[PATCH v4 7/8] gitweb: Highlight interesting parts of diff
- From
Michał Kiedrowicz <michal.kiedrowicz@gmail.com>
- Date
- Apr 11, 2012, 21:18 UTC
- Message-ID
- <1334179124-14258-8-git-send-email-michal.kiedrowicz@gmail.com>
- In-Reply-To
- <1334179124-14258-1-git-send-email-michal.kiedrowicz@gmail.com>
Reading diff output is sometimes very hard, even if it's colored, especially if lines differ only in few characters. This is often true when a commit fixes a typo or renames some variables or functions.
This commit teaches gitweb to highlight characters that are different between old and new line with a light green/red background. This should work in the similar manner as in Trac or GitHub.
The algorithm that compares lines is based on contrib/diff-highlight. Basically, it works by determining common prefix/suffix of corresponding lines and highlightning only the middle part of lines. For more information, see contrib/diff-highlight/README.
Combined diffs are not supported but a following commit will change it.
Since we need to pass esc_html()'ed or esc_html_hl_regions()'ed lines to format_diff_lines(), so it was taught to accept preformatted lines passed as a reference.
Signed-off-by: Michał Kiedrowicz <michal.kiedrowicz@gmail.com> Acked-by: Jakub Narębski <jnareb@gmail.com> --- gitweb/gitweb.perl | 107 ++++++++++++++++++++++++++++++++++++++++----- gitweb/static/gitweb.css | 8 +++ 2 files changed, 103 insertions(+), 12 deletions(-)
diff --git a/gitweb/gitweb.perl b/gitweb/gitweb.perl index 390774e..d5b3f04 100755 --- a/gitweb/gitweb.perl +++ b/gitweb/gitweb.perl @@ -2430,19 +2430,25 @@ sub format_cc_diff_chunk_header { } # process patch (diff) line (not to be used for diff headers), -# returning HTML-formatted (but not wrapped) line +# returning HTML-formatted (but not wrapped) line. +# If the line is passed as a reference, it is treated as HTML and not +# esc_html()'ed. sub format_diff_line { my ($line, $diff_class, $from, $to) = @_; - chomp $line; - $line = untabify($line); - - if ($from && $to && $line =~ m/^\@{2} /) { - $line = format_unidiff_chunk_header($line, $from, $to); - } elsif ($from && $to && $line =~ m/^\@{3}/) { - $line = format_cc_diff_chunk_header($line, $from, $to); + if (ref($line)) { + $line = $$line; } else { - $line = esc_html($line, -nbsp=>1); + chomp $line; + $line = untabify($line); + + if ($from && $to && $line =~ m/^\@{2} /) { + $line = format_unidiff_chunk_header($line, $from, $to); + } elsif ($from && $to && $line =~ m/^\@{3}/) { + $line = format_cc_diff_chunk_header($line, $from, $to); + } else { + $line = esc_html($line, -nbsp=>1); + } } my $diff_classes = "diff"; @@ -5055,10 +5061,89 @@ sub print_inline_diff_lines { print @$ctx, @$rem, @$add; } +# Format removed and added line, mark changed part and HTML-format them. +# Implementation is based on contrib/diff-highlight +sub format_rem_add_lines_pair { + my ($rem, $add) = @_; + + # We need to untabify lines before split()'ing them; + # otherwise offsets would be invalid. + chomp $rem; + chomp $add; + $rem = untabify($rem); + $add = untabify($add); + + my @rem = split(//, $rem); + my @add = split(//, $add); + my ($esc_rem, $esc_add); + # Ignore +/- character, thus $prefix_len is set to 1. + my ($prefix_len, $suffix_len) = (1, 0); + my ($prefix_has_nonspace, $suffix_has_nonspace); + + my $shorter = (@rem < @add) ? @rem : @add; + while ($prefix_len < $shorter) { + last if ($rem[$prefix_len] ne $add[$prefix_len]); + + $prefix_has_nonspace = 1 if ($rem[$prefix_len] !~ /\s/); + $prefix_len++; + } + + while ($prefix_len + $suffix_len < $shorter) { + last if ($rem[-1 - $suffix_len] ne $add[-1 - $suffix_len]); + + $suffix_has_nonspace = 1 if ($rem[-1 - $suffix_len] !~ /\s/); + $suffix_len++; + } + + # Mark lines that are different from each other, but have some common + # part that isn't whitespace. If lines are completely different, don't + # mark them because that would make output unreadable, especially if + # diff consists of multiple lines. + if ($prefix_has_nonspace || $suffix_has_nonspace) { + $esc_rem = esc_html_hl_regions($rem, 'marked', + [$prefix_len, @rem - $suffix_len], -nbsp=>1); + $esc_add = esc_html_hl_regions($add, 'marked', + [$prefix_len, @add - $suffix_len], -nbsp=>1); + } else { + $esc_rem = esc_html($rem, -nbsp=>1); + $esc_add = esc_html($add, -nbsp=>1); + } + + return format_diff_line(\$esc_rem, 'rem'), + format_diff_line(\$esc_add, 'add'); +} + +# HTML-format diff context, removed and added lines. +sub format_ctx_rem_add_lines { + my ($ctx, $rem, $add, $is_combined) = @_; + my (@new_ctx, @new_rem, @new_add); + + # Highlight if every removed line has a corresponding added line. + # Combined diffs are not supported at this moment. + if (!$is_combined && @$add > 0 && @$add == @$rem) { + for (my $i = 0; $i < @$add; $i++) { + my ($line_rem, $line_add) = format_rem_add_lines_pair( + $rem->[$i], $add->[$i]); + push @new_rem, $line_rem; + push @new_add, $line_add; + } + } else { + @new_rem = map { format_diff_line($_, 'rem') } @$rem; + @new_add = map { format_diff_line($_, 'add') } @$add; + } + + @new_ctx = map { format_diff_line($_, 'ctx') } @$ctx; + + return (\@new_ctx, \@new_rem, \@new_add); +} + # Print context lines and then rem/add lines. sub print_diff_lines { my ($ctx, $rem, $add, $diff_style, $is_combined) = @_; + ($ctx, $rem, $add) = format_ctx_rem_add_lines($ctx, $rem, $add, + $is_combined); + if ($diff_style eq 'sidebyside' && !$is_combined) { print_sidebyside_diff_lines($ctx, $rem, $add); } else { @@ -5090,11 +5175,9 @@ sub print_diff_chunk { foreach my $line_info (@chunk) { my ($class, $line) = @$line_info; - $line = format_diff_line($line, $class, $from, $to); - # print chunk headers if ($class && $class eq 'chunk_header') { - print $line; + print format_diff_line($line, $class, $from, $to); next; } diff --git a/gitweb/static/gitweb.css b/gitweb/static/gitweb.css index c530355..cb86d2d 100644 --- a/gitweb/static/gitweb.css +++ b/gitweb/static/gitweb.css @@ -438,6 +438,10 @@ div.diff.add { color: #008800; } +div.diff.add span.marked { + background-color: #aaffaa; +} + div.diff.from_file a.path, div.diff.from_file { color: #aa0000; @@ -447,6 +451,10 @@ div.diff.rem { color: #cc0000; } +div.diff.rem span.marked { + background-color: #ffaaaa; +} + div.diff.chunk_header a, div.diff.chunk_header { color: #990099;
-- 1.7.8.4