The "extends": "eslint:recommended" property in a configuration file enables this rule.
JavaScript environments contain a number of built-in global variables, such as window in browsers and process in Node.js. In almost all cases, you don’t want to assign a value to these global variables as doing so could result in losing access to important functionality. For example, you probably don’t want to do this in browser code:
window = {}; While examples such as window are obvious, there are often hundreds of built-in global objects provided by JavaScript environments. It can be hard to know if you’re assigning to a global variable or not.
This rule disallows modifications to read-only global variables.
ESLint has the capability to configure global variables as read-only.
Examples of incorrect code for this rule:
/*eslint no-global-assign: "error"*/ Object = null undefined = 1
/*eslint no-global-assign: "error"*/
/*eslint-env browser*/
window = {}
length = 1
top = 1 /*eslint no-global-assign: "error"*/ /*globals a:false*/ a = 1
Examples of correct code for this rule:
/*eslint no-global-assign: "error"*/ a = 1 var b = 1 b = 2
/*eslint no-global-assign: "error"*/
/*eslint-env browser*/
onload = function() {} /*eslint no-global-assign: "error"*/ /*globals a:true*/ a = 1
This rule accepts an exceptions option, which can be used to specify a list of builtins for which reassignments will be allowed:
{
"rules": {
"no-global-assign": ["error", {"exceptions": ["Object"]}]
}
} If you are trying to override one of the native objects.
This rule was introduced in ESLint 3.3.0.
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Licensed under the MIT License.
https://eslint.org/docs/rules/no-global-assign