| /** |
| * @fileoverview Rule to flag when initializing to undefined |
| * @author Ilya Volodin |
| */ |
| |
| "use strict"; |
| |
| const astUtils = require("./utils/ast-utils"); |
| |
| //------------------------------------------------------------------------------ |
| // Rule Definition |
| //------------------------------------------------------------------------------ |
| |
| module.exports = { |
| meta: { |
| type: "suggestion", |
| |
| docs: { |
| description: "disallow initializing variables to `undefined`", |
| category: "Variables", |
| recommended: false, |
| url: "https://eslint.org/docs/rules/no-undef-init" |
| }, |
| |
| schema: [], |
| fixable: "code" |
| }, |
| |
| create(context) { |
| |
| const sourceCode = context.getSourceCode(); |
| |
| return { |
| |
| VariableDeclarator(node) { |
| const name = sourceCode.getText(node.id), |
| init = node.init && node.init.name, |
| scope = context.getScope(), |
| undefinedVar = astUtils.getVariableByName(scope, "undefined"), |
| shadowed = undefinedVar && undefinedVar.defs.length > 0; |
| |
| if (init === "undefined" && node.parent.kind !== "const" && !shadowed) { |
| context.report({ |
| node, |
| message: "It's not necessary to initialize '{{name}}' to undefined.", |
| data: { name }, |
| fix(fixer) { |
| if (node.parent.kind === "var") { |
| return null; |
| } |
| |
| if (node.id.type === "ArrayPattern" || node.id.type === "ObjectPattern") { |
| |
| // Don't fix destructuring assignment to `undefined`. |
| return null; |
| } |
| return fixer.removeRange([node.id.range[1], node.range[1]]); |
| } |
| }); |
| } |
| } |
| }; |
| |
| } |
| }; |