4.7 KiB
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) {
.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');
assert
// 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) {
.string(foo, 'foo');
assert }
There you go. You can check that arrays are of a homogeneous type
with Arrayof$Type
:
function test(foo) {
.arrayOfString(foo, 'foo');
assert }
You can assert IFF an argument is not undefined
(i.e.,
an optional arg):
.optionalString(foo, 'foo'); assert
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. Be advised: The
standard functions re-exported from assert
are also
disabled in assert-plus if NDEBUG is specified. Using them directly from
the assert
module avoids this behavior.
The complete list of APIs is:
- assert.array
- assert.bool
- assert.buffer
- assert.func
- assert.number
- assert.finite
- assert.object
- assert.string
- assert.stream
- assert.date
- assert.regexp
- assert.uuid
- assert.arrayOfArray
- assert.arrayOfBool
- assert.arrayOfBuffer
- assert.arrayOfFunc
- assert.arrayOfNumber
- assert.arrayOfFinite
- assert.arrayOfObject
- assert.arrayOfString
- assert.arrayOfStream
- assert.arrayOfDate
- assert.arrayOfRegexp
- assert.arrayOfUuid
- assert.optionalArray
- assert.optionalBool
- assert.optionalBuffer
- assert.optionalFunc
- assert.optionalNumber
- assert.optionalFinite
- assert.optionalObject
- assert.optionalString
- assert.optionalStream
- assert.optionalDate
- assert.optionalRegexp
- assert.optionalUuid
- assert.optionalArrayOfArray
- assert.optionalArrayOfBool
- assert.optionalArrayOfBuffer
- assert.optionalArrayOfFunc
- assert.optionalArrayOfNumber
- assert.optionalArrayOfFinite
- assert.optionalArrayOfObject
- assert.optionalArrayOfString
- assert.optionalArrayOfStream
- assert.optionalArrayOfDate
- assert.optionalArrayOfRegexp
- assert.optionalArrayOfUuid
- 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.