	public function AbbreviateHash($project, $hash)
	{
		if (!$project)
			return $hash;

		if (!(preg_match('/[0-9A-Fa-f]{40}/', $hash))) {
			return $hash;
		}

		$args = array();
		$args[] = '-1';
		$args[] = '--format=format:%h';
		$args[] = $hash;

		$abbrevData = explode("\n", $this->exe->Execute($project->GetPath(), GIT_REV_LIST, $args));
		if (empty($abbrevData[0])) {
			return $hash;
		}
		if (substr_compare(trim($abbrevData[0]), 'commit', 0, 6) !== 0) {
			return $hash;
		}

		if (empty($abbrevData[1])) {
			return $hash;
		}

		return trim($abbrevData[1]);
	}
The software constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command when it is sent to a downstream component.