@next/eslint-plugin-next
Version:
ESLint plugin for Next.js.
55 lines (54 loc) • 2.51 kB
JavaScript
;
var _definerule = require("../utils/define-rule");
var url = 'https://nextjs.org/docs/messages/no-duplicate-head';
module.exports = (0, _definerule.defineRule)({
meta: {
docs: {
description: 'Prevent duplicate usage of `<Head>` in `pages/_document.js`.',
recommended: true,
url: url
},
type: 'problem',
schema: []
},
create: function create(context) {
var sourceCode = context.sourceCode;
var documentImportName;
return {
ImportDeclaration: function ImportDeclaration(node) {
if (node.source.value === 'next/document') {
var documentImport = node.specifiers.find(function(param) {
var type = param.type;
return type === 'ImportDefaultSpecifier';
});
if (documentImport && documentImport.local) {
documentImportName = documentImport.local.name;
}
}
},
ReturnStatement: function ReturnStatement(node) {
var ancestors = sourceCode.getAncestors(node);
var documentClass = ancestors.find(function(ancestorNode) {
return ancestorNode.type === 'ClassDeclaration' && ancestorNode.superClass && 'name' in ancestorNode.superClass && ancestorNode.superClass.name === documentImportName;
});
if (!documentClass) {
return;
}
if (node.argument && 'children' in node.argument && node.argument.children) {
// @ts-expect-error - `node.argument` could be a `JSXElement` which has property `children`
var headComponents = node.argument.children.filter(function(childrenNode) {
return childrenNode.openingElement && childrenNode.openingElement.name && childrenNode.openingElement.name.name === 'Head';
});
if (headComponents.length > 1) {
for(var i = 1; i < headComponents.length; i++){
context.report({
node: headComponents[i],
message: "Do not include multiple instances of `<Head/>`. See: ".concat(url)
});
}
}
}
}
};
}
});