Override-fn NPM

override-fn

util function to override any other function

Quick start

Several quick start options are available:

Download the latest release
Clone the repo: git clone https://github.com/massive-angular/override-fn.git
Install with bower: bower install override-fn
Install with npm: npm install override-fn

Examples

Use original parameters

var overrideFn = require('override-fn');

var context = {
    fn: function (a, b, c) {
        console.log('hello from fn: ', a, b, c);
    }
};

var originalFn = overrideFn(context, 'fn', function (baseFn) {
    console.log('hello from override-fn');
    baseFn();
});

context.fn(1, 2, 3);
// output:
// hello from override-fn
// hello from fn: 1, 2, 3

originalFn(1, 2, 3);
// output:
// hello from fn: 1, 2, 3

Use custom parameters

var overrideFn = require('override-fn');

var context = {
    fn: function (a, b, c) {
        console.log('hello from fn: ', a, b, c);
    }
};

var originalFn = overrideFn(context, 'fn', function (baseFn, a, b, c) {
    console.log('hello from override-fn');
    baseFn(a + 1, b + 1, c + 1);
});

context.fn(1, 2, 3);
// output:
// hello from override-fn
// hello from fn: 2, 3, 4

originalFn(1, 2, 3);
// output:
// hello from fn: 1, 2, 3

Override class

var overrideFn = require('override-fn');

var originalDate = overrideFn(global, 'Date', function (baseFn) {
    console.log('hello from override-fn');
    return baseFn(); // important to return created instance
});

var date = new Date();
console.log(date);
console.log(date instanceof Date);
console.log(date instanceof originalDate);
// output:
// hello from override-fn
// Tue May 24 2016 16:00:54 GMT+0300 (EEST)
// false
// true