die_on_fail of Test::Most only dies after the next test

elTriberium has asked for the wisdom of the Perl Monks concerning the following question:

Hi all, I don't know if this a bug or a feature but die_on_fail of the Test::Most CPAN module doesn't exactly do what I would expect (and want) it to do. Please have a look at this short example test:

#!/usr/bin/perl

use Test::Most tests => 3;
die_on_fail;

ok(1==2, "checkpoint 1");
lives_ok (
    sub {
        print "checkpoint 2\n";
    },
    "lives_ok test"
);
ok(1==1, "checkpoint 3");
[download]

Test 1 obviously fails, so I want it to exit the test immediately. But it still executes the subroutine of the 2nd test before exiting. Here is the program output:

-bash:perl$ perl dieonfail.pl
1..3
not ok 1 - checkpoint 1
#   Failed test 'checkpoint 1'
#   at dieonfail.pl line 6.
checkpoint 2
Test failed.  Stopping test.
# Looks like you planned 3 tests but only ran 1.
# Looks like you failed 1 test of 1 run.
# Looks like your test died just after 1.
[download]

It doesn't execute test 3, so die_on_fail is working, but it still enters the subroutine of test 2. Is there any way to keep it from running the subroutine if test 1 failed? I can of course always manually enter "|| or die" after each test, but I would prefer something automated like the "die_on_fail" option.

Comment on die_on_fail of Test::Most only dies after the next test Select or Download Code

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Re: die_on_fail of Test::Most only dies after the next test by ELISHEVA (Prior) on May 21, 2009 at 21:41 UTC
Test::Most implements `die_on_fail` by checking the result from the last run test before it runs the next. Therefore the die doesn't happen immediately. Rather it waits until your second call to `ok`. Then it dies before it runs the test. Any code between the two calls to `ok` gets executed. You can see this for yourself by looking at the source code for Test::Most (see the link on the upper left side of the page). When you open the source code page scroll down to the definition of `die_on_fail`. That function is simply a wrapper around `set_failure_handler`. `set_failure_handler` simply redefines `Test::Builder::ok` to save the result from each test and then check it the next time a test is run. Best, beth Update: fixed typo as noted below in reply, and one additional typo (s/Test::More::ok/Test::Builder::ok/).	[reply] [d/l] [select]
Re^2: die_on_fail of Test::Most only dies after the next test by elTriberium (Friar) on May 21, 2009 at 22:30 UTC
Thanks, I think you mean Test::Most instead of Test::More (die_on_fail is not defined in Test::More), but I understand what you mean. There's also a note that I can write my own failure_handler, although I'm currently not sure how to get it to die immediately. I'll play around a bit with it.	[reply]