Section: Perl Programmers Reference Guide (3pm)
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Test::Harness - Run Perl standard test scripts with statistics
STOP! If all you want to do is write a test script, consider
using Test::Simple. Test::Harness is the module that reads the
output from Test::Simple, Test::More and other modules based on
Test::Builder. You don't need to know about Test::Harness to use
Test::Harness runs tests and expects output from the test in a
certain format. That format is called TAP, the Test Anything
Protocol. It is defined in Test::Harness::TAP.
"Test::Harness::runtests(@tests)" runs all the testscripts named
as arguments and checks standard output for the expected strings
in TAP format.
The prove utility is a thin wrapper around Test::Harness.
Test::Harness will honor the "-T" or "-t" in the #! line on your
test files. So if you begin a test with:
the test will be run with taint mode on.
These variables can be used to configure the behavior of
Test::Harness. They are exported on request.
The package variable $Test::Harness::Verbose is exportable and can be
used to let "runtests()" display the standard output of the script
without altering the behavior otherwise. The prove utility's "-v"
flag will set this.
The package variable $Test::Harness::switches is exportable and can be
used to set perl command line options used for running the test
script(s). The default value is "-w". It overrides "HARNESS_SWITCHES".
If set to true, and "Time::HiRes" is available, print elapsed seconds
after each test file.
When tests fail, analyze the summary report:
Test returned status 3 (wstat 768, 0x300)
DIED. FAILED tests 1, 3, 5, 7, 9, 11, 13, 15, 17, 19
Failed 10/20 tests, 50.00% okay
Failed Test Stat Wstat Total Fail Failed List of Failed
t/waterloo.t 3 768 20 10 50.00% 1 3 5 7 9 11 13 15 17 19
Failed 1/5 test scripts, 80.00% okay. 10/44 subtests failed, 77.27% okay.
Everything passed but t/waterloo.t. It failed 10 of 20 tests and
exited with non-zero status indicating something dubious happened.
The columns in the summary report mean:
- Failed Test
The test file which failed.
If the test exited with non-zero, this is its exit status.
The wait status of the test.
Total number of tests expected to run.
Number which failed, either from ``not ok'' or because they never ran.
Percentage of the total tests which failed.
- List of Failed
A list of the tests which failed. Successive failures may be
abbreviated (ie. 15-20 to indicate that tests 15, 16, 17, 18, 19 and
Test::Harness currently only has one function, here it is.
my $allok = runtests(@test_files);
This runs all the given @test_files and divines whether they passed
or failed based on their output to STDOUT (details above). It prints
out each individual test which failed along with a summary report and
a how long it all took.
It returns true if everything was ok. Otherwise it will "die()" with
one of the messages in the DIAGNOSTICS section.
&runtests is exported by Test::Harness by default.
$verbose, $switches and $debug are exported upon request.
- All tests successful.\nFiles=%d, Tests=%d, %s
If all tests are successful some statistics about the performance are
- FAILED tests %s\n\tFailed %d/%d tests, %.2f%% okay.
For any single script that has failing subtests statistics like the
above are printed.
- Test returned status %d (wstat %d)
Scripts that return a non-zero exit status, both "$? >> 8"
and $? are printed in a message similar to the above.
- Failed 1 test, %.2f%% okay. %s
- Failed %d/%d tests, %.2f%% okay. %s
If not all tests were successful, the script dies with one of the
- FAILED--Further testing stopped: %s
If a single subtest decides that further testing will not make sense,
the script dies with this message.
ENVIRONMENT VARIABLES THAT TEST::HARNESS SETS
Test::Harness sets these before executing the individual tests.
This is set to a true value. It allows the tests to determine if they
are being executed through the harness or by any other means.
This is the version of Test::Harness.
ENVIRONMENT VARIABLES THAT AFFECT TEST::HARNESS
This value will be used for the width of the terminal. If it is not
set then it will default to "COLUMNS". If this is not set, it will
default to 80. Note that users of Bourne-sh based shells will need to
"export COLUMNS" for this module to use that variable.
