Merge branch 'dev' of github.com:typebrook/settings into dev

2 files changed, 214 insertions, 1 deletions

diff --git a/tools/diff-highlight b/tools/diff-highlight
new file mode 100755
index 0000000..08c88bb
--- /dev/null
+++ b/tools/diff-highlight
@@ -0,0 +1,213 @@
+#!/usr/bin/perl
+
+use warnings FATAL => 'all';
+use strict;
+
+# Highlight by reversing foreground and background. You could do
+# other things like bold or underline if you prefer.
+my @OLD_HIGHLIGHT = (
+        color_config('color.diff-highlight.oldnormal'),
+        color_config('color.diff-highlight.oldhighlight', "\x1b[7m"),
+        color_config('color.diff-highlight.oldreset', "\x1b[27m")
+);
+my @NEW_HIGHLIGHT = (
+        color_config('color.diff-highlight.newnormal', $OLD_HIGHLIGHT[0]),
+        color_config('color.diff-highlight.newhighlight', $OLD_HIGHLIGHT[1]),
+        color_config('color.diff-highlight.newreset', $OLD_HIGHLIGHT[2])
+);
+
+my $RESET = "\x1b[m";
+my $COLOR = qr/\x1b\[[0-9;]*m/;
+my $BORING = qr/$COLOR|\s/;
+
+my @removed;
+my @added;
+my $in_hunk;
+
+# Some scripts may not realize that SIGPIPE is being ignored when launching the
+# pager--for instance scripts written in Python.
+$SIG{PIPE} = 'DEFAULT';
+
+while (<>) {
+        if (!$in_hunk) {
+                print;
+                $in_hunk = /^$COLOR*\@/;
+        }
+        elsif (/^$COLOR*-/) {
+                push @removed, $_;
+        }
+        elsif (/^$COLOR*\+/) {
+                push @added, $_;
+        }
+        else {
+                show_hunk(\@removed, \@added);
+                @removed = ();
+                @added = ();
+
+                print;
+                $in_hunk = /^$COLOR*[\@ ]/;
+        }
+
+        # Most of the time there is enough output to keep things streaming,
+        # but for something like "git log -Sfoo", you can get one early
+        # commit and then many seconds of nothing. We want to show
+        # that one commit as soon as possible.
+        #
+        # Since we can receive arbitrary input, there's no optimal
+        # place to flush. Flushing on a blank line is a heuristic that
+        # happens to match git-log output.
+        if (!length) {
+                local $| = 1;
+        }
+}
+
+# Flush any queued hunk (this can happen when there is no trailing context in
+# the final diff of the input).
+show_hunk(\@removed, \@added);
+
+exit 0;
+
+# Ideally we would feed the default as a human-readable color to
+# git-config as the fallback value. But diff-highlight does
+# not otherwise depend on git at all, and there are reports
+# of it being used in other settings. Let's handle our own
+# fallback, which means we will work even if git can't be run.
+sub color_config {
+        my ($key, $default) = @_;
+        my $s = `git config --get-color $key 2>/dev/null`;
+        return length($s) ? $s : $default;
+}
+
+sub show_hunk {
+        my ($a, $b) = @_;
+
+        # If one side is empty, then there is nothing to compare or highlight.
+        if (!@$a || !@$b) {
+                print @$a, @$b;
+                return;
+        }
+
+        # If we have mismatched numbers of lines on each side, we could try to
+        # be clever and match up similar lines. But for now we are simple and
+        # stupid, and only handle multi-line hunks that remove and add the same
+        # number of lines.
+        if (@$a != @$b) {
+                print @$a, @$b;
+                return;
+        }
+
+        my @queue;
+        for (my $i = 0; $i < @$a; $i++) {
+                my ($rm, $add) = highlight_pair($a->[$i], $b->[$i]);
+                print $rm;
+                push @queue, $add;
+        }
+        print @queue;
+}
+
+sub highlight_pair {
+        my @a = split_line(shift);
+        my @b = split_line(shift);
+
+        # Find common prefix, taking care to skip any ansi
+        # color codes.
+        my $seen_plusminus;
+        my ($pa, $pb) = (0, 0);
+        while ($pa < @a && $pb < @b) {
+                if ($a[$pa] =~ /$COLOR/) {
+                        $pa++;
+                }
+                elsif ($b[$pb] =~ /$COLOR/) {
+                        $pb++;
+                }
+                elsif ($a[$pa] eq $b[$pb]) {
+                        $pa++;
+                        $pb++;
+                }
+                elsif (!$seen_plusminus && $a[$pa] eq '-' && $b[$pb] eq '+') {
+                        $seen_plusminus = 1;
+                        $pa++;
+                        $pb++;
+                }
+                else {
+                        last;
+                }
+        }
+
+        # Find common suffix, ignoring colors.
+        my ($sa, $sb) = ($#a, $#b);
+        while ($sa >= $pa && $sb >= $pb) {
+                if ($a[$sa] =~ /$COLOR/) {
+                        $sa--;
+                }
+                elsif ($b[$sb] =~ /$COLOR/) {
+                        $sb--;
+                }
+                elsif ($a[$sa] eq $b[$sb]) {
+                        $sa--;
+                        $sb--;
+                }
+                else {
+                        last;
+                }
+        }
+
+        if (is_pair_interesting(\@a, $pa, $sa, \@b, $pb, $sb)) {
+                return highlight_line(\@a, $pa, $sa, \@OLD_HIGHLIGHT),
+                       highlight_line(\@b, $pb, $sb, \@NEW_HIGHLIGHT);
+        }
+        else {
+                return join('', @a),
+                       join('', @b);
+        }
+}
+
+sub split_line {
+        local $_ = shift;
+        return map { /$COLOR/ ? $_ : (split //) }
+               split /($COLOR*)/;
+}
+
+sub highlight_line {
+        my ($line, $prefix, $suffix, $theme) = @_;
+
+        my $start = join('', @{$line}[0..($prefix-1)]);
+        my $mid = join('', @{$line}[$prefix..$suffix]);
+        my $end = join('', @{$line}[($suffix+1)..$#$line]);
+
+        # If we have a "normal" color specified, then take over the whole line.
+        # Otherwise, we try to just manipulate the highlighted bits.
+        if (defined $theme->[0]) {
+                s/$COLOR//g for ($start, $mid, $end);
+                chomp $end;
+                return join('',
+                        $theme->[0], $start, $RESET,
+                        $theme->[1], $mid, $RESET,
+                        $theme->[0], $end, $RESET,
+                        "\n"
+                );
+        } else {
+                return join('',
+                        $start,
+                        $theme->[1], $mid, $theme->[2],
+                        $end
+                );
+        }
+}
+
+# Pairs are interesting to highlight only if we are going to end up
+# highlighting a subset (i.e., not the whole line). Otherwise, the highlighting
+# is just useless noise. We can detect this by finding either a matching prefix
+# or suffix (disregarding boring bits like whitespace and colorization).
+sub is_pair_interesting {
+        my ($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*$/;
+}
diff --git a/tools/install.sh b/tools/install.sh
index f16b2dd..0b59e28 100755
--- a/tools/install.sh
+++ b/tools/install.sh
@@ -16,7 +16,7 @@ if [ ! -d $SETTING_DIR ]; then
   }
 fi
 
-sed -i "\^# $REPO^, /^$/ d"  $RCFILE
+sed -i "\^# $REPO^, /^$/ d" $RCFILE
 echo "
 # $REPO
 export SETTING_DIR=$SETTING_DIR