module RSpec
module Mocks
class MessageExpectation
# @private
attr_accessor :error_generator, :implementation
attr_reader :message
attr_writer :expected_received_count, :expected_from, :argument_list_matcher
protected :expected_received_count=, :expected_from=, :error_generator, :error_generator=, :implementation=
# @private
def initialize(error_generator, expectation_ordering, expected_from, method_double,
expected_received_count=1, opts={}, &implementation_block)
@error_generator = error_generator
@error_generator.opts = opts
@expected_from = expected_from
@method_double = method_double
@message = @method_double.method_name
@actual_received_count = 0
@expected_received_count = expected_received_count
@argument_list_matcher = ArgumentListMatcher.new(ArgumentMatchers::AnyArgsMatcher.new)
@order_group = expectation_ordering
@at_least = @at_most = @exactly = nil
@args_to_yield = []
@failed_fast = nil
@eval_context = nil
@implementation = Implementation.new
self.inner_implementation_action = implementation_block
end
# @private
# @private
def expected_args
@argument_list_matcher.expected_args
end
# @overload and_return(value)
# @overload and_return(first_value, second_value)
# @overload and_return(&block)
#
# Tells the object to return a value when it receives the message. Given
# more than one value, the first value is returned the first time the
# message is received, the second value is returned the next time, etc,
# etc.
#
# If the message is received more times than there are values, the last
# value is received for every subsequent call.
#
# The block format is still supported, but is unofficially deprecated in
# favor of just passing a block to the stub method.
#
# @example
#
# counter.stub(:count).and_return(1)
# counter.count # => 1
# counter.count # => 1
#
# counter.stub(:count).and_return(1,2,3)
# counter.count # => 1
# counter.count # => 2
# counter.count # => 3
# counter.count # => 3
# counter.count # => 3
# # etc
#
# # Supported, but ...
# counter.stub(:count).and_return { 1 }
# counter.count # => 1
#
# # ... this is prefered
# counter.stub(:count) { 1 }
# counter.count # => 1
def and_return(*values, &implementation)
@expected_received_count = [@expected_received_count, values.size].max unless ignoring_args? || (@expected_received_count == 0 and @at_least)
if implementation
# TODO: deprecate `and_return { value }`
self.inner_implementation_action = implementation
else
self.terminal_implementation_action = AndReturnImplementation.new(values)
end
nil
end
# Tells the object to delegate to the original unmodified method
# when it receives the message.
#
# @note This is only available on partial mock objects.
#
# @example
#
# counter.should_receive(:increment).and_call_original
# original_count = counter.count
# counter.increment
# expect(counter.count).to eq(original_count + 1)
def and_call_original
if @method_double.object.is_a?(RSpec::Mocks::TestDouble)
@error_generator.raise_only_valid_on_a_partial_mock(:and_call_original)
else
@implementation = AndCallOriginalImplementation.new(@method_double.original_method)
end
end
# @overload and_raise
# @overload and_raise(ExceptionClass)
# @overload and_raise(ExceptionClass, message)
# @overload and_raise(exception_instance)
#
# Tells the object to raise an exception when the message is received.
#
# @note
#
# When you pass an exception class, the MessageExpectation will raise
# an instance of it, creating it with `exception` and passing `message`
# if specified. If the exception class initializer requires more than
# one parameters, you must pass in an instance and not the class,
# otherwise this method will raise an ArgumentError exception.
#
# @example
#
# car.stub(:go).and_raise
# car.stub(:go).and_raise(OutOfGas)
# car.stub(:go).and_raise(OutOfGas, "At least 2 oz of gas needed to drive")
# car.stub(:go).and_raise(OutOfGas.new(2, :oz))
def and_raise(exception = RuntimeError, message = nil)
if exception.respond_to?(:exception)
exception = message ? exception.exception(message) : exception.exception
end
self.terminal_implementation_action = Proc.new { raise exception }
nil
end
# @overload and_throw(symbol)
# @overload and_throw(symbol, object)
#
# Tells the object to throw a symbol (with the object if that form is
# used) when the message is received.
#
# @example
#
# car.stub(:go).and_throw(:out_of_gas)
# car.stub(:go).and_throw(:out_of_gas, :level => 0.1)
def and_throw(*args)
