Test::Harness, or a lesson about wheels not to be reinvented

Let’s say you have your unit tests in place, using something not particularly esoteric as Test::More. Good.

Now you want something to give some color to your output, so green is Good, red is Bad and you have a quicker feedback.

Time ago I wrote a quick shell script to run all the unit tests, interpret the output (in TAP format), print on screen some color output and stop the tests if something fails.

The core was:

function check_test_result() {
red='\e[0;31m'
green='\e[0;32m'
end='\033[0m'

result=`perl $1`;

echo "$result"

perl -e '{ my $input = join(" ", @ARGV); if ($input =~ /not ok/m) { exit 0; } exit 1; }' $result

if [ $? -eq 0 ]
then
echo -e "$red Not all tests passed. FAILURE$end"
exit -1
else
echo -e "$green All tests passed. SUCCESS$end"
fi
}

This works as soon as the unit tests fail (printing ‘not ok…’), but doesn’t quite work if something else is wrong (and you see the typical “your test died just after…” at the end).

Rather than improving this script, I was looking for a low hanging fruit, and eventually the easiest way I've found is to use Test::Harness prove, which BTW has color output by default.

So instead of the above (which needs also a few more lines to get the list of .t files), I can just use:

$ prove -v t/*.t

I mentioned Test::Harness prove in this post too, where I was using the JUnit module to convert from TAP to JUnit format, and get some nice code coverage report on Hudson.

Test reports on Hudson in 30 seconds (well, let's say quickly)

There are so many articles on how to generate test reports on Hudson for perl modules or applications, that I thought it was somehow complicated. It's not.

The underlying problem is that Hudson has support for test results in JUnit format. To solve this you need to convert from TAP to JUnit the test results.

Of course there are some pre-requirement:

• Your perl code must have tests (duh)
• You must have Hudson set up to run those tests
• You need to install TAP::Harness::JUnit on the building box
• You need to install 'prove' on the building box

Then all you have to do is add this command in the shell script you execute to run the tests:

prove --harness=TAP::Harness::JUnit

and configure the "Publish JUnit Test Result Reports" section of your project to point to the resulting XML file.

No mumbo jumbo.

Since TAP::Harness::JUnit is not available as a debian package, if you need to install it properly, just follow the usual procedure to generate debian packages from CPAN modules:

1. wget http://search.cpan.org/CPAN/authors/id/L/LK/LKUNDRAK/TAP-Harness-JUnit-0.32.tar.gz
2. tar -pzxvf TAP-Harness-JUnit-0.32.tar.gz
3. dh-make-perl TAP-Harness-JUnit-0.32/
4. cd TAP-Harness-JUnit-0.32
5. debuild

There you go.