diff --git a/contrib/diff-highlight/diff-highlight b/contrib/diff-highlight/diff-highlight index c3302dd817..0d8df84a20 100755 --- a/contrib/diff-highlight/diff-highlight +++ b/contrib/diff-highlight/diff-highlight @@ -8,6 +8,7 @@ use strict; my $HIGHLIGHT = "\x1b[7m"; my $UNHIGHLIGHT = "\x1b[27m"; my $COLOR = qr/\x1b\[[0-9;]*m/; +my $BORING = qr/$COLOR|\s/; my @window; @@ -104,8 +105,14 @@ sub show_pair { } } - print highlight(\@a, $pa, $sa); - print highlight(\@b, $pb, $sb); + if (is_pair_interesting(\@a, $pa, $sa, \@b, $pb, $sb)) { + print highlight(\@a, $pa, $sa); + print highlight(\@b, $pb, $sb); + } + else { + print join('', @a); + print join('', @b); + } } sub split_line { @@ -125,3 +132,20 @@ sub highlight { @{$line}[($suffix+1)..$#$line] ); } + +# Pairs are interesting to highlight only if we are going to end up +# highlighting a subset (i.e., not the whole line). Otherwise, the highlighting +# is just useless noise. We can detect this by finding either a matching prefix +# or suffix (disregarding boring bits like whitespace and colorization). +sub is_pair_interesting { + my ($a, $pa, $sa, $b, $pb, $sb) = @_; + my $prefix_a = join('', @$a[0..($pa-1)]); + my $prefix_b = join('', @$b[0..($pb-1)]); + my $suffix_a = join('', @$a[($sa+1)..$#$a]); + my $suffix_b = join('', @$b[($sb+1)..$#$b]); + + return $prefix_a !~ /^$COLOR*-$BORING*$/ || + $prefix_b !~ /^$COLOR*\+$BORING*$/ || + $suffix_a !~ /^$BORING*$/ || + $suffix_b !~ /^$BORING*$/; +}