1Test::More(3) User Contributed Perl Documentation Test::More(3)
2
3
4
6 Test::More - yet another framework for writing test scripts
7
9 use Test::More tests => 23;
10 # or
11 use Test::More skip_all => $reason;
12 # or
13 use Test::More; # see done_testing()
14
15 BEGIN { use_ok( 'Some::Module' ); }
16 require_ok( 'Some::Module' );
17
18 # Various ways to say "ok"
19 ok($got eq $expected, $test_name);
20
21 is ($got, $expected, $test_name);
22 isnt($got, $expected, $test_name);
23
24 # Rather than print STDERR "# here's what went wrong\n"
25 diag("here's what went wrong");
26
27 like ($got, qr/expected/, $test_name);
28 unlike($got, qr/expected/, $test_name);
29
30 cmp_ok($got, '==', $expected, $test_name);
31
32 is_deeply($got_complex_structure, $expected_complex_structure, $test_name);
33
34 SKIP: {
35 skip $why, $how_many unless $have_some_feature;
36
37 ok( foo(), $test_name );
38 is( foo(42), 23, $test_name );
39 };
40
41 TODO: {
42 local $TODO = $why;
43
44 ok( foo(), $test_name );
45 is( foo(42), 23, $test_name );
46 };
47
48 can_ok($module, @methods);
49 isa_ok($object, $class);
50
51 pass($test_name);
52 fail($test_name);
53
54 BAIL_OUT($why);
55
56 # UNIMPLEMENTED!!!
57 my @status = Test::More::status;
58
60 STOP! If you're just getting started writing tests, have a look at
61 Test::Simple first. This is a drop in replacement for Test::Simple
62 which you can switch to once you get the hang of basic testing.
63
64 The purpose of this module is to provide a wide range of testing
65 utilities. Various ways to say "ok" with better diagnostics,
66 facilities to skip tests, test future features and compare complicated
67 data structures. While you can do almost anything with a simple "ok()"
68 function, it doesn't provide good diagnostic output.
69
70 I love it when a plan comes together
71 Before anything else, you need a testing plan. This basically declares
72 how many tests your script is going to run to protect against premature
73 failure.
74
75 The preferred way to do this is to declare a plan when you "use
76 Test::More".
77
78 use Test::More tests => 23;
79
80 There are cases when you will not know beforehand how many tests your
81 script is going to run. In this case, you can declare your tests at
82 the end.
83
84 use Test::More;
85
86 ... run your tests ...
87
88 done_testing( $number_of_tests_run );
89
90 Sometimes you really don't know how many tests were run, or it's too
91 difficult to calculate. In which case you can leave off
92 $number_of_tests_run.
93
94 In some cases, you'll want to completely skip an entire testing script.
95
96 use Test::More skip_all => $skip_reason;
97
98 Your script will declare a skip with the reason why you skipped and
99 exit immediately with a zero (success). See Test::Harness for details.
100
101 If you want to control what functions Test::More will export, you have
102 to use the 'import' option. For example, to import everything but
103 'fail', you'd do:
104
105 use Test::More tests => 23, import => ['!fail'];
106
107 Alternatively, you can use the plan() function. Useful for when you
108 have to calculate the number of tests.
109
110 use Test::More;
111 plan tests => keys %Stuff * 3;
112
113 or for deciding between running the tests at all:
114
115 use Test::More;
116 if( $^O eq 'MacOS' ) {
117 plan skip_all => 'Test irrelevant on MacOS';
118 }
119 else {
120 plan tests => 42;
121 }
122
123 done_testing
124 done_testing();
125 done_testing($number_of_tests);
126
127 If you don't know how many tests you're going to run, you can issue
128 the plan when you're done running tests.
129
130 $number_of_tests is the same as plan(), it's the number of tests
131 you expected to run. You can omit this, in which case the number
132 of tests you ran doesn't matter, just the fact that your tests ran
133 to conclusion.
134
135 This is safer than and replaces the "no_plan" plan.
136
137 Test names
138 By convention, each test is assigned a number in order. This is
139 largely done automatically for you. However, it's often very useful to
140 assign a name to each test. Which would you rather see:
141
142 ok 4
143 not ok 5
144 ok 6
145
146 or
147
148 ok 4 - basic multi-variable
149 not ok 5 - simple exponential
150 ok 6 - force == mass * acceleration
151
152 The later gives you some idea of what failed. It also makes it easier
153 to find the test in your script, simply search for "simple
154 exponential".
