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Test::More(3pm)	       Perl Programmers Reference Guide	       Test::More(3pm)

NAME
       Test::More - yet another framework for writing test scripts

SYNOPSIS
	 use Test::More tests => $Num_Tests;
	 # or
	 use Test::More qw(no_plan);
	 # or
	 use Test::More skip_all => $reason;

	 BEGIN { use_ok( 'Some::Module' ); }
	 require_ok( 'Some::Module' );

	 # Various ways to say "ok"
	 ok($this eq $that, $test_name);

	 is  ($this, $that,    $test_name);
	 isnt($this, $that,    $test_name);

	 # Rather than print STDERR "# here's what went wrong\n"
	 diag("here's what went wrong");

	 like  ($this, qr/that/, $test_name);
	 unlike($this, qr/that/, $test_name);

	 cmp_ok($this, '==', $that, $test_name);

	 is_deeply($complex_structure1, $complex_structure2, $test_name);

	 SKIP: {
	     skip $why, $how_many unless $have_some_feature;

	     ok( foo(),	      $test_name );
	     is( foo(42), 23, $test_name );
	 };

	 TODO: {
	     local $TODO = $why;

	     ok( foo(),	      $test_name );
	     is( foo(42), 23, $test_name );
	 };

	 can_ok($module, @methods);
	 isa_ok($object, $class);

	 pass($test_name);
	 fail($test_name);

	 BAIL_OUT($why);

	 # UNIMPLEMENTED!!!
	 my @status = Test::More::status;

DESCRIPTION
       STOP! If you're just getting started writing tests, have a look at
       Test::Simple first.  This is a drop in replacement for Test::Simple
       which you can switch to once you get the hang of basic testing.

       The purpose of this module is to provide a wide range of testing utili‐
       ties.  Various ways to say "ok" with better diagnostics, facilities to
       skip tests, test future features and compare complicated data struc‐
       tures.  While you can do almost anything with a simple "ok()" function,
       it doesn't provide good diagnostic output.

       I love it when a plan comes together

       Before anything else, you need a testing plan.  This basically declares
       how many tests your script is going to run to protect against premature
       failure.

       The preferred way to do this is to declare a plan when you "use
       Test::More".

	 use Test::More tests => $Num_Tests;

       There are rare cases when you will not know beforehand how many tests
       your script is going to run.  In this case, you can declare that you
       have no plan.  (Try to avoid using this as it weakens your test.)

	 use Test::More qw(no_plan);

       NOTE: using no_plan requires a Test::Harness upgrade else it will think
       everything has failed.  See "CAVEATS and NOTES").

       In some cases, you'll want to completely skip an entire testing script.

	 use Test::More skip_all => $skip_reason;

       Your script will declare a skip with the reason why you skipped and
       exit immediately with a zero (success).	See Test::Harness for details.

       If you want to control what functions Test::More will export, you have
       to use the 'import' option.  For example, to import everything but
       'fail', you'd do:

	 use Test::More tests => 23, import => ['!fail'];

       Alternatively, you can use the plan() function.	Useful for when you
       have to calculate the number of tests.

	 use Test::More;
	 plan tests => keys %Stuff * 3;

       or for deciding between running the tests at all:

	 use Test::More;
	 if( $^O eq 'MacOS' ) {
	     plan skip_all => 'Test irrelevant on MacOS';
	 }
	 else {
	     plan tests => 42;
	 }

       Test names

       By convention, each test is assigned a number in order.	This is
       largely done automatically for you.  However, it's often very useful to
       assign a name to each test.  Which would you rather see:

	 ok 4
	 not ok 5
	 ok 6

       or

	 ok 4 - basic multi-variable
	 not ok 5 - simple exponential
	 ok 6 - force == mass * acceleration

       The later gives you some idea of what failed.  It also makes it easier
       to find the test in your script, simply search for "simple exponen‐
       tial".

       All test functions take a name argument.	 It's optional, but highly
       suggested that you use it.

       I'm ok, you're not ok.

       The basic purpose of this module is to print out either "ok #" or "not
       ok #" depending on if a given test succeeded or failed.	Everything
       else is just gravy.

