use 5.014;
use warnings;

package Temp;
use parent 'File::Temp';

sub new { 
    my $self = shift;
    $self-> SUPER::new( DIR => '.' )
}

sub DESTROY {
    my $self = shift;
    say 'global' if ${^GLOBAL_PHASE} eq 'DESTRUCT';
    $self-> SUPER::DESTROY
}

package main;
use File::Copy;

sub foo { my $h = Temp-> new }

die unless -f 'x';      # this file must exist

copy 'x', my $fn1 = Temp-> new-> filename                or die;
copy 'x', my $fn2 = do { Temp-> new }-> filename         or die;
copy 'x', my $fn3 = do { my $h = Temp-> new }-> filename or die;
copy 'x', my $fn4 = foo-> filename                       or die;

say 1 if -f $fn1;
say 2 if -f $fn2;
say 3 if -f $fn3;
say 4 if -f $fn4;