Add assert.ifError

diff --git a/doc/api.markdown b/doc/api.markdown
index 6afc466..c2467a1 100644 (file)
--- a/doc/api.markdown
+++ b/doc/api.markdown
@@ -2546,6 +2546,9 @@ Expects `block` to throw an error.
 
 Expects `block` not to throw an error.
 
+### assert.ifError(value)
+
+Tests if value is not a false value, throws if it is a true value. Useful when testing the first argument, `error` in callbacks.
 
 ## Path
 

diff --git a/lib/assert.js b/lib/assert.js
index da9198a..2d1fc08 100644 (file)
--- a/lib/assert.js
+++ b/lib/assert.js
@@ -284,3 +284,4 @@ assert.doesNotThrow = function(block, /*optional*/error, /*optional*/message) {
   _throws.apply(this, [false].concat(pSlice.call(arguments)));
 };
 
+assert.ifError = function (err) { if (err) {throw err;}};

diff --git a/test/simple/test-assert.js b/test/simple/test-assert.js
index 6102368..10aeb5c 100644 (file)
--- a/test/simple/test-assert.js
+++ b/test/simple/test-assert.js
@@ -154,3 +154,6 @@ try {
 }
 assert.equal(true,threw,'a.doesNotThrow is not catching type matching errors');
 
+assert.throws(function () {assert.ifError(new Error('test error'))});
+assert.doesNotThrow(function(){assert.ifError(null)});
+assert.doesNotThrow(function(){assert.ifError()});