import { RuleTester as ESLintTesterV8 } from 'eslint-v8'
import { RuleTester as ESLintTesterV9 } from 'eslint'
import { rules } from '@next/eslint-plugin-next'
const NextESLintRule = rules['no-page-custom-font']
const filename = 'pages/_document.js'
const tests = {
valid: [
{
code: `import Document, { Html, Head } from "next/document";
class MyDocument extends Document {
render() {
return (
);
}
}
export default MyDocument;`,
filename,
},
{
code: `import NextDocument, { Html, Head } from "next/document";
class Document extends NextDocument {
render() {
return (
);
}
}
export default Document;
`,
filename,
},
{
code: `export default function CustomDocument() {
return (
)
}`,
filename,
},
{
code: `function CustomDocument() {
return (
)
}
export default CustomDocument;
`,
filename,
},
{
code: `
import Document, { Html, Head } from "next/document";
class MyDocument {
render() {
return (
);
}
}
export default MyDocument;`,
filename,
},
{
code: `export default function() {
return (
)
}`,
filename,
},
],
invalid: [
{
code: `
import Head from 'next/head'
export default function IndexPage() {
return (
Hello world!
)
}
`,
filename: 'pages/index.tsx',
errors: [
{
message:
'Custom fonts not added in `pages/_document.js` will only load for a single page. This is discouraged. See: https://nextjs.org/docs/messages/no-page-custom-font',
type: 'JSXOpeningElement',
},
],
},
{
code: `
import Head from 'next/head'
function Links() {
return (
<>
)
}
export default function IndexPage() {
return (
Hello world!
)
}
`,
filename,
errors: [
{
message:
'Using `` outside of `` will disable automatic font optimization. This is discouraged. See: https://nextjs.org/docs/messages/no-page-custom-font',
},
{
message:
'Using `` outside of `` will disable automatic font optimization. This is discouraged. See: https://nextjs.org/docs/messages/no-page-custom-font',
},
],
},
],
}
describe('no-page-custom-font', () => {
new ESLintTesterV8({
parserOptions: {
ecmaVersion: 2018,
sourceType: 'module',
ecmaFeatures: {
modules: true,
jsx: true,
},
},
}).run('eslint-v8', NextESLintRule, tests)
new ESLintTesterV9({
languageOptions: {
ecmaVersion: 2018,
sourceType: 'module',
parserOptions: {
ecmaFeatures: {
modules: true,
jsx: true,
},
},
},
}).run('eslint-v9', NextESLintRule, tests)
})