class FlexMock::PartialMockProxy

######################################################################### PartialMockProxy is used to mate the mock framework to an existing object. The object is “enhanced” with a reference to a mock object (stored in @flexmock_proxy). When the should_receive method is sent to the proxy, it overrides the existing object's method by creating singleton method that forwards to the mock. When testing is complete, PartialMockProxy will erase the mocking infrastructure from the object being mocked (e.g. remove instance variables and mock singleton methods).

Constants

MOCK_METHODS

The following methods are added to partial mocks so that they can act like a mock.

Attributes

mock[R]

Public Class Methods

new(obj, mock, safe_mode) click to toggle source

Initialize a PartialMockProxy object.

# File lib/flexmock/partial_mock.rb, line 42
def initialize(obj, mock, safe_mode)
  @obj = obj
  @mock = mock
  @method_definitions = {}
  @methods_proxied = []
  unless safe_mode
    add_mock_method(:should_receive)
    MOCK_METHODS.each do |sym|
      unless @obj.respond_to?(sym)
        add_mock_method(sym)
      end
    end
  end
end

Public Instance Methods

add_mock_method(method_name) click to toggle source
# File lib/flexmock/partial_mock.rb, line 98
def add_mock_method(method_name)
  stow_existing_definition(method_name)
  sclass.module_eval do
    define_method(method_name) { |*args, &block|
      proxy = instance_variable_get("@flexmock_proxy")
      if proxy.nil?
        fail "Missing FlexMock proxy " +
          "(for method_name=#{method_name.inspect}, self=\#{self})"
      end
      proxy.send(method_name, *args, &block)
    }
  end
end
any_instance(&block) click to toggle source

#any_instance is present for backwards compatibility with version 0.5.0. @deprecated

# File lib/flexmock/deprecated_methods.rb, line 53
def any_instance(&block)
  $stderr.puts "any_instance is deprecated, use new_instances instead."
  new_instances(&block)
end
flexmock_based_on(*args) click to toggle source

Forward the based on request.

# File lib/flexmock/partial_mock.rb, line 209
def flexmock_based_on(*args)
  @mock.flexmock_based_on(*args)
end
flexmock_calls() click to toggle source

Forward to the mock

# File lib/flexmock/partial_mock.rb, line 194
def flexmock_calls
  @mock.flexmock_calls
end
flexmock_container() click to toggle source

Forward to the mock's container.

# File lib/flexmock/partial_mock.rb, line 184
def flexmock_container
  @mock.flexmock_container
end
flexmock_container=(container) click to toggle source

Set the proxy's mock container. This set value is ignored because the proxy always uses the container of its mock.

# File lib/flexmock/partial_mock.rb, line 200
def flexmock_container=(container)
end
flexmock_define_expectation(location, *args) click to toggle source
# File lib/flexmock/partial_mock.rb, line 87
def flexmock_define_expectation(location, *args)
  ContainerHelper.parse_should_args(@mock, args) do |sym|
    unless @methods_proxied.include?(sym)
      hide_existing_method(sym)
    end
    ex = @mock.flexmock_define_expectation(location, sym)
    ex.mock = self
    ex
  end
end
flexmock_expectations_for(method_name) click to toggle source

Forward the request for the expectation director to the mock.

# File lib/flexmock/partial_mock.rb, line 204
def flexmock_expectations_for(method_name)
  @mock.flexmock_expectations_for(method_name)
end
flexmock_get() click to toggle source

Get the mock object for the partial mock.

# File lib/flexmock/partial_mock.rb, line 58
def flexmock_get
  @mock
end
flexmock_invoke_original(method, args) click to toggle source
# File lib/flexmock/partial_mock.rb, line 161
def flexmock_invoke_original(method, args)
  invoke_original(method, args)
end
flexmock_received?(*args) click to toggle source

Forward to the mock

# File lib/flexmock/partial_mock.rb, line 189
def flexmock_received?(*args)
  @mock.flexmock_received?(*args)
end
flexmock_teardown() click to toggle source

Remove all traces of the mocking framework from the existing object.

# File lib/flexmock/partial_mock.rb, line 172
def flexmock_teardown
  if ! detached?
    @methods_proxied.each do |method_name|
      remove_current_method(method_name)
      restore_original_definition(method_name)
    end
    @obj.instance_variable_set("@flexmock_proxy", nil)
    @obj = nil
  end
end
flexmock_verify() click to toggle source

Verify that the mock has been properly called. After verification, detach the mocking infrastructure from the existing object.

# File lib/flexmock/partial_mock.rb, line 167
def flexmock_verify
  @mock.flexmock_verify
end
should_receive(...) click to toggle source
new_instances { |instance| instance.should_receive(...) }

#new_instances is a short cut method for overriding the behavior of any new instances created via a mocked class object.

By default, #new_instances will mock the behaviour of the :new method. If you wish to mock a different set of class methods, just pass a list of symbols to as arguments. (previous versions also mocked :allocate by default. If you need :allocate to be mocked, just request it explicitly).

For example, to stub only objects created by :make (and not :new), use:

flexmock(ClassName).new_instances(:make).should_receive(...)
# File lib/flexmock/partial_mock.rb, line 130
def new_instances(*allocators, &block)
  fail ArgumentError, "new_instances requires a Class to stub" unless Class === @obj
  location = caller.first
  allocators = [:new] if allocators.empty?
  result = ExpectationRecorder.new
  allocators.each do |allocate_method|
    check_allocate_method(allocate_method)
    # HACK: Without the following lambda, Some versions of Ruby 1.9
    #       would not bind the allocate_method parameter
    #       correctly. I don't think it is necessary for recent
    #       versions.
    lambda { }
    self.flexmock_define_expectation(location, allocate_method).and_return { |*args|
      new_obj = invoke_original(allocate_method, args)
      mock = flexmock_container.flexmock(new_obj)
      block.call(mock) if block_given?
      result.apply(mock)
      new_obj
    }
  end
  result
end
should_receive(:method_name) click to toggle source
should_receive(:method1, method2, ...)
should_receive(:meth1 => result1, :meth2 → result2, ...)

