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diff --git a/chromium/third_party/cygwin/lib/perl5/5.10/Test/Tutorial.pod b/chromium/third_party/cygwin/lib/perl5/5.10/Test/Tutorial.pod deleted file mode 100644 index b730918c755..00000000000 --- a/chromium/third_party/cygwin/lib/perl5/5.10/Test/Tutorial.pod +++ /dev/null @@ -1,603 +0,0 @@ -=head1 NAME - -Test::Tutorial - A tutorial about writing really basic tests - -=head1 DESCRIPTION - - -I<AHHHHHHH!!!! NOT TESTING! Anything but testing! -Beat me, whip me, send me to Detroit, but don't make -me write tests!> - -I<*sob*> - -I<Besides, I don't know how to write the damned things.> - - -Is this you? Is writing tests right up there with writing -documentation and having your fingernails pulled out? Did you open up -a test and read - - ######## We start with some black magic - -and decide that's quite enough for you? - -It's ok. That's all gone now. We've done all the black magic for -you. And here are the tricks... - - -=head2 Nuts and bolts of testing. - -Here's the most basic test program. - - #!/usr/bin/perl -w - - print "1..1\n"; - - print 1 + 1 == 2 ? "ok 1\n" : "not ok 1\n"; - -since 1 + 1 is 2, it prints: - - 1..1 - ok 1 - -What this says is: C<1..1> "I'm going to run one test." [1] C<ok 1> -"The first test passed". And that's about all magic there is to -testing. Your basic unit of testing is the I<ok>. For each thing you -test, an C<ok> is printed. Simple. B<Test::Harness> interprets your test -results to determine if you succeeded or failed (more on that later). - -Writing all these print statements rapidly gets tedious. Fortunately, -there's B<Test::Simple>. It has one function, C<ok()>. - - #!/usr/bin/perl -w - - use Test::Simple tests => 1; - - ok( 1 + 1 == 2 ); - -and that does the same thing as the code above. C<ok()> is the backbone -of Perl testing, and we'll be using it instead of roll-your-own from -here on. If C<ok()> gets a true value, the test passes. False, it -fails. - - #!/usr/bin/perl -w - - use Test::Simple tests => 2; - ok( 1 + 1 == 2 ); - ok( 2 + 2 == 5 ); - -from that comes - - 1..2 - ok 1 - not ok 2 - # Failed test (test.pl at line 5) - # Looks like you failed 1 tests of 2. - -C<1..2> "I'm going to run two tests." This number is used to ensure -your test program ran all the way through and didn't die or skip some -tests. C<ok 1> "The first test passed." C<not ok 2> "The second test -failed". Test::Simple helpfully prints out some extra commentary about -your tests. - -It's not scary. Come, hold my hand. We're going to give an example -of testing a module. For our example, we'll be testing a date -library, B<Date::ICal>. It's on CPAN, so download a copy and follow -along. [2] - - -=head2 Where to start? - -This is the hardest part of testing, where do you start? People often -get overwhelmed at the apparent enormity of the task of testing a -whole module. Best place to start is at the beginning. Date::ICal is -an object-oriented module, and that means you start by making an -object. So we test C<new()>. - - #!/usr/bin/perl -w - - use Test::Simple tests => 2; - - use Date::ICal; - - my $ical = Date::ICal->new; # create an object - ok( defined $ical ); # check that we got something - ok( $ical->isa('Date::ICal') ); # and it's the right class - -run that and you should get: - - 1..2 - ok 1 - ok 2 - -congratulations, you've written your first useful test. - - -=head2 Names - -That output isn't terribly descriptive, is it? When you have two -tests you can figure out which one is #2, but what if you have 102? - -Each test can be given a little descriptive name as the second -argument to C<ok()>. - - use Test::Simple tests => 2; - - ok( defined $ical, 'new() returned something' ); - ok( $ical->isa('Date::ICal'), " and it's the right class" ); - -So now you'd see... - - 1..2 - ok 1 - new() returned something - ok 2 - and it's the right class - - -=head2 Test the manual - -Simplest way to build up a decent testing suite is to just test what -the manual says it does. [3] Let's pull something out of the -L<Date::ICal/SYNOPSIS> and test that all its bits work. - - #!