module MiniTest::Assertions

def _assertions
  @_assertions ||= 0
end

def _assertions= n
  @_assertions = n
end

def assert test, msg = nil
  msg ||= "Failed assertion, no message given."
  self._assertions += 1
  unless test then
    msg = msg.call if Proc === msg
    raise MiniTest::Assertion, msg
  end
  true
end

def assert_block msg = nil
  msg = message(msg) { "Expected block to return true value" }
  assert yield, msg
end

def assert_empty obj, msg = nil
  msg = message(msg) { "Expected #{obj.inspect} to be empty" }
  assert_respond_to obj, :empty?
  assert obj.empty?, msg
end

def assert_equal exp, act, msg = nil
  msg = message(msg) { "Expected #{mu_pp(exp)}, not #{mu_pp(act)}" }
  assert(exp == act, msg)
end

def assert_in_delta exp, act, delta = 0.001, msg = nil
  n = (exp - act).abs
  msg = message(msg) { "Expected #{exp} - #{act} (#{n}) to be < #{delta}" }
  assert delta > n, msg
end

def assert_in_epsilon a, b, epsilon = 0.001, msg = nil
  assert_in_delta a, b, [a, b].min * epsilon, msg
end

def assert_includes collection, obj, msg = nil
  msg = message(msg) { "Expected #{mu_pp(collection)} to include #{mu_pp(obj)}" }
  assert_respond_to collection, :include?
  assert collection.include?(obj), msg
end

def assert_instance_of cls, obj, msg = nil
  msg = message(msg) { "Expected #{mu_pp(obj)} to be an instance of #{cls}, not #{obj.class}" }
  flip = (Module === obj) && ! (Module === cls) # HACK for specs
  obj, cls = cls, obj if flip
  assert cls === obj, msg
end

def assert_kind_of cls, obj, msg = nil # TODO: merge with instance_of
  msg = message(msg) {
    "Expected #{mu_pp(obj)} to be a kind of #{cls}, not #{obj.class}" }
  flip = (Module === obj) && ! (Module === cls) # HACK for specs
  obj, cls = cls, obj if flip
  assert obj.kind_of?(cls), msg
end

def assert_match exp, act, msg = nil
  msg = message(msg) { "Expected #{mu_pp(act)} to match #{mu_pp(exp)}" }
  assert_respond_to act, :"=~"
  (exp = /#{exp}/) if String === exp && String === act
  assert act =~ exp, msg
end

def assert_nil obj, msg = nil
  msg = message(msg) { "Expected #{mu_pp(obj)} to be nil" }
  assert obj.nil?, msg
end

def assert_operator o1, op, o2, msg = nil
  msg = message(msg) { "Expected #{mu_pp(o1)} to be #{op} #{mu_pp(o2)}" }
  assert o1.__send__(op, o2), msg
end

def assert_raises *exp
  msg = String === exp.last ? exp.pop : nil
  should_raise = false
  begin
    yield
    should_raise = true
  rescue Exception => e
    assert_includes(exp, e.class, exception_details(e, "<#{mu_pp(exp)}> exception expected, not"))
    return e
  end
  exp = exp.first if exp.size == 1
  flunk "#{mu_pp(exp)} expected but nothing was raised." if should_raise
end

def assert_respond_to obj, meth, msg = nil
  msg = message(msg) {
      "Expected #{mu_pp(obj)} (#{obj.class}) to respond to ##{meth}"
    }
  flip = (Symbol === obj) && ! (Symbol === meth) # HACK for specs
  obj, meth = meth, obj if flip
  assert obj.respond_to?(meth), msg
end

def assert_same exp, act, msg = nil
  msg = message(msg) {
    data = [mu_pp(act), act.object_id, mu_pp(exp), exp.object_id]
    "Expected %s (0x%x) to be the same as %s (0x%x)" % data
  }
  assert exp.equal?(act), msg
end

def assert_send send_ary, m = nil
  recv, msg, *args = send_ary
  m = message(m) {
    "Expected #{mu_pp(recv)}.#{msg}(*#{mu_pp(args)}) to return true" }
  assert recv.__send__(msg, *args), m
end

