Provided by: libdevel-cover-perl_1.31-1build1_amd64 bug


       cover - report coverage statistics


       version 1.31


        cover -test

        cover -report html_basic


       Report coverage statistics in a variety of formats.

       The summary option produces a short textual summary.  Other reports are available by using
       the report option.

       The following reports are currently available:

        html        - detailed HTML reports  (default)
        html_basic  - detailed HTML reports with syntax highlighting
        text        - detailed textual summary
        compilation - output in a format similar to Perl errors
        json        - output in a JSON format
        vim         - show coverage information in vim gutter


       The following command line options are supported:

        -h -help              - show help
        -i -info              - show documentation
        -v -version           - show version

        -silent               - don't print informational messages (default off)
        -summary              - give summary report                (default on)
        -report report_format - report format                      (default html)
        -outputdir dir        - directory for output               (default given db)
        -launch               - launch report in viewer (if avail) (default off)

        -select filename      - only report on the file            (default all)
        -ignore filename      - don't report on the file           (default none)
        -select_re RE         - append to REs of files to select   (default none)
        -ignore_re RE         - append to REs of files to ignore   (default none)
        -write [db]           - write the merged database          (default off)
        -delete               - drop database(s)                   (default off)
        -dump_db              - dump database(s) (for debugging)   (default off)

        -coverage criterion   - report on criterion  (default all available)

        -test                 - drop database(s) and run make test (default off)
        -gcov                 - run gcov to cover XS code     (default on if using gcc)
        -make make_prog       - use the given 'make' program for 'make test'
        -prefer_lib           - prefer files in lib                (default off)

        -add_uncoverable_point    string
        -delete_uncoverable_point string
        -uncoverable_file         file

        other options specific to the report format

        coverage_database [coverage_database ...]

       The "-report", "-select", "-ignore", "-select_re", "-ignore_re", and "-coverage" options
       may be specified multiple times.


       The following "-report" options are available in the core module.  Other reports may be
       available if they've been installed from external packages.

       html|html_minimal (default)
           HTML reporting. Percentage thresholds are colour-coded and configurable via -report_c0
           <integer>, -report_c1 <integer> and -report_c2 <integer>.:

               0%      75%      90%      100%
               |   ..   |   ..   |   ..   |
                  <c0      <c1      <c2   c3
                  red     yellow   orange green

           HTML reporting with syntax highlighting if PPI::HTML or Perl::Tidy module is detected.
           Like html|html_minimal reporting, percentage thresholds are colour-coded and

           Plain text reporting.

           A textual report in a format similar to that output by Perl itself such that the
           report may be used by your editor or other reporting tools to show where coverage is

           A report in JSON format.

       vim A report suitable for use with the vim editor to show coverage data in the sign


       Any number of coverage databases may be specified on the command line.  These databases
       will be merged and the reports will be based on the merged information.  If no databases
       are specified the default database (cover_db) will be used.

       The "-write" option will write out the merged database.  If no name is given for the new
       database, the first database read in will be overwritten.  When this option is used no
       reports are generated by default.

       Specify the "-select", "-select_re", "-ignore", and "-ignore_re" options to report on
       specific files.  "-select" and "-ignore" are interpreted as shell globs; "-select_re" and
       "-ignore_re" are interpreted as regular expressions.

       Specify "-coverage" options to report on specific criteria.  By default all available
       information on all criteria in all files will be reported.  Available coverage options are
       statement, branch, condition, subroutine, pod, and default (which equates to all available
       options).  However, if you know you only want coverage information for certain criteria it
       is better to only collect data for those criteria in the first place by specifying them at
       that point.  This will make the data collection and reporting processes faster and less
       memory intensive.  See the documentation for Devel::Cover for more information.

       If you want all *except* some criteria, then you can say something like "-coverage

       If you specify multiple "-report" options, make sure that they do not conflict.  For
       example, the different HTML reports will overwrite each other's results.

       The "-test" option will delete the databases and run your tests to generate new coverage
       data before reporting on it.  Devel::Cover knows how to work with standard Perl Makefiles
       as well as Module::Build based distributions.  For detailed instructions see the
       documentation for ExtUtils::MakeMaker at <>
       or for Module::Build at <> both of which come as
       standard in recent Perl distributions.

       The "-gcov" option will try to run gcov on any XS code.  This requires that you are using
       gcc of course.  If you are using the "-test" option will be turned on by default.

       The "-prefer_lib" option tells Devel::Cover to report on files in the lib directory even
       if they were used from the blib directory.


       The following exit values are returned:

       0   All operations were completed successfully.

       >0  An error occurred.

       With the -test option the exit status of the underlying test run is returned.




       Did I mention that this is alpha code?

       See the BUGS file.


       Copyright 2001-2018, Paul Johnson (

       This software is free.  It is licensed under the same terms as Perl itself.

       The latest version of this software should be available from my homepage: