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Minitest Assertions.  All assertion methods
accept a msg which is printed if the assertion fails.
Protocol: Nearly everything here boils up to assert, which
expects to be able to increment an instance accessor named
assertions. This is not provided by Assertions and must be provided by the thing
including Assertions. See Minitest::Runnable
for an example.
Returns the diff command to use in diff. Tries to intelligently figure out what diff to use.
 
               # File minitest-5.14.2/lib/minitest/assertions.rb, line 28
def self.diff
  return @diff if defined? @diff
  @diff = if (RbConfig::CONFIG["host_os"] =~ /mswin|mingw/ &&
              system("diff.exe", __FILE__, __FILE__)) then
            "diff.exe -u"
          elsif system("gdiff", __FILE__, __FILE__)
            "gdiff -u" # solaris and kin suck
          elsif system("diff", __FILE__, __FILE__)
            "diff -u"
          else
            nil
          end
end
             
            Set the diff command to use in diff.
 
               # File minitest-5.14.2/lib/minitest/assertions.rb, line 46
def self.diff= o
  @diff = o
end
             
            Fails unless test is truthy.
 
               # File minitest-5.14.2/lib/minitest/assertions.rb, line 177
def assert test, msg = nil
  self.assertions += 1
  unless test then
    msg ||= "Expected #{mu_pp test} to be truthy."
    msg = msg.call if Proc === msg
    raise Minitest::Assertion, msg
  end
  true
end
             
            Fails unless obj is empty.
 
               # File minitest-5.14.2/lib/minitest/assertions.rb, line 194
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
             
            Fails unless exp == act printing the difference between the
two, if possible.
If there is no visible difference but the assertion fails, you should suspect that your #== is buggy, or your inspect output is missing crucial details. For nicer structural diffing, set Minitest::Test.make_my_diffs_pretty!
For floats use assert_in_delta.
See also: ::diff
 
               # File minitest-5.14.2/lib/minitest/assertions.rb, line 215
def assert_equal exp, act, msg = nil
  msg = message(msg, E) { diff exp, act }
  result = assert exp == act, msg
  if nil == exp then
    if Minitest::VERSION =~ /^6/ then
      refute_nil exp, "Use assert_nil if expecting nil."
    else
      where = Minitest.filter_backtrace(caller).first
      where = where.split(/:in /, 2).first # clean up noise
      warn "DEPRECATED: Use assert_nil if expecting nil from #{where}. This will fail in Minitest 6."
    end
  end
  result
end
             
            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-5.14.2/lib/minitest/assertions.rb, line 239
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
             
            For comparing Floats.  Fails unless exp and act
have a relative error less than epsilon.
 
               # File minitest-5.14.2/lib/minitest/assertions.rb, line 251
def assert_in_epsilon exp, act, epsilon = 0.001, msg = nil
  assert_in_delta exp, act, [exp.abs, act.abs].min * epsilon, msg
end
             
            Fails unless collection includes obj.
 
               # File minitest-5.14.2/lib/minitest/assertions.rb, line 258
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
             
            Fails unless obj is an instance of cls.
 
               # File minitest-5.14.2/lib/minitest/assertions.rb, line 269
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
             
            Fails unless obj is a kind of cls.
 
               # File minitest-5.14.2/lib/minitest/assertions.rb, line 280
def assert_kind_of cls, obj, msg = nil
  msg = message(msg) {
    "Expected #{mu_pp(obj)} to be a kind of #{cls}, not #{obj.class}" }
  assert obj.kind_of?(cls), msg
end
             
            Fails unless matcher =~ obj.
 
               # File minitest-5.14.2/lib/minitest/assertions.rb, line 290
def assert_match matcher, obj, msg = nil
  msg = message(msg) { "Expected #{mu_pp matcher} to match #{mu_pp obj}" }
  assert_respond_to matcher, :"=~"
  matcher = Regexp.new Regexp.escape matcher if String === matcher
  assert matcher =~ obj, msg
end
             
            Assert that the mock verifies correctly.
 
