, *args, &block)
-        end
-
-      end
-
       # @private
-      def original_method
-        if @method_stasher.method_is_stashed?
-          # Example: a singleton method defined on @object
-          ::RSpec::Mocks.method_handle_for(@object, @method_stasher.stashed_method_name)
-        elsif meth = original_unrecorded_any_instance_method
-          # Example: a method that has been mocked through
-          #   klass.any_instance.should_receive(:msg).and_call_original
-          # any_instance.should_receive(:msg) causes the method to be
-          # replaced with a proxy method, and then `and_call_original`
-          # is recorded and played back on the object instance. We need
-          # special handling here to get a handle on the original method
-          # object rather than the proxy method.
-          meth
-        else
-          # Example: an instance method defined on one of @object's ancestors.
-          original_method_from_ancestry
-        end
-      rescue NameError
-        # We have no way of knowing if the object's method_missing
-        # will handle this message or not...but we can at least try.
-        # If it's not handled, a `NoMethodError` will be raised, just
-        # like normally.
-        ProcWithBlock.new(@object,@method_name)
-      end
-
-      def original_unrecorded_any_instance_method
-        return nil unless any_instance_class_recorder_observing_method?(@object.class)
-        alias_name = ::RSpec::Mocks.any_instance_recorder_for(@object.class).build_alias_method_name(@method_name)
-        @object.method(alias_name)
-      end
-
-      def any_instance_class_recorder_observing_method?(klass)
-        return true if ::RSpec::Mocks.any_instance_recorder_for(klass).already_observing?(@method_name)
-        superklass = klass.superclass
-        return false if superklass.nil?
-        any_instance_class_recorder_observing_method?(superklass)
-      end
-
-      our_singleton_class = class << self; self; end
-      if our_singleton_class.ancestors.include? our_singleton_class
-        # In Ruby 2.1, ancestors include the correct ancestors, including the singleton classes
-        def original_method_from_ancestry
-          # Lookup in the ancestry, skipping over the singleton class itself
-          original_method_from_ancestor(object_singleton_class.ancestors.drop(1))
-        end
-      else
-        # @private
-        def original_method_from_ancestry
-          original_method_from_ancestor(object_singleton_class.ancestors)
-        rescue NameError
-          raise unless @object.respond_to?(:superclass)
-
-          # Example: a singleton method defined on @object's superclass.
-          #
-          # Note: we have to give precedence to instance methods
-          # defined on @object's class, because in a case like:
-          #
-          # `klass.should_receive(:new).and_call_original`
-          #
-          # ...we want `Class#new` bound to `klass` (which will return
-          # an instance of `klass`), not `klass.superclass.new` (which
-          # would return an instance of `klass.superclass`).
-          original_method_from_superclass
-        end
-      end
-
-      def original_method_from_ancestor(ancestors)
-        klass, *rest = ancestors
-        klass.instance_method(@method_name).bind(@object)
-      rescue NameError
-        raise if rest.empty?
-        original_method_from_ancestor(rest)
-      end
-
-      if RUBY_VERSION.to_f > 1.8
-        # @private
-        def original_method_from_superclass
-          @object.superclass.
-                  singleton_class.
-                  instance_method(@method_name).
-                  bind(@object)
-        end
-      else
-        # Our implementation for 1.9 (above) causes an error on 1.8:
-        # TypeError: singleton method bound for a different object
-        #
-        # This doesn't work quite right in all circumstances but it's the
-        # best we can do.
-        # @private
-        def original_method_from_superclass
-          ::Kernel.warn <<-WARNING.gsub(/^ +\|/, '')
-            |
-            |WARNING: On ruby 1.8, rspec-mocks is unable to bind the original
-            |`#{@method_name}` method to your partial mock object (#{@object})
-            |for `and_call_original`. The superclass's `#{@method_name}` is being
-            |used instead; however, it may not work correctly when executed due
-            |to the fact that `self` will be #{@object.superclass}, not #{@object}.
-            |
-            |Called from: #{CallerFilter.first_non_rspec_line}
-          WARNING
-
-          @object.superclass.method(@method_name)
-        end
-      end
-      # @private
       def object_singleton_class
         class << @object; self; end
       end
 
       # @private
       def configure_method
-        @original_visibility = visibility_for_method
+        @original_visibility = [visibility, method_name]
         @method_stasher.stash unless @method_is_proxied
         define_proxy_method
       end
 
