Like this

#!/usr/bin/perl --

use strict;
use warnings;

use Test::More qw' no_plan ';

Main( @ARGV );
exit( 0 );

sub Main {
    Happy(\&pichi_nakodadaka, 'pichi_nakodadaka' );
    Happy(\&pichi_nakodadaka2, 'pichi_nakodadaka2' );
}

sub Happy {
    my( $ref, $name ) = @_;
    my @arg = (
[ '#include "string.h"', 'string.h' ],
[ '#include <stdlib.h>', 'stdlib.h' ],
[ '#include <sys/dispatch.h>', 'dispatch.h' ],
    );

    for my $arg( @arg ){
        my( $in, $expect ) = @$arg;
        my $got = $ref->($in);
        is($got, $expect , $name);
    }
}

sub pichi_nakodadaka {
    my( $in ) = @_;
    return $1 if $in =~ /#include [<"](\S+\.h)[>"]/ ;
}

sub pichi_nakodadaka2 {
    my( $in ) = @_;
    if( $in =~ /#include [<"](\S+\.h)[>"]/ ){
        my $pichi_nakodadaka = $1;
        $pichi_nakodadaka =~ s!^.*?/!!g;
        return $pichi_nakodadaka;
    }
}

__END__
$ perl pm.894302.pl
ok 1 - pichi_nakodadaka
ok 2 - pichi_nakodadaka
not ok 3 - pichi_nakodadaka
#   Failed test 'pichi_nakodadaka'
#   at pm.894302.pl line 33.
#          got: 'sys/dispatch.h'
#     expected: 'dispatch.h'
ok 4 - pichi_nakodadaka2
ok 5 - pichi_nakodadaka2
ok 6 - pichi_nakodadaka2
1..6
# Looks like you failed 1 test of 6.
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