/usr/bin/perl -w - - use Test::Simple tests => 8; - - use Date::ICal; - - $ical = Date::ICal->new( year => 1964, month => 10, day => 16, - hour => 16, min => 12, sec => 47, - tz => '0530' ); - - ok( defined $ical, 'new() returned something' ); - ok( $ical->isa('Date::ICal'), " and it's the right class" ); - ok( $ical->sec == 47, ' sec()' ); - ok( $ical->min == 12, ' min()' ); - ok( $ical->hour == 16, ' hour()' ); - ok( $ical->day == 17, ' day()' ); - ok( $ical->month == 10, ' month()' ); - ok( $ical->year == 1964, ' year()' ); - -run that and you get: - - 1..8 - ok 1 - new() returned something - ok 2 - and it's the right class - ok 3 - sec() - ok 4 - min() - ok 5 - hour() - not ok 6 - day() - # Failed test (- at line 16) - ok 7 - month() - ok 8 - year() - # Looks like you failed 1 tests of 8. - -Whoops, a failure! [4] Test::Simple helpfully lets us know on what line -the failure occurred, but not much else. We were supposed to get 17, -but we didn't. What did we get?? Dunno. We'll have to re-run the -test in the debugger or throw in some print statements to find out. - -Instead, we'll switch from B<Test::Simple> to B<Test::More>. B<Test::More> -does everything B<Test::Simple> does, and more! In fact, Test::More does -things I<exactly> the way Test::Simple does. You can literally swap -Test::Simple out and put Test::More in its place. That's just what -we're going to do. - -Test::More does more than Test::Simple. The most important difference -at this point is it provides more informative ways to say "ok". -Although you can write almost any test with a generic C<ok()>, it -can't tell you what went wrong. Instead, we'll use the C<is()> -function, which lets us declare that something is supposed to be the -same as something else: - - #!/usr/bin/perl -w - - use Test::More tests => 8; - - use Date::ICal; - - $ical = Date::ICal->new( year => 1964, month => 10, day => 16, - hour => 16, min => 12, sec => 47, - tz => '0530' ); - - ok( defined $ical, 'new() returned something' ); - ok( $ical->isa('Date::ICal'), " and it's the right class" ); - is( $ical->sec, 47, ' sec()' ); - is( $ical->min, 12, ' min()' ); - is( $ical->hour, 16, ' hour()' ); - is( $ical->day, 17, ' day()' ); - is( $ical->month, 10, ' month()' ); - is( $ical->year, 1964, ' year()' ); - -"Is C<$ical-E<gt>sec> 47?" "Is C<$ical-E<gt>min> 12?" With C<is()> in place, -you get some more information - - 1..8 - ok 1 - new() returned something - ok 2 - and it's the right class - ok 3 - sec() - ok 4 - min() - ok 5 - hour() - not ok 6 - day() - # Failed test (- at line 16) - # got: '16' - # expected: '17' - ok 7 - month() - ok 8 - year() - # Looks like you failed 1 tests of 8. - -letting us know that C<$ical-E<gt>day> returned 16, but we expected 17. A -quick check shows that the code is working fine, we made a mistake -when writing up the tests. Just change it to: - - is( $ical->day, 16, ' day()' ); - -and everything works. - -So any time you're doing a "this equals that" sort of test, use C<is()>. -It even works on arrays. The test is always in scalar context, so you -can test how many elements are in a list this way. [5] - - is( @foo, 5, 'foo has 5 elements' ); - - -=head2 Sometimes the tests are wrong - -Which brings us to a very important lesson. Code has bugs. Tests are -code. Ergo, tests have bugs. A failing test could mean a bug in the -code, but don't discount the possibility that the test is wrong. - -On the flip side, don't be tempted to prematurely declare a test -incorrect just because you're having trouble finding the bug. -Invalidating a test isn't something to be taken lightly, and don't use -it as a cop out to avoid work. - - -=head2 Testing lots of values - -We're going to be wanting to test a lot of dates here, trying to trick -the code with lots of different edge cases. Does it work before 1970? -After 2038? Before 1904? Do years after 10,000 give it trouble? -Does it get leap years right? We could keep repeating the code above, -or we could set up a little try/expect loop. - - use Test::More tests => 32; - use Date::ICal; - - my %ICal_Dates = ( - # An ICal string And the year, month, date - # hour, minute and second we expect. - '19971024T120000' => # from the docs. - [ 1997, 10, 24, 12, 0, 0 ], - '20390123T232832' => # after the Unix epoch - [ 2039, 1, 23, 23, 28, 32 ], - '19671225T000000' => # before the Unix epoch - [ 1967, 12, 25, 0, 0, 0 ], - '18990505T232323' => # before the MacOS epoch - [ 1899, 5, 5, 23, 23, 23 ], - ); - - - while( my($ical_str, $expect) = each %ICal_Dates ) { - my $ical = Date::ICal->new( ical => $ical_str ); - - ok( defined $ical, "new(ical => '$ical_str')" ); - ok( $ical->isa('Date::ICal'), " and it's the right class" ); - - is( $ical->year, $expect->[0], ' year()' ); - is( $ical->month, $expect->[1], ' month()' ); - is( $ical->day, $expect->[2], ' day()' ); - is( $ical->hour, $expect->[3], ' hour()' ); - is( $ical->min, $expect->[4], ' min()' ); - is( $ical->sec, $expect->[5], ' sec()' ); - } - -So now we can test bunches of dates