assert-plus
Extra assertions on top of node's assert module
node-assert-plus
This library is a super small wrapper over node's assert module that has two
things: (1) the ability to disable assertions with the environment variable
NODE_NDEBUG, and (2) some API wrappers for argument testing. Like
assert.string(myArg, 'myArg'). As a simple example, most of my code looks
like this:
var assert = require('assert-plus');
function fooAccount(options, callback) {
assert.object(options, 'options');
assert.number(options.id, 'options.id);
assert.bool(options.isManager, 'options.isManager');
assert.string(options.name, 'options.name');
assert.arrayOfString(options.email, 'options.email');
assert.func(callback, 'callback');
// Do stuff
callback(null, {});
}
API
All methods that aren't part of node's core assert API are simply assumed to
take an argument, and then a string 'name' that's not a message; AssertionError
will be thrown if the assertion fails with a message like:
AssertionError: foo (string) is required
at test (/home/mark/work/foo/foo.js:3:9)
at Object.<anonymous> (/home/mark/work/foo/foo.js:15:1)
at Module._compile (module.js:446:26)
at Object..js (module.js:464:10)
at Module.load (module.js:353:31)
at Function._load (module.js:311:12)
at Array.0 (module.js:484:10)
at EventEmitter._tickCallback (node.js:190:38)
from:
function test(foo) {
assert.string(foo, 'foo');
}
There you go. You can check that arrays are of a homogenous type with Arrayof$Type:
function test(foo) {
assert.arrayOfString(foo, 'foo');
}
You can assert IFF an argument is not (i.e., an optional arg):
assert.optionalString(foo, 'foo');
Lastly, you can opt-out of assertion checking altogether by setting the
environment variable NODE_NDEBUG=1. This is pseudo-useful if you have
lots of assertions, and don't want to pay typeof () taxes to v8 in
production.
The complete list of APIs is:
- assert.bool
- assert.buffer
- assert.func
- assert.number
- assert.object
- assert.string
- assert.arrayOfBool
- assert.arrayOfFunc
- assert.arrayOfNumber
- assert.arrayOfObject
- assert.arrayOfString
- assert.optionalBool
- assert.optionalBuffer
- assert.optionalFunc
- assert.optionalNumber
- assert.optionalObject
- assert.optionalString
- assert.optionalArrayOfBool
- assert.optionalArrayOfFunc
- assert.optionalArrayOfNumber
- assert.optionalArrayOfObject
- assert.optionalArrayOfString
- assert.AssertionError
- assert.fail
- assert.ok
- assert.equal
- assert.notEqual
- assert.deepEqual
- assert.notDeepEqual
- assert.strictEqual
- assert.notStrictEqual
- assert.throws
- assert.doesNotThrow
- assert.ifError
Installation
npm install assert-plus
License
The MIT License (MIT) Copyright (c) 2012 Mark Cavage
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