self.terminal_implementation_action = Proc.new { throw *args }
nil
end
# Tells the object to yield one or more args to a block when the message
# is received.
#
# @example
#
# stream.stub(:open).and_yield(StringIO.new)
def and_yield(*args, &block)
yield @eval_context = Object.new.extend(RSpec::Mocks::InstanceExec) if block
@args_to_yield << args
self.initial_implementation_action = AndYieldImplementation.new(@args_to_yield, @eval_context, @error_generator)
self
end
# @private
def matches?(message, *args)
@message == message && @argument_list_matcher.args_match?(*args)
end
# @private
def invoke(parent_stub, *args, &block)
if (@expected_received_count == 0 && !@at_least) || ((@exactly || @at_most) && (@actual_received_count == @expected_received_count))
@actual_received_count += 1
@failed_fast = true
@error_generator.raise_expectation_error(@message, @expected_received_count, @actual_received_count, *args)
end
@order_group.handle_order_constraint self
begin
if implementation.present?
implementation.call(*args, &block)
elsif parent_stub
parent_stub.invoke(nil, *args, &block)
end
ensure
@actual_received_count += 1
end
end
# @private
def called_max_times?
@expected_received_count != :any &&
!@at_least &&
@expected_received_count > 0 &&
@actual_received_count >= @expected_received_count
end
# @private
def matches_name_but_not_args(message, *args)
@message == message and not @argument_list_matcher.args_match?(*args)
end
# @private
def verify_messages_received
generate_error unless expected_messages_received? || failed_fast?
rescue RSpec::Mocks::MockExpectationError => error
error.backtrace.insert(0, @expected_from)
Kernel::raise error
end
# @private
def expected_messages_received?
ignoring_args? || matches_exact_count? || matches_at_least_count? || matches_at_most_count?
end
# @private
def ignoring_args?
@expected_received_count == :any
end
# @private
def matches_at_least_count?
@at_least && @actual_received_count >= @expected_received_count
end
# @private
def matches_at_most_count?
@at_most && @actual_received_count <= @expected_received_count
end
# @private
def matches_exact_count?
@expected_received_count == @actual_received_count
end
# @private
def similar_messages
@similar_messages ||= []
end
# @private
def advise(*args)
similar_messages << args
end
# @private
def generate_error
if similar_messages.empty?
@error_generator.raise_expectation_error(@message, @expected_received_count, @actual_received_count, *expected_args)
else
@error_generator.raise_similar_message_args_error(self, *@similar_messages)
end
end
def raise_out_of_order_error
@error_generator.raise_out_of_order_error @message
end
# Constrains a stub or message expectation to invocations with specific
# arguments.
#
# With a stub, if the message might be received with other args as well,
# you should stub a default value first, and then stub or mock the same
# message using `with` to constrain to specific arguments.
#
# A message expectation will fail if the message is received with different
# arguments.
#
# @example
#
# cart.stub(:add) { :failure }
# cart.stub(:add).with(Book.new(:isbn => 1934356379)) { :success }
# cart.add(Book.new(:isbn => 1234567890))
# # => :failure
# cart.add(Book.new(:isbn => 1934356379))
# # => :success
#
# cart.should_receive(:add).with(Book.new(:isbn => 1934356379)) { :success }
# cart.add(Book.new(:isbn => 1234567890))
# # => failed expectation
# cart.add(Book.new(:isbn => 1934356379))
# # => passes
def with(*args, &block)
self.inner_implementation_action = block if block_given? unless args.empty?
@argument_list_matcher = ArgumentListMatcher.new(*args, &block)
self
end
# Constrain a message expectation to be received a specific number of
# times.
#
# @example
#
# dealer.should_receive(:deal_card).exactly(10).times
def exactly(n, &block)
self.inner_implementation_action = block
set_expected_received_count :exactly, n
self
end
# Constrain a message expectation to be received at least a specific
# number of times.
#
# @example
#
# dealer.should_receive(:deal_card).at_least(9).times
def at_least(n, &block)
self.inner_implementation_action = block
set_expected_received_count :at_least, n
self
end
# Constrain a message expectation to be received at most a specific
# number of times.
#
# @example
#
# dealer.should_receive(:deal_card).at_most(10).times
def at_most(n, &block)
self.inner_implementation_action = block
set_expected_received_count :at_most, n
self
end
# Syntactic sugar for `exactly`, `at_least` and `at_most`
#
# @example
#
# dealer.should_receive(:deal_card).exactly(10).times
# dealer.should_receive(:deal_card).at_least(10).times
# dealer.should_receive(:deal_card).at_most(10).times
def times(&block)
self.inner_implementation_action = block
self
end
# Allows an expected message to be received any number of times.
def any_number_of_times(&block)