155
156 All test functions take a name argument. It's optional, but highly
157 suggested that you use it.
158
159 I'm ok, you're not ok.
160 The basic purpose of this module is to print out either "ok #" or "not
161 ok #" depending on if a given test succeeded or failed. Everything
162 else is just gravy.
163
164 All of the following print "ok" or "not ok" depending on if the test
165 succeeded or failed. They all also return true or false, respectively.
166
167 ok
168 ok($got eq $expected, $test_name);
169
170 This simply evaluates any expression ("$got eq $expected" is just a
171 simple example) and uses that to determine if the test succeeded or
172 failed. A true expression passes, a false one fails. Very simple.
173
174 For example:
175
176 ok( $exp{9} == 81, 'simple exponential' );
177 ok( Film->can('db_Main'), 'set_db()' );
178 ok( $p->tests == 4, 'saw tests' );
179 ok( !grep !defined $_, @items, 'items populated' );
180
181 (Mnemonic: "This is ok.")
182
183 $test_name is a very short description of the test that will be
184 printed out. It makes it very easy to find a test in your script
185 when it fails and gives others an idea of your intentions.
186 $test_name is optional, but we very strongly encourage its use.
187
188 Should an ok() fail, it will produce some diagnostics:
189
190 not ok 18 - sufficient mucus
191 # Failed test 'sufficient mucus'
192 # in foo.t at line 42.
193
194 This is the same as Test::Simple's ok() routine.
195
196 is
197 isnt
198 is ( $got, $expected, $test_name );
199 isnt( $got, $expected, $test_name );
200
201 Similar to ok(), is() and isnt() compare their two arguments with
202 "eq" and "ne" respectively and use the result of that to determine
203 if the test succeeded or failed. So these:
204
205 # Is the ultimate answer 42?
206 is( ultimate_answer(), 42, "Meaning of Life" );
207
208 # $foo isn't empty
209 isnt( $foo, '', "Got some foo" );
210
211 are similar to these:
212
213 ok( ultimate_answer() eq 42, "Meaning of Life" );
214 ok( $foo ne '', "Got some foo" );
215
216 "undef" will only ever match "undef". So you can test a value
217 agains "undef" like this:
218
219 is($not_defined, undef, "undefined as expected");
220
221 (Mnemonic: "This is that." "This isn't that.")
222
223 So why use these? They produce better diagnostics on failure.
224 ok() cannot know what you are testing for (beyond the name), but
225 is() and isnt() know what the test was and why it failed. For
226 example this test:
227
228 my $foo = 'waffle'; my $bar = 'yarblokos';
229 is( $foo, $bar, 'Is foo the same as bar?' );
230
231 Will produce something like this:
232
233 not ok 17 - Is foo the same as bar?
234 # Failed test 'Is foo the same as bar?'
235 # in foo.t at line 139.
236 # got: 'waffle'
237 # expected: 'yarblokos'
238
239 So you can figure out what went wrong without rerunning the test.
240
241 You are encouraged to use is() and isnt() over ok() where possible,
242 however do not be tempted to use them to find out if something is
243 true or false!
244
245 # XXX BAD!
246 is( exists $brooklyn{tree}, 1, 'A tree grows in Brooklyn' );
247
248 This does not check if "exists $brooklyn{tree}" is true, it checks
249 if it returns 1. Very different. Similar caveats exist for false
250 and 0. In these cases, use ok().
251
252 ok( exists $brooklyn{tree}, 'A tree grows in Brooklyn' );
253
254 A simple call to isnt() usually does not provide a strong test but
255 there are cases when you cannot say much more about a value than
256 that it is different from some other value:
257
258 new_ok $obj, "Foo";
259
260 my $clone = $obj->clone;
261 isa_ok $obj, "Foo", "Foo->clone";
262
263 isnt $obj, $clone, "clone() produces a different object";
264
265 For those grammatical pedants out there, there's an "isn't()"
266 function which is an alias of isnt().
267
268 like
269 like( $got, qr/expected/, $test_name );
270
271 Similar to ok(), like() matches $got against the regex
272 "qr/expected/".
273
274 So this:
275
276 like($got, qr/expected/, 'this is like that');
277
278 is similar to:
279
280 ok( $got =~ /expected/, 'this is like that');
281
282 (Mnemonic "This is like that".)
