helpers to retrieve git commmit infomation

Helpers.php

<?php
/**
 * @Author: Django Wong
 * @Date:   2017-05-03 13:00:26
 * @Last Modified by:   django-wong
 * @Last Modified time: 2017-07-06 17:01:40
 */

if(!function_exists('git_commit_hash')){
	/**
	 * current git commit hash (long)
	 * @return string
	 */
	function git_commit_hash() {
		$root = base_path();
		return trim(`cd "$root" && git rev-parse HEAD 2>&1`);
	}
}

if(!function_exists('git_commit_hash_short')){
	/**
	 * current git commit hash (short)
	 * @return string [description]
	 */
	function git_commit_hash_short() {
		$root = base_path();
		return `cd "$root" && git log --pretty=format:'%h' -n 1 2>&1`;
	}
}

if(!function_exists('git_branch_name')){
	/**
	 * current git branch name
	 * @return string 
	 */
	function git_branch_name() {
		$root = base_path();
		return `cd "$root" && git rev-parse --abbrev-ref HEAD 2>&1`;
	}
}

if(!function_exists('git_tags_on_head')){
	/**
	 * return tags on HEAD
	 * @return array<string>
	 */
	function git_tags_on_head() {
		$root = base_path();
		$result = trim(`cd "$root" && git tag --points-at HEAD 2>&1`);
		return $result ? explode("\n", $result) : [];
	}
}