NAME

    App::Yath - Yet Another Test Harness (Test2-Harness) Command Line
    Interface (CLI)

DESCRIPTION

    This is the primary documentation for yath, App::Yath, Test2::Harness.

    The canonical source of up-to-date command options are the help output
    when using $ yath help and $ yath help COMMAND.

    This document is mainly an overview of yath usage and common recipes.

    App::Yath is an alternative to App::Prove, and Test2::Harness is an
    alternative to Test::Harness. It is not designed to replace
    Test::Harness/prove. Test2::Harness is designed to take full advantage
    of the rich data Test2 can provide. Test2::Harness is also able to use
    non-core modules and provide more functionality than prove can achieve
    with its restrictions.

PLATFORM SUPPORT

    Test2::Harness/App::Yath is is focused on unix-like platforms. Most
    development happens on linux, but bsd, macos, etc should work fine as
    well.

    Patches are welcome for any/all platforms, but the primary author (Chad
    'Exodist' Granum) does not directly develop against non-unix platforms.

 WINDOWS

    Currently windows is not supported, and it is known that the package
    will not install on windows. Patches are be welcome, and it would be
    great if someone wanted to take on the windows-support role, but it is
    not a primary goal for the project.

OVERVIEW

    To use Test2::Harness, you use the yath command. Yath will find the
    tests (or use the ones you specify) and run them. As it runs, it will
    output diagnostic information such as failures. At the end, yath will
    print a summary of the test run.

    yath can be thought of as a more powerful alternative to prove
    (Test::Harness)

RECIPES

    These are common recipes for using yath.

 RUN PROJECT TESTS

        $ yath

    Simply running yath with no arguments means "Run all tests for the
    current project". Yath will look for tests in ./t, ./t2, and ./test.pl
    and run any which are found.

    Normally this implies the test command but will instead imply the run
    command if a persistent test runner is detected.

 PRELOAD MODULES

    Yath has the ability to preload modules. Yath normally forks to start
    new tests, so preloading can reduce the time spent loading modules over
    and over in each test.

    Note that some tests may depend on certain modules not being loaded. In
    these cases you can add the # HARNESS-NO-PRELOAD directive to the top
    of the test files that cannot use preload.

  SIMPLE PRELOAD

    Any module can be preloaded:

        $ yath -PMoose

    You can preload as many modules as you want:

        $ yath -PList::Util -PScalar::Util

  COMPLEX PRELOAD

    If your preload is a subclass of Test2::Harness::Runner::Preload then
    more complex preload behavior is possible. See those docs for more
    info.

 LOGGING

  RECORDING A LOG

    You can turn on logging with a flag. The filename of the log will be
    printed at the end.

        $ yath -L
        ...
        Wrote log file: test-logs/2017-09-12~22:44:34~1505281474~25709.jsonl

    The event log can be quite large. It can be compressed with bzip2.

        $ yath -B
        ...
        Wrote log file: test-logs/2017-09-12~22:44:34~1505281474~25709.jsonl.bz2

    gzip compression is also supported.

        $ yath -G
        ...
        Wrote log file: test-logs/2017-09-12~22:44:34~1505281474~25709.jsonl.gz

    -B and -G both imply -L.

  REPLAYING FROM A LOG

    You can replay a test run from a log file:

        $ yath test-logs/2017-09-12~22:44:34~1505281474~25709.jsonl.bz2

    This will be significantly faster than the initial run as no tests are
    actually being executed. All events are simply read from the log, and
    processed by the harness.

    You can change display options and limit rendering/processing to
    specific test jobs from the run:

        $ yath test-logs/2017-09-12~22:44:34~1505281474~25709.jsonl.bz2 -v [TEST UUID(S)]

    Note: This is done using the $ yath replay ... command. The replay
    command is implied if the first argument is a log file.

 PER-TEST TIMING DATA

    The -T option will cause each test file to report how long it took to
    run.

        $ yath -T
    
        ( PASSED )  job  1    t/yath_script.t
        (  TIME  )  job  1    Startup: 0.07692s | Events: 0.01170s | Cleanup: 0.00190s | Total: 0.09052s

 PERSISTENT RUNNER

    yath supports starting a yath session that waits for tests to run. This
    is very useful when combined with preload.

  STARTING

    This starts the server. Many options available to the 'test' command
    will work here but not all. See $ yath help start for more info.

        $ yath start

  RUNNING

    This will run tests using the persistent runner. By default, it will
    search for tests just like the 'test' command. Many options available
    to the test command will work for this as well. See $ yath help run for
    more details.

