module Minitest::Assertions
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.
Public Class Methods
# File lib/minitest/assertions.rb, line 29
def self.diff
@diff = if (RbConfig::CONFIG["host_os"] =~ /mswin|mingw/ &&
system("diff.exe", __FILE__, __FILE__)) then
"diff.exe -u"
elsif Minitest::Test.maglev? then
"diff -u"
elsif system("gdiff", __FILE__, __FILE__)
"gdiff -u" # solaris and kin suck
elsif system("diff", __FILE__, __FILE__)
"diff -u"
else
nil
end unless defined? @diff
@diff
end Returns the diff command to use in diff. Tries to intelligently figure out what diff to use.
# File lib/minitest/assertions.rb, line 49 def self.diff= o @diff = o end
Set the diff command to use in diff.
Public Instance Methods
# File lib/minitest/assertions.rb, line 134
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 test is truthy.
# File lib/minitest/assertions.rb, line 151
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 obj is empty.
# File lib/minitest/assertions.rb, line 172
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 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 lib/minitest/assertions.rb, line 196
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 are within delta of each other.
assert_in_delta Math::PI, (22.0 / 7.0), 0.01
# File lib/minitest/assertions.rb, line 208 def assert_in_epsilon exp, act, epsilon = 0.001, msg = nil assert_in_delta exp, act, [exp.abs, act.abs].min * epsilon, msg end
For comparing Floats. Fails unless exp and act have a relative error less than epsilon.
# File lib/minitest/assertions.rb, line 215
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 collection includes obj.
# File lib/minitest/assertions.rb, line 226
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 an instance of cls.
# File lib/minitest/assertions.rb, line 237
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 obj is a kind of cls.
# File lib/minitest/assertions.rb, line 247
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 Fails unless matcher =~ obj.
# File lib/minitest/mock.rb, line 184 def assert_mock mock assert mock.verify end
Assert that the mock verifies correctly.
# File lib/minitest/assertions.rb, line 257
def assert_nil obj, msg = nil
msg = message(msg) { "Expected #{mu_pp(obj)} to be nil" }
assert obj.nil?, msg
end Fails unless obj is nil
# File lib/minitest/assertions.rb, line 267
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 For testing with binary operators. Eg:
assert_operator 5, :<=, 4
# File lib/minitest/assertions.rb, line 285
def assert_output stdout = nil, stderr = nil
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)
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 lib/minitest/assertions.rb, line 308
def assert_predicate o1, op, msg = nil
msg = message(msg) { "Expected #{mu_pp(o1)} to be #{op}" }
assert o1.__send__(op), 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 lib/minitest/assertions.rb, line 321
def assert_raises *exp
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::Skip, Minitest::Assertion
# 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 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.
# File lib/minitest/assertions.rb, line 349
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 obj responds to meth.
# File lib/minitest/assertions.rb, line 359
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 Fails unless exp and act are equal?
# File lib/minitest/assertions.rb, line 372
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 send_ary is a receiver, message and arguments.
Fails unless the call returns a true value
# File lib/minitest/assertions.rb, line 388
def assert_silent
assert_output "", "" do
yield
end
end Fails if the block outputs anything to stderr or stdout.
See also: assert_output
# File lib/minitest/assertions.rb, line 397
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 }
end Fails unless the block throws sym
# File lib/minitest/assertions.rb, line 433
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:
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 lib/minitest/assertions.rb, line 466
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
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 lib/minitest/assertions.rb, line 59
def diff exp, act
expect = mu_pp_for_diff exp
butwas = mu_pp_for_diff act
result = nil
need_to_diff =
(expect.include?("\n") ||
butwas.include?("\n") ||
expect.size > 30 ||
butwas.size > 30 ||
expect == butwas) &&
Minitest::Assertions.diff
return "Expected: #{mu_pp exp}\n Actual: #{mu_pp act}" unless
need_to_diff
Tempfile.open("expect") do |a|
a.puts expect
a.flush
Tempfile.open("butwas") do |b|
b.puts butwas
b.flush
result = `#{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 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.
# File lib/minitest/assertions.rb, line 495
def exception_details e, msg
[
"#{msg}",
"Class: <#{e.class}>",
"Message: <#{e.message.inspect}>",
"---Backtrace---",
"#{Minitest.filter_backtrace(e.backtrace).join("\n")}",
"---------------",
].join "\n"
end Returns details for exception e
# File lib/minitest/assertions.rb, line 509 def flunk msg = nil msg ||= "Epic Fail!" assert false, msg end
Fails with msg
# File lib/minitest/assertions.rb, line 517
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 Returns a proc that will output msg along with the default message.
# File lib/minitest/assertions.rb, line 107
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 then
s = "# encoding: #{obj.encoding}\n#{s}"
end
end
s
end This returns a human-readable version of obj. By default inspect is called. You can override this to use pretty_print if you want.
# File lib/minitest/assertions.rb, line 127
def mu_pp_for_diff obj
mu_pp(obj).gsub(/\\n/, "\n").gsub(/:0x[a-fA-F0-9]{4,}/m, ":0xXXXXXX")
end This returns a diff-able human-readable version of obj. This differs from the regular #mu_pp because it expands escaped newlines and makes hex-values generic (like object_ids). This uses #mu_pp to do the first pass and then cleans it up.
# File lib/minitest/assertions.rb, line 528 def pass _msg = nil assert true end
used for counting assertions
# File lib/minitest/assertions.rb, line 535
def refute test, msg = nil
msg ||= message { "Expected #{mu_pp(test)} to not be truthy" }
not assert !test, msg
end Fails if test is truthy.
# File lib/minitest/assertions.rb, line 543
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 obj is empty.
# File lib/minitest/assertions.rb, line 554
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 Fails if exp == act.
For floats use refute_in_delta.
# File lib/minitest/assertions.rb, line 566
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 is within delta of act.
refute_in_delta Math::PI, (22.0 / 7.0)
# File lib/minitest/assertions.rb, line 578 def refute_in_epsilon a, b, epsilon = 0.001, msg = nil refute_in_delta a, b, a * epsilon, msg end
For comparing Floats. Fails if exp and act have a relative error less than epsilon.
# File lib/minitest/assertions.rb, line 585
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 collection includes obj.
# File lib/minitest/assertions.rb, line 596
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 an instance of cls.
# File lib/minitest/assertions.rb, line 606
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 obj is a kind of cls.
# File lib/minitest/assertions.rb, line 614
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 matcher =~ obj.
# File lib/minitest/assertions.rb, line 624
def refute_nil obj, msg = nil
msg = message(msg) { "Expected #{mu_pp(obj)} to not be nil" }
refute obj.nil?, msg
end Fails if obj is nil.
# File lib/minitest/assertions.rb, line 635
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 o1 is not op o2. Eg:
refute_operator 1, :>, 2 #=> pass refute_operator 1, :<, 2 #=> fail
# File lib/minitest/assertions.rb, line 650
def refute_predicate o1, op, msg = nil
msg = message(msg) { "Expected #{mu_pp(o1)} to not be #{op}" }
refute o1.__send__(op), 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 lib/minitest/assertions.rb, line 658
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 obj responds to the message meth.
# File lib/minitest/assertions.rb, line 667
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 Fails if exp is the same (by object identity) as act.
# File lib/minitest/assertions.rb, line 680 def skip msg = nil, bt = caller msg ||= "Skipped, no message given" @skip = true raise Minitest::Skip, msg, bt 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 lib/minitest/assertions.rb, line 689 def skipped? defined?(@skip) and @skip end
Was this testcase skipped? Meant for teardown.
© Ryan Davis, seattle.rb
Licensed under the MIT License.