package TestCompare;
use vars qw(@ISA @EXPORT $MYPKG);
#use strict;
#use diagnostics;
use Carp;
use Exporter;
use File::Basename;
use File::Spec;
use FileHandle;
@ISA = qw(Exporter);
@EXPORT = qw(&testcmp);
$MYPKG = eval { (caller)[0] };
##--------------------------------------------------------------------------
=head1 NAME
testcmp -- compare two files line-by-line
=head1 SYNOPSIS
$is_diff = testcmp($file1, $file2);
or
$is_diff = testcmp({-cmplines => \&mycmp}, $file1, $file2);
=head2 DESCRIPTION
Compare two text files line-by-line and return 0 if they are the
same, 1 if they differ. Each of $file1 and $file2 may be a filenames,
or a filehandles (in which case it must already be open for reading).
If the first argument is a hashref, then the B<-cmplines> key in the
hash may have a subroutine reference as its corresponding value.
The referenced user-defined subroutine should be a line-comparator
function that takes two pre-chomped text-lines as its arguments
(the first is from $file1 and the second is from $file2). It should
return 0 if it considers the two lines equivalent, and non-zero
otherwise.
=cut
##--------------------------------------------------------------------------
sub testcmp( $ $ ; $) {
my %opts = ref($_[0]) eq 'HASH' ? %{shift()} : ();
my ($file1, $file2) = @_;
my ($fh1, $fh2) = ($file1, $file2);
unless (ref $fh1) {
$fh1 = FileHandle->new($file1, "r") or die "Can't open $file1: $!";
}
unless (ref $fh2) {
$fh2 = FileHandle->new($file2, "r") or die "Can't open $file2: $!";
}
my $cmplines = $opts{'-cmplines'} || undef;
my ($f1text, $f2text) = ("", "");
my ($line, $diffs) = (0, 0);
while ( defined($f1text) and defined($f2text) ) {
defined($f1text = <$fh1>) and chomp($f1text);
defined($f2text = <$fh2>) and chomp($f2text);
++$line;
last unless ( defined($f1text) and defined($f2text) );
$diffs = (ref $cmplines) ? &$cmplines($f1text, $f2text)
: ($f1text ne $f2text);
last if $diffs;
}
close($fh1) unless (ref $file1);
close($fh2) unless (ref $file2);
$diffs = 1 if (defined($f1text) or defined($f2text));
if ( defined($f1text) and defined($f2text) ) {
## these two lines must be different
warn "$file1 and $file2 differ at line $line\n";
}
elsif (defined($f1text) and (! defined($f1text))) {
## file1 must be shorter
warn "$file1 is shorter than $file2\n";
}
elsif (defined $f2text) {
## file2 must be longer
warn "$file1 is shorter than $file2\n";
}
return $diffs;
}
1;