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perl-Devel-Cover - Code coverage metrics for Perl… more info»
NAME Devel::Cover - Code coverage metrics for Perl SYNOPSIS To get coverage for an uninstalled module: cover -test or cover -delete HARNESS_PERL_SWITCHES=-MDevel::Cover make test cover To get coverage for an uninstalled module which uses Module::Build (0.26 or later): ./Build testcover If the module does not use the t/*.t framework: PERL5OPT=-MDevel::Cover make test If you want to get coverage for a program: perl -MDevel::Cover yourprog args cover perl -MDevel::Cover=-db,cover_db,-coverage,statement,time yourprog args DESCRIPTION This module provides code coverage metrics for Perl. Code coverage metrics describe how thoroughly tests exercise code. By using Devel::Cover you can discover areas of code not exercised by your tests and determine which tests to create to increase coverage. Code coverage can be considered as an indirect measure of quality. Although it is still being developed, Devel::Cover is now quite stable and provides many of the features to be expected in a useful coverage tool. Statement, branch, condition, subroutine, and pod coverage information is reported. Statement coverage data should be reasonable. Branch and condition coverage data should be mostly accurate too, although not always what one might initially expect. Subroutine coverage should be as accurate as statement coverage. Pod coverage comes from Pod::Coverage. If Pod::Coverage::CountParents is available it will be used instead. Coverage data for other criteria are not yet collected. The cover program can be used to generate coverage reports. Devel::Cover ships with a number of different reports including various types of HTML output, textual reports, a report to display missing coverage in the same format as compilation errors and a report to display coverage information within the Vim editor. It is possible to add annotations to reports, for example you could add a column to an HTML report showing who last changed a line, as determined by git blame. Some annotation modules are shipped with Devel::Cover and you can easily create your own. The gcov2perl program can be used to convert gcov files to "Devel::Cover" databases. This allows you to display your C or XS code coverage together with your Perl coverage, or to use any of the Devel::Cvoer reports to display your C coverage data. You may find that the coverage results don't match your expectations. This could be due to a bug in Devel::Cover, but code coverage can be unintuitive to newcomers, and especially so with Perl, so you may want to reconsider your expectations as well. Code coverage data are collected by replacing perl ops with functions which count how many times the ops are executed. These data are then mapped back to reality using the B compiler modules. There is also a statement profiling facility which should not be relied on. For proper profiling use Devel::NYTProf. Previous versions of Devel::Cover collected coverage data by replacing perl's runops function. It is still possible to switch to that mode of operation, but this now gets little testing and will probably be removed soon. You probably don't care about any of this. The most appropriate mailing list on which to discuss this module would be perl-qa. Discussion has migrated there from perl-qa-metrics which is now defunct. See <http://lists.perl.org/list/perl-qa.html>. The Devel::Cover repository can be found at <http://github.com/pjcj/Devel--Cover>.