       All of the following print "ok" or "not ok" depending on if the test
       succeeded or failed.  They all also return true or false, respectively.

       ok
	     ok($this eq $that, $test_name);

	   This simply evaluates any expression ("$this eq $that" is just a
	   simple example) and uses that to determine if the test succeeded or
	   failed.  A true expression passes, a false one fails.  Very simple.

	   For example:

	       ok( $exp{9} == 81,		    'simple exponential' );
	       ok( Film->can('db_Main'),	    'set_db()' );
	       ok( $p->tests == 4,		    'saw tests' );
	       ok( !grep !defined $_, @items,	    'items populated' );

	   (Mnemonic:  "This is ok.")

	   $test_name is a very short description of the test that will be
	   printed out.	 It makes it very easy to find a test in your script
	   when it fails and gives others an idea of your intentions.
	   $test_name is optional, but we very strongly encourage its use.

	   Should an ok() fail, it will produce some diagnostics:

	       not ok 18 - sufficient mucus
	       #   Failed test 'sufficient mucus'
	       #   in foo.t at line 42.

	   This is actually Test::Simple's ok() routine.

       is
       isnt
	     is	 ( $this, $that, $test_name );
	     isnt( $this, $that, $test_name );

	   Similar to ok(), is() and isnt() compare their two arguments with
	   "eq" and "ne" respectively and use the result of that to determine
	   if the test succeeded or failed.  So these:

	       # Is the ultimate answer 42?
	       is( ultimate_answer(), 42,	   "Meaning of Life" );

	       # $foo isn't empty
	       isnt( $foo, '',	   "Got some foo" );

	   are similar to these:

	       ok( ultimate_answer() eq 42,	   "Meaning of Life" );
	       ok( $foo ne '',	   "Got some foo" );

	   (Mnemonic:  "This is that."	"This isn't that.")

	   So why use these?  They produce better diagnostics on failure.
	   ok() cannot know what you are testing for (beyond the name), but
	   is() and isnt() know what the test was and why it failed.  For
	   example this test:

	       my $foo = 'waffle';  my $bar = 'yarblokos';
	       is( $foo, $bar,	 'Is foo the same as bar?' );

	   Will produce something like this:

	       not ok 17 - Is foo the same as bar?
	       #   Failed test 'Is foo the same as bar?'
	       #   in foo.t at line 139.
	       #	  got: 'waffle'
	       #     expected: 'yarblokos'

	   So you can figure out what went wrong without rerunning the test.

	   You are encouraged to use is() and isnt() over ok() where possible,
	   however do not be tempted to use them to find out if something is
	   true or false!

	     # XXX BAD!
	     is( exists $brooklyn{tree}, 1, 'A tree grows in Brooklyn' );

	   This does not check if "exists $brooklyn{tree}" is true, it checks
	   if it returns 1.  Very different.  Similar caveats exist for false
	   and 0.  In these cases, use ok().

	     ok( exists $brooklyn{tree},    'A tree grows in Brooklyn' );

	   For those grammatical pedants out there, there's an "isn't()" func‐
	   tion which is an alias of isnt().

       like
	     like( $this, qr/that/, $test_name );

	   Similar to ok(), like() matches $this against the regex "qr/that/".

	   So this:

	       like($this, qr/that/, 'this is like that');

	   is similar to:

	       ok( $this =~ /that/, 'this is like that');

	   (Mnemonic "This is like that".)

	   The second argument is a regular expression.	 It may be given as a
	   regex reference (i.e. "qr//") or (for better compatibility with
	   older perls) as a string that looks like a regex (alternative
	   delimiters are currently not supported):

	       like( $this, '/that/', 'this is like that' );

	   Regex options may be placed on the end ('/that/i').

	   Its advantages over ok() are similar to that of is() and isnt().
	   Better diagnostics on failure.

       unlike
	     unlike( $this, qr/that/, $test_name );

	   Works exactly as like(), only it checks if $this does not match the
	   given pattern.

       cmp_ok
	     cmp_ok( $this, $op, $that, $test_name );

	   Halfway between ok() and is() lies cmp_ok().	 This allows you to
	   compare two arguments using any binary perl operator.

