/**
* Registers a path alias.
*
* A path alias is a short name representing a long path (a file path, a URL, etc.)
* For example, we use '@rock' as the alias of the path to the Rock framework directory.
*
* A path alias must start with the character '@' so that it can be easily differentiated
* from non-alias paths.
*
* Note that this method does not check if the given path exists or not. All it does is
* to associate the alias with the path.
*
*
* @param string $alias the alias name (e.g. "@rock"). It must start with a '@' character.
* It may contain the forward slash '/' which serves as boundary character when performing
* alias translation by {@see \rock\base\Alias::getAlias()}.
* @param string $path the path corresponding to the alias. Trailing '/' and '\' characters
* will be trimmed. This can be
*
* - a directory or a file path (e.g. `/tmp`, `/tmp/main.txt`)
* - a URL (e.g. `http://www.site.com`)
* - a path alias (e.g. `@rock/base`). In this case, the path alias will be converted into the
* actual path first by calling {@see \rock\base\Alias::getAlias()}.
*
* @param bool $trailingTrim any trailing '/' and '\' characters in the given path/url will be trimmed.
* @throws \Exception if $path is an invalid alias.
* @see getAlias()
*/
public static function setAlias($alias, $path, $trailingTrim = true)
{
if (strncmp($alias, '@', 1)) {
$alias = '@' . $alias;
}
$delimiter = ObjectHelper::isNamespace($alias) ? '\\' : '/';
$pos = strpos($alias, $delimiter);
$root = $pos === false ? $alias : substr($alias, 0, $pos);
if ($path !== null) {
if (!strncmp($path, '@', 1)) {
$path = static::getAlias($path);
} elseif ($trailingTrim) {
$path = rtrim($path, '\\/');
}
if (!isset(static::$aliases[$root])) {
if ($pos === false) {
static::$aliases[$root] = $path;
} else {
static::$aliases[$root] = [$alias => $path];
}
} elseif (is_string(static::$aliases[$root])) {
if ($pos === false) {
static::$aliases[$root] = $path;
} else {
static::$aliases[$root] = [$alias => $path, $root => static::$aliases[$root]];
}
} else {
static::$aliases[$root][$alias] = $path;
krsort(static::$aliases[$root]);
}
} elseif (isset(static::$aliases[$root])) {
if (is_array(static::$aliases[$root])) {
unset(static::$aliases[$root][$alias]);
} elseif ($pos === false) {
unset(static::$aliases[$root]);
}
}
}
