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In Files

  • minitest/unit.rb

MiniTest::Assertions

MiniTest Assertions. All assertion methods accept a msg which is printed if the assertion fails.

Public Instance Methods

assert(test, msg = nil) click to toggle source

Fails unless test is a true value.

 
               # File minitest/unit.rb, line 80
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
            
assert_block(msg = nil) click to toggle source

Fails unless the block returns a true value.

 
               # File minitest/unit.rb, line 93
def assert_block msg = nil
  assert yield, "Expected block to return true value."
end
            
assert_empty(obj, msg = nil) click to toggle source

Fails unless obj is empty.

 
               # File minitest/unit.rb, line 100
def assert_empty obj, msg = nil
  msg = message(msg) { "Expected #{mu_pp(obj)} to be empty" }
  assert_respond_to obj, :empty?
  assert obj.empty?, msg
end
            
assert_equal(exp, act, msg = nil) click to toggle source

Fails unless exp == act.

For floats use #assert_in_delta

 
               # File minitest/unit.rb, line 111
def assert_equal exp, act, msg = nil
  msg = message(msg) { "Expected #{mu_pp(exp)}, not #{mu_pp(act)}" }
  assert(exp == act, msg)
end
            
assert_in_delta(exp, act, delta = 0.001, msg = nil) click to toggle source

For comparing Floats. Fails unless exp and act are within delta of each other.

assert_in_delta Math::PI, (22.0 / 7.0), 0.01
 
               # File minitest/unit.rb, line 122
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
            
assert_in_epsilon(a, b, epsilon = 0.001, msg = nil) click to toggle source

For comparing Floats. Fails unless exp and act have a relative error less than epsilon.

 
               # File minitest/unit.rb, line 132
def assert_in_epsilon a, b, epsilon = 0.001, msg = nil
  assert_in_delta a, b, [a, b].min * epsilon, msg
end
            
assert_includes(collection, obj, msg = nil) click to toggle source

Fails unless collection includes obj.

 
               # File minitest/unit.rb, line 139
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
            
assert_instance_of(cls, obj, msg = nil) click to toggle source

Fails unless obj is an instace of cls.

 
               # File minitest/unit.rb, line 150
def assert_instance_of cls, obj, msg = nil
  msg = message(msg) {
    "Expected #{mu_pp(obj)} to be an instance of #{cls}, not #{obj.class}"
  }

  assert obj.instance_of?(cls), msg
end
            
assert_kind_of(cls, obj, msg = nil) click to toggle source

Fails unless obj is a kind of cls.

 
               # File minitest/unit.rb, line 161
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}" }

  assert obj.kind_of?(cls), msg
end
            
assert_match(exp, act, msg = nil) click to toggle source

Fails unless exp is =~ act.

 
               # File minitest/unit.rb, line 171
def assert_match exp, act, msg = nil
  msg = message(msg) { "Expected #{mu_pp(exp)} to match #{mu_pp(act)}" }
  assert_respond_to act, :"=~"
  exp = /#{Regexp.escape exp}/ if String === exp && String === act
  assert exp =~ act, msg
end
            
assert_nil(obj, msg = nil) click to toggle source

Fails unless obj is nil

 
               # File minitest/unit.rb, line 181
def assert_nil obj, msg = nil
  msg = message(msg) { "Expected #{mu_pp(obj)} to be nil" }
  assert obj.nil?, msg
end
            
assert_operator(o1, op, o2, msg = nil) click to toggle source

For testing equality operators and so-forth.

assert_operator 5, :<=, 4
 
               # File minitest/unit.rb, line 191
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
            
assert_raises(*exp) click to toggle source

Fails unless the block raises one of exp

 
               # File minitest/unit.rb, line 199
def assert_raises *exp
  msg = String === exp.last ? exp.pop : nil
  msg = msg.to_s + "\n" if msg
  should_raise = false
  begin
    yield
    should_raise = true
  rescue MiniTest::Skip => e
    details = "#{msg}#{mu_pp(exp)} exception expected, not"

    if exp.include? MiniTest::Skip then
      return e
    else
      raise e
    end
  rescue Exception => e
    details = "#{msg}#{mu_pp(exp)} exception expected, not"
    assert(exp.any? { |ex|
             ex.instance_of?(Module) ? e.kind_of?(ex) : ex == e.class
           }, exception_details(e, details))

    return e
  end

  exp = exp.first if exp.size == 1
  flunk "#{msg}#{mu_pp(exp)} expected but nothing was raised." if
    should_raise
end
            
assert_respond_to(obj, meth, msg = nil) click to toggle source

Fails unless obj responds to meth.

 
               # File minitest/unit.rb, line 231
def assert_respond_to obj, meth, msg = nil
  msg = message(msg) {
      "Expected #{mu_pp(obj)} (#{obj.class}) to respond to ##{meth}"
    }
  assert obj.respond_to?(meth), msg
end
            
assert_same(exp, act, msg = nil) click to toggle source

Fails unless exp and act are equal?

 
               # File minitest/unit.rb, line 241
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 (oid=%d) to be the same as %s (oid=%d)" % data
  }
  assert exp.equal?(act), msg
end
            
assert_send(send_ary, m = nil) click to toggle source

send_ary is a receiver, message and arguments.

