use strict; use warnings; use feature 'say';
use Path::Tiny;

my %file_map = ( tag1 => Path::Tiny->tempfile, tag2 => Path::Tiny->tempfile );

chomp( my @lines  = <DATA> );

for ( @lines ) {
    my ( $txt, $tag ) = split / : /;
    path( $file_map{ $tag } )->append("$txt\n");
}

for ( keys %file_map ) {
    say $file_map{ $_ };
    say $file_map{ $_ }->slurp;
}

__END__
test/foo/bar : tag1
test/abc/xyz : tag1
test/def/abc : tag2
test/bar/foo : tag2
test/dummy/foo : tag1

##</code><code>##

perl 1206430.pl

/tmp/k6iEPAjgjR
test/def/abc
test/bar/foo

/tmp/aFliecLlJN
test/foo/bar
test/abc/xyz
test/dummy/foo