diff --git a/types/shelljs/index.d.ts b/types/shelljs/index.d.ts
index 8d96561a1d..d20185e829 100644
--- a/types/shelljs/index.d.ts
+++ b/types/shelljs/index.d.ts
@@ -97,7 +97,7 @@ export function mkdir(options: string, ...dir: Array<string | string[]>): void;
  * @param   path   The path.
  * @return        See option parameter.
  */
-export function test(option: string, path: string): boolean;
+export function test(option: "-b" | "-c" | "-d" | "-e" | "-f" | "-L" | "-p" | "-S", path: string): boolean;
 
 /**
  * Returns a string containing the given file, or a concatenated string containing the files if more than one file is given (a new line character is introduced between each file). Wildcard * accepted.