callback-binding.md

Callback binding

In Lodash version 3, it was possible to pass an additional parameter to methods that require binding, thisArg. However, in Lodash 4, this option was removed in favor of regular binding, and still using the old method could cause unexpected results.

Rule Details

This rule takes no arguments. However, it is affected by the lodash version defined in the config's shared settings for Lodash.

Lodash Version 4 (default)

In version 4, the following patterns are considered warnings:

var r = _.filter(users, function (user) {
    return user.age > this.age;
}, this);

var r = _.reduce(numbers, multiply, 1, this);

The following patterns are not considered warnings:

var r = _.filter(users, function (user) {
    return user.age > this.age;
}.bind(this));

Lodash version 3

In version 3, the following patterns are considered warnings:

var r = _.filter(users, function (user) {
    return user.age > this.age;
}, this);

The following patterns are not considered warnings:

var r = _.filter(users, function (user) {
    return user.age > this.age;
}.bind(this));