Denis Warsow demonking

Combining two git repositories

Use case: You have repository A with remote location rA, and repository B (which may or may not have remote location rB). You want to do one of two things:

preserve all commits of both repositories, but replace everything from A with the contents of B, and use rA as your remote location
actually combine the two repositories, as if they are two branches that you want to merge, using rA as the remote location

NB: Check out git subtree/git submodule and this Stack Overflow question before going through the steps below. This gist is just a record of how I solved this problem on my own one day.

Before starting, make sure your local and remote repositories are up-to-date with all changes you need. The following steps use the general idea of changing the remote origin and renaming the local master branch of one of the repos in order to combine the two master branches.

	#!/bin/sh
	git log --shortstat \| grep -E "(Author: )(\b\s*([A-Z]\w+)){2}\|fil(e\|es) changed" \| awk '
	{
	if($1 ~ /Author/) {
	author = $2" "$3
	} else {
	files[author]+=$1
	inserted[author]+=$4
	deleted[author]+=$6
	}

	#!/usr/bin/env php
	<?php

	$name = $argv[1];
	$pfix = "\\$name";
	$len = strlen($pfix);

	require "vendor/composer/autoload_static.php";

	$tmp = get_declared_classes();

	RUN apt update
	RUN apt upgrade -y
	RUN apt install -y apt-utils
	RUN a2enmod rewrite
	RUN apt install -y libmcrypt-dev
	RUN docker-php-ext-install mcrypt
	RUN apt install -y libicu-dev
	RUN docker-php-ext-install -j$(nproc) intl
	RUN apt-get install -y libfreetype6-dev libjpeg62-turbo-dev libpng12-dev
	RUN docker-php-ext-configure gd --with-freetype-dir=/usr/include/ --with-jpeg-dir=/usr/include/

	#!/usr/bin/env python
	# -- coding: utf-8 --
	import sys
	import logging
	import getpass
	from optparse import OptionParser
	import time

	import sleekxmpp

	source "https://rubygems.org"

	gem 'eventmachine'
	gem 'sinatra'
	gem 'yajl-ruby', require: 'yajl'
	gem 'thin'
	gem 'em-websocket'

	# Backup
	docker exec CONTAINER /usr/bin/mysqldump -u root --password=root DATABASE > backup.sql

	# Restore
	cat backup.sql \| docker exec -i CONTAINER /usr/bin/mysql -u root --password=root DATABASE

	rabbitmqctl add_user test test
	rabbitmqctl set_user_tags test administrator
	rabbitmqctl set_permissions -p / test "." "." ".*"

	// Just before switching jobs:
	// Add one of these.
	// Preferably into the same commit where you do a large merge.
	//
	// This started as a tweet with a joke of "C++ pro-tip: #define private public",
	// and then it quickly escalated into more and more evil suggestions.
	// I've tried to capture interesting suggestions here.
	//
	// Contributors: @r2d2rigo, @joeldevahl, @msinilo, @_Humus_,
	// @YuriyODonnell, @rygorous, @cmuratori, @mike_acton, @grumpygiant,