create_matcher.feature

Feature: custom matcher shortcut

In order to express my domain clearly in my code examples
As an RSpec user
I want a shortcut for create custom matchers

Scenario: creating a matcher with default messages
  Given the following spec:
    """
    Spec::Matchers.create :be_a_multiple_of do |expected|
      match do |actual|
        actual % expected == 0
      end
    end

    describe 9 do
      it {should be_a_multiple_of(3)}
    end

    describe 9 do
      it {should_not be_a_multiple_of(4)}
    end

    # fail intentionally to generate expected output
    describe 9 do
      it {should be_a_multiple_of(4)}
    end

    # fail intentionally to generate expected output
    describe 9 do
      it {should_not be_a_multiple_of(3)}
    end

    """
  When I run it with the spec command --format specdoc
  Then the exit code should be 256

  And the stdout should match "should be a multiple of 3"
  And the stdout should match "should not be a multiple of 4"
  And the stdout should match "should be a multiple of 4 (FAILED - 1)"
  And the stdout should match "should not be a multiple of 3 (FAILED - 2)"

  And the stdout should match "4 examples, 2 failures"
  And the stdout should match "expected 9 to be a multiple of 4"
  And the stdout should match "expected 9 not to be a multiple of 3"

Scenario: overriding the failure_message_for_should
  Given the following spec:
    """
    Spec::Matchers.create :be_a_multiple_of do |expected|
      match do |actual|
        actual % expected == 0
      end
      failure_message_for_should do |actual|
        "expected that #{actual} would be a multiple of #{expected}"
      end
    end

    # fail intentionally to generate expected output
    describe 9 do
      it {should be_a_multiple_of(4)}
    end
    """
  When I run it with the spec command
  Then the exit code should be 256
  And the stdout should match "1 example, 1 failure"
  And the stdout should match "expected that 9 would be a multiple of 4"

Scenario: overriding the failure_message_for_should_not
  Given the following spec:
    """
    Spec::Matchers.create :be_a_multiple_of do |expected|
      match do |actual|
        actual % expected == 0
      end
      failure_message_for_should_not do |actual|
        "expected that #{actual} would not be a multiple of #{expected}"
      end
    end

    # fail intentionally to generate expected output
    describe 9 do
      it {should_not be_a_multiple_of(3)}
    end
    """
  When I run it with the spec command
  Then the exit code should be 256
  And the stdout should match "1 example, 1 failure"
  And the stdout should match "expected that 9 would not be a multiple of 3"

Scenario: overriding the description
  Given the following spec:
    """
    Spec::Matchers.create :be_a_multiple_of do |expected|
      match do |actual|
        actual % expected == 0
      end
      description do
        "be multiple of #{expected}"
      end
    end

    describe 9 do
      it {should be_a_multiple_of(3)}
    end

    describe 9 do
      it {should_not be_a_multiple_of(4)}
    end
    """
  When I run it with the spec command --format specdoc
  Then the exit code should be 0
  And the stdout should match "2 examples, 0 failures"
  And the stdout should match "should be multiple of 3"
  And the stdout should match "should not be multiple of 4"