	       # ok( $this eq $that );
	       cmp_ok( $this, 'eq', $that, 'this eq that' );

	       # ok( $this == $that );
	       cmp_ok( $this, '==', $that, 'this == that' );

	       # ok( $this && $that );
	       cmp_ok( $this, '&&', $that, 'this && that' );
	       ...etc...

	   Its advantage over ok() is when the test fails you'll know what
	   $this and $that were:

	       not ok 1
	       #   Failed test in foo.t at line 12.
	       #     '23'
	       #	 &&
	       #     undef

	   It's also useful in those cases where you are comparing numbers and
	   is()'s use of "eq" will interfere:

	       cmp_ok( $big_hairy_number, '==', $another_big_hairy_number );

       can_ok
	     can_ok($module, @methods);
	     can_ok($object, @methods);

	   Checks to make sure the $module or $object can do these @methods
	   (works with functions, too).

	       can_ok('Foo', qw(this that whatever));

	   is almost exactly like saying:

	       ok( Foo->can('this') &&
		   Foo->can('that') &&
		   Foo->can('whatever')
		 );

	   only without all the typing and with a better interface.  Handy for
	   quickly testing an interface.

	   No matter how many @methods you check, a single can_ok() call
	   counts as one test.	If you desire otherwise, use:

	       foreach my $meth (@methods) {
		   can_ok('Foo', $meth);
	       }

       isa_ok
	     isa_ok($object, $class, $object_name);
	     isa_ok($ref,    $type,  $ref_name);

	   Checks to see if the given "$object->isa($class)".  Also checks to
	   make sure the object was defined in the first place.	 Handy for
	   this sort of thing:

	       my $obj = Some::Module->new;
	       isa_ok( $obj, 'Some::Module' );

	   where you'd otherwise have to write

	       my $obj = Some::Module->new;
	       ok( defined $obj && $obj->isa('Some::Module') );

	   to safeguard against your test script blowing up.

	   It works on references, too:

	       isa_ok( $array_ref, 'ARRAY' );

	   The diagnostics of this test normally just refer to 'the object'.
	   If you'd like them to be more specific, you can supply an
	   $object_name (for example 'Test customer').

       pass
       fail
	     pass($test_name);
	     fail($test_name);

	   Sometimes you just want to say that the tests have passed.  Usually
	   the case is you've got some complicated condition that is difficult
	   to wedge into an ok().  In this case, you can simply use pass() (to
	   declare the test ok) or fail (for not ok).  They are synonyms for
	   ok(1) and ok(0).

	   Use these very, very, very sparingly.

       Module tests

       You usually want to test if the module you're testing loads ok, rather
       than just vomiting if its load fails.  For such purposes we have
       "use_ok" and "require_ok".

       use_ok
	      BEGIN { use_ok($module); }
	      BEGIN { use_ok($module, @imports); }

	   These simply use the given $module and test to make sure the load
	   happened ok.	 It's recommended that you run use_ok() inside a BEGIN
	   block so its functions are exported at compile-time and prototypes
	   are properly honored.

	   If @imports are given, they are passed through to the use.  So
	   this:

	      BEGIN { use_ok('Some::Module', qw(foo bar)) }

	   is like doing this:

	      use Some::Module qw(foo bar);

	   Version numbers can be checked like so:

	      # Just like "use Some::Module 1.02"
	      BEGIN { use_ok('Some::Module', 1.02) }

	   Don't try to do this:

	      BEGIN {
		  use_ok('Some::Module');

		  ...some code that depends on the use...
		  ...happening at compile time...
	      }

	   because the notion of "compile-time" is relative.  Instead, you
	   want:

	     BEGIN { use_ok('Some::Module') }
	     BEGIN { ...some code that depends on the use... }

       require_ok
	      require_ok($module);
	      require_ok($file);

	   Like use_ok(), except it requires the $module or $file.

       Complex data structures

       Not everything is a simple eq check or regex.  There are times you need
       to see if two data structures are equivalent.  For these instances
       Test::More provides a handful of useful functions.

