Test2::Manual::Testing::Introduction(3) | Perl Programmers Reference Guide | Test2::Manual::Testing::Introduction(3) |
Test2::Manual::Testing::Introduction - Introduction to testing with Test2.
This tutorial is a beginners introduction to testing. This will take you through writing a test file, making assertions, and running your test.
Test files typically are placed inside the "t/" directory, and end with the ".t" file extension.
"t/example.t":
use Test2::V0; # Assertions will go here done_testing;
This is all the boilerplate you need.
You should always list bundles and tools directly. You should not simply list Test2::Suite and call it done, bundles and tools may be moved out of Test2::Suite to their own dists at any time.
Dist::Zilla
[Prereqs / TestRequires] Test2::V0 = 0.000060
ExtUtils::MakeMaker
my %WriteMakefileArgs = ( ..., "TEST_REQUIRES" => { "Test2::V0" => "0.000060" }, ... );
Module::Install
test_requires 'Test2::V0' => '0.000060';
Module::Build
my $build = Module::Build->new( ..., test_requires => { "Test2::V0" => "0.000060", }, ... );
The most simple tool for making assertions is ok(). ok() lets you assert that a condition is true.
ok($CONDITION, "Description of the condition");
Here is a complete "t/example.t":
use Test2::V0; ok(1, "1 is true, so this will pass"); done_testing;
Test files are simply scripts. Just like any other script you can run the test directly with perl. Another option is to use a test "harness" which runs the test for you, and provides extra information and checks the scripts exit value for you.
$ perl -Ilib t/example.t
Which should produce output like this:
# Seeded srand with seed '20161028' from local date. ok 1 - 1 is true, so this will pass 1..1
If the test had failed ("ok(0, ...)") it would look like this:
# Seeded srand with seed '20161028' from local date. not ok 1 - 0 is false, so this will fail 1..1
Test2 will also set the exit value of the script, a successful run will have an exit value of 0, a failed run will have a non-zero exit value.
The "yath" command line tool is provided by Test2::Harness which you may need to install yourself from cpan. "yath" is the harness written specifically for Test2.
$ yath -Ilib t/example.t
This will produce output similar to this:
( PASSED ) job 1 t/example.t ================================================================================ Run ID: 1508027909 All tests were successful!
You can also request verbose output with the "-v" flag:
$ yath -Ilib -v t/example.t
Which produces:
( LAUNCH ) job 1 example.t ( NOTE ) job 1 Seeded srand with seed '20171014' from local date. [ PASS ] job 1 + 1 is true, so this will pass [ PLAN ] job 1 Expected asserions: 1 ( PASSED ) job 1 example.t ================================================================================ Run ID: 1508028002 All tests were successful!
The "prove" command line tool is provided by the Test::Harness module which comes with most versions of perl. Test::Harness is dual-life, which means you can also install the latest version from cpan.
$ prove -Ilib t/example.t
This will produce output like this:
example.t .. ok All tests successful. Files=1, Tests=1, 0 wallclock secs ( 0.01 usr 0.00 sys + 0.05 cusr 0.00 csys = 0.06 CPU) Result: PASS
You can also request verbose output with the "-v" flag:
$ prove -Ilib -v t/example.t
The verbose output looks like this:
example.t .. # Seeded srand with seed '20161028' from local date. ok 1 - 1 is true, so this will pass 1..1 ok All tests successful. Files=1, Tests=1, 0 wallclock secs ( 0.02 usr 0.00 sys + 0.06 cusr 0.00 csys = 0.08 CPU) Result: PASS
All tests need a "plan". The job of a plan is to make sure you ran all the tests you expected. The plan prevents a passing result from a test that exits before all the tests are run.
There are 2 primary ways to set the plan:
plan() must be used before all assertions, or after all assertions, it cannot be done in the middle of making assertions.
The Test2::V0 bundle provides a lot more than ok(), plan(), and done_testing(). The biggest tools to note are:
is("foo", "foo", "Both strings are identical"); is(["foo", 1], ["foo", 1], "Both arrays contain the same elements");
like([1, 2, 3, 4], [1, 2, 3], "Passes, the extra element on the left is ignored");
You can also used regular expressions on the right hand side:
like("foo bar baz", qr/bar/, "The string matches the regex, this passes");
You can also nest the regexes:
like([1, 2, 'foo bar baz', 3], [1, 2, qr/bar/], "This passes");
Test2::Manual - Primary index of the manual.
The source code repository for Test2-Manual can be found at https://github.com/Test-More/Test2-Suite/.
Copyright 2018 Chad Granum <exodist@cpan.org>.
This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.
See http://dev.perl.org/licenses/
2024-04-28 | perl v5.40.0 |