283
284 The second argument is a regular expression. It may be given as a
285 regex reference (i.e. "qr//") or (for better compatibility with
286 older perls) as a string that looks like a regex (alternative
287 delimiters are currently not supported):
288
289 like( $got, '/expected/', 'this is like that' );
290
291 Regex options may be placed on the end ('/expected/i').
292
293 Its advantages over ok() are similar to that of is() and isnt().
294 Better diagnostics on failure.
295
296 unlike
297 unlike( $got, qr/expected/, $test_name );
298
299 Works exactly as like(), only it checks if $got does not match the
300 given pattern.
301
302 cmp_ok
303 cmp_ok( $got, $op, $expected, $test_name );
304
305 Halfway between ok() and is() lies cmp_ok(). This allows you to
306 compare two arguments using any binary perl operator.
307
308 # ok( $got eq $expected );
309 cmp_ok( $got, 'eq', $expected, 'this eq that' );
310
311 # ok( $got == $expected );
312 cmp_ok( $got, '==', $expected, 'this == that' );
313
314 # ok( $got && $expected );
315 cmp_ok( $got, '&&', $expected, 'this && that' );
316 ...etc...
317
318 Its advantage over ok() is when the test fails you'll know what
319 $got and $expected were:
320
321 not ok 1
322 # Failed test in foo.t at line 12.
323 # '23'
324 # &&
325 # undef
326
327 It's also useful in those cases where you are comparing numbers and
328 is()'s use of "eq" will interfere:
329
330 cmp_ok( $big_hairy_number, '==', $another_big_hairy_number );
331
332 It's especially useful when comparing greater-than or smaller-than
333 relation between values:
334
335 cmp_ok( $some_value, '<=', $upper_limit );
336
337 can_ok
338 can_ok($module, @methods);
339 can_ok($object, @methods);
340
341 Checks to make sure the $module or $object can do these @methods
342 (works with functions, too).
343
344 can_ok('Foo', qw(this that whatever));
345
346 is almost exactly like saying:
347
348 ok( Foo->can('this') &&
349 Foo->can('that') &&
350 Foo->can('whatever')
351 );
352
353 only without all the typing and with a better interface. Handy for
354 quickly testing an interface.
355
356 No matter how many @methods you check, a single can_ok() call
357 counts as one test. If you desire otherwise, use:
358
359 foreach my $meth (@methods) {
360 can_ok('Foo', $meth);
361 }
362
363 isa_ok
364 isa_ok($object, $class, $object_name);
365 isa_ok($subclass, $class, $object_name);
366 isa_ok($ref, $type, $ref_name);
367
368 Checks to see if the given "$object->isa($class)". Also checks to
369 make sure the object was defined in the first place. Handy for
370 this sort of thing:
371
372 my $obj = Some::Module->new;
373 isa_ok( $obj, 'Some::Module' );
374
375 where you'd otherwise have to write
376
377 my $obj = Some::Module->new;
378 ok( defined $obj && $obj->isa('Some::Module') );
379
380 to safeguard against your test script blowing up.
381
382 You can also test a class, to make sure that it has the right
383 ancestor:
384
385 isa_ok( 'Vole', 'Rodent' );
386
387 It works on references, too:
388
389 isa_ok( $array_ref, 'ARRAY' );
390
391 The diagnostics of this test normally just refer to 'the object'.
392 If you'd like them to be more specific, you can supply an
393 $object_name (for example 'Test customer').
394
395 new_ok
396 my $obj = new_ok( $class );
397 my $obj = new_ok( $class => \@args );
398 my $obj = new_ok( $class => \@args, $object_name );
399
400 A convenience function which combines creating an object and
401 calling isa_ok() on that object.
402
403 It is basically equivalent to:
404
405 my $obj = $class->new(@args);
406 isa_ok $obj, $class, $object_name;
407
408 If @args is not given, an empty list will be used.
409
410 This function only works on new() and it assumes new() will return
411 just a single object which isa $class.
412
413 subtest
414 subtest $name => \&code;
415
416 subtest() runs the &code as its own little test with its own plan
417 and its own result. The main test counts this as a single test
418 using the result of the whole subtest to determine if its ok or not
419 ok.