self.inner_implementation_action = block
@expected_received_count = :any
self
end
# Expect a message not to be received at all.
#
# @example
#
# car.should_receive(:stop).never
def never
@expected_received_count = 0
self
end
# Expect a message to be received exactly one time.
#
# @example
#
# car.should_receive(:go).once
def once(&block)
self.inner_implementation_action = block
set_expected_received_count :exactly, 1
self
end
# Expect a message to be received exactly two times.
#
# @example
#
# car.should_receive(:go).twice
def twice(&block)
self.inner_implementation_action = block
set_expected_received_count :exactly, 2
self
end
# Expect messages to be received in a specific order.
#
# @example
#
# api.should_receive(:prepare).ordered
# api.should_receive(:run).ordered
# api.should_receive(:finish).ordered
def ordered(&block)
self.inner_implementation_action = block
@order_group.register(self)
@ordered = true
self
end
# @private
def negative_expectation_for?(message)
return false
end
# @private
def actual_received_count_matters?
@at_least || @at_most || @exactly
end
# @private
def increase_actual_received_count!
@actual_received_count += 1
end
private
def failed_fast?
@failed_fast
end
def set_expected_received_count(relativity, n)
@at_least = (relativity == :at_least)
@at_most = (relativity == :at_most)
@exactly = (relativity == :exactly)
@expected_received_count = case n
when Numeric then n
when :once then 1
when :twice then 2
end
end
def initial_implementation_action=(action)
implementation.initial_action = action
end
def inner_implementation_action=(action)
implementation.inner_action = action if action
end
def terminal_implementation_action=(action)
implementation.terminal_action = action
end
end
# @private
class NegativeMessageExpectation < MessageExpectation
# @private
def initialize(error_generator, expectation_ordering, expected_from, method_double, &implementation)
super(error_generator, expectation_ordering, expected_from, method_double, 0, {}, &implementation)
end
def and_return(*)
# no-op
# @deprecated and_return is not supported with negative message expectations.
RSpec::Mocks.warn_deprecation <<-MSG
DEPRECATION: `and_return` with `should_not_receive` is deprecated. Called from #{caller(0)[1]}
MSG
end
# @private
def negative_expectation_for?(message)
return @message == message
end
end
# Handles the implementation of an `and_yield` declaration.
# @private
class AndYieldImplementation
def initialize(args_to_yield, eval_context, error_generator)
@args_to_yield = args_to_yield
@eval_context = eval_context
@error_generator = error_generator
end
def arity
0
end
def call(&block)
return if @args_to_yield.empty? && @eval_context.nil?
@error_generator.raise_missing_block_error @args_to_yield unless block
value = nil
@args_to_yield.each do |args|
if block.arity > -1 && args.length != block.arity
@error_generator.raise_wrong_arity_error args, block.arity
end
value = @eval_context ? @eval_context.instance_exec(*args, &block) : block.call(*args)
end
value
end
end
# Handles the implementation of an `and_return` implementation.
# @private
class AndReturnImplementation
def initialize(values_to_return)
@values_to_return = values_to_return
end
def arity
0
end
def call(&block)
if @values_to_return.size > 1
@values_to_return.shift
else
@values_to_return.first
end
end
end
# Represents a configured implementation. Takes into account
# any number of sub-implementations.
# @private
class Implementation
attr_accessor :initial_action, :inner_action, :terminal_action
def call(*args, &block)
actions.map do |action|
action.arity.zero? ? action.call(&block) : action.call(*args, &block)
end.last
end
def present?
actions.any?
end
private
def actions
[initial_action, inner_action, terminal_action].compact
end
end
# Represents an `and_call_original` implementation.
# @private
class AndCallOriginalImplementation
def initialize(method)
@method = method
end
CannotModifyFurtherError = Class.new(StandardError)
def initial_action=(value)
raise cannot_modify_further_error
end
def inner_action=(value)
raise cannot_modify_further_error
end
def terminal_action=(value)
raise cannot_modify_further_error
end
def present?
true
end
def call(*args, &block)
@method.call(*args, &block)
end
private
def cannot_modify_further_error
CannotModifyFurtherError.new "This method has already been configured " +
"to call the original implementation, and cannot be modified further."
end
end
end
end