Class: RSpec::Matchers::DSL::Matcher

Inherits:

Object

• Object
• RSpec::Matchers::DSL::Matcher

show all

Includes:

RSpec::Matchers, Pretty

Defined in:

lib/rspec/matchers/matcher.rb

Overview

Constant Summary

PERSISTENT_INSTANCE_VARIABLES =

[
  :@name, :@declarations, :@diffable,
  :@match_block, :@match_for_should_not_block,
  :@expected_exception
].to_set

Instance Attribute Summary (collapse)

• - (Object) actual readonly

  Returns the value of attribute actual.

• - (Object) expected readonly

  Returns the value of attribute expected.

• - (Object) matcher_execution_context

  Returns the value of attribute matcher_execution_context.

• - (Object) rescued_exception readonly

  Returns the value of attribute rescued_exception.

Instance Method Summary (collapse)

• - (Object) chain(method, &block)

  Convenience for defining methods on this matcher to create a fluent interface.

• - (Object) description(&block)

  Customize the description to use for one-liners.

• - (Object) diffable

  Tells the matcher to diff the actual and expected values in the failure message.

• - (Boolean) diffable? private

  Used internally by objects returns by +should+ and +should_not+.

• - (Boolean) does_not_match?(actual) private

  Used internally by +should_not+.

• - (Object) failure_message_for_should {|Object| ... }

  Customize the failure messsage to use when this matcher is invoked with should.

• - (Object) failure_message_for_should_not {|Object| ... }

  Customize the failure messsage to use when this matcher is invoked with should_not.

• - (Object) for_expected(*expected) private
• - (Matcher) initialize(name, &declarations) constructor private

  A new instance of Matcher.

• - (Object) match {|Object| ... } (also: #match_for_should)

  Stores the block that is used to determine whether this matcher passes or fails.

• - (Object) match_for_should_not {|Object| ... }

  Use this to define the block for a negative expectation (should_not) when the positive and negative forms require different handling.

• - (Object) match_unless_raises(exception = Exception, &block)

  Use this instead of match when the block will raise an exception rather than returning false to indicate a failure.

• - (Boolean) matches?(actual) private

  Used internally by +should+ and +should_not+.

• - (Boolean) respond_to?(method, include_private = false)

Methods included from RSpec::Matchers

#be, #be_a, #be_a_kind_of, #be_an_instance_of, #be_close, #be_false, #be_nil, #be_true, #be_within, #change, clear_generated_description, configuration, #cover, #end_with, #eq, #eql, #equal, #exist, generated_description, #have, #have_at_least, #have_at_most, is_a_matcher?, #match_array, #raise_error, #respond_to, #satisfy, #start_with, #throw_symbol, #yield_control, #yield_successive_args, #yield_with_args, #yield_with_no_args

Methods included from Pretty

#_pretty_print, #expected_to_sentence, #name, #name_to_sentence, #split_words, #to_sentence, #to_word, #underscore

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# File 'lib/rspec/matchers/matcher.rb', line 16

def initialize(name, &declarations)
  @name         = name
  @declarations = declarations
  @actual       = nil
  @diffable     = false
  @expected_exception, @rescued_exception = nil, nil
  @match_for_should_not_block = nil
  @messages = {}
end

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# File 'lib/rspec/matchers/matcher.rb', line 229

def method_missing(method, *args, &block)
  if matcher_execution_context.respond_to?(method)
    matcher_execution_context.__send__ method, *args, &block
  else
    super(method, *args, &block)
  end
end

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# File 'lib/rspec/matchers/matcher.rb', line 12

def actual
  @actual
end

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# File 'lib/rspec/matchers/matcher.rb', line 12

def expected
  @expected
end

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# File 'lib/rspec/matchers/matcher.rb', line 13

def matcher_execution_context
  @matcher_execution_context
end

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# File 'lib/rspec/matchers/matcher.rb', line 12

def rescued_exception
  @rescued_exception
end

RSpec::Matchers.define :have_errors_on do |key|
  chain :with do |message|
    @message = message
  end

  match do |actual|
    actual.errors[key] == @message
  end
end

minor.should have_errors_on(:age).with("Not old enough to participate")

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# File 'lib/rspec/matchers/matcher.rb', line 201

def chain(method, &block)
  define_method method do |*args|
    block.call(*args)
    self
  end
end

RSpec::Matchers.define :qualify_for do |expected|
  match { ... }

  description do
    "qualify for #{expected}"
  end
end

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# File 'lib/rspec/matchers/matcher.rb', line 173

def description(&block)
  cache_or_call_cached(:description, &block)
end

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# File 'lib/rspec/matchers/matcher.rb', line 179

def diffable
  @diffable = true
end

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# File 'lib/rspec/matchers/matcher.rb', line 210

def diffable?
  @diffable
end

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# File 'lib/rspec/matchers/matcher.rb', line 216

def does_not_match?(actual)
  @actual = actual
  @match_for_should_not_block ?
    instance_exec(actual, &@match_for_should_not_block) :
    !matches?(actual)
end

RSpec::Matchers.define :have_strength do |expected|
  match { ... }

  failure_message_for_should do |actual|
    "Expected strength of #{expected}, but had #{actual.strength}"
  end
end

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# File 'lib/rspec/matchers/matcher.rb', line 136

def failure_message_for_should(&block)
  cache_or_call_cached(:failure_message_for_should, &block)
end

RSpec::Matchers.define :have_strength do |expected|
  match { ... }

  failure_message_for_should_not do |actual|
    "Expected not to have strength of #{expected}, but did"
  end
end

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# File 'lib/rspec/matchers/matcher.rb', line 156

def failure_message_for_should_not(&block)
  cache_or_call_cached(:failure_message_for_should_not, &block)
end

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# File 'lib/rspec/matchers/matcher.rb', line 33

def for_expected(*expected)
  @expected = expected
  dup.instance_eval do
    instance_variables.map {|ivar| ivar.intern}.each do |ivar|
      instance_variable_set(ivar, nil) unless (PERSISTENT_INSTANCE_VARIABLES + [:@expected]).include?(ivar)
    end
    @messages = {}
    instance_exec(*@expected, &@declarations)
    self
  end
end

RSpec::Matchers.define :be_even do
  match do |actual|
    actual.even?
  end
end

4.should be_even     # passes
3.should_not be_even # passes
3.should be_even     # fails
4.should_not be_even # fails

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# File 'lib/rspec/matchers/matcher.rb', line 88

def match(&block)
  @match_block = block
end

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# File 'lib/rspec/matchers/matcher.rb', line 100

def match_for_should_not(&block)
  @match_for_should_not_block = block
end

RSpec::Matchers.define :accept_as_valid do |candidate_address|
  match_unless_raises ValidationException do |validator|
    validator.validate(candidate_address)
  end
end

email_validator.should accept_as_valid("person@company.com")

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# File 'lib/rspec/matchers/matcher.rb', line 116

def match_unless_raises(exception=Exception, &block)
  @expected_exception = exception
  match(&block)
end

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# File 'lib/rspec/matchers/matcher.rb', line 47

def matches?(actual)
  @actual = actual
  if @expected_exception
    begin
      instance_exec(actual, &@match_block)
      true
    rescue @expected_exception => @rescued_exception
      false
    end
  else
    begin
      instance_exec(actual, &@match_block)
    rescue RSpec::Expectations::ExpectationNotMetError
      false
    end
  end
end

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# File 'lib/rspec/matchers/matcher.rb', line 223

def respond_to?(method, include_private=false)
  super || matcher_execution_context.respond_to?(method, include_private)
end