oracular (3) Test::Perl::Critic::Progressive.3pm.gz
NAME
Test::Perl::Critic::Progressive - Gradually enforce coding standards.
SYNOPSIS
To test one or more files, and/or all files in one or more directories:
use Test::Perl::Critic::Progressive qw( progressive_critic_ok );
progressive_critic_ok($file1, $file2, $dir1, $dir2);
To test all Perl files in a distribution:
use Test::Perl::Critic::Progressive qw( progressive_critic_ok );
progressive_critic_ok();
Recommended usage for public CPAN distributions:
use strict;
use warnings;
use Test::More;
eval { require Test::Perl::Critic::Progressive };
plan skip_all => 'T::P::C::Progressive required for this test' if $@;
Test::Perl::Critic::Progressive::progressive_critic_ok();
DESCRIPTION
Applying coding standards to large amounts of legacy code is a daunting task. Often times, legacy code
is so non-compliant that it seems downright impossible. But, if you consistently chip away at the
problem, you will eventually succeed! Test::Perl::Critic::Progressive uses the Perl::Critic engine to
prevent further deterioration of your code and gradually steer it towards conforming with your chosen
coding standards.
The most effective way to use Test::Perl::Critic::Progressive is as a unit test that is run under a
continuous-integration system like CruiseControl or AntHill. Each time a developer commits changes to
the code, this test will fail and the build will break unless it has the same (or fewer) Perl::Critic
violations than the last successful test.
See the "NOTES" for more details about how this test works.
SUBROUTINES
All of the following subroutines can be exported upon request. Or you can export all of them at once
using the ':all' tag.
" progressive_critic_ok(@FILES [, @DIRECTORIES ]) "
" progressive_critic_ok() "
Uses Perl::Critic to analyze each of the given @FILES, and/or all Perl files beneath the given list
of @DIRECTORIES. If no arguments are given, it analyzes all the Perl files in the blib/ directory.
If the blib/ directory does not exist, then it tries the lib/, bin/, script/, and scripts/ directory.
The results of the analysis will be stored as .perlcritic-history in the same directory where your
test script is located.
The first time you run this test, it will always pass. But on each subsequent run, the test will
pass only if the number of violations found is less than or equal to the number of violations found
during the last passing test. If it does pass, then the history file will be updated with the new
analysis results. Once all the violations are removed from the code, this test will always pass,
unless a new violation is introduced.
This subroutine emits its own Test::More plan, so you do not need to specify an expected number of
tests yourself.
" get_history_file() "
" set_history_file($FILE) "
These functions get or set the full path to the history file. This is where
Test::Perl::Critic::Progressive will store the results of each passing analysis. If the $FILE does
not exist, it will be created anew. The default is "$Bin/.perlcritic-history" where $Bin is the
directory that the calling test script is located in.
" get_total_step_size() "
" set_total_step_size($INTEGER) "
These functions get or set the minimum acceptable decrease in the total number of violations between
each test. The default value is zero, which means that you are not required to remove any
violations, but you are also not allowed to add any. If you set the step size to a positive number,
the test will require you to remove $INTEGER violations each time the test is run. In this case, the
particular type of violation that you eliminate doesn't matter. The larger the step size, the faster
you'll have to eliminate violations.
" get_step_size_per_policy() "
" set_step_size_per_policy(%ARGS) "
These functions get or set the minimum acceptable decrease in the number of violations of a specific
policy between each test. The %ARGS should be "$POLICY_NAME => $INTEGER" pairs, like this:
my %step_sizes = (
'ValuesAndExpressions::ProhibitLeadingZeros' => 2,
'Variables::ProhibitConditionalDeclarations' => 1,
'InputOutput::ProhibitTwoArgOpen' => 3,
);
set_step_size_per_policy( %step_sizes );
progressive_critic_ok();
The default step size for any given Policy is zero, which means that you are not required to remove
any violations, but you are also not allowed to add any. But if you wish to focus on eliminating
certain types of violations, then increasing the per-policy step size will force you to decrease the
number of violations of that particular Policy, while ignoring other types of violations. The larger
the step size, the faster you'll have to eliminate violations.
" get_critic_args() "
" set_critic_args(%ARGS) "
These functions get or set the arguments given to Perl::Critic. By default,
Test::Perl::Critic::Progressive invokes Perl::Critic with its default configuration. But if you have
developed your code against a custom Perl::Critic configuration, you will want to configure this test
to do the same.
Any %ARGS given to "set_critic_args" will be passed directly into the Perl::Critic constructor. So
if you have developed your code using a custom .perlcriticrc file, you can direct
Test::Perl::Critic::Progressive to use a custom file too.
use Test::Perl::Critic::Progressive ( ':all' );
set_critic_args(-profile => 't/perlcriticrc);
progressive_critic_ok();
Now place a copy of your own .perlcriticrc file in the distribution as t/perlcriticrc. Now,
"progressive_critic_ok" will use this same Perl::Critic configuration. See the Perl::Critic
documentation for details on the .perlcriticrc file format.
Any argument that is supported by the Perl::Critic constructor can be passed through this interface.
For example, you can also set the minimum severity level, or include & exclude specific policies like
this:
use Test::Perl::Critic::Progressive ( ':all' );
set_critic_args( -severity => 2, -exclude => ['MixedCaseVars'] );
progressive_critic_ok();
See the Perl::Critic documentation for complete details on its options and arguments.
NOTES
The test is evaluated in two ways. First, the number of violations for each Policy must be less than or
equal to the number of the violations found during the last passing test, minus the step size for that
Policy. Second, the total number of violations must be less than or equal the total number of violations
found during the last passing test, minus the total step size. This prevents you from simply
substituting one kind of violation for another.
You can use the total step size and the per-policy step size at the same time. For example, you can set
the total step size to 5, and set the per-policy step size for the
"TestingAndDebugging::RequireStrictures" Policy to 3. In which case, you'll have to remove 5 violations
between each test, but 3 of them must be violations of "TestingAndDebugging::RequireStrictures".
Over time, you'll probably add new Policies to your Perl::Critic setup. When
Test::Perl::Critic::Progressive uses a Policy for the first time, any newly discovered violations of that
Policy will not be considered in the test. However, they will be considered in subsequent tests.
If you are building a CPAN distribution, you'll want to add ^t/.perlcritic-history$ to the MANIFEST.SKIP
file. And if you are using a revision control system like CVS or Subversion, you'll probably want to
configure it to ignore the t/.perlcritic-history file as well.
BUGS
If you find any bugs, please submit them to
<http://rt.cpan.org/NoAuth/Bugs.html?Dist=Test-Perl-Critic-Progressive>. Thanks.
SEE ALSO
criticism
Perl::Critic
Test::Perl::Critic
<http://www.perlcritic.com>
AUTHOR
Jeffrey Ryan Thalhammer <thaljef@cpan.org>
COPYRIGHT
Copyright (c) 2007-2008 Jeffrey Ryan Thalhammer. All rights reserved.
This program is free software; you can redistribute it and/or modify it under the same terms as Perl
itself. The full text of this license can be found in the LICENSE file included with this module.