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.