       # @private
       def define_proxy_method
         return if @method_is_proxied
 
-        object_singleton_class.class_eval <<-EOF, __FILE__, __LINE__ + 1
-          def #{@method_name}(*args, &block)
-            ::RSpec::Mocks.proxy_for(self).message_received :#{@method_name}, *args, &block
+        save_original_method!
+
+        object_singleton_class.class_exec(self, method_name, visibility) do |method_double, method_name, visibility|
+          define_method(method_name) do |*args, &block|
+            method_double.proxy_method_invoked(self, *args, &block)
           end
-          #{visibility_for_method}
-        EOF
+          self.__send__ visibility, method_name
+        end
+
         @method_is_proxied = true
       end
 
+      # The implementation of the proxied method. Subclasses may override this
+      # method to perform additional operations.
+      #
       # @private
-      def visibility_for_method
-        "#{visibility} :#{method_name}"
+      def proxy_method_invoked(obj, *args, &block)
+        @proxy.message_received method_name, *args, &block
       end
 
       # @private
       def restore_original_method
         return unless @method_is_proxied
 
         object_singleton_class.__send__(:remove_method, @method_name)
-        @method_stasher.restore
+        if @method_stasher.method_is_stashed?
+          @method_stasher.restore
+        end
         restore_original_visibility
 
         @method_is_proxied = false
       end
 
       # @private
       def restore_original_visibility
-        return unless object_singleton_class.method_defined?(@method_name) || object_singleton_class.private_method_defined?(@method_name)
-        object_singleton_class.class_eval(@original_visibility, __FILE__, __LINE__ + 1)
+        return unless @original_visibility &&
+          (object_singleton_class.method_defined?(@method_name) ||
+           object_singleton_class.private_method_defined?(@method_name))
+
+        object_singleton_class.__send__(*@original_visibility)
       end
 
       # @private
       def verify
         expectations.each {|e| e.verify_messages_received}
@@ -215,31 +119,65 @@
       def clear
         expectations.clear
         stubs.clear
       end
 
+      # The type of message expectation to create has been extracted to its own
+      # method so that subclasses can override it.
+      #
       # @private
+      def message_expectation_class
+        MessageExpectation
+      end
+
+      # @private
       def add_expectation(error_generator, expectation_ordering, expected_from, opts, &implementation)
         configure_method
-        expectation = MessageExpectation.new(error_generator, expectation_ordering,
+        expectation = message_expectation_class.new(error_generator, expectation_ordering,
                                              expected_from, self, 1, opts, &implementation)
         expectations << expectation
         expectation
       end
 
       # @private
       def build_expectation(error_generator, expectation_ordering)
         expected_from = IGNORED_BACKTRACE_LINE
-        MessageExpectation.new(error_generator, expectation_ordering, expected_from, self)
+        message_expectation_class.new(error_generator, expectation_ordering, expected_from, self)
       end
 
       # @private
       def add_stub(error_generator, expectation_ordering, expected_from, opts={}, &implementation)
         configure_method
-        stub = MessageExpectation.new(error_generator, expectation_ordering, expected_from,
+        stub = message_expectation_class.new(error_generator, expectation_ordering, expected_from,
                                       self, :any, opts, &implementation)
         stubs.unshift stub
         stub
+      end
+
+      # A simple stub can only return a concrete value for a message, and
+      # cannot match on arguments. It is used as an optimization over
+      # `add_stub` / `add_expectation` where it is known in advance that this
+      # is all that will be required of a stub, such as when passing attributes
+      # to the `double` example method. They do not stash or restore existing method
+      # definitions.
+      #
+      # @private
+      def add_simple_stub(method_name, response)
+        setup_simple_method_double method_name, response, stubs
+      end
+
+      # @private
+      def add_simple_expectation(method_name, response, error_generator, backtrace_line)
+        setup_simple_method_double method_name, response, expectations, error_generator, backtrace_line
+      end
+
+      # @private
+      def setup_simple_method_double(method_name, response, collection, error_generator = nil, backtrace_line = nil)
+        define_proxy_method
+
+        me = SimpleMessageExpectation.new(method_name, response, error_generator, backtrace_line)
+        collection.unshift me
+        me
       end
 
       # @private
       def add_default_stub(*args, &implementation)
         return if stubs.any?