               # File minitest-5.14.2/lib/minitest/mock.rb, line 184
def assert_mock mock
  assert mock.verify
end
             
            Fails unless obj is nil
 
               # File minitest-5.14.2/lib/minitest/assertions.rb, line 300
def assert_nil obj, msg = nil
  msg = message(msg) { "Expected #{mu_pp(obj)} to be nil" }
  assert obj.nil?, msg
end
             
            For testing with binary operators. Eg:
assert_operator 5, :<=, 4
 
               # File minitest-5.14.2/lib/minitest/assertions.rb, line 310
def assert_operator o1, op, o2 = UNDEFINED, msg = nil
  return assert_predicate o1, op, msg if UNDEFINED == o2
  msg = message(msg) { "Expected #{mu_pp(o1)} to be #{op} #{mu_pp(o2)}" }
  assert o1.__send__(op, o2), msg
end
             
            Fails if stdout or stderr do not output the expected results. Pass in nil if you don't care about that streams output. Pass in “” if you require it to be silent. Pass in a regexp if you want to pattern match.
assert_output(/hey/) { method_with_output }
NOTE: this uses capture_io, not capture_subprocess_io.
See also: assert_silent
 
               # File minitest-5.14.2/lib/minitest/assertions.rb, line 328
def assert_output stdout = nil, stderr = nil
  flunk "assert_output requires a block to capture output." unless
    block_given?
  out, err = capture_io do
    yield
  end
  err_msg = Regexp === stderr ? :assert_match : :assert_equal if stderr
  out_msg = Regexp === stdout ? :assert_match : :assert_equal if stdout
  y = send err_msg, stderr, err, "In stderr" if err_msg
  x = send out_msg, stdout, out, "In stdout" if out_msg
  (!stdout || x) && (!stderr || y)
rescue Assertion
  raise
rescue => e
  raise UnexpectedError, e
end
             
            Fails unless path exists.
 
               # File minitest-5.14.2/lib/minitest/assertions.rb, line 352
def assert_path_exists path, msg = nil
  msg = message(msg) { "Expected path '#{path}' to exist" }
  assert File.exist?(path), msg
end
             
            For testing with predicates. Eg:
assert_predicate str, :empty?
This is really meant for specs and is front-ended by #assert_operator:
str.must_be :empty?
 
               # File minitest-5.14.2/lib/minitest/assertions.rb, line 366
def assert_predicate o1, op, msg = nil
  msg = message(msg) { "Expected #{mu_pp(o1)} to be #{op}" }
  assert o1.__send__(op), msg
end
             
            Fails unless the block raises one of exp. Returns the
exception matched so you can check the message, attributes, etc.
exp takes an optional message on the end to help explain
failures and defaults to StandardError if no exception class is passed. Eg:
assert_raises(CustomError) { method_with_custom_error }
With custom error message:
assert_raises(CustomError, 'This should have raised CustomError') { method_with_custom_error }
Using the returned object:
error = assert_raises(CustomError) do raise CustomError, 'This is really bad' end assert_equal 'This is really bad', error.message
 
               # File minitest-5.14.2/lib/minitest/assertions.rb, line 393
def assert_raises *exp
  flunk "assert_raises requires a block to capture errors." unless
    block_given?
  msg = "#{exp.pop}.\n" if String === exp.last
  exp << StandardError if exp.empty?
  begin
    yield
  rescue *exp => e
    pass # count assertion
    return e
  rescue Minitest::Assertion # incl Skip & UnexpectedError
    # don't count assertion
    raise
  rescue SignalException, SystemExit
    raise
  rescue Exception => e
    flunk proc {
      exception_details(e, "#{msg}#{mu_pp(exp)} exception expected, not")
    }
  end
  exp = exp.first if exp.size == 1
  flunk "#{msg}#{mu_pp(exp)} expected but nothing was raised."
end
             
            Fails unless obj responds to meth.
 
               # File minitest-5.14.2/lib/minitest/assertions.rb, line 424
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
             
            Fails unless exp and act are equal?
 
               # File minitest-5.14.2/lib/minitest/assertions.rb, line 434
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
             
            send_ary is a receiver, message and arguments.
Fails unless the call returns a true value
 
               # File minitest-5.14.2/lib/minitest/assertions.rb, line 447
def assert_send send_ary, m = nil
  where = Minitest.filter_backtrace(caller).first
  where = where.split(/:in /, 2).first # clean up noise
  warn "DEPRECATED: assert_send. From #{where}"
  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
             
            Fails if the block outputs anything to stderr or stdout.
See also: assert_output
 
               # File minitest-5.14.2/lib/minitest/assertions.rb, line 463
def assert_silent
  assert_output "", "" do
    yield
  end
end
             
