Add Foo.any_instance.stub!

Closes LH[#28] (patch from Scott Taylor)

lib/spec/mocks.rb

@@ -2,13 +2,15 @@
 require 'spec/mocks/argument_constraint_matchers'
 require 'spec/mocks/spec_methods'
 require 'spec/mocks/proxy'
+require 'spec/mocks/any_instance'
 require 'spec/mocks/mock'
 require 'spec/mocks/argument_expectation'
 require 'spec/mocks/message_expectation'
 require 'spec/mocks/order_group'
 require 'spec/mocks/errors'
 require 'spec/mocks/error_generator'
 require 'spec/mocks/extensions/object'
+require 'spec/mocks/extensions/class'
 require 'spec/mocks/space'
 
 

lib/spec/mocks/any_instance.rb

@@ -0,0 +1,27 @@
+require File.dirname(__FILE__) + "/any_instance/method_stubber"
+require File.dirname(__FILE__) + "/any_instance/any_instance_proxy"
+require File.dirname(__FILE__) + "/any_instance/methods"
+
+module Spec
+  module Mocks
+    # An addition to rspec's mock/stub library which
+    # will allow stubs to be included to all instances of a class. 
+    #
+    # MyClass.any_instance.stub!(:foo).and_return :my_value
+    #
+    # MyClass.new.foo #=> :my_value
+    # MyClass.new.foo #=> :my_value
+    #
+    # 
+    # Regular instance level stubs will still work as usual,
+    # overriding the behavior of stubbing all instances of a class:
+    #
+    # MyClass.any_instance.stub!(:my_method).and_return :foo
+    # instance = MyClass.new
+    # instance.stub!(:my_method).and_return :bar
+    # instance.my_method  #=> :bar
+    #
+    module AnyInstance
+    end
+  end
+end

lib/spec/mocks/any_instance/any_instance_proxy.rb

@@ -0,0 +1,31 @@
+module Spec
+  module Mocks
+    module AnyInstance
+      class AnyInstanceProxy
+
+        def initialize(target)
+          @target = target
+          @stubbed_methods = []
+        end
+
+        def stub!(message)
+          stubber = MethodStubber.new @target, message
+          stubber.add_stub
+          register_stub stubber
+          stubber
+        end
+
+        def reset
+          @stubbed_methods.each { |object| object.reset! }
+        end
+
+        private
+
+        def register_stub(stubber)
+          $rspec_mocks.add stubber
+          @stubbed_methods << stubber
+        end
+      end
+    end
+  end
+end

lib/spec/mocks/any_instance/method_stubber.rb

@@ -0,0 +1,67 @@
+module Spec
+  module Mocks
+    module AnyInstance
+      class MethodStubber
+
+        def initialize(target, message)
+          @target = target
+          @message = message
+          @munged_sym = "__rspec_proxy_any_instance_#{message}".to_sym
+        end
+
+        def add_stub
+          add_stub_with_value nil
+        end
+
+        def and_return(value)
+          add_stub_with_value value
+        end
+
+        def and_raise(*raise_params)
+          add_stub_with_error *raise_params
+        end
+
+        def reset!
+          swap_methods @munged_sym, @message
+          @target.send(:remove_method, @munged_sym) if @target.method_defined?(@munged_sym)
+        end
+        alias_method :rspec_reset, :reset!
+
+        def verified?
+          @verified
+        end
+
+        def rspec_verify
+          @verified = true
+        end
+
+        private
+        def define_stub(&impl)
+          store_current_instance_method do |message|
+            @target.send(:define_method, message, &impl)
+          end
+        end
+
+        def add_stub_with_value(value)
+          define_stub { value }
+        end
+
+        def add_stub_with_error(*raise_params)
+          define_stub { raise *raise_params }
+        end
+
+        def store_current_instance_method(&block)
+          swap_methods @message, @munged_sym, &block
+        end
+
+        def swap_methods(first, second)
+          @target.class_eval do
+            alias_method second, first if method_defined?(first)
+          end
+          yield first if block_given?
+        end
+
+      end
+    end
+  end
+end

lib/spec/mocks/any_instance/methods.rb

@@ -0,0 +1,22 @@
+module Spec
+  module Mocks
+    module AnyInstance
+      module Methods
+        # See the documentation under Spec::Mocks::AnyInstance
+        def any_instance
+          yield __any_instance_proxy__ if block_given?
+          __any_instance_proxy__
+        end
+
+        def __rspec_clear_instances__
+          __any_instance_proxy__.reset
+        end
+
+        private
+        def __any_instance_proxy__
+          @__any_instance_proxy__ ||= AnyInstanceProxy.new(self)
+        end
+      end
+    end
+  end
+end

lib/spec/mocks/extensions/class.rb

@@ -0,0 +1,3 @@
+class Class
+  include Spec::Mocks::AnyInstance::Methods
+end