        $ yath run

  STOPPING

    Stopping a persistent runner is easy.

        $ yath stop

  INFORMATIONAL

    The which command will tell you which persistent runner will be used.
    Yath searches for the persistent runner in the current directory, then
    searches in parent directories until it either hits the root directory,
    or finds the persistent runner tracking file.

        $ yath which

    The watch command will tail the runner's log files.

        $ yath watch

  PRELOAD + PERSISTENT RUNNER

    You can use preloads with the yath start command. In this case, yath
    will track all the modules pulled in during preload. If any of them
    change, the server will reload itself to bring in the changes. Further,
    modified modules will be blacklisted so that they are not preloaded on
    subsequent reloads. This behavior is useful if you are actively working
    on a module that is normally preloaded.

 MAKING YOUR PROJECT ALWAYS USE YATH

        $ yath init

    The above command will create test.pl. test.pl is automatically run by
    most build utils, in which case only the exit value matters. The
    generated test.pl will run yath and execute all tests in the ./t and/or
    ./t2 directories. Tests in ./t will ALSO be run by prove but tests in
    ./t2 will only be run by yath.

 PROJECT-SPECIFIC YATH CONFIG

    You can write a .yath.rc file. The file format is very simple. Create a
    [COMMAND] section to start the configuration for a command and then
    provide any options normally allowed by it. When yath is run inside
    your project, it will use the config specified in the rc file, unless
    overridden by command line options.

    Note: You can also add pre-command options by placing them at the top
    of your config file BEFORE any [cmd] markers.

    Comments start with a semi-colon.

    Example .yath.rc:

        -pFoo ; Load the 'foo' plugin before dealing with commands.
    
        [test]
        -B ;Always write a bzip2-compressed log
    
        [start]
        -PMoose ;Always preload Moose with a persistent runner

    This file is normally committed into the project's repo.

 PROJECT-SPECIFIC YATH CONFIG USER OVERRIDES

    You can add a .yath.user.rc file. Format is the same as the regular
    .yath.rc file. This file will be read in addition to the regular config
    file. Directives in this file will come AFTER the directives in the
    primary config so it may be used to override config.

    This file should not normally be committed to the project repo.

 HARNESS DIRECTIVES INSIDE TESTS

    yath will recognise a number of directive comments placed near the top
    of test files. These directives should be placed after the #! line but
    before any real code.

    Real code is defined as any line that does not start with use, require,
    BEGIN, package, or #

    good example 1

          #!/usr/bin/perl
          # HARNESS-NO-FORK
      
          ...

    good example 2

          #!/usr/bin/perl
          use strict;
          use warnings;
      
          # HARNESS-NO-FORK
      
          ...

    bad example 1

          #!/usr/bin/perl
      
          # blah
      
          # HARNESS-NO-FORK
      
          ...

    bad example 2

          #!/usr/bin/perl
      
          print "hi\n";
      
          # HARNESS-NO-FORK
      
          ...

  HARNESS-NO-PRELOAD

        #!/usr/bin/perl
        # HARNESS-NO-PRELOAD

    Use this if your test will fail when modules are preloaded. This will
    tell yath to start a new perl process to run the script instead of
    forking with preloaded modules.

    Currently this implies HARNESS-NO-FORK, but that may not always be the
    case.

  HARNESS-NO-FORK

        #!/usr/bin/perl
        # HARNESS-NO-FORK

    Use this if your test file cannot run in a forked process, but instead
    must be run directly with a new perl process.

    This implies HARNESS-NO-PRELOAD.

  HARNESS-NO-STREAM

    yath usually uses the Test2::Formatter::Stream formatter instead of
    TAP. Some tests depend on using a TAP formatter. This option will make
    yath use Test2::Formatter::TAP or Test::Builder::Formatter.

  HARNESS-NO-IO-EVENTS

    yath usually uses the Test2::Plugin::IOEvents plugin. This plugin
    replaces STDERR and STDOUT in your test with tied handles that fire off
    proper Test2::Event's when they are printed to. Most of the time this
    is not an issue, but any fancy tests or modules which do anything with
    STDERR or STDOUT other than print may have really messy errors.

    This directive will disable the plugin on a per-test basis.
    Alternatively you can use the --no-io-events option when running yath
    to disable it globally for your test suite.

  HARNESS-NO-TIMEOUT

    yath will usually kill a test if no events occur within a timeout
    (default 60 seconds). You can add this directive to tests that are
    expected to trip the timeout, but should be allowed to continue.

