Using externally generated TAP to drive a test

[creamygoodness]

Let's say I've got a string containing some TAP output:

1..4
ok 1
ok 2
not ok 3
#   Failed test at t/my_test.t line 7.
ok 4

In real life, the source for the TAP output is a compiled C app that generates TAP, but we can simulate it using a plain old string for demo purposes. I can feed the $tap string to a TAP::Parser object:

my $tap = qx|./compiled_test_app|;
my $parser = TAP::Parser->new( { tap => $tap } );

The goal is to wrap the compiled test app with a Perl script and run it as part of a test suite. I've been able to get the TAP::Parser object to iterate over the lines in the TAP string. However, I haven't been able to figure out how to extract clean test results.

Here's a coarse attempt:

use strict;
use warnings;

use Test::More;
use TAP::Parser;

my $tap = <<'END_TAP';
1..4
ok 1
ok 2
not ok 3
#   Failed test at t/my_test.t line 7.
ok 4
END_TAP

my $parser = TAP::Parser->new( { tap => $tap } );

my $plan = $parser->next;
die "not a plan" unless $plan->is_plan;
plan( tests => $plan->tests_planned );

while ( my $result = $parser->next ) {
    if ( $result->is_test ) {
        if ( $result->is_ok ) {
            pass( $result->as_string );
        }
        else {
            fail( $result->as_string );
        }
    }
    elsif ( $result->is_comment ) {
        print $result->as_string;
    }
    else {
        die "Can't figure out what to do with $result";
    }
}

... and here's the garbled output it produces:

1..4
ok 1 - ok 1
ok 2 - ok 2
not ok 3 - not ok 3
#   Failed test 'not ok 3'
#   at t/tap_wrapper.t line 28.
#   Failed test at t/my_test.t line 7.ok 4 - ok 4
# Looks like you failed 1 test of 4.

Is this something that I should be able to use TAP::Parser for, or am I barking up the wrong tree? I actually feel like the result-by-result approach of that test script is completely wrong -- I'd need to add more cases for TODO tests, SKIP directives, etc. The script really ought to look something like this:

use Test::ParseTAP;
my $tap = qx|./compiled_test|;
parse_tap($tap);

Suggestions?

[jasonk]

Maybe I'm missing something, but if you are just trying to write a perl test script to produce TAP output from your binary which already produces TAP output, why not just...

#!/usr/bin/perl -w
qx|./compiled_test_app|;

and then deal with it the same way you deal with your other test scripts, using prove or something like it, instead of trying to interpret the TAP just to produce more TAP output...

[creamygoodness]

Heh. It really is that simple! Somehow I'd figured there had to be more to it than just printing test output.

Thanks!

[moritz]

Maybe this example of how to run tests and get the results is helpful for you. It requires a relative new TAP::Harness (3.0 iirc).

Update: I'm not sure if this counts as "externally generated", I'll have a closer look tomorrow.