noAlert

JavaScript (and super languages)

Summary

Rule available since: v2.1.0
Diagnostic Category: lint/suspicious/noAlert
This rule doesn’t have a fix.
The default severity of this rule is information.
Sources:
- Same as no-alert

Description

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.

Examples

Invalid

1
alert("here!");

code-block.js:1:1 lint/suspicious/noAlert ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ℹ Unexpected alert
  
  > 1 │ alert(“here!”);
      │ ^^^^^^^^^^^^^^
    2 │ 
  
  ℹ The alert function is considered to be obtrusive. Replace it with a custom UI implementation.

1
confirm("Are you sure?");

code-block.js:1:1 lint/suspicious/noAlert ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ℹ Unexpected confirm
  
  > 1 │ confirm(“Are you sure?”);
      │ ^^^^^^^^^^^^^^^^^^^^^^^^
    2 │ 
  
  ℹ The confirm function is considered to be obtrusive. Replace it with a custom UI implementation.

1
prompt("What's your name?", "John Doe");

code-block.js:1:1 lint/suspicious/noAlert ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ℹ Unexpected prompt
  
  > 1 │ prompt(“What’s your name?”, “John Doe”);
      │ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    2 │ 
  
  ℹ The prompt function is considered to be obtrusive. Replace it with a custom UI implementation.

Valid

1
customAlert("Something happened!");

1
customConfirm("Are you sure?");

1
customPrompt("Who are you?");

1
function foo() {
2
    const alert = myCustomLib.customAlert;
3
    alert();
4
}

How to configure

1
{
2
  "linter": {
3
    "rules": {
4
      "suspicious": {
5
        "noAlert": "error"
6
      }
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    }
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  }
9
}