From 8c9e7f987e2a7b410f263aae3ab1ce1e7005472a Mon Sep 17 00:00:00 2001
From: Douglas Christopher Wilson <doug@somethingdoug.com>
Date: Fri, 12 Jun 2015 23:20:07 -0400
Subject: [PATCH] Improve error message when req argument missing

---
 HISTORY.md    |  1 +
 index.js      |  4 ++++
 test/index.js | 10 +++++++++-
 3 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/HISTORY.md b/HISTORY.md
index 016efff..9dab2a8 100644
--- a/HISTORY.md
+++ b/HISTORY.md
@@ -1,6 +1,7 @@
 unreleased
 ==========
 
+  * Improve error message when `req` argument missing
   * perf: enable strict mode
   * perf: hoist regular expression
   * perf: parse with regular expressions
diff --git a/index.js b/index.js
index 1e74955..ca0be71 100644
--- a/index.js
+++ b/index.js
@@ -46,6 +46,10 @@ var userPassRegExp = /^([^:]*):(.*)$/
  */
 
 function auth(req) {
+  if (!req) {
+    throw new TypeError('argument req is required')
+  }
+
   // get header
   var header = (req.req || req).headers.authorization
 
diff --git a/test/index.js b/test/index.js
index 65f791f..4375388 100644
--- a/test/index.js
+++ b/test/index.js
@@ -9,7 +9,15 @@ function request(authorization) {
   }
 }
 
-describe('auth(req)', function(){
+describe('auth(req)', function () {
+  describe('arguments', function () {
+    describe('req', function () {
+      it('should be required', function () {
+        assert.throws(auth, /argument req is required/)
+      })
+    })
+  })
+
   describe('with no Authorization field', function(){
     it('should return null', function(){
       var req = request();