Declare that the partial mock should receive a message with the given name.

If more than one method name is given, then the mock object should expect to receive all the listed melthods. If a hash of method name/value pairs is given, then the each method will return the associated result. Any expectations applied to the result of should_receive will be applied to all the methods defined in the argument list.

An expectation object for the method name is returned as the result of this method. Further expectation constraints can be added by chaining to the result.

See Expectation for a list of declarators that can be used.

# File lib/flexmock/partial_mock.rb, line 82
def should_receive(*args)
  location = caller.first
  flexmock_define_expectation(location, *args)
end

Private Instance Methods

check_allocate_method(allocate_method) click to toggle source
# File lib/flexmock/partial_mock.rb, line 215
def check_allocate_method(allocate_method)
  if allocate_method == :allocate && RUBY_VERSION >= "1.9"
    fail UsageError, "Cannot mock the allocation method using new_instances in Ruby 1.9"
  end
end
create_alias_for_existing_method(method_name) click to toggle source

Create an alias for the existing method_name. Returns the new alias name. If the aliasing process fails (because the method doesn't really exist, then return nil.

# File lib/flexmock/partial_mock.rb, line 263
def create_alias_for_existing_method(method_name)
  new_alias = new_name(method_name)
  unless @obj.respond_to?(new_alias)
    safe_alias_method(new_alias, method_name)
  end
  new_alias
end
define_proxy_method(method_name) click to toggle source

Define a proxy method that forwards to our mock object. The proxy method is defined as a singleton method on the object being mocked.

# File lib/flexmock/partial_mock.rb, line 288
def define_proxy_method(method_name)
  if method_name.to_s =~ /=$/
    eval_line = __LINE__ + 1
    sclass.class_eval %Q{
      def #{method_name}(*args, &block)
        instance_variable_get('@flexmock_proxy').mock.__send__(:#{method_name}, *args, &block)
      end
    }, __FILE__, eval_line
  else
    eval_line = __LINE__ + 1
    sclass.class_eval %Q{
      def #{method_name}(*args, &block)
        instance_variable_get('@flexmock_proxy').mock.#{method_name}(*args, &block)
      end
    }, __FILE__, eval_line
    _ = true       # make rcov recognize the above eval is covered
  end
end
detached?() click to toggle source

Have we been detached from the existing object?

# File lib/flexmock/partial_mock.rb, line 331
def detached?
  @obj.nil?
end
hide_existing_method(method_name) click to toggle source

Hide the existing method definition with a singleton defintion that proxies to our mock object. If the current definition is a singleton, we need to record the definition and remove it before creating our own singleton method. If the current definition is not a singleton, all we need to do is override it with our own singleton.

# File lib/flexmock/partial_mock.rb, line 236
def hide_existing_method(method_name)
  stow_existing_definition(method_name)
  define_proxy_method(method_name)
end
invoke_original(method, args) click to toggle source

Invoke the original definition of method on the object supported by the stub.

# File lib/flexmock/partial_mock.rb, line 155
def invoke_original(method, args)
  method_proc = @method_definitions[method]
  method_proc.call(*args)
end
new_name(old_name) click to toggle source

Generate a name to be used to alias the original behavior.

# File lib/flexmock/partial_mock.rb, line 336
def new_name(old_name)
  "flexmock_original_behavior_for_#{old_name}"
end
remove_current_method(method_name) click to toggle source

Remove the current method if it is a singleton method of the object being mocked.

# File lib/flexmock/partial_mock.rb, line 326
def remove_current_method(method_name)
  sclass.class_eval { remove_method(method_name) }
end
restore_original_definition(method_name) click to toggle source

Restore the original singleton defintion for method_name that was saved earlier.

# File lib/flexmock/partial_mock.rb, line 309
def restore_original_definition(method_name)
  begin
    method_def = @method_definitions[method_name]
    if method_def
      the_alias = new_name(method_name)
      sclass.class_eval do
        alias_method(method_name, the_alias)
      end
    end
  rescue NameError => _
    # Alias attempt failed
    nil
  end
end
safe_alias_method(new_alias, method_name) click to toggle source

Create an alias for the existing method named method_name. It is possible that method_name is implemented via a meta-programming, so we provide for the case that the method_name does not exist.

# File lib/flexmock/partial_mock.rb, line 275
def safe_alias_method(new_alias, method_name)
  sclass.class_eval do
    begin
      alias_method(new_alias, method_name)
    rescue NameError
      nil
    end
  end
end
sclass() click to toggle source

The singleton class of the object.

# File lib/flexmock/partial_mock.rb, line 222
def sclass
  class << @obj; self; end
end
singleton?(method_name) click to toggle source
# File lib/flexmock/partial_mock.rb, line 226
def singleton?(method_name)
  @obj.flexmock_singleton_defined?(method_name)
end
stow_existing_definition(method_name) click to toggle source

Stow the existing method definition so that it can be recovered later.

# File lib/flexmock/partial_mock.rb, line 243
def stow_existing_definition(method_name)
  @methods_proxied << method_name
  new_alias = create_alias_for_existing_method(method_name)
  if new_alias
    my_object = @obj
    @method_definitions[method_name] = Proc.new { |*args|
      block = nil
      if Proc === args.last
        block = args.last
        args = args[0...-1]
      end
      my_object.send(new_alias, *args, &block)
    }
  end
  remove_current_method(method_name) if singleton?(method_name)
end