git-blame-summary

#!/usr/bin/env perl

#    Git Blame Summary - Show total LOC, author list, contribution percentage, and timestamp.
#    Copyright (C) 2011-2015  Richard Huang <rickypc@users.noreply.github.com>
#
#    This program is free software: you can redistribute it and/or modify
#    it under the terms of the GNU Affero General Public License as
#    published by the Free Software Foundation, either version 3 of the
#    License, or (at your option) any later version.
#
#    This program is distributed in the hope that it will be useful,
#    but WITHOUT ANY WARRANTY; without even the implied warranty of
#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#    GNU Affero General Public License for more details.
#
#    You should have received a copy of the GNU Affero General Public License
#    along with this program.  If not, see <http://www.gnu.org/licenses/>.

use Term::ANSIColor qw(:constants);
$Term::ANSIColor::AUTORESET = 1;
use warnings;
no warnings;
use strict;
use Data::Dumper;
use List::Util qw( max );

-f $ARGV[0] or die "Usage: $0 <file_to_blame>\n";

my $authors = {};
my $dates = {};

open my $fh, "git blame $ARGV[0] |" or die "Failed to run git blame: $!";

while (<$fh>) {
    my ($author) = /\w+\s+[\(](.+?)\s*\d{4}/;
    $authors->{$author}++;
    my ($date) = /(\d{4}-\d{2}-\d{2})/;
    $dates->{$author} = defined $dates->{author} ?
        ( $date > $dates->{$author} ? $date : $dates->{$author} ) : $date;
}
my $lines = $.;

close $fh;

my $date_order = {};
my $n=1;
map { $date_order->{$_} = $n++ } reverse sort { $dates->{$a} cmp $dates->{$b} }
    keys %$authors;

my ($last_author) = sort { $date_order->{$a} cmp $date_order->{$b} } keys %$authors;

print BOLD MAGENTA $ARGV[0] . " $lines lines";

if ($last_author) {
    print BOLD MAGENTA ", last touched by ";
    print BOLD RED $last_author;
    print BOLD MAGENTA " on ";
    print YELLOW $dates->{$last_author} . "\n";
}

map {
    my $percent = $authors->{$_} / $lines * 100;
    my $space = $percent < 10  ? '  ' : $percent < 100 ? ' ' : '';
    my $result = sprintf( "  %s %-02.1f %% %20s", $space, $percent, $_ );

    if ($percent > 50) {
        print BOLD RED $result;
    } elsif ($percent > 25) {
        print BOLD YELLOW $result;
    } elsif ($percent > 10) {
        print BOLD GREEN $result;
    } else {
        print BLUE $result;
    }

    my $result_date = sprintf( "   %s\n", $dates->{$_} );
    my $order = $date_order->{$_};

    if ($order == 1) {
        print RED $result_date;
    } elsif ($order < 4) {
        print YELLOW $result_date;
    } elsif ($order < 10) {
        print GREEN $result_date;
    } else {
        print MAGENTA $result_date;
    }

} sort { $authors->{$b} <=> $authors->{$a} } keys %$authors;
print "\n";

1;