extract two git commit hashes out of the pasteboard and do a git diff on them

git-diff-paste

#!/usr/bin/perl
 
# extract two git commit hashes out of the pasteboard and do a git diff on them.
# 
# no need to clean up any extra stuff in the paste -- this will do a diff of the
# top-most and bottom-most hashes found in the paste.
#
# requires pbpaste command line utility

use strict;
use warnings;

my $data = `pbpaste`;

my @data = split(/[\n\r]+/, $data);

my ($top,$bot);
foreach my $line (@data) {
    if ($line =~ /commit ([a-f0-9]{40})/) {
        my $match = $1;
        if (!defined($top)) {
            $top = $match;
        }
        else {
            $bot = $match;
        }
    }
}

die "usage: $0" .
    "\n\nMust have data on pasteboard to use this.\n\n" .
    "Pasteboard should include at least two git hashes.\n\n" .
    "Diff will be done of two most distant hashes.\n\n"
    unless (defined($top) && defined($bot));

print "diff of $bot and $top:\n\n";
print `git diff $bot $top`;