by just adding them to -C<%ICal_Dates>. Now that it's less work to test with more dates, you'll -be inclined to just throw more in as you think of them. -Only problem is, every time we add to that we have to keep adjusting -the C<use Test::More tests =E<gt> ##> line. That can rapidly get -annoying. There's two ways to make this work better. - -First, we can calculate the plan dynamically using the C<plan()> -function. - - use Test::More; - use Date::ICal; - - my %ICal_Dates = ( - ...same as before... - ); - - # For each key in the hash we're running 8 tests. - plan tests => keys %ICal_Dates * 8; - -Or to be even more flexible, we use C<no_plan>. This means we're just -running some tests, don't know how many. [6] - - use Test::More 'no_plan'; # instead of tests => 32 - -now we can just add tests and not have to do all sorts of math to -figure out how many we're running. - - -=head2 Informative names - -Take a look at this line here - - ok( defined $ical, "new(ical => '$ical_str')" ); - -we've added more detail about what we're testing and the ICal string -itself we're trying out to the name. So you get results like: - - ok 25 - new(ical => '19971024T120000') - ok 26 - and it's the right class - ok 27 - year() - ok 28 - month() - ok 29 - day() - ok 30 - hour() - ok 31 - min() - ok 32 - sec() - -if something in there fails, you'll know which one it was and that -will make tracking down the problem easier. So try to put a bit of -debugging information into the test names. - -Describe what the tests test, to make debugging a failed test easier -for you or for the next person who runs your test. - - -=head2 Skipping tests - -Poking around in the existing Date::ICal tests, I found this in -F<t/01sanity.t> [7] - - #!/usr/bin/perl -w - - use Test::More tests => 7; - use Date::ICal; - - # Make sure epoch time is being handled sanely. - my $t1 = Date::ICal->new( epoch => 0 ); - is( $t1->epoch, 0, "Epoch time of 0" ); - - # XXX This will only work on unix systems. - is( $t1->ical, '19700101Z', " epoch to ical" ); - - is( $t1->year, 1970, " year()" ); - is( $t1->month, 1, " month()" ); - is( $t1->day, 1, " day()" ); - - # like the tests above, but starting with ical instead of epoch - my $t2 = Date::ICal->new( ical => '19700101Z' ); - is( $t2->ical, '19700101Z', "Start of epoch in ICal notation" ); - - is( $t2->epoch, 0, " and back to ICal" ); - -The beginning of the epoch is different on most non-Unix operating -systems [8]. Even though Perl smooths out the differences for the most -part, certain ports do it differently. MacPerl is one off the top of -my head. [9] We I<know> this will never work on MacOS. So rather than -just putting a comment in the test, we can explicitly say it's never -going to work and skip the test. - - use Test::More tests => 7; - use Date::ICal; - - # Make sure epoch time is being handled sanely. - my $t1 = Date::ICal->new( epoch => 0 ); - is( $t1->epoch, 0, "Epoch time of 0" ); - - SKIP: { - skip('epoch to ICal not working on MacOS', 6) - if $^O eq 'MacOS'; - - is( $t1->ical, '19700101Z', " epoch to ical" ); - - is( $t1->year, 1970, " year()" ); - is( $t1->month, 1, " month()" ); - is( $t1->day, 1, " day()" ); - - # like the tests above, but starting with ical instead of epoch - my $t2 = Date::ICal->new( ical => '19700101Z' ); - is( $t2->ical, '19700101Z', "Start of epoch in ICal notation" ); - - is( $t2->epoch, 0, " and back to ICal" ); - } - -A little bit of magic happens here. When running on anything but -MacOS, all the tests run normally. But when on MacOS, C<skip()> causes -the entire contents of the SKIP block to be jumped over. It's never -run. Instead, it prints special output that tells Test::Harness that -the tests have been skipped. - - 1..7 - ok 1 - Epoch time of 0 - ok 2 # skip epoch to ICal not working on MacOS - ok 3 # skip epoch to ICal not working on MacOS - ok 4 # skip epoch to ICal not working on MacOS - ok 5 # skip epoch to ICal not working on MacOS - ok 6 # skip epoch to ICal not working on MacOS - ok 7 # skip epoch to ICal not working on MacOS - -This means your tests won't fail on MacOS. This means less emails -from MacPerl users telling you about failing tests that you know will -never work. You've got to be careful with skip tests. These are for -tests which don't work and I<never will>. It is not for skipping -genuine bugs (we'll get to that in a moment). - -The tests are wholly and completely skipped. [10] This will work. - - SKIP: { - skip("I don't wanna die!"); - - die, die, die, die, die; - } - - -=head2 Todo tests - -Thumbing through the