       NOTE I'm not quite sure what will happen with filehandles.

       is_deeply
	     is_deeply( $this, $that, $test_name );

	   Similar to is(), except that if $this and $that are references, it
	   does a deep comparison walking each data structure to see if they
	   are equivalent.  If the two structures are different, it will dis‐
	   play the place where they start differing.

	   is_deeply() compares the dereferenced values of references, the
	   references themselves (except for their type) are ignored.  This
	   means aspects such as blessing and ties are not considered "differ‐
	   ent".

	   is_deeply() current has very limited handling of function reference
	   and globs.  It merely checks if they have the same referent.	 This
	   may improve in the future.

	   Test::Differences and Test::Deep provide more in-depth functional‐
	   ity along these lines.

       Diagnostics

       If you pick the right test function, you'll usually get a good idea of
       what went wrong when it failed.	But sometimes it doesn't work out that
       way.  So here we have ways for you to write your own diagnostic mes‐
       sages which are safer than just "print STDERR".

       diag
	     diag(@diagnostic_message);

	   Prints a diagnostic message which is guaranteed not to interfere
	   with test output.  Like "print" @diagnostic_message is simply con‐
	   catenated together.

	   Handy for this sort of thing:

	       ok( grep(/foo/, @users), "There's a foo user" ) or
		   diag("Since there's no foo, check that /etc/bar is set up right");

	   which would produce:

	       not ok 42 - There's a foo user
	       #   Failed test 'There's a foo user'
	       #   in foo.t at line 52.
	       # Since there's no foo, check that /etc/bar is set up right.

	   You might remember "ok() or diag()" with the mnemonic "open() or
	   die()".

	   NOTE The exact formatting of the diagnostic output is still chang‐
	   ing, but it is guaranteed that whatever you throw at it it won't
	   interfere with the test.

       Conditional tests

       Sometimes running a test under certain conditions will cause the test
       script to die.  A certain function or method isn't implemented (such as
       fork() on MacOS), some resource isn't available (like a net connection)
       or a module isn't available.  In these cases it's necessary to skip
       tests, or declare that they are supposed to fail but will work in the
       future (a todo test).

       For more details on the mechanics of skip and todo tests see Test::Har‐
       ness.

       The way Test::More handles this is with a named block.  Basically, a
       block of tests which can be skipped over or made todo.  It's best if I
       just show you...

       SKIP: BLOCK
	     SKIP: {
		 skip $why, $how_many if $condition;

		 ...normal testing code goes here...
	     }

	   This declares a block of tests that might be skipped, $how_many
	   tests there are, $why and under what $condition to skip them.  An
	   example is the easiest way to illustrate:

	       SKIP: {
		   eval { require HTML::Lint };

		   skip "HTML::Lint not installed", 2 if $@;

		   my $lint = new HTML::Lint;
		   isa_ok( $lint, "HTML::Lint" );

		   $lint->parse( $html );
		   is( $lint->errors, 0, "No errors found in HTML" );
	       }

	   If the user does not have HTML::Lint installed, the whole block of
	   code won't be run at all.  Test::More will output special ok's
	   which Test::Harness interprets as skipped, but passing, tests.

	   It's important that $how_many accurately reflects the number of
	   tests in the SKIP block so the # of tests run will match up with
	   your plan.  If your plan is "no_plan" $how_many is optional and
	   will default to 1.

	   It's perfectly safe to nest SKIP blocks.  Each SKIP block must have
	   the label "SKIP", or Test::More can't work its magic.

	   You don't skip tests which are failing because there's a bug in
	   your program, or for which you don't yet have code written.	For
	   that you use TODO.  Read on.

       TODO: BLOCK
	       TODO: {
		   local $TODO = $why if $condition;

		   ...normal testing code goes here...
	       }

	   Declares a block of tests you expect to fail and $why.  Perhaps
	   it's because you haven't fixed a bug or haven't finished a new fea‐
	   ture:

	       TODO: {
		   local $TODO = "URI::Geller not finished";

		   my $card = "Eight of clubs";
		   is( URI::Geller->your_card, $card, 'Is THIS your card?' );

		   my $spoon;
		   URI::Geller->bend_spoon;
		   is( $spoon, 'bent',	  "Spoon bending, that's original" );
	       }

	   With a todo block, the tests inside are expected to fail.
	   Test::More will run the tests normally, but print out special flags
	   indicating they are "todo".	Test::Harness will interpret failures
	   as being ok.	 Should anything succeed, it will report it as an
	   unexpected success.	You then know the thing you had todo is done
	   and can remove the TODO flag.