When true it will make harness attempt to compile the test using
"perlcc" before running it.
NOTE This currently only works when sitting in the perl source
If true, Test::Harness will print debugging information about itself as
it runs the tests. This is different from "HARNESS_VERBOSE", which prints
the output from the test being run. Setting $Test::Harness::Debug will
override this, or you can use the "-d" switch in the prove utility.
When set to the name of a directory, harness will check after each
test whether new files appeared in that directory, and report them as
LEAKED FILES: scr.tmp 0 my.db
If relative, directory name is with respect to the current directory at
the moment runtests() was called. Putting absolute path into
"HARNESS_FILELEAK_IN_DIR" may give more predictable results.
Makes harness ignore the exit status of child processes when defined.
When set to a true value, forces it to behave as though STDOUT were
not a console. You may need to set this if you don't want harness to
output more frequent progress messages using carriage returns. Some
consoles may not handle carriage returns properly (which results in a
somewhat messy output).
Usually your tests will be run by $^X, the currently-executing Perl.
However, you may want to have it run by a different executable, such as
a threading perl, or a different version.
If you're using the prove utility, you can use the "--perl" switch.
Its value will be prepended to the switches used to invoke perl on
each test. For example, setting "HARNESS_PERL_SWITCHES" to "-W" will
run all tests with all warnings enabled.
If true, Test::Harness will output the verbose results of running
its tests. Setting $Test::Harness::verbose will override this,
or you can use the "-v" switch in the prove utility.
Here's how Test::Harness tests itself
$ cd ~/src/devel/Test-Harness
$ perl -Mblib -e 'use Test::Harness qw(&runtests $verbose);
$verbose=0; runtests @ARGV;' t/*.t
All tests successful.
Files=4, Tests=24, 2 wallclock secs ( 0.61 cusr + 0.41 csys = 1.02 CPU)
The included prove utility for running test scripts from the command line,
Test and Test::Simple for writing test scripts, Benchmark for
the underlying timing routines, and Devel::Cover for test coverage
Provide a way of running tests quietly (ie. no printing) for automated
validation of tests. This will probably take the form of a version
of runtests() which rather than printing its output returns raw data
on the state of the tests. (Partially done in Test::Harness::Straps)
Document the format.
Fix HARNESS_COMPILE_TEST without breaking its core usage.
Figure a way to report test names in the failure summary.
Rework the test summary so long test names are not truncated as badly.
(Partially done with new skip test styles)
Add option for coverage analysis.
Implement Straps total_results()
Remember exit code
Completely redo the print summary code.
Implement Straps callbacks. (experimentally implemented)
Straps->analyze_file() not taint clean, don't know if it can be
Fix that damned VMS nit.
HARNESS_TODOFAIL to display TODO failures
Add a test for verbose.
Change internal list of test results to a hash.
Fix stats display when there's an overrun.
Fix so perls with spaces in the filename work.
Keeping whittling away at _run_all_tests()
Clean up how the summary is printed. Get rid of those damned formats.
HARNESS_COMPILE_TEST currently assumes it's run from the Perl source
Please use the CPAN bug ticketing system at <http://rt.cpan.org/>.
You can also mail bugs, fixes and enhancements to
"<bug-test-harness" at "rt.cpan.org>".
Either Tim Bunce or Andreas Koenig, we don't know. What we know for
sure is, that it was inspired by Larry Wall's TEST script that came
with perl distributions for ages. Numerous anonymous contributors
exist. Andreas Koenig held the torch for many years, and then
Michael G Schwern.
Current maintainer is Andy Lester "<andy at petdance.com>".
by Michael G Schwern "<schwern at pobox.com>",
Andy Lester "<andy at petdance.com>".
This program is free software; you can redistribute it and/or
modify it under the same terms as Perl itself.
- Taint mode
- Configuration variables.
- ENVIRONMENT VARIABLES THAT TEST::HARNESS SETS
- ENVIRONMENT VARIABLES THAT AFFECT TEST::HARNESS
- SEE ALSO
linux.jgfs.net manual pages