In-Memory Commit Plan

1. The (Overall) Problem

There should be a lightweight way to transparently sync working copies across repositories in the background. This document covers one part of a proposed implementation.

The initial implementation's goals are:

* Enable instantaneous one-way sync of a Mercurial working directory from one machine to another. * Do not require explicit commits or pushes to make the sync happen. * Assume that network flakiness is a rare event and will not generally happen.

1.1. Why would you even want to sync working copies?

Imagine that you're working in a local repository and have local changes. At many organizations, to test your changes you would need to sync the contents over to a remote server to e.g. test by sending a small amount of production traffic.

The usual way to do that is to make an explicit commit and push, then have a hook on the server that updates the test repo to that commit.

hg commit && hg push test-server -r .

This sucks. It adds unnecessary friction to what should be a seamless process -- for a web application, if the server were running locally you would just need to save the file you're editing, run build steps (if any), then hit refresh in your browser.

This plan allows developers to get the same workflow as with local commits, except iwht

1.2. Why not just make real commits on disk and strip them when we're done?

That requires that the repository store lock be taken, and

2. The Plan