420
421 For example...
422
423 use Test::More tests => 3;
424
425 pass("First test");
426
427 subtest 'An example subtest' => sub {
428 plan tests => 2;
429
430 pass("This is a subtest");
431 pass("So is this");
432 };
433
434 pass("Third test");
435
436 This would produce.
437
438 1..3
439 ok 1 - First test
440 1..2
441 ok 1 - This is a subtest
442 ok 2 - So is this
443 ok 2 - An example subtest
444 ok 3 - Third test
445
446 A subtest may call "skip_all". No tests will be run, but the
447 subtest is considered a skip.
448
449 subtest 'skippy' => sub {
450 plan skip_all => 'cuz I said so';
451 pass('this test will never be run');
452 };
453
454 Returns true if the subtest passed, false otherwise.
455
456 Due to how subtests work, you may omit a plan if you desire. This
457 adds an implicit "done_testing()" to the end of your subtest. The
458 following two subtests are equivalent:
459
460 subtest 'subtest with implicit done_testing()', sub {
461 ok 1, 'subtests with an implicit done testing should work';
462 ok 1, '... and support more than one test';
463 ok 1, '... no matter how many tests are run';
464 };
465
466 subtest 'subtest with explicit done_testing()', sub {
467 ok 1, 'subtests with an explicit done testing should work';
468 ok 1, '... and support more than one test';
469 ok 1, '... no matter how many tests are run';
470 done_testing();
471 };
472
473 pass
474 fail
475 pass($test_name);
476 fail($test_name);
477
478 Sometimes you just want to say that the tests have passed. Usually
479 the case is you've got some complicated condition that is difficult
480 to wedge into an ok(). In this case, you can simply use pass() (to
481 declare the test ok) or fail (for not ok). They are synonyms for
482 ok(1) and ok(0).
483
484 Use these very, very, very sparingly.
485
486 Module tests
487 You usually want to test if the module you're testing loads ok, rather
488 than just vomiting if its load fails. For such purposes we have
489 "use_ok" and "require_ok".
490
491 use_ok
492 BEGIN { use_ok($module); }
493 BEGIN { use_ok($module, @imports); }
494
495 These simply use the given $module and test to make sure the load
496 happened ok. It's recommended that you run use_ok() inside a BEGIN
497 block so its functions are exported at compile-time and prototypes
498 are properly honored.
499
500 If @imports are given, they are passed through to the use. So
501 this:
502
503 BEGIN { use_ok('Some::Module', qw(foo bar)) }
504
505 is like doing this:
506
507 use Some::Module qw(foo bar);
508
509 Version numbers can be checked like so:
510
511 # Just like "use Some::Module 1.02"
512 BEGIN { use_ok('Some::Module', 1.02) }
513
514 Don't try to do this:
515
516 BEGIN {
517 use_ok('Some::Module');
518
519 ...some code that depends on the use...
520 ...happening at compile time...
521 }
522
523 because the notion of "compile-time" is relative. Instead, you
524 want:
525
526 BEGIN { use_ok('Some::Module') }
527 BEGIN { ...some code that depends on the use... }
528
529 If you want the equivalent of "use Foo ()", use a module but not
530 import anything, use "require_ok".
531
532 BEGIN { require_ok "Foo" }
533
534 require_ok
535 require_ok($module);
536 require_ok($file);
537
538 Like use_ok(), except it requires the $module or $file.
539
540 Complex data structures
541 Not everything is a simple eq check or regex. There are times you need
542 to see if two data structures are equivalent. For these instances
543 Test::More provides a handful of useful functions.
544
545 NOTE I'm not quite sure what will happen with filehandles.
546
547 is_deeply
548 is_deeply( $got, $expected, $test_name );
549
550 Similar to is(), except that if $got and $expected are references,
551 it does a deep comparison walking each data structure to see if
552 they are equivalent. If the two structures are different, it will
553 display the place where they start differing.
554
555 is_deeply() compares the dereferenced values of references, the
556 references themselves (except for their type) are ignored. This
557 means aspects such as blessing and ties are not considered
558 "different".
559
560 is_deeply() currently has very limited handling of function
561 reference and globs. It merely checks if they have the same
562 referent. This may improve in the future.
563
564 Test::Differences and Test::Deep provide more in-depth
565 functionality along these lines.