            Fails unless the block throws sym
 
               # File minitest-5.14.2/lib/minitest/assertions.rb, line 472
def assert_throws sym, msg = nil
  default = "Expected #{mu_pp(sym)} to have been thrown"
  caught = true
  catch(sym) do
    begin
      yield
    rescue ThreadError => e       # wtf?!? 1.8 + threads == suck
      default += ", not \:#{e.message[/uncaught throw \`(\w+?)\'/, 1]}"
    rescue ArgumentError => e     # 1.9 exception
      raise e unless e.message.include?("uncaught throw")
      default += ", not #{e.message.split(/ /).last}"
    rescue NameError => e         # 1.8 exception
      raise e unless e.name == sym
      default += ", not #{e.name.inspect}"
    end
    caught = false
  end
  assert caught, message(msg) { default }
rescue Assertion
  raise
rescue => e
  raise UnexpectedError, e
end
             
            Captures $stdout and $stderr into strings:
out, err = capture_io do puts "Some info" warn "You did a bad thing" end assert_match %r%info%, out assert_match %r%bad%, err
NOTE: For efficiency, this method uses StringIO and does not capture IO for subprocesses. Use capture_subprocess_io for that.
 
               # File minitest-5.14.2/lib/minitest/assertions.rb, line 512
def capture_io
  _synchronize do
    begin
      captured_stdout, captured_stderr = StringIO.new, StringIO.new
      orig_stdout, orig_stderr = $stdout, $stderr
      $stdout, $stderr         = captured_stdout, captured_stderr
      yield
      return captured_stdout.string, captured_stderr.string
    ensure
      $stdout = orig_stdout
      $stderr = orig_stderr
    end
  end
end
             
            Captures $stdout and $stderr into strings, using Tempfile to ensure that subprocess IO is captured as well.
out, err = capture_subprocess_io do system "echo Some info" system "echo You did a bad thing 1>&2" end assert_match %r%info%, out assert_match %r%bad%, err
NOTE: This method is approximately 10x slower than capture_io so only use it when you need to test the output of a subprocess.
 
               # File minitest-5.14.2/lib/minitest/assertions.rb, line 545
def capture_subprocess_io
  _synchronize do
    begin
      require "tempfile"
      captured_stdout, captured_stderr = Tempfile.new("out"), Tempfile.new("err")
      orig_stdout, orig_stderr = $stdout.dup, $stderr.dup
      $stdout.reopen captured_stdout
      $stderr.reopen captured_stderr
      yield
      $stdout.rewind
      $stderr.rewind
      return captured_stdout.read, captured_stderr.read
    ensure
      captured_stdout.unlink
      captured_stderr.unlink
      $stdout.reopen orig_stdout
      $stderr.reopen orig_stderr
      orig_stdout.close
      orig_stderr.close
      captured_stdout.close
      captured_stderr.close
    end
  end
end
             
            Returns a diff between exp and act. If there is
no known diff command or if it doesn't make sense to diff the output
(single line, short output), then it simply returns a basic comparison
between the two.
See things_to_diff for more info.
 
               # File minitest-5.14.2/lib/minitest/assertions.rb, line 58
def diff exp, act
  result = nil
  expect, butwas = things_to_diff(exp, act)
  return "Expected: #{mu_pp exp}\n  Actual: #{mu_pp act}" unless
    expect
  Tempfile.open("expect") do |a|
    a.puts expect
    a.flush
    Tempfile.open("butwas") do |b|
      b.puts butwas
      b.flush
      result = %x`#{Minitest::Assertions.diff} #{a.path} #{b.path}`
      result.sub!(/^\-\-\- .+/, "--- expected")
      result.sub!(/^\+\+\+ .+/, "+++ actual")
      if result.empty? then
        klass = exp.class
        result = [
                  "No visible difference in the #{klass}#inspect output.\n",
                  "You should look at the implementation of #== on ",
                  "#{klass} or its members.\n",
                  expect,
                 ].join
      end
    end
  end
  result
end
             
            Returns details for exception e
 
               # File minitest-5.14.2/lib/minitest/assertions.rb, line 579
def exception_details e, msg
  [
   "#{msg}",
   "Class: <#{e.class}>",
   "Message: <#{e.message.inspect}>",
   "---Backtrace---",
   "#{Minitest.filter_backtrace(e.backtrace).join("\n")}",
   "---------------",
  ].join "\n"
end
             
            Fails after a given date (in the local time zone). This allows you to put time-bombs in your tests if you need to keep something around until a later date lest you forget about it.
 
