It's not immediately obvious how to pull down the code for a PR and test it locally. But it's pretty easy. (This assumes you have a remote for the main repo named upstream.)

Getting the PR code

1. Make note of the PR number. For example, Rod's latest is PR #37: Psiphon-Labs/psiphon-tunnel-core#37

2. Fetch the PR's pseudo-branch (or bookmark or rev pointer whatever the word is), and give it a local branch name. Here we'll name it pr37:

$ git fetch upstream pull/37/head:pr37

Open ~/.bash_profile in your favorite editor and add the following content to the bottom.

# Git branch in prompt.

parse_git_branch() {