Fails unless the call returns a true value TODO: I should prolly remove this from specs

 
               # File minitest/unit.rb, line 255
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
            
assert_throws(sym, msg = nil) click to toggle source

Fails unless the block throws sym

 
               # File minitest/unit.rb, line 265
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
            
capture_io() click to toggle source

Captures $stdout and $stderr into strings:

out, err = capture_io do
  warn "You did a bad thing"
end

assert_match %r%bad%, err
 
               # File minitest/unit.rb, line 291
def capture_io
  require 'stringio'

  orig_stdout, orig_stderr         = $stdout, $stderr
  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
            
exception_details(e, msg) click to toggle source

Returns details for exception e

 
               # File minitest/unit.rb, line 309
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
            
flunk(msg = nil) click to toggle source

Fails with msg

 
               # File minitest/unit.rb, line 316
def flunk msg = nil
  msg ||= "Epic Fail!"
  assert false, msg
end
            
message(msg = nil, &default) click to toggle source

Returns a proc that will output msg along with the default message.

 
               # File minitest/unit.rb, line 324
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
            
mu_pp(obj) click to toggle source

#mu_pp gives a human-readable version of obj. By default inspect is called. You can override this to use pretty_print if you want.

 
               # File minitest/unit.rb, line 63
def mu_pp obj
  s = obj.inspect
  s = s.force_encoding(Encoding.default_external) if defined? Encoding
  s
end
            
pass(msg = nil) click to toggle source

used for counting assertions

 
               # File minitest/unit.rb, line 340
def pass msg = nil
  assert true
end
            
refute(test, msg = nil) click to toggle source

Fails if test is a true value

 
               # File minitest/unit.rb, line 347
def refute test, msg = nil
  msg ||= "Failed refutation, no message given"
  not assert(! test, msg)
end
            
refute_empty(obj, msg = nil) click to toggle source

Fails if obj is empty.

 
               # File minitest/unit.rb, line 355
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
            
refute_equal(exp, act, msg = nil) click to toggle source

Fails if exp == act.

For floats use refute_in_delta.

 
               # File minitest/unit.rb, line 366
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
            
refute_in_delta(exp, act, delta = 0.001, msg = nil) click to toggle source

For comparing Floats. Fails if exp is within delta of act

refute_in_delta Math::PI, (22.0 / 7.0)
 
               # File minitest/unit.rb, line 378
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
            
refute_in_epsilon(a, b, epsilon = 0.001, msg = nil) click to toggle source

For comparing Floats. Fails if exp and act have a relative error less than epsilon.

 
               # File minitest/unit.rb, line 390
def refute_in_epsilon a, b, epsilon = 0.001, msg = nil
  refute_in_delta a, b, a * epsilon, msg
end
            
refute_includes(collection, obj, msg = nil) click to toggle source

Fails if collection includes obj

 
               # File minitest/unit.rb, line 397
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
            
refute_instance_of(cls, obj, msg = nil) click to toggle source

Fails if obj is an instance of cls

 
               # File minitest/unit.rb, line 408
def refute_instance_of cls, obj, msg = nil
  msg = message(msg) {
    "Expected #{mu_pp(obj)} to not be an instance of #{cls}"
  }
  refute obj.instance_of?(cls), msg
end
            
refute_kind_of(cls, obj, msg = nil) click to toggle source

Fails if obj is a kind of cls

 
               # File minitest/unit.rb, line 418
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}" }
  refute obj.kind_of?(cls), msg
end
            
refute_match(exp, act, msg = nil) click to toggle source

Fails if exp =~ act

 
               # File minitest/unit.rb, line 426
def refute_match exp, act, msg = nil
  msg = message(msg) { "Expected #{mu_pp(exp)} to not match #{mu_pp(act)}" }
  assert_respond_to act, :"=~"
  exp = (/#{Regexp.escape exp}/) if String === exp and String === act
  refute exp =~ act, msg
end
            
refute_nil(obj, msg = nil) click to toggle source

Fails if obj is nil.

 
               # File minitest/unit.rb, line 436
def refute_nil obj, msg = nil
  msg = message(msg) { "Expected #{mu_pp(obj)} to not be nil" }
  refute obj.nil?, msg
end
            
refute_operator(o1, op, o2, msg = nil) click to toggle source

Fails if o1 is not op o2 nil. eg:

refute_operator 1, :>, 2 #=> pass
refute_operator 1, :<, 2 #=> fail
 
               # File minitest/unit.rb, line 447
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
            
refute_respond_to(obj, meth, msg = nil) click to toggle source

Fails if obj responds to the message meth.

 
               # File minitest/unit.rb, line 457
def refute_respond_to obj, meth, msg = nil
  msg = message(msg) { "Expected #{mu_pp(obj)} to not respond to #{meth}" }

  refute obj.respond_to?(meth), msg
end
            
refute_same(exp, act, msg = nil) click to toggle source

Fails if exp is the same (by object identity) as act.

 
               # File minitest/unit.rb, line 466
def refute_same exp, act, msg = nil
  msg = message(msg) {
    data = [mu_pp(act), act.object_id, mu_pp(exp), exp.object_id]
    "Expected %s (oid=%d) to not be the same as %s (oid=%d)" % data
  }
  refute exp.equal?(act), msg
end
            
skip(msg = nil, bt = caller) click to toggle source

Skips the current test. Gets listed at the end of the run but doesn’t cause a failure exit code.

 
               # File minitest/unit.rb, line 478
def skip msg = nil, bt = caller
  msg ||= "Skipped, no message given"
  raise MiniTest::Skip, msg, bt
end
            

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