               # File minitest-5.14.2/lib/minitest/assertions.rb, line 595
def fail_after y,m,d,msg
  flunk msg if Time.now > Time.local(y, m, d)
end
             
            Fails with msg.
 
               # File minitest-5.14.2/lib/minitest/assertions.rb, line 602
def flunk msg = nil
  msg ||= "Epic Fail!"
  assert false, msg
end
             
            Returns a proc that will output msg along with the default
message.
 
               # File minitest-5.14.2/lib/minitest/assertions.rb, line 610
def message msg = nil, ending = nil, &default
  proc {
    msg = msg.call.chomp(".") if Proc === msg
    custom_message = "#{msg}.\n" unless msg.nil? or msg.to_s.empty?
    "#{custom_message}#{default.call}#{ending || "."}"
  }
end
             
            This returns a human-readable version of obj. By default
inspect is called. You can override this to use pretty_inspect if you want.
See Minitest::Test.make_my_diffs_pretty!
 
               # File minitest-5.14.2/lib/minitest/assertions.rb, line 128
def mu_pp obj
  s = obj.inspect
  if defined? Encoding then
    s = s.encode Encoding.default_external
    if String === obj && (obj.encoding != Encoding.default_external ||
                          !obj.valid_encoding?) then
      enc = "# encoding: #{obj.encoding}"
      val = "#    valid: #{obj.valid_encoding?}"
      s = "#{enc}\n#{val}\n#{s}"
    end
  end
  s
end
             
            This returns a diff-able more human-readable version of obj.
This differs from the regular #mu_pp because it expands escaped
newlines and makes hex-values (like object_ids) generic. This uses #mu_pp to do the first pass and
then cleans it up.
 
               # File minitest-5.14.2/lib/minitest/assertions.rb, line 151
def mu_pp_for_diff obj
  str = mu_pp obj
  # both '\n' & '\\n' (_after_ mu_pp (aka inspect))
  single = !!str.match(/(?<!\|^)\n/)
  double = !!str.match(/(?<=\|^)\n/)
  process =
    if single ^ double then
      if single then
        lambda { |s| s == "\\n"   ? "\n"    : s } # unescape
      else
        lambda { |s| s == "\\\\n" ? "\\n\n" : s } # unescape a bit, add nls
      end
    else
      :itself                                     # leave it alone
    end
  str.
    gsub(/\?\n/, &process).
    gsub(/:0x[a-fA-F0-9]{4,}/m, ":0xXXXXXX") # anonymize hex values
end
             
            used for counting assertions
 
               # File minitest-5.14.2/lib/minitest/assertions.rb, line 621
def pass _msg = nil
  assert true
end
             
            Fails if test is truthy.
 
               # File minitest-5.14.2/lib/minitest/assertions.rb, line 628
def refute test, msg = nil
  msg ||= message { "Expected #{mu_pp(test)} to not be truthy" }
  assert !test, msg
end
             
            Fails if obj is empty.
 
               # File minitest-5.14.2/lib/minitest/assertions.rb, line 636
def refute_empty obj, msg = nil
  msg = message(msg) { "Expected #{mu_pp(obj)} to not be empty" }
  assert_respond_to obj, :empty?
  refute obj.empty?, msg
end
             
            Fails if exp == act.
For floats use refute_in_delta.
 
               # File minitest-5.14.2/lib/minitest/assertions.rb, line 647
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
             
            For comparing Floats.  Fails if exp is within
delta of act.
refute_in_delta Math::PI, (22.0 / 7.0)
 
               # File minitest-5.14.2/lib/minitest/assertions.rb, line 659
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
             
            For comparing Floats.  Fails if exp and act have
a relative error less than epsilon.
 
               # File minitest-5.14.2/lib/minitest/assertions.rb, line 671
def refute_in_epsilon a, b, epsilon = 0.001, msg = nil
  refute_in_delta a, b, a * epsilon, msg
end
             
            Fails if collection includes obj.
 
               # File minitest-5.14.2/lib/minitest/assertions.rb, line 678
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
             
            Fails if obj is an instance of cls.
 
               # File minitest-5.14.2/lib/minitest/assertions.rb, line 689
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
             
            Fails if obj is a kind of cls.
 