	   The nice part about todo tests, as opposed to simply commenting out
	   a block of tests, is it's like having a programmatic todo list.
	   You know how much work is left to be done, you're aware of what
	   bugs there are, and you'll know immediately when they're fixed.

	   Once a todo test starts succeeding, simply move it outside the
	   block.  When the block is empty, delete it.

	   NOTE: TODO tests require a Test::Harness upgrade else it will treat
	   it as a normal failure.  See "CAVEATS and NOTES").

       todo_skip
	       TODO: {
		   todo_skip $why, $how_many if $condition;

		   ...normal testing code...
	       }

	   With todo tests, it's best to have the tests actually run.  That
	   way you'll know when they start passing.  Sometimes this isn't pos‐
	   sible.  Often a failing test will cause the whole program to die or
	   hang, even inside an "eval BLOCK" with and using "alarm".  In these
	   extreme cases you have no choice but to skip over the broken tests
	   entirely.

	   The syntax and behavior is similar to a "SKIP: BLOCK" except the
	   tests will be marked as failing but todo.  Test::Harness will
	   interpret them as passing.

       When do I use SKIP vs. TODO?
	   If it's something the user might not be able to do, use SKIP.  This
	   includes optional modules that aren't installed, running under an
	   OS that doesn't have some feature (like fork() or symlinks), or
	   maybe you need an Internet connection and one isn't available.

	   If it's something the programmer hasn't done yet, use TODO.	This
	   is for any code you haven't written yet, or bugs you have yet to
	   fix, but want to put tests in your testing script (always a good
	   idea).

       Test control

       BAIL_OUT
	       BAIL_OUT($reason);

	   Incidates to the harness that things are going so badly all testing
	   should terminate.  This includes the running any additional test
	   scripts.

	   This is typically used when testing cannot continue such as a crit‐
	   ical module failing to compile or a necessary external utility not
	   being available such as a database connection failing.

	   The test will exit with 255.

       Discouraged comparison functions

       The use of the following functions is discouraged as they are not actu‐
       ally testing functions and produce no diagnostics to help figure out
       what went wrong.	 They were written before is_deeply() existed because
       I couldn't figure out how to display a useful diff of two arbitrary
       data structures.

       These functions are usually used inside an ok().

	   ok( eq_array(\@this, \@that) );

       "is_deeply()" can do that better and with diagnostics.

	   is_deeply( \@this, \@that );

       They may be deprecated in future versions.

       eq_array
	     my $is_eq = eq_array(\@this, \@that);

	   Checks if two arrays are equivalent.	 This is a deep check, so
	   multi-level structures are handled correctly.

       eq_hash
	     my $is_eq = eq_hash(\%this, \%that);

	   Determines if the two hashes contain the same keys and values.
	   This is a deep check.

       eq_set
	     my $is_eq = eq_set(\@this, \@that);

	   Similar to eq_array(), except the order of the elements is not
	   important.  This is a deep check, but the irrelevancy of order only
	   applies to the top level.

	       ok( eq_set(\@this, \@that) );

	   Is better written:

	       is_deeply( [sort @this], [sort @that] );

	   NOTE By historical accident, this is not a true set comparison.
	   While the order of elements does not matter, duplicate elements do.

	   NOTE eq_set() does not know how to deal with references at the top
	   level.  The following is an example of a comparison which might not
	   work:

	       eq_set([\1, \2], [\2, \1]);

	   Test::Deep contains much better set comparison functions.

       Extending and Embedding Test::More

       Sometimes the Test::More interface isn't quite enough.  Fortunately,
       Test::More is built on top of Test::Builder which provides a single,
       unified backend for any test library to use.  This means two test
       libraries which both use Test::Builder can be used together in the same
       program.

