framework/web/AssetManager.php
public function getPublishedUrl($path)
    {
        $path = Yii::getAlias($path);

        if (isset($this->_published[$path])) {
            return $this->_published[$path][1];
        }
        if (is_string($path) && ($path = realpath($path)) !== false) {
            return $this->baseUrl . '/' . $this->hash($path) . (is_file($path) ? '/' . basename($path) : '');
        }

        return false;
    }
public function getPublishedUrl($path)
    {
        $path = Yii::getAlias($path);

        if (isset($this->_published[$path])) {
            return $this->_published[$path][1];
        }
        if (is_string($path) && ($path = realpath($path)) !== false) {
            return $this->baseUrl . '/' . $this->hash($path) . (is_file($path) ? '/' . basename($path) : '');
        }

        return false;
    }
Returns the URL of a published file path.
This method does not perform any publishing. It merely tells you
if the file path is published, what the URL will be to access it.
@param string $path directory or file path being published
@return string|false string the published URL for the file or directory. False if the file or directory does not exist.