def assert_throws sym, msg = nil
  default = "Expected #{mu_pp(sym)} to have been thrown"
  caught = true
  catch(sym) do
    begin
      yield
    rescue ArgumentError => e     # 1.9 exception
      default += ", not #{e.message.split(/ /).last}"
    rescue NameError => e         # 1.8 exception
      default += ", not #{e.name.inspect}"
    end
    caught = false
  end
  assert caught, message(msg) { default }
end

def capture_io
  require 'stringio'
  orig_stdout, orig_stderr         = $stdout.dup, $stderr.dup
  captured_stdout, captured_stderr = StringIO.new, StringIO.new
  $stdout, $stderr                 = captured_stdout, captured_stderr
  yield
  return captured_stdout.string, captured_stderr.string
ensure
  $stdout = orig_stdout
  $stderr = orig_stderr
end

def exception_details e, msg
  "#{msg}\nClass: <#{e.class}>\nMessage: <#{e.message.inspect}>\n---Backtrace---\n#{MiniTest::filter_backtrace(e.backtrace).join("\n")}\n---------------"
end

def flunk msg = nil
  msg ||= "Epic Fail!"
  assert false, msg
end

def message msg = nil, &default
  proc {
    if msg then
      msg = msg.to_s unless String === msg
      msg += '.' unless msg.empty?
      msg += "\n#{default.call}."
      msg.strip
    else
      "#{default.call}."
    end
  }
end

def mu_pp(obj)
  s = obj.inspect
  s = s.force_encoding(Encoding.default_external) if defined? Encoding
  s
end

def pass msg = nil
  assert true
end

def refute test, msg = nil
  msg ||= "Failed refutation, no message given"
  not assert(! test, msg)
end

def refute_empty obj, msg = nil
  msg = message(msg) { "Expected #{obj.inspect} to not be empty" }
  assert_respond_to obj, :empty?
  refute obj.empty?, msg
end

def refute_equal exp, act, msg = nil
  msg = message(msg) { "Expected #{mu_pp(act)} to not be equal to #{mu_pp(exp)}" }
  refute exp == act, msg
end

def refute_in_delta exp, act, delta = 0.001, msg = nil
  n = (exp - act).abs
  msg = message(msg) { "Expected #{exp} - #{act} (#{n}) to not be < #{delta}" }
  refute delta > n, msg
end

def refute_in_epsilon a, b, epsilon = 0.001, msg = nil
  refute_in_delta a, b, a * epsilon, msg
end

def refute_includes collection, obj, msg = nil
  msg = message(msg) { "Expected #{mu_pp(collection)} to not include #{mu_pp(obj)}" }
  assert_respond_to collection, :include?
  refute collection.include?(obj), msg
end

def refute_instance_of cls, obj, msg = nil
  msg = message(msg) { "Expected #{mu_pp(obj)} to not be an instance of #{cls}" }
  flip = (Module === obj) && ! (Module === cls) # HACK for specs
  obj, cls = cls, obj if flip
  refute cls === obj, msg
end

def refute_kind_of cls, obj, msg = nil # TODO: merge with instance_of
  msg = message(msg) { "Expected #{mu_pp(obj)} to not be a kind of #{cls}" }
  flip = (Module === obj) && ! (Module === cls) # HACK for specs
  obj, cls = cls, obj if flip
  refute obj.kind_of?(cls), msg
end

def refute_match exp, act, msg = nil
  msg = message(msg) { "Expected #{mu_pp(act)} to not match #{mu_pp(exp)}" }
  refute act =~ exp, msg
end

def refute_nil obj, msg = nil
  msg = message(msg) { "Expected #{mu_pp(obj)} to not be nil" }
  refute obj.nil?, msg
end

def refute_operator o1, op, o2, msg = nil
  msg = message(msg) { "Expected #{mu_pp(o1)} to not be #{op} #{mu_pp(o2)}" }
  refute o1.__send__(op, o2), msg
end

def refute_respond_to obj, meth, msg = nil
  msg = message(msg) { "Expected #{mu_pp(obj)} to not respond to #{meth}" }
  flip = (Symbol === obj) && ! (Symbol === meth) # HACK for specs
  obj, meth = meth, obj if flip
  refute obj.respond_to?(meth), msg
end

def refute_same exp, act, msg = nil
  msg = message(msg) { "Expected #{mu_pp(act)} to not be the same as #{mu_pp(exp)}" }
  refute exp.equal?(act), msg
end

def skip msg = nil
  msg ||= "Skipped, no message given"
  raise MiniTest::Skip, msg
end