566
567 Diagnostics
568 If you pick the right test function, you'll usually get a good idea of
569 what went wrong when it failed. But sometimes it doesn't work out that
570 way. So here we have ways for you to write your own diagnostic
571 messages which are safer than just "print STDERR".
572
573 diag
574 diag(@diagnostic_message);
575
576 Prints a diagnostic message which is guaranteed not to interfere
577 with test output. Like "print" @diagnostic_message is simply
578 concatenated together.
579
580 Returns false, so as to preserve failure.
581
582 Handy for this sort of thing:
583
584 ok( grep(/foo/, @users), "There's a foo user" ) or
585 diag("Since there's no foo, check that /etc/bar is set up right");
586
587 which would produce:
588
589 not ok 42 - There's a foo user
590 # Failed test 'There's a foo user'
591 # in foo.t at line 52.
592 # Since there's no foo, check that /etc/bar is set up right.
593
594 You might remember "ok() or diag()" with the mnemonic "open() or
595 die()".
596
597 NOTE The exact formatting of the diagnostic output is still
598 changing, but it is guaranteed that whatever you throw at it it
599 won't interfere with the test.
600
601 note
602 note(@diagnostic_message);
603
604 Like diag(), except the message will not be seen when the test is
605 run in a harness. It will only be visible in the verbose TAP
606 stream.
607
608 Handy for putting in notes which might be useful for debugging, but
609 don't indicate a problem.
610
611 note("Tempfile is $tempfile");
612
613 explain
614 my @dump = explain @diagnostic_message;
615
616 Will dump the contents of any references in a human readable
617 format. Usually you want to pass this into "note" or "diag".
618
619 Handy for things like...
620
621 is_deeply($have, $want) || diag explain $have;
622
623 or
624
625 note explain \%args;
626 Some::Class->method(%args);
627
628 Conditional tests
629 Sometimes running a test under certain conditions will cause the test
630 script to die. A certain function or method isn't implemented (such as
631 fork() on MacOS), some resource isn't available (like a net connection)
632 or a module isn't available. In these cases it's necessary to skip
633 tests, or declare that they are supposed to fail but will work in the
634 future (a todo test).
635
636 For more details on the mechanics of skip and todo tests see
637 Test::Harness.
638
639 The way Test::More handles this is with a named block. Basically, a
640 block of tests which can be skipped over or made todo. It's best if I
641 just show you...
642
643 SKIP: BLOCK
644 SKIP: {
645 skip $why, $how_many if $condition;
646
647 ...normal testing code goes here...
648 }
649
650 This declares a block of tests that might be skipped, $how_many
651 tests there are, $why and under what $condition to skip them. An
652 example is the easiest way to illustrate:
653
654 SKIP: {
655 eval { require HTML::Lint };
656
657 skip "HTML::Lint not installed", 2 if $@;
658
659 my $lint = new HTML::Lint;
660 isa_ok( $lint, "HTML::Lint" );
661
662 $lint->parse( $html );
663 is( $lint->errors, 0, "No errors found in HTML" );
664 }
665
666 If the user does not have HTML::Lint installed, the whole block of
667 code won't be run at all. Test::More will output special ok's
668 which Test::Harness interprets as skipped, but passing, tests.
669
670 It's important that $how_many accurately reflects the number of
671 tests in the SKIP block so the # of tests run will match up with
672 your plan. If your plan is "no_plan" $how_many is optional and
673 will default to 1.
674
675 It's perfectly safe to nest SKIP blocks. Each SKIP block must have
676 the label "SKIP", or Test::More can't work its magic.
677
678 You don't skip tests which are failing because there's a bug in
679 your program, or for which you don't yet have code written. For
680 that you use TODO. Read on.
681
682 TODO: BLOCK
683 TODO: {
684 local $TODO = $why if $condition;
685
686 ...normal testing code goes here...
687 }
688
689 Declares a block of tests you expect to fail and $why. Perhaps
690 it's because you haven't fixed a bug or haven't finished a new
691 feature:
692
693 TODO: {
694 local $TODO = "URI::Geller not finished";
695
696 my $card = "Eight of clubs";
697 is( URI::Geller->your_card, $card, 'Is THIS your card?' );
698
699 my $spoon;
700 URI::Geller->bend_spoon;
701 is( $spoon, 'bent', "Spoon bending, that's original" );
702 }
703
704 With a todo block, the tests inside are expected to fail.
705 Test::More will run the tests normally, but print out special flags
706 indicating they are "todo". Test::Harness will interpret failures
707 as being ok. Should anything succeed, it will report it as an
708 unexpected success. You then know the thing you had todo is done
709 and can remove the TODO flag.
