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MiniTest Assertions. All assertion methods accept a
msg which is printed if the assertion fails.
Returns the diff command to use in diff. Tries to intelligently figure out what diff to use.
# File minitest/unit.rb, line 75
def self.diff
@diff = if WINDOZE
"diff.exe -u"
else
if system("gdiff", __FILE__, __FILE__)
"gdiff -u" # solaris and kin suck
elsif system("diff", __FILE__, __FILE__)
"diff -u"
else
nil
end
end unless defined? @diff
@diff
end
Set the diff command to use in diff.
# File minitest/unit.rb, line 94
def self.diff= o
@diff = o
end
Fails unless test is a true value.
# File minitest/unit.rb, line 180
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
Fails unless the block returns a true value.
# File minitest/unit.rb, line 193
def assert_block msg = nil
msg = message(msg) { "Expected block to return true value" }
assert yield, msg
end
Fails unless obj is empty.
# File minitest/unit.rb, line 201
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 floats use assert_in_delta.
See also: ::diff
# File minitest/unit.rb, line 219
def assert_equal exp, act, msg = nil
msg = message(msg, "") { diff exp, act }
assert(exp == act, 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 minitest/unit.rb, line 230
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/unit.rb, line 240
def assert_in_epsilon a, b, epsilon = 0.001, msg = nil
assert_in_delta a, b, [a, b].min * epsilon, msg
end
Fails unless collection includes obj.
# File minitest/unit.rb, line 247
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 instace of cls.
# File minitest/unit.rb, line 258
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/unit.rb, line 269
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
Fails unless exp is =~ act.
# File minitest/unit.rb, line 279
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.new Regexp.escape exp if String === exp and String === act
assert exp =~ act, msg
end
Fails unless obj is nil
# File minitest/unit.rb, line 289
def assert_nil obj, msg = nil
msg = message(msg) { "Expected #{mu_pp(obj)} to be nil" }
assert obj.nil?, msg
end
For testing equality operators and so-forth.
assert_operator 5, :<=, 4
# File minitest/unit.rb, line 299
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
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.
See also: assert_silent
# File minitest/unit.rb, line 311
def assert_output stdout = nil, stderr = nil
out, err = capture_io do
yield
end
x = assert_equal stdout, out, "In stdout" if stdout
y = assert_equal stderr, err, "In stderr" if stderr
(!stdout || x) && (!stderr || y)
end
Fails unless the block raises one of exp
# File minitest/unit.rb, line 325
def assert_raises *exp
msg = "#{exp.pop}\n" if String === exp.last
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
Fails unless obj responds to meth.
# File minitest/unit.rb, line 357
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/unit.rb, line 367
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 TODO: I should prolly remove this from specs
# File minitest/unit.rb, line 381
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
Fails if the block outputs anything to stderr or stdout.
See also: assert_output
# File minitest/unit.rb, line 393
def assert_silent
assert_output "", "" do
yield
end
end
Fails unless the block throws sym
# File minitest/unit.rb, line 402
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
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 428
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
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 minitest/unit.rb, line 104
def diff exp, act
require "tempfile"
expect = mu_pp_for_diff exp
butwas = mu_pp_for_diff act
result = nil
need_to_diff =
MiniTest::Assertions.diff &&
(expect.include?("\n") ||
butwas.include?("\n") ||
expect.size > 30 ||
butwas.size > 30 ||
expect == butwas)
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 = %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.",
"You should look at your implementation of #{klass}#==.",
expect
].join "\n"
end
end
end
result
end
Returns details for exception e
# File minitest/unit.rb, line 446
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 with msg
# File minitest/unit.rb, line 460
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/unit.rb, line 468
def message msg = nil, ending = ".", &default
proc {
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_print if you want.
# File minitest/unit.rb, line 153
def mu_pp obj
s = obj.inspect
s = s.encode Encoding.default_external if defined? Encoding
s
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 minitest/unit.rb, line 165
def mu_pp_for_diff obj # TODO: possibly rename
mu_pp(obj).gsub(/\n/, "\n").gsub(/0x[a-f0-9]+/m, '0xXXXXXX')
end
used for counting assertions
# File minitest/unit.rb, line 478
def pass msg = nil
assert true
end
Fails if test is a true value
# File minitest/unit.rb, line 485
def refute test, msg = nil
msg ||= "Failed refutation, no message given"
not assert(! test, msg)
end
Fails if obj is empty.
# File minitest/unit.rb, line 493
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/unit.rb, line 504
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/unit.rb, line 516
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/unit.rb, line 528
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/unit.rb, line 535
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/unit.rb, line 546
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/unit.rb, line 556
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
Fails if exp =~ act
# File minitest/unit.rb, line 564
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
Fails if obj is nil.
# File minitest/unit.rb, line 574
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/unit.rb, line 585
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
Fails if obj responds to the message meth.
# File minitest/unit.rb, line 595
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/unit.rb, line 604
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
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