📝 Disallow invalid values for HTML boolean attributes.
💼 This rule is enabled in the following configs: ✅ recommended, ☑️ unopinionated.
💡 This rule is manually fixable by editor suggestions.
HTML boolean attributes are true whenever they are present, regardless of their value. For example, button.setAttribute('disabled', 'false') still disables the button.
The HTML Standard permits only the empty string or the attribute's own name as its value, matched ASCII case-insensitively without leading or trailing whitespace. To represent false, remove the attribute.
This rule checks statically known primitive values passed to setAttribute() on identifiable native HTML elements. Non-string primitives are checked after conversion to strings, so both false and 'false' are reported.
const button = document.createElement('button');
// ❌
button.setAttribute('disabled', 'false');
button.setAttribute('disabled', false);
button.setAttribute('disabled', 'true');
button.setAttribute('disabled', ' disabled ');
// ✅
button.removeAttribute('disabled');
button.setAttribute('disabled', '');
button.setAttribute('disabled', 'disabled');
button.setAttribute('disabled', 'DISABLED');// ❌
const input = document.querySelector('input.required');
input?.setAttribute('required', 'false');
// ✅
input?.removeAttribute('required');
input?.setAttribute('required', '');Only boolean attributes applicable to the element are checked, per the HTML attribute index. ARIA, data-*, and enumerated attributes such as hidden are excluded.
Receivers are recognized through the global document's createElement(), HTML-namespace createElementNS(), or querySelector() with one tag and optional class/ID selectors. Simple const aliases are supported. Creation options, other documents/containers, and queries for SVG-ambiguous tags (a, script, style, title) are excluded.
Concrete native TypeScript annotations and assertions are supported. Type information also enables inferred types and JavaScript JSDoc annotations. Generic Element/HTMLElement types, subclasses, and structural lookalikes alone are insufficient. Input-state and document-tree restrictions are not analyzed.
For false or ASCII case-insensitive 'false' strings, the rule suggests removeAttribute(). Other invalid values get a suggestion to use ''. Suggestions that would remove or relocate comments are omitted. There is no autofix because behavior or attribute reads could change.
See also prefer-toggle-attribute for paired set/remove patterns.