diff --git a/README.md b/README.md
index babb04b..dee38c1 100644
--- a/README.md
+++ b/README.md
@@ -43,9 +43,10 @@ npm install assert-valid-glob-opts
 const assertValidGlobOpts = require('assert-valid-glob-opts');
 ```
 
-### assertValidGlobOpts(*obj*)
+### assertValidGlobOpts(*obj* [, *customValidations*])
 
 *obj*: `Object` ([`glob` options](https://github.com/isaacs/node-glob#options))  
+*customValidations*: `Array<Function>` (passed to [`validate-glob-opts`](https://github.com/shinnn/validate-glob-opts#validategloboptsobj--customvalidations))
 
 It validates a given object with [validate-glob-opts](https://github.com/shinnn/validate-glob-opts) and throws an error if the value is not valid.
 
diff --git a/index.js b/index.js
index 9e021b0..ec15c4c 100644
--- a/index.js
+++ b/index.js
@@ -7,8 +7,8 @@
 const GlobOptionError = require('glob-option-error');
 const validateGlobOpts = require('validate-glob-opts');
 
-module.exports = function assertValidGlobOpts(obj) {
-  const results = validateGlobOpts(obj);
+module.exports = function assertValidGlobOpts(...args) {
+  const results = validateGlobOpts(...args);
 
   if (results.length === 0) {
     return;
diff --git a/package.json b/package.json
index aa0dc2e..ff8c812 100644
--- a/package.json
+++ b/package.json
@@ -27,8 +27,8 @@
     "strict"
   ],
   "dependencies": {
-    "glob-option-error": "^0.1.0",
-    "validate-glob-opts": "^0.4.0"
+    "glob-option-error": "^1.0.0",
+    "validate-glob-opts": "^1.0.0"
   },
   "devDependencies": {
     "@shinnn/eslint-config-node": "^3.0.0",
diff --git a/test.js b/test.js
index 354b68a..69c40e9 100644
--- a/test.js
+++ b/test.js
@@ -9,6 +9,12 @@ test('assertValidGlobOpts()', t => {
     'should throw no errors when it takes no arguments.'
   );
 
+  t.throws(
+    () => main({}, [], null),
+    /^TypeError.*Expected 0, 1 or 2 arguments \(\[<object>, <array>]\), but got 3\./,
+    'should throw no errors when it takes too many arguments.'
+  );
+
   t.doesNotThrow(
     () => main({nodir: true}),
     'should throw no errors when it takes a valid glob option.'
@@ -16,7 +22,7 @@ test('assertValidGlobOpts()', t => {
 
   t.throws(
     () => main({cwd: 1}),
-    /^TypeError: node-glob expected `cwd` option to be a directory path \(string\), but got 1\./,
+    /^TypeError.*node-glob expected `cwd` option to be a directory path \(string\), but got 1 \(number\)\./,
     'should throw an error when it takes an invalid glob option.'
   );
 
@@ -32,5 +38,17 @@ test('assertValidGlobOpts()', t => {
     'should throw a type error when every error in the result is type error.'
   );
 
+  t.throws(
+    () => main({x: '!!!err!!!'}, [({x}) => new Error(x)]),
+    /^Error.*!!!err!!!/,
+    'should support custom validation parameter.'
+  );
+
+  t.throws(
+    () => main({}, new WeakMap()),
+    /^TypeError.*Expected an array of functions, but got a non-array value WeakMap {}\./,
+    'should invalidate the non-array second aergument.'
+  );
+
   t.end();
 });