view release on metacpan or  search on metacpan

cdiff.pl  view on Meta::CPAN

    # At first, a hunk will have just one Block in it
    my $hunk = {
	    "start1" => $start1,
	    "start2" => $start2,
	    "end1" => $end1,
	    "end2" => $end2,
	    "blocks" => [$block],
              };
    bless $hunk, $class;

    $hunk->flag_context($context_items);

    return $hunk;
}

# Change the "start" and "end" fields to note that context should be added
# to this hunk
sub flag_context {
    my ($hunk, $context_items) = @_;
    return unless $context_items; # no context

    # add context before
    my $start1 = $hunk->{"start1"};
    my $num_added = $context_items > $start1 ? $start1 : $context_items;
    $hunk->{"start1"} -= $num_added;
    $hunk->{"start2"} -= $num_added;

    # context after
    my $end1 = $hunk->{"end1"};
    $num_added = ($end1+$context_items > $#f1) ?
                  $#f1 - $end1 :
                  $context_items;
    $hunk->{"end1"} += $num_added;
    $hunk->{"end2"} += $num_added;
}

# Is there an overlap between hunk arg0 and old hunk arg1?
# Note: if end of old hunk is one less than beginning of second, they overlap
sub does_overlap {
    my ($hunk, $oldhunk) = @_;
    return "" unless $oldhunk; # first time through, $oldhunk is empty

    # Do I actually need to test both?
    return ($hunk->{"start1"} - $oldhunk->{"end1"} <= 1 ||
            $hunk->{"start2"} - $oldhunk->{"end2"} <= 1);
}

# Prepend hunk arg1 to hunk arg0
# Note that arg1 isn't updated! Only arg0 is.
sub prepend_hunk {
    my ($hunk, $oldhunk) = @_;

    $hunk->{"start1"} = $oldhunk->{"start1"};
    $hunk->{"start2"} = $oldhunk->{"start2"};

    unshift (@{$hunk->{"blocks"}}, @{$oldhunk->{"blocks"}});
}


# DIFF OUTPUT ROUTINES. THESE ROUTINES CONTAIN DIFF FORMATTING INFO...
sub output_diff {
    if    (defined $main::opt_u) {&output_unified_diff(@_)}
    elsif (defined $main::opt_c) {&output_context_diff(@_)}
    else {die "unknown diff"}
}

sub output_unified_diff {
    my ($hunk, $fileref1, $fileref2) = @_;
    my @blocklist;

    # Calculate item number range.
    my $range1 = $hunk->unified_range(1);
    my $range2 = $hunk->unified_range(2);
    print "@@ -$range1 +$range2 @@\n";

    # Outlist starts containing the hunk of file 1.
    # Removing an item just means putting a '-' in front of it.
    # Inserting an item requires getting it from file2 and splicing it in.
    #    We splice in $num_added items. Remove blocks use $num_added because
    # splicing changed the length of outlist.
    #    We remove $num_removed items. Insert blocks use $num_removed because
    # their item numbers---corresponding to positions in file *2*--- don't take
    # removed items into account.
    my $low = $hunk->{"start1"};
    my $hi = $hunk->{"end1"};
    my ($num_added, $num_removed) = (0,0);
    my @outlist = @$fileref1[$low..$hi];
    map {s/^/ /} @outlist; # assume it's just context

    foreach my $block (@{$hunk->{"blocks"}}) {
	foreach my $item ($block->remove) {
	    my $op = $item->{"sign"}; # -
	    my $offset = $item->{"item_no"} - $low + $num_added;
	    $outlist[$offset] =~ s/^ /$op/;
	    $num_removed++;
	}
	foreach my $item ($block->insert) {
	    my $op = $item->{"sign"}; # +
	    my $i = $item->{"item_no"};
	    my $offset = $i - $hunk->{"start2"} + $num_removed;
	    splice(@outlist,$offset,0,"$op$$fileref2[$i]");
	    $num_added++;
	}
    }

    map {s/$/\n/} @outlist; # add \n's
    print @outlist;

}

sub output_context_diff {
    my ($hunk, $fileref1, $fileref2) = @_;
    my @blocklist;

    print "***************\n";
    # Calculate item number range.
    my $range1 = $hunk->context_range(1);
    my $range2 = $hunk->context_range(2);

    # Print out file 1 part for each block in context diff format if there are