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NAME

Test::Vars - Detects unused variables in perl modules

VERSION

This document describes Test::Vars version 0.017.

SYNOPSIS

    use Test::Vars;

    # Check all libs that are listed in the MANIFEST file
    all_vars_ok();

    # Check an arbitrary file
    vars_ok('t/lib/MyLib.pm');

    # Ignore some variables while checking
    vars_ok 't/lib/MyLib2.pm', ignore_vars => [ '$an_unused_var' ];

DESCRIPTION

Test::Vars provides test functions to report unused variables either in an entire distribution or in some files of your choice in order to keep your source code tidy.

INTERFACE

Exported

all_vars_ok(%args)

Tests libraries in your distribution with %args.

libraries are collected from the MANIFEST file.

If you want to ignore variables, for example $foo, you can tell it to the test routines:

ignore_vars => { '$foo' => 1 }
ignore_vars => [qw($foo)]
ignore_if => sub{ $_ eq '$foo' }

Note that $self will be ignored by default unless you pass explicitly { '$self' => 0 } to ignore_vars.

vars_ok($lib, %args)

Tests $lib with %args.

See all_vars_ok.

test_vars($lib, $result_handler, %args)

This subroutine tests variables, but instead of outputting TAP, calls the $result_handler subroutine reference provided with the results of the test.

The $result_handler sub will be called once, with the following arguments:

  • $filename

    The file that was checked for unused variables.

  • $exit_code

    The value of $? from the child process that actually did the tests. This will be 0 if the tests passed.

  • $results

    This is an array reference which in turn contains zero or more array references. Each of those references contains two elements, a Test::Builder method, either diag or note, and a message.

    If the method is diag, the message contains an actual error. If the method is notes, the message contains extra information about the test, but is not indicative of an error.

MECHANISM

Test::Vars is similar to a part of Test::Perl::Critic, but the mechanism is different.

While Perl::Critic, the backend of Test::Perl::Critic, scans the source code as text, this modules scans the compiled opcodes (or AST: abstract syntax tree) using the B module. See also B and its submodules.

CONFIGURATION

TEST_VERBOSE = 1 | 2 shows the way this module works.

CAVEATS

Over time there have been reported a number of cases where Test-Vars fails to report unused variables. You can review most of these cases by going to our issue tracker on GitHub and selecting issues with the Bug label: https://github.com/houseabsolute/p5-Test-Vars/issues?q=is%3Aopen+is%3Aissue+label%3ABug

DEPENDENCIES

Perl 5.10.0 or later.

BUGS

Please report new issues at our issue tracker on GitHub: https://github.com/houseabsolute/p5-Test-Vars/issues. We no longer use rt.cpan.org for bug reports.

SEE ALSO

Perl::Critic

warnings::unused

B

Test::Builder::Module

AUTHOR

Goro Fuji (gfx) <gfuji(at)cpan.org>

LICENSE AND COPYRIGHT

Copyright (c) 2010, Goro Fuji (gfx). All rights reserved.

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself. See perlartistic for details.