require File.join(File.dirname(__FILE__), "..", "test_helper")
require 'method_definer'
require 'mocha/expectation'
require 'mocha/sequence'
require 'execution_point'
require 'simple_counter'

class ExpectationTest < Test::Unit::TestCase
  
  include Mocha
  
  def new_expectation
    Expectation.new(nil, :expected_method)
  end
  
  def test_should_match_calls_to_same_method_with_any_parameters
    assert new_expectation.match?(:expected_method, 1, 2, 3)
  end
  
  def test_should_match_calls_to_same_method_with_exactly_zero_parameters
    expectation = new_expectation.with()
    assert expectation.match?(:expected_method)
  end
  
  def test_should_not_match_calls_to_same_method_with_more_than_zero_parameters
    expectation = new_expectation.with()
    assert !expectation.match?(:expected_method, 1, 2, 3)
  end
  
  def test_should_match_calls_to_same_method_with_expected_parameter_values
    expectation = new_expectation.with(1, 2, 3)
    assert expectation.match?(:expected_method, 1, 2, 3)
  end
  
  def test_should_match_calls_to_same_method_with_parameters_constrained_as_expected
    expectation = new_expectation.with() {|x, y, z| x + y == z}
    assert expectation.match?(:expected_method, 1, 2, 3)
  end
  
  def test_should_not_match_calls_to_different_method_with_parameters_constrained_as_expected
    expectation = new_expectation.with() {|x, y, z| x + y == z}
    assert !expectation.match?(:different_method, 1, 2, 3)
  end
  
  def test_should_not_match_calls_to_different_methods_with_no_parameters
    assert !new_expectation.match?(:unexpected_method)
  end
  
  def test_should_not_match_calls_to_same_method_with_too_few_parameters
    expectation = new_expectation.with(1, 2, 3)
    assert !expectation.match?(:unexpected_method, 1, 2)
  end
  
  def test_should_not_match_calls_to_same_method_with_too_many_parameters
    expectation = new_expectation.with(1, 2)
    assert !expectation.match?(:unexpected_method, 1, 2, 3)
  end
  
  def test_should_not_match_calls_to_same_method_with_unexpected_parameter_values
    expectation = new_expectation.with(1, 2, 3)
    assert !expectation.match?(:unexpected_method, 1, 0, 3)
  end
  
  def test_should_not_match_calls_to_same_method_with_parameters_not_constrained_as_expected
    expectation = new_expectation.with() {|x, y, z| x + y == z}
    assert !expectation.match?(:expected_method, 1, 0, 3)
  end
  
  def test_should_allow_invocations_until_expected_invocation_count_is_one_and_actual_invocation_count_would_be_two
    expectation = new_expectation.times(1)
    assert expectation.invocations_allowed?
    expectation.invoke
    assert !expectation.invocations_allowed?
  end
  
  def test_should_allow_invocations_until_expected_invocation_count_is_two_and_actual_invocation_count_would_be_three
    expectation = new_expectation.times(2)
    assert expectation.invocations_allowed?
    expectation.invoke
    assert expectation.invocations_allowed?
    expectation.invoke
    assert !expectation.invocations_allowed?
  end

  def test_should_allow_invocations_until_expected_invocation_count_is_a_range_from_two_to_three_and_actual_invocation_count_would_be_four
    expectation = new_expectation.times(2..3)
    assert expectation.invocations_allowed?
    expectation.invoke
    assert expectation.invocations_allowed?
    expectation.invoke
    assert expectation.invocations_allowed?
    expectation.invoke
    assert !expectation.invocations_allowed?
  end
  
  def test_should_store_provided_backtrace
    backtrace = Object.new
    expectation = Expectation.new(nil, :expected_method, backtrace)
    assert_equal backtrace, expectation.backtrace
  end
  
  def test_should_default_backtrace_to_caller
    execution_point = ExecutionPoint.current; expectation = Expectation.new(nil, :expected_method)
    assert_equal execution_point, ExecutionPoint.new(expectation.backtrace)
  end
  