Date::ICal man page, I came across this: - - ical - - $ical_string = $ical->ical; - - Retrieves, or sets, the date on the object, using any - valid ICal date/time string. - -"Retrieves or sets". Hmmm, didn't see a test for using C<ical()> to set -the date in the Date::ICal test suite. So I'll write one. - - use Test::More tests => 1; - use Date::ICal; - - my $ical = Date::ICal->new; - $ical->ical('20201231Z'); - is( $ical->ical, '20201231Z', 'Setting via ical()' ); - -run that and I get - - 1..1 - not ok 1 - Setting via ical() - # Failed test (- at line 6) - # got: '20010814T233649Z' - # expected: '20201231Z' - # Looks like you failed 1 tests of 1. - -Whoops! Looks like it's unimplemented. Let's assume we don't have -the time to fix this. [11] Normally, you'd just comment out the test -and put a note in a todo list somewhere. Instead, we're going to -explicitly state "this test will fail" by wrapping it in a C<TODO> block. - - use Test::More tests => 1; - - TODO: { - local $TODO = 'ical($ical) not yet implemented'; - - my $ical = Date::ICal->new; - $ical->ical('20201231Z'); - - is( $ical->ical, '20201231Z', 'Setting via ical()' ); - } - -Now when you run, it's a little different: - - 1..1 - not ok 1 - Setting via ical() # TODO ical($ical) not yet implemented - # got: '20010822T201551Z' - # expected: '20201231Z' - -Test::More doesn't say "Looks like you failed 1 tests of 1". That '# -TODO' tells Test::Harness "this is supposed to fail" and it treats a -failure as a successful test. So you can write tests even before -you've fixed the underlying code. - -If a TODO test passes, Test::Harness will report it "UNEXPECTEDLY -SUCCEEDED". When that happens, you simply remove the TODO block with -C<local $TODO> and turn it into a real test. - - -=head2 Testing with taint mode. - -Taint mode is a funny thing. It's the globalest of all global -features. Once you turn it on, it affects I<all> code in your program -and I<all> modules used (and all the modules they use). If a single -piece of code isn't taint clean, the whole thing explodes. With that -in mind, it's very important to ensure your module works under taint -mode. - -It's very simple to have your tests run under taint mode. Just throw -a C<-T> into the C<#!> line. Test::Harness will read the switches -in C<#!> and use them to run your tests. - - #!/usr/bin/perl -Tw - - ...test normally here... - -So when you say C<make test> it will be run with taint mode and -warnings on. - - -=head1 FOOTNOTES - -=over 4 - -=item 1 - -The first number doesn't really mean anything, but it has to be 1. -It's the second number that's important. - -=item 2 - -For those following along at home, I'm using version 1.31. It has -some bugs, which is good -- we'll uncover them with our tests. - -=item 3 - -You can actually take this one step further and test the manual -itself. Have a look at B<Test::Inline> (formerly B<Pod::Tests>). - -=item 4 - -Yes, there's a mistake in the test suite. What! Me, contrived? - -=item 5 - -We'll get to testing the contents of lists later. - -=item 6 - -But what happens if your test program dies halfway through?! Since we -didn't say how many tests we're going to run, how can we know it -failed? No problem, Test::More employs some magic to catch that death -and turn the test into a failure, even if every test passed up to that -point. - -=item 7 - -I cleaned it up a little. - -=item 8 - -Most Operating Systems record time as the number of seconds since a -certain date. This date is the beginning of the epoch. Unix's starts -at midnight January 1st, 1970 GMT. - -=item 9 - -MacOS's epoch is midnight January 1st, 1904. VMS's is midnight, -November 17th, 1858, but vmsperl emulates the Unix epoch so it's not a -problem. - -=item 10 - -As long as the code inside the SKIP block at least compiles. Please -don't ask how. No, it's not a filter. - -=item 11 - -Do NOT be tempted to use TODO tests as a way to avoid fixing simple -bugs! - -=back - -=head1 AUTHORS - -Michael G Schwern E<lt>schwern@pobox.comE<gt> and the perl-qa dancers! - -=head1 COPYRIGHT - -Copyright 2001 by Michael G Schwern E<lt>schwern@pobox.comE<gt>. - -This documentation is free; you can redistribute it and/or modify it -under the same terms as Perl itself. - -Irrespective of its distribution, all code examples in these files -are hereby placed into the public domain. You are permitted and -encouraged to use this code in your own programs for fun -or for profit as you see fit. A simple comment in the code giving -credit would be courteous but is not required. - -=cut |