       If you simply want to do a little tweaking of how the tests behave, you
       can access the underlying Test::Builder object like so:

       builder
	       my $test_builder = Test::More->builder;

	   Returns the Test::Builder object underlying Test::More for you to
	   play with.

EXIT CODES
       If all your tests passed, Test::Builder will exit with zero (which is
       normal).	 If anything failed it will exit with how many failed.	If you
       run less (or more) tests than you planned, the missing (or extras) will
       be considered failures.	If no tests were ever run Test::Builder will
       throw a warning and exit with 255.  If the test died, even after having
       successfully completed all its tests, it will still be considered a
       failure and will exit with 255.

       So the exit codes are...

	   0		       all tests successful
	   255		       test died or all passed but wrong # of tests run
	   any other number    how many failed (including missing or extras)

       If you fail more than 254 tests, it will be reported as 254.

       NOTE  This behavior may go away in future versions.

CAVEATS and NOTES
       Backwards compatibility
	   Test::More works with Perls as old as 5.004_05.

       Overloaded objects
	   String overloaded objects are compared as strings (or in cmp_ok()'s
	   case, strings or numbers as appropriate to the comparison op).
	   This prevents Test::More from piercing an object's interface allow‐
	   ing better blackbox testing.	 So if a function starts returning
	   overloaded objects instead of bare strings your tests won't notice
	   the difference.  This is good.

	   However, it does mean that functions like is_deeply() cannot be
	   used to test the internals of string overloaded objects.  In this
	   case I would suggest Test::Deep which contains more flexible test‐
	   ing functions for complex data structures.

       Threads
	   Test::More will only be aware of threads if "use threads" has been
	   done before Test::More is loaded.  This is ok:

	       use threads;
	       use Test::More;

	   This may cause problems:

	       use Test::More
	       use threads;

       Test::Harness upgrade
	   no_plan and todo depend on new Test::Harness features and fixes.
	   If you're going to distribute tests that use no_plan or todo your
	   end-users will have to upgrade Test::Harness to the latest one on
	   CPAN.  If you avoid no_plan and TODO tests, the stock Test::Harness
	   will work fine.

	   Installing Test::More should also upgrade Test::Harness.

HISTORY
       This is a case of convergent evolution with Joshua Pritikin's Test mod‐
       ule.  I was largely unaware of its existence when I'd first written my
       own ok() routines.  This module exists because I can't figure out how
       to easily wedge test names into Test's interface (along with a few
       other problems).

       The goal here is to have a testing utility that's simple to learn,
       quick to use and difficult to trip yourself up with while still provid‐
       ing more flexibility than the existing Test.pm.	As such, the names of
       the most common routines are kept tiny, special cases and magic side-
       effects are kept to a minimum.  WYSIWYG.

SEE ALSO
       Test::Simple if all this confuses you and you just want to write some
       tests.  You can upgrade to Test::More later (it's forward compatible).

       Test is the old testing module.	Its main benefit is that it has been
       distributed with Perl since 5.004_05.

       Test::Harness for details on how your test results are interpreted by
       Perl.

       Test::Differences for more ways to test complex data structures.	 And
       it plays well with Test::More.

       Test::Class is like XUnit but more perlish.

       Test::Deep gives you more powerful complex data structure testing.

       Test::Unit is XUnit style testing.

       Test::Inline shows the idea of embedded testing.

       Bundle::Test installs a whole bunch of useful test modules.

AUTHORS
       Michael G Schwern <schwern@pobox.com> with much inspiration from Joshua
       Pritikin's Test module and lots of help from Barrie Slaymaker, Tony
       Bowden, blackstar.co.uk, chromatic, Fergal Daly and the perl-qa gang.

BUGS
       See http://rt.cpan.org to report and view bugs.

COPYRIGHT
       Copyright 2001, 2002, 2004 by Michael G Schwern <schwern@pobox.com>.

       This program is free software; you can redistribute it and/or modify it
       under the same terms as Perl itself.

       See http://www.perl.com/perl/misc/Artistic.html

perl v5.8.8			  2001-09-21		       Test::More(3pm)
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Polarhome, production since 1999.
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Based on Fawad Halim's script.
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