  def test_should_not_yield
    yielded = false
    new_expectation.invoke() { yielded = true }
    assert_equal false, yielded
  end

  def test_should_yield_no_parameters
    expectation = new_expectation().yields()
    yielded_parameters = nil
    expectation.invoke() { |*parameters| yielded_parameters = parameters }
    assert_equal Array.new, yielded_parameters
  end

  def test_should_yield_with_specified_parameters
    expectation = new_expectation().yields(1, 2, 3)
    yielded_parameters = nil
    expectation.invoke() { |*parameters| yielded_parameters = parameters }
    assert_equal [1, 2, 3], yielded_parameters
  end

  def test_should_yield_different_parameters_on_consecutive_invocations
    expectation = new_expectation().yields(1, 2, 3).yields(4, 5)
    yielded_parameters = []
    expectation.invoke() { |*parameters| yielded_parameters << parameters }
    expectation.invoke() { |*parameters| yielded_parameters << parameters }
    assert_equal [[1, 2, 3], [4, 5]], yielded_parameters
  end
  
  def test_should_yield_multiple_times_for_single_invocation
    expectation = new_expectation().multiple_yields([1, 2, 3], [4, 5])
    yielded_parameters = []
    expectation.invoke() { |*parameters| yielded_parameters << parameters }
    assert_equal [[1, 2, 3], [4, 5]], yielded_parameters
  end

  def test_should_yield_multiple_times_for_first_invocation_and_once_for_second_invocation
    expectation = new_expectation().multiple_yields([1, 2, 3], [4, 5]).then.yields(6, 7)
    yielded_parameters = []
    expectation.invoke() { |*parameters| yielded_parameters << parameters }
    expectation.invoke() { |*parameters| yielded_parameters << parameters }
    assert_equal [[1, 2, 3], [4, 5], [6, 7]], yielded_parameters
  end

  def test_should_return_specified_value
    expectation = new_expectation.returns(99)
    assert_equal 99, expectation.invoke
  end
  
  def test_should_return_same_specified_value_multiple_times
    expectation = new_expectation.returns(99)
    assert_equal 99, expectation.invoke
    assert_equal 99, expectation.invoke
  end
  
  def test_should_return_specified_values_on_consecutive_calls
    expectation = new_expectation.returns(99, 100, 101)
    assert_equal 99, expectation.invoke
    assert_equal 100, expectation.invoke
    assert_equal 101, expectation.invoke
  end
  
  def test_should_return_specified_values_on_consecutive_calls_even_if_values_are_modified
    values = [99, 100, 101]
    expectation = new_expectation.returns(*values)
    values.shift
    assert_equal 99, expectation.invoke
    assert_equal 100, expectation.invoke
    assert_equal 101, expectation.invoke
  end
  
  def test_should_return_nil_by_default
    assert_nil new_expectation.invoke
  end
  
  def test_should_return_nil_if_no_value_specified
    expectation = new_expectation.returns()
    assert_nil expectation.invoke
  end
  
  def test_should_raise_runtime_exception
    expectation = new_expectation.raises
    assert_raise(RuntimeError) { expectation.invoke }
  end
  
  def test_should_raise_custom_exception
    exception = Class.new(Exception)
    expectation = new_expectation.raises(exception)
    assert_raise(exception) { expectation.invoke }
  end
  
  def test_should_raise_same_instance_of_custom_exception
    exception_klass = Class.new(StandardError)
    expected_exception = exception_klass.new
    expectation = new_expectation.raises(expected_exception)
    actual_exception = assert_raise(exception_klass) { expectation.invoke }
    assert_same expected_exception, actual_exception
  end
  
  def test_should_use_the_default_exception_message
    expectation = new_expectation.raises(Exception)
    exception = assert_raise(Exception) { expectation.invoke }
    assert_equal Exception.new.message, exception.message
  end
  
  def test_should_raise_custom_exception_with_message
    exception_msg = "exception message"
    expectation = new_expectation.raises(Exception, exception_msg)
    exception = assert_raise(Exception) { expectation.invoke }
    assert_equal exception_msg, exception.message
  end
  