710
711 The nice part about todo tests, as opposed to simply commenting out
712 a block of tests, is it's like having a programmatic todo list.
713 You know how much work is left to be done, you're aware of what
714 bugs there are, and you'll know immediately when they're fixed.
715
716 Once a todo test starts succeeding, simply move it outside the
717 block. When the block is empty, delete it.
718
719 todo_skip
720 TODO: {
721 todo_skip $why, $how_many if $condition;
722
723 ...normal testing code...
724 }
725
726 With todo tests, it's best to have the tests actually run. That
727 way you'll know when they start passing. Sometimes this isn't
728 possible. Often a failing test will cause the whole program to die
729 or hang, even inside an "eval BLOCK" with and using "alarm". In
730 these extreme cases you have no choice but to skip over the broken
731 tests entirely.
732
733 The syntax and behavior is similar to a "SKIP: BLOCK" except the
734 tests will be marked as failing but todo. Test::Harness will
735 interpret them as passing.
736
737 When do I use SKIP vs. TODO?
738 If it's something the user might not be able to do, use SKIP. This
739 includes optional modules that aren't installed, running under an
740 OS that doesn't have some feature (like fork() or symlinks), or
741 maybe you need an Internet connection and one isn't available.
742
743 If it's something the programmer hasn't done yet, use TODO. This
744 is for any code you haven't written yet, or bugs you have yet to
745 fix, but want to put tests in your testing script (always a good
746 idea).
747
748 Test control
749 BAIL_OUT
750 BAIL_OUT($reason);
751
752 Indicates to the harness that things are going so badly all testing
753 should terminate. This includes the running of any additional test
754 scripts.
755
756 This is typically used when testing cannot continue such as a
757 critical module failing to compile or a necessary external utility
758 not being available such as a database connection failing.
759
760 The test will exit with 255.
761
762 For even better control look at Test::Most.
763
764 Discouraged comparison functions
765 The use of the following functions is discouraged as they are not
766 actually testing functions and produce no diagnostics to help figure
767 out what went wrong. They were written before is_deeply() existed
768 because I couldn't figure out how to display a useful diff of two
769 arbitrary data structures.
770
771 These functions are usually used inside an ok().
772
773 ok( eq_array(\@got, \@expected) );
774
775 "is_deeply()" can do that better and with diagnostics.
776
777 is_deeply( \@got, \@expected );
778
779 They may be deprecated in future versions.
780
781 eq_array
782 my $is_eq = eq_array(\@got, \@expected);
783
784 Checks if two arrays are equivalent. This is a deep check, so
785 multi-level structures are handled correctly.
786
787 eq_hash
788 my $is_eq = eq_hash(\%got, \%expected);
789
790 Determines if the two hashes contain the same keys and values.
791 This is a deep check.
792
793 eq_set
794 my $is_eq = eq_set(\@got, \@expected);
795
796 Similar to eq_array(), except the order of the elements is not
797 important. This is a deep check, but the irrelevancy of order only
798 applies to the top level.
799
800 ok( eq_set(\@got, \@expected) );
801
802 Is better written:
803
804 is_deeply( [sort @got], [sort @expected] );
805
806 NOTE By historical accident, this is not a true set comparison.
807 While the order of elements does not matter, duplicate elements do.
808
809 NOTE eq_set() does not know how to deal with references at the top
810 level. The following is an example of a comparison which might not
811 work:
812
813 eq_set([\1, \2], [\2, \1]);
814
815 Test::Deep contains much better set comparison functions.
816
817 Extending and Embedding Test::More
818 Sometimes the Test::More interface isn't quite enough. Fortunately,
819 Test::More is built on top of Test::Builder which provides a single,
820 unified backend for any test library to use. This means two test
821 libraries which both use Test::Builder can be used together in the same
822 program.
823
824 If you simply want to do a little tweaking of how the tests behave, you
825 can access the underlying Test::Builder object like so:
826
827 builder
828 my $test_builder = Test::More->builder;
829
830 Returns the Test::Builder object underlying Test::More for you to
831 play with.