    NOTE: you usually are doing the wrong thing if you need to set this.
    See: HARNESS-TIMEOUT-EVENT.

  HARNESS-TIMEOUT-EVENT 60

    yath can be told to alter the default event timeout from 60 seconds to
    another value. This is the recommended alternative to
    HARNESS-NO-TIMEOUT

  HARNESS-TIMEOUT-POSTEXIT 15

    yath can be told to alter the default POSTEXIT timeout from 15 seconds
    to another value.

    Sometimes a test will fork producing output in the child while the
    parent is allowed to exit. In these cases we cannot rely on the
    original process exit to tell us when a test is complete. In cases
    where we have an exit, and partial output (assertions with no final
    plan, or a plan that has not been completed) we wait for a timeout
    period to see if any additional events come into

  HARNESS-DURATION-LONG

    This lets you tell yath that the test file is long-running. This is
    primarily used when concurrency is turned on in order to run longer
    tests earlier, and concurrently with shorter ones. There is also a yath
    option to skip all long tests.

    This duration is set automatically if HARNESS-NO-TIMEOUT is set.

  HARNESS-DURATION-MEDIUM

    This lets you tell yath that the test is medium.

    This is the default duration.

  HARNESS-DURATION-SHORT

    This lets you tell yath That the test is short.

  HARNESS-CATEGORY-ISOLATION

    This lets you tell yath that the test cannot be run concurrently with
    other tests. Yath will hold off and run these tests one at a time after
    all other tests.

  HARNESS-CATEGORY-IMMISCIBLE

    This lets you tell yath that the test cannot be run concurrently with
    other tests of this class. This is helpful when you have multiple tests
    which would otherwise have to be run sequentially at the end of the
    run.

    Yath prioritizes running these tests above HARNESS-CATEGORY-LONG.

  HARNESS-CATEGORY-GENERAL

    This is the default category.

  HARNESS-CONFLICTS-XXX

    This lets you tell yath that no other test of type XXX can be run at
    the same time as this one. You are able to set multiple conflict types
    and yath will honor them.

    XXX can be replaced with any type of your choosing.

    NOTE: This directive does not alter the category of your test. You are
    free to mark the test with LONG or MEDIUM in addition to this marker.

    Example with multiple lines.

          #!/usr/bin/perl
          # DASH and space are split the same way.
          # HARNESS-CONFLICTS-DAEMON
          # HARNESS-CONFLICTS  MYSQL
      
          ...

    Or on a single line.

          #!/usr/bin/perl
          # HARNESS-CONFLICTS DAEMON MYSQL
      
          ...

MODULE DOCS

    This section documents the App::Yath module itself.

 SYNOPSIS

    In practice you should never need to write your own yath script, or
    construct an App::Yath instance, or even access themain instance when
    yath is running. However some aspects of doing so are documented here
    for completeness.

    A minimum yath script looks like this:

        BEGIN {
            package App::Yath:Script;
    
            require Time::HiRes;
            require App::Yath;
            require Test2::Harness::Settings;
    
            my $settings = Test2::Harness::Settings->new(
                harness => {
                    orig_argv       => [@ARGV],
                    orig_inc        => [@INC],
                    script          => __FILE__,
                    start           => Time::HiRes::time(),
                    version         => $App::Yath::VERSION,
                },
            );
    
            my $app = App::Yath->new(
                argv    => \@ARGV,
                config  => {},
                settings => $settings,
            );
    
            $app->generate_run_sub('App::Yath::Script::run');
        }
    
        exit(App::Yath::Script::run());

    It is important that most logic live in a BEGIN block. This is so that
    goto::file can be used post-fork to execute a test script.

    The actual yath script is significantly more complicated with the
    following behaviors:

    pre-process essential arguments such as -D and no-scan-plugins

    re-exec with a different yath script if in developer mode and a local
    copy is found

    Parse the yath-rc config files

    gather and store essential startup information

 METHODS

    App::Yath does not provide many methods to use externally.

    $app->generate_run_sub($symbol_name)

      This tells App::Yath to generate a subroutine at the specified symbol
      name which can be run and be expected to return an exit value.

    $lib_path = $app->app_path()

      Get the include directory App::Yath was loaded from.

SOURCE

    The source code repository for Test2-Harness can be found at
    http://github.com/Test-More/Test2-Harness/.

MAINTAINERS

    Chad Granum <exodist@cpan.org>

AUTHORS

    Chad Granum <exodist@cpan.org>

COPYRIGHT

    Copyright 2020 Chad Granum <exodist7@gmail.com>.

    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/

