Disallow the use of alert, confirm, and prompt

JavaScript’s alert, confirm, and prompt functions are widely considered to be obtrusive as UI elements and should be replaced by a more appropriate custom UI implementation. Furthermore, alert is often used while debugging code, which should be removed before deployment to production.


Rule Details

This rule is aimed at catching debugging code that should be removed and popup UI elements that should be replaced with less obtrusive, custom UIs. As such, it will warn when it encounters alert, prompt, and confirm function calls which are not shadowed.

Examples of incorrect code for this rule:

Open in Playground
/*eslint no-alert: "error"*/


confirm("Are you sure?");

prompt("What's your name?", "John Doe");

Examples of correct code for this rule:

Open in Playground
/*eslint no-alert: "error"*/

customAlert("Something happened!");

customConfirm("Are you sure?");

customPrompt("Who are you?");

function foo() {
    var alert = myCustomLib.customAlert;


This rule was introduced in ESLint v0.0.5.


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