I encourage wisdom seekers to present sample data and use Test::More in the example code of their question. Let's look at some examples.

How do I make the regex match?

#!/usr/bin/perl

use strict;
use warnings;
use Test::More;

my $data  = "Some string here";
my $regex = qr/ fancy regex here /mxis;

like( $data, $regex, "Matching my regex" );

done_testing;

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Your code fails, but readers can read this code and run it and make changes that will make it pass.

Why does my sub return an error?

#!/usr/bin/perl

use strict;
use warnings;
use Test::More;

sub mysub {
   return;
}

ok( mysub(), "Should return true" );

done_testing;

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Presenting larger sample data as if you were reading a file line by line.

Use __DATA__.

#!/usr/bin/perl

use strict;
use warnings;
use Test::More;

my $wanted_matches = 2;
my $actual_matches = 0;
my $regex          = qr/ fancy regex here /mxis;

while ( my $line = <DATA> ) {
   chomp $line;

   if ( $line =~ $regex ){
      $actual_matches++;
   }
}

ok( $wanted_matches == $actual_matches, "Correct number of matches" );

done_testing;

__DATA__
line one..... 
line two..... 
....
line ten.....

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Neil Watson
watson-wilson.ca

Replies are listed 'Best First'.
Re: How to ask better questions using Test::More and sample data
by haukex (Bishop) on Oct 12, 2017 at 10:31 UTC

    This post makes excellent points! Just to expand a little on regex testing - having many test cases helps:

    #!/usr/bin/env perl
use warnings;
use strict;
use Test::More;
#use re 'debug'; # optional

my $regex = qr/(foo|bar)(quz|baz)?$/;

# "match / doesn't match" tests
like   "foo",          $regex;
like   "bar",          $regex;
like   "foobar",       $regex;
like   "fooquz",       $regex;
like   "foobaz",       $regex;
like   "barbaz",       $regex;
like   "foobarquz",    $regex;
like   "foobarfooquz", $regex;
unlike "foobarquzbaz", $regex;
unlike "quzbaz",       $regex;
unlike "hello",        $regex;
unlike "foo ",         $regex;
# etc.

# check capture groups
ok "foobar"    =~ $regex;
is $1, "bar";
is $2, undef;
ok "foobarquz" =~ $regex;
is $1, "bar";
is $2, "quz";
ok "foobaz"    =~ $regex;
is $1, "foo";
is $2, "baz";
# etc.

# and/or check return values in list context
is_deeply [ "foobar" =~ $regex ],
    [ "bar", undef ];
is_deeply [ "fooquz" =~ $regex ],
    [ "foo", "quz" ];
is_deeply [ "barbaz" =~ $regex ],
    [ "bar", "baz" ];
# etc.

# an example with /g return values
is_deeply [ "foobarquzbaz" =~ /[aeiou]/g ],
    [ "o", "o", "a", "u", "a" ];
# same thing, written differently:
my @matches = "foobarquzbaz" =~ /[aeiou]/g;
is_deeply \@matches, [ "o", "o", "a", "u", "a" ];

done_testing;

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[reply]
[d/l]
Re: How to ask better questions using Test::More and sample data
by stevieb (Canon) on Feb 09, 2016 at 02:21 UTC
[reply]
[reply]

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