832
834 If all your tests passed, Test::Builder will exit with zero (which is
835 normal). If anything failed it will exit with how many failed. If you
836 run less (or more) tests than you planned, the missing (or extras) will
837 be considered failures. If no tests were ever run Test::Builder will
838 throw a warning and exit with 255. If the test died, even after having
839 successfully completed all its tests, it will still be considered a
840 failure and will exit with 255.
841
842 So the exit codes are...
843
844 0 all tests successful
845 255 test died or all passed but wrong # of tests run
846 any other number how many failed (including missing or extras)
847
848 If you fail more than 254 tests, it will be reported as 254.
849
850 NOTE This behavior may go away in future versions.
851
853 Backwards compatibility
854 Test::More works with Perls as old as 5.6.0.
855
856 utf8 / "Wide character in print"
857 If you use utf8 or other non-ASCII characters with Test::More you
858 might get a "Wide character in print" warning. Using "binmode
859 STDOUT, ":utf8"" will not fix it. Test::Builder (which powers
860 Test::More) duplicates STDOUT and STDERR. So any changes to them,
861 including changing their output disciplines, will not be seem by
862 Test::More.
863
864 The work around is to change the filehandles used by Test::Builder
865 directly.
866
867 my $builder = Test::More->builder;
868 binmode $builder->output, ":utf8";
869 binmode $builder->failure_output, ":utf8";
870 binmode $builder->todo_output, ":utf8";
871
872 Overloaded objects
873 String overloaded objects are compared as strings (or in cmp_ok()'s
874 case, strings or numbers as appropriate to the comparison op).
875 This prevents Test::More from piercing an object's interface
876 allowing better blackbox testing. So if a function starts
877 returning overloaded objects instead of bare strings your tests
878 won't notice the difference. This is good.
879
880 However, it does mean that functions like is_deeply() cannot be
881 used to test the internals of string overloaded objects. In this
882 case I would suggest Test::Deep which contains more flexible
883 testing functions for complex data structures.
884
885 Threads
886 Test::More will only be aware of threads if "use threads" has been
887 done before Test::More is loaded. This is ok:
888
889 use threads;
890 use Test::More;
891
892 This may cause problems:
893
894 use Test::More
895 use threads;
896
897 5.8.1 and above are supported. Anything below that has too many
898 bugs.
899
901 This is a case of convergent evolution with Joshua Pritikin's Test
902 module. I was largely unaware of its existence when I'd first written
903 my own ok() routines. This module exists because I can't figure out
904 how to easily wedge test names into Test's interface (along with a few
905 other problems).
906
907 The goal here is to have a testing utility that's simple to learn,
908 quick to use and difficult to trip yourself up with while still
909 providing more flexibility than the existing Test.pm. As such, the
910 names of the most common routines are kept tiny, special cases and
911 magic side-effects are kept to a minimum. WYSIWYG.
912
914 Test::Simple if all this confuses you and you just want to write some
915 tests. You can upgrade to Test::More later (it's forward compatible).
916
917 Test::Harness is the test runner and output interpreter for Perl. It's
918 the thing that powers "make test" and where the "prove" utility comes
919 from.
920
921 Test::Legacy tests written with Test.pm, the original testing module,
922 do not play well with other testing libraries. Test::Legacy emulates
923 the Test.pm interface and does play well with others.
924
925 Test::Differences for more ways to test complex data structures. And
926 it plays well with Test::More.
927
928 Test::Class is like xUnit but more perlish.
929
930 Test::Deep gives you more powerful complex data structure testing.
931
932 Test::Inline shows the idea of embedded testing.
933
934 Bundle::Test installs a whole bunch of useful test modules.
935
937 Michael G Schwern <schwern@pobox.com> with much inspiration from Joshua
938 Pritikin's Test module and lots of help from Barrie Slaymaker, Tony
939 Bowden, blackstar.co.uk, chromatic, Fergal Daly and the perl-qa gang.
940
942 See http://rt.cpan.org to report and view bugs.
943
945 The source code repository for Test::More can be found at
946 http://github.com/schwern/test-more/.
947
949 Copyright 2001-2008 by Michael G Schwern <schwern@pobox.com>.
950
951 This program is free software; you can redistribute it and/or modify it
952 under the same terms as Perl itself.
953
954 See http://www.perl.com/perl/misc/Artistic.html
955
956
957
958perl v5.16.3 2011-02-23 Test::More(3)