  def test_should_return_values_then_raise_exception
    expectation = new_expectation.returns(1, 2).then.raises()
    assert_equal 1, expectation.invoke
    assert_equal 2, expectation.invoke
    assert_raise(RuntimeError) { expectation.invoke }
  end
  
  def test_should_raise_exception_then_return_values
    expectation = new_expectation.raises().then.returns(1, 2)
    assert_raise(RuntimeError) { expectation.invoke }
    assert_equal 1, expectation.invoke
    assert_equal 2, expectation.invoke
  end
  
  def test_should_verify_successfully_if_expected_call_was_made
    expectation = new_expectation
    expectation.invoke
    assert expectation.verified?
  end
  
  def test_should_not_verify_successfully_if_call_expected_once_but_invoked_twice
    expectation = new_expectation.once
    expectation.invoke
    expectation.invoke
    assert !expectation.verified?
  end

  def test_should_not_verify_successfully_if_call_expected_once_but_not_invoked
    expectation = new_expectation.once
    assert !expectation.verified?
  end

  def test_should_verify_successfully_if_call_expected_once_and_invoked_once
    expectation = new_expectation.once
    expectation.invoke
    assert expectation.verified?
  end

  def test_should_verify_successfully_if_expected_call_was_made_at_least_once
    expectation = new_expectation.at_least_once
    3.times {expectation.invoke}
    assert expectation.verified?
  end
  
  def test_should_not_verify_successfully_if_expected_call_was_not_made_at_least_once
    expectation = new_expectation.with(1, 2, 3).at_least_once
    assert !expectation.verified?
    assert_match(/expected at least once, not yet invoked/i, expectation.mocha_inspect)
  end
  
  def test_should_verify_successfully_if_expected_call_was_made_expected_number_of_times
    expectation = new_expectation.times(2)
    2.times {expectation.invoke}
    assert expectation.verified?
  end
  
  def test_should_not_verify_successfully_if_expected_call_was_made_too_few_times
    expectation = new_expectation.times(2)
    1.times {expectation.invoke}
    assert !expectation.verified?
    assert_match(/expected exactly twice, already invoked once/i, expectation.mocha_inspect)
  end
  
  def test_should_not_verify_successfully_if_expected_call_was_made_too_many_times
    expectation = new_expectation.times(2)
    3.times {expectation.invoke}
    assert !expectation.verified?
  end
  
  def test_should_increment_assertion_counter_for_expectation_because_it_does_need_verifyng
    expectation = new_expectation
    expectation.invoke
    assertion_counter = SimpleCounter.new
    expectation.verified?(assertion_counter)
    assert_equal 1, assertion_counter.count
  end
  
  def test_should_not_increment_assertion_counter_for_stub_because_it_does_not_need_verifying
    stub = Expectation.new(nil, :expected_method).at_least(0)
    assertion_counter = SimpleCounter.new
    stub.verified?(assertion_counter)
    assert_equal 0, assertion_counter.count
  end
  
  def test_should_store_backtrace_from_point_where_expectation_was_created
    execution_point = ExecutionPoint.current; expectation = Expectation.new(nil, :expected_method)
    assert_equal execution_point, ExecutionPoint.new(expectation.backtrace)
  end
  
  class FakeMock
    
    def initialize(name)
      @name = name
    end

    def mocha_inspect
      @name
    end
    
  end
  
  def test_should_raise_error_with_message_indicating_which_method_was_expected_to_be_called_on_which_mock_object_with_which_parameters_and_in_what_sequences
    mock = FakeMock.new('mock')
    sequence_one = Sequence.new('one')
    sequence_two = Sequence.new('two')
    expectation = Expectation.new(mock, :expected_method).with(1, 2, {'a' => true}, {:b => false}, [1, 2, 3]).in_sequence(sequence_one, sequence_two)
    assert !expectation.verified?
    assert_match "mock.expected_method(1, 2, {'a' => true}, {:b => false}, [1, 2, 3]); in sequence 'one'; in sequence 'two'", expectation.mocha_inspect
  end
  
