module Shoulda::Context::Assertions

def assert_accepts(matcher, target, options = {})

#matches?
Asserts that the given matcher returns true when +target+ is passed to 
def assert_accepts(matcher, target, options = {})
  if matcher.respond_to?(:in_context)
    matcher.in_context(self)
  end
  if matcher.matches?(target)
    safe_assert_block { true }
    if options[:message]
      assert_match options[:message], matcher.failure_message_when_negated
    end
  else
    safe_assert_block(matcher.failure_message) { false }
  end
end

def assert_contains(collection, x, extra_msg = "")

assert_contains(['a', '1'], /not there/) => fails
assert_contains(['a', '1'], 'a') => passes
assert_contains(['a', '1'], /\d/) => passes

at least one element from the collection matches x. +extra_msg+ is appended to the error message if the assertion fails.
Asserts that the given collection contains item x. If x is a regular expression, ensure that 
def assert_contains(collection, x, extra_msg = "")
  collection = Array(collection)
  msg = "#{x.inspect} not found in #{collection.to_a.inspect} #{extra_msg}"
  case x
  when Regexp
    assert(collection.detect { |e| e =~ x }, msg)
  else
    assert(collection.include?(x), msg)
  end
end

def assert_does_not_contain(collection, x, extra_msg = "")

none of the elements from the collection match x.
Asserts that the given collection does not contain item x. If x is a regular expression, ensure that 
def assert_does_not_contain(collection, x, extra_msg = "")
  collection = Array(collection)
  msg = "#{x.inspect} found in #{collection.to_a.inspect} " + extra_msg
  case x
  when Regexp
    assert(!collection.detect { |e| e =~ x }, msg)
  else
    assert(!collection.include?(x), msg)
  end
end

def assert_rejects(matcher, target, options = {})

#does_not_match? is not implemented
#does_not_match? or false when +target+ is passed to #matches? if
Asserts that the given matcher returns true when +target+ is passed to 
def assert_rejects(matcher, target, options = {})
  if matcher.respond_to?(:in_context)
    matcher.in_context(self)
  end
  not_match =
    if matcher.respond_to?(:does_not_match?)
      matcher.does_not_match?(target)
    else
      !matcher.matches?(target)
    end
  if not_match
    safe_assert_block { true }
    if options[:message]
      assert_match options[:message], matcher.failure_message
    end
  else
    safe_assert_block(matcher.failure_message_when_negated) { false }
  end
end

def assert_same_elements(a1, a2, msg = nil)

assert_same_elements([:a, :b, :c], [:c, :a, :b]) => passes)

Asserts that two arrays contain the same elements, the same number of times. Essentially ==, but unordered. 
def assert_same_elements(a1, a2, msg = nil)
  [:select, :inject, :size].each do |m|
    [a1, a2].each {|a| assert_respond_to(a, m, "Are you sure that #{a.inspect} is an array?  It doesn't respond to #{m}.") }
  end
  assert a1h = a1.inject({}) { |h,e| h[e] ||= a1.select { |i| i == e }.size; h }
  assert a2h = a2.inject({}) { |h,e| h[e] ||= a2.select { |i| i == e }.size; h }
  assert_equal(a1h, a2h, msg)
end

def safe_assert_block(message = "assert_block failed.", &block) 

def safe_assert_block(message = "assert_block failed.", &block)
  if respond_to?(:assert_block)
    assert_block message, &block
  else
    assert yield, message
  end
end