Awesome

underscore.assert

🔨 Plugin for Underscore.js: add method "_.assert", which simplify checking states

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Install

npm install underscore.assert

Usage

var _ = require('underscore');
var assert = require('underscore.assert');
_.mixin({ assert: assert });

_.assert(typeof fn === 'function', '*fn* should be function'); // throws AssertionError
_.assert(list.length > 0, '*list* should contains any value'); // throws ONLY when list is empty
_.assert(false); // => throw `AssertionError`
_.assert.ErrorConstructor = MyCustomError;
_.assert(false); // => throw `MyCustomError`

Example

Instead of this:

function isUrl(url) {
    if (typeof url === 'string') {
        throw new Error('URL should be a *string* value');
    }

    // ... URL validation
}

... you can that:

function isUrl(url) {
    _.assert(typeof url === 'string', 'URL should be a *string* value');
    // ... URL validation
}

Proposals

• This is not for specs files in project...
• This is not instead of Jasmine or any test framework...
• This is inline code for testing production code!

License

The MIT License @ 2013