               # File minitest-5.14.2/lib/minitest/assertions.rb, line 699
def refute_kind_of cls, obj, msg = nil
  msg = message(msg) { "Expected #{mu_pp(obj)} to not be a kind of #{cls}" }
  refute obj.kind_of?(cls), msg
end
             
            Fails if matcher =~ obj.
 
               # File minitest-5.14.2/lib/minitest/assertions.rb, line 707
def refute_match matcher, obj, msg = nil
  msg = message(msg) { "Expected #{mu_pp matcher} to not match #{mu_pp obj}" }
  assert_respond_to matcher, :"=~"
  matcher = Regexp.new Regexp.escape matcher if String === matcher
  refute matcher =~ obj, msg
end
             
            Fails if obj is nil.
 
               # File minitest-5.14.2/lib/minitest/assertions.rb, line 717
def refute_nil obj, msg = nil
  msg = message(msg) { "Expected #{mu_pp(obj)} to not be nil" }
  refute obj.nil?, msg
end
             
            Fails if o1 is not op o2. Eg:
refute_operator 1, :>, 2 #=> pass refute_operator 1, :<, 2 #=> fail
 
               # File minitest-5.14.2/lib/minitest/assertions.rb, line 728
def refute_operator o1, op, o2 = UNDEFINED, msg = nil
  return refute_predicate o1, op, msg if UNDEFINED == o2
  msg = message(msg) { "Expected #{mu_pp(o1)} to not be #{op} #{mu_pp(o2)}" }
  refute o1.__send__(op, o2), msg
end
             
            Fails if path exists.
 
               # File minitest-5.14.2/lib/minitest/assertions.rb, line 737
def refute_path_exists path, msg = nil
  msg = message(msg) { "Expected path '#{path}' to not exist" }
  refute File.exist?(path), msg
end
             
            For testing with predicates.
refute_predicate str, :empty?
This is really meant for specs and is front-ended by #refute_operator:
str.wont_be :empty?
 
               # File minitest-5.14.2/lib/minitest/assertions.rb, line 751
def refute_predicate o1, op, msg = nil
  msg = message(msg) { "Expected #{mu_pp(o1)} to not be #{op}" }
  refute o1.__send__(op), msg
end
             
            Fails if obj responds to the message meth.
 
               # File minitest-5.14.2/lib/minitest/assertions.rb, line 759
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
             
            Fails if exp is the same (by object identity) as
act.
 
               # File minitest-5.14.2/lib/minitest/assertions.rb, line 768
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
             
            Skips the current run. If run in verbose-mode, the skipped run gets listed at the end of the run but doesn't cause a failure exit code.
 
               # File minitest-5.14.2/lib/minitest/assertions.rb, line 781
def skip msg = nil, bt = caller
  msg ||= "Skipped, no message given"
  @skip = true
  raise Minitest::Skip, msg, bt
end
             
            Skips the current run until a given date (in the local time zone). This allows you to put some fixes on hold until a later date, but still holds you accountable and prevents you from forgetting it.
 
               # File minitest-5.14.2/lib/minitest/assertions.rb, line 793
def skip_until y,m,d,msg
  skip msg if Time.now < Time.local(y, m, d)
  where = caller.first.split(/:/, 3).first(2).join ":"
  warn "Stale skip_until %p at %s" % [msg, where]
end
             
            Was this testcase skipped? Meant for teardown.
 
               # File minitest-5.14.2/lib/minitest/assertions.rb, line 802
def skipped?
  defined?(@skip) and @skip
end
             
            Returns things to diff [expect, butwas], or [nil, nil] if nothing to diff.
Criterion:
Strings include newlines or escaped newlines, but not both.
or: String lengths are > 30 characters.
or: Strings are equal to each other (but maybe different encodings?).
and: we found a diff executable.
 
               # File minitest-5.14.2/lib/minitest/assertions.rb, line 103
def things_to_diff exp, act
  expect = mu_pp_for_diff exp
  butwas = mu_pp_for_diff act
  e1, e2 = expect.include?("\n"), expect.include?("\\n")
  b1, b2 = butwas.include?("\n"), butwas.include?("\\n")
  need_to_diff =
    (e1 ^ e2                  ||
     b1 ^ b2                  ||
     expect.size > 30         ||
     butwas.size > 30         ||
     expect == butwas)        &&
    Minitest::Assertions.diff
  need_to_diff && [expect, butwas]
end