| import { defineRule } from '../utils/define-rule' |
| import NodeAttributes from '../utils/node-attributes' |
|
|
| const url = 'https://nextjs.org/docs/messages/google-font-display' |
|
|
| export = defineRule({ |
| meta: { |
| docs: { |
| description: 'Enforce font-display behavior with Google Fonts.', |
| recommended: true, |
| url, |
| }, |
| type: 'problem', |
| schema: [], |
| }, |
| create(context) { |
| return { |
| JSXOpeningElement(node) { |
| let message: string | undefined |
|
|
| if (node.name.name !== 'link') { |
| return |
| } |
|
|
| const attributes = new NodeAttributes(node) |
| if (!attributes.has('href') || !attributes.hasValue('href')) { |
| return |
| } |
|
|
| const hrefValue = attributes.value('href') |
| const isGoogleFont = |
| typeof hrefValue === 'string' && |
| hrefValue.startsWith('https://fonts.googleapis.com/css') |
|
|
| if (isGoogleFont) { |
| const params = new URLSearchParams(hrefValue.split('?', 2)[1]) |
| const displayValue = params.get('display') |
|
|
| if (!params.has('display')) { |
| message = |
| 'A font-display parameter is missing (adding `&display=optional` is recommended).' |
| } else if ( |
| displayValue === 'auto' || |
| displayValue === 'block' || |
| displayValue === 'fallback' |
| ) { |
| message = `${ |
| displayValue[0].toUpperCase() + displayValue.slice(1) |
| } is not recommended.` |
| } |
| } |
|
|
| if (message) { |
| context.report({ |
| node, |
| message: `${message} See: ${url}`, |
| }) |
| } |
| }, |
| } |
| }, |
| }) |
|
|
