public static function grab_deps( $file ) {
		if ( ! file_exists( $file ) ) {
			return [];
		}
		// @see {wp-includes/functions.php}
		$fp = fopen( $file, 'r' );
		$file_header = fread( $fp, 8192 );
		fclose( $fp );
		// Make sure we catch CR-only line endings.
		$file_header = str_replace( "\r", "\n", $file_header );
		// Grab dependencies.
		$regexp = '#wpdeps=(.*)$#um';
		if ( ! preg_match_all( $regexp, $file_header, $matches ) ) {
			return [];
		} else {
			list( $match, $deps ) = $matches;
			$deps = [];
			foreach ( $matches[1] as $dep ) {
				foreach ( array_map( 'trim', explode( ',', $dep ) ) as $d ) {
					if ( $d ) {
						$deps[] = $d;
					}
				}
			}
			return $deps;
		}
	}