Generating build number from git branch name and commit count.

build_number_gen.php

<?php
/**
 * Generate a build number based on Git commit count and current branch.
 * @return string Format: "{$branch}.{$commitCount}"
 */
public function buildNumber()
{
	$branch = exec('git rev-parse --abbrev-ref HEAD');
	$commitCount = exec('git rev-list HEAD --count');

	return "{$branch}.{$commitCount}";
}