  class FakeConstraint
    
    def initialize(allows_invocation_now)
      @allows_invocation_now = allows_invocation_now
    end
    
    def allows_invocation_now?
      @allows_invocation_now
    end
    
  end
  
  def test_should_be_in_correct_order_if_all_ordering_constraints_allow_invocation_now
    constraint_one = FakeConstraint.new(allows_invocation_now = true)
    constraint_two = FakeConstraint.new(allows_invocation_now = true)
    expectation = Expectation.new(nil, :method_one)
    expectation.add_ordering_constraint(constraint_one)
    expectation.add_ordering_constraint(constraint_two)
    assert expectation.in_correct_order?
  end
  
  def test_should_not_be_in_correct_order_if_one_ordering_constraint_does_not_allow_invocation_now
    constraint_one = FakeConstraint.new(allows_invocation_now = true)
    constraint_two = FakeConstraint.new(allows_invocation_now = false)
    expectation = Expectation.new(nil, :method_one)
    expectation.add_ordering_constraint(constraint_one)
    expectation.add_ordering_constraint(constraint_two)
    assert !expectation.in_correct_order?
  end
  
  def test_should_match_if_all_ordering_constraints_allow_invocation_now
    constraint_one = FakeConstraint.new(allows_invocation_now = true)
    constraint_two = FakeConstraint.new(allows_invocation_now = true)
    expectation = Expectation.new(nil, :method_one)
    expectation.add_ordering_constraint(constraint_one)
    expectation.add_ordering_constraint(constraint_two)
    assert expectation.match?(:method_one)
  end

  def test_should_not_match_if_one_ordering_constraints_does_not_allow_invocation_now
    constraint_one = FakeConstraint.new(allows_invocation_now = true)
    constraint_two = FakeConstraint.new(allows_invocation_now = false)
    expectation = Expectation.new(nil, :method_one)
    expectation.add_ordering_constraint(constraint_one)
    expectation.add_ordering_constraint(constraint_two)
    assert !expectation.match?(:method_one)
  end

  def test_should_not_be_satisfied_when_required_invocation_has_not_been_made
    expectation = Expectation.new(nil, :method_one).times(1)
    assert !expectation.satisfied?
  end

  def test_should_be_satisfied_when_required_invocation_has_been_made
    expectation = Expectation.new(nil, :method_one).times(1)
    expectation.invoke
    assert expectation.satisfied?
  end

  def test_should_not_be_satisfied_when_minimum_number_of_invocations_has_not_been_made
    expectation = Expectation.new(nil, :method_one).at_least(2)
    expectation.invoke
    assert !expectation.satisfied?
  end

  def test_should_be_satisfied_when_minimum_number_of_invocations_has_been_made
    expectation = Expectation.new(nil, :method_one).at_least(2)
    2.times { expectation.invoke }
    assert expectation.satisfied?
  end
  
  class FakeSequence
    
    attr_reader :expectations
    
    def initialize
      @expectations = []
    end
    
    def constrain_as_next_in_sequence(expectation)
      @expectations << expectation
    end
    
  end
  
  def test_should_tell_sequences_to_constrain_expectation_as_next_in_sequence
    sequence_one = FakeSequence.new
    sequence_two = FakeSequence.new
    expectation = Expectation.new(nil, :method_one)
    assert_equal expectation, expectation.in_sequence(sequence_one, sequence_two)
    assert_equal [expectation], sequence_one.expectations
    assert_equal [expectation], sequence_two.expectations
  end
  
  class FakeState
    
    def initialize
      @active = false
    end
    
    def activate
      @active = true
    end
    
    def active?
      @active
    end
    
  end
  
  def test_should_change_state_when_expectation_is_invoked
    state = FakeState.new
    expectation = Expectation.new(nil, :method_one)

    expectation.then(state)

    expectation.invoke
    assert state.active?
  end
  
  def test_should_match_when_state_is_active
    state = FakeState.new
    expectation = Expectation.new(nil, :method_one)

    expectation.when(state)
    assert !expectation.match?(:method_one)
    
    state.activate
    assert expectation.match?(:method_one)
  end
  
end
