Add no-undefined-identifier rule

eslint/babel-eslint-plugin-development/src/rules/no-undefined-identifier.js

@@ -0,0 +1,41 @@
+"use strict";
+
+const getReferenceOrigin = require("../utils/get-reference-origin");
+const isFromBabelTypes = require("../utils/is-from-babel-types");
+
+function firstArgumentIsUndefinedString(argumentsArray) {
+  return (
+    argumentsArray.length > 0 &&
+    argumentsArray[0].type === "Literal" &&
+    argumentsArray[0].value === "undefined"
+  );
+}
+
+module.exports = {
+  meta: {
+    schema: [],
+  },
+  create(context) {
+    return {
+      CallExpression(node) {
+        const { callee } = node;
+        const scope = context.getScope();
+
+        const origin = getReferenceOrigin(callee, scope);
+        if (!origin) return;
+
+        const { name } = origin;
+        if (
+          (name === "identifier" || name === "Identifier") &&
+          firstArgumentIsUndefinedString(node.arguments) &&
+          isFromBabelTypes(origin, scope)
+        ) {
+          context.report(
+            node,
+            "Use path.scope.buildUndefinedNode() to create an undefined identifier directly.",
+          );
+        }
+      },
+    };
+  },
+};

eslint/babel-eslint-plugin-development/tests/rules/no-undefined-identifier.js

@@ -0,0 +1,80 @@
+"use strict";
+
+const rule = require("../../src/rules/no-undefined-identifier");
+const { RuleTester } = require("eslint");
+
+const error =
+  "Use path.scope.buildUndefinedNode() to create an undefined identifier directly.";
+
+const ruleTester = new RuleTester({
+  parserOptions: { sourceType: "module" },
+});
+
+ruleTester.run("no-undefined-identifier", rule, {
+  valid: [
+    `_.identifier("undefined")`,
+    `_.Identifier("undefined")`,
+    `import * as t from "lib"; t.identifier("undefined");`,
+    `function f(_) { _.types.identifier("undefined"); }`,
+    `import * as t from "@babel/types"; t.identifier("not_undefined");`,
+    `path.scope.buildUndefinedNode();`,
+  ],
+  invalid: [
+    {
+      code: `import { identifier } from "@babel/types"; identifier("undefined");`,
+      errors: [error],
+    },
+    {
+      code: `import { Identifier } from "@babel/types"; Identifier("undefined");`,
+      errors: [error],
+    },
+    {
+      code: `import * as t from "@babel/types"; t.identifier("undefined");`,
+      errors: [error],
+    },
+    {
+      code: `import * as t from "@babel/types"; var { identifier } = t; identifier("undefined");`,
+      errors: [error],
+    },
+    {
+      code: `import { identifier as id } from "@babel/types"; id("undefined");`,
+      errors: [error],
+    },
+    {
+      code: `import * as babel from "@babel/core"; babel.types.identifier("undefined");`,
+      errors: [error],
+    },
+    {
+      code: `import { types } from "@babel/core"; types.identifier("undefined");`,
+      errors: [error],
+    },
+    {
+      code: `import { types as t } from "@babel/core"; t.identifier("undefined");`,
+      errors: [error],
+    },
+    {
+      code: `export default function plugin(babel) { babel.types.identifier("undefined") }`,
+      errors: [error],
+    },
+    {
+      code: `export default function plugin({ types }) { types.identifier("undefined") }`,
+      errors: [error],
+    },
+    {
+      code: `export default function plugin({ types: t }) { t.identifier("undefined") }`,
+      errors: [error],
+    },
+    {
+      code: `export default ({ types }) => { types.identifier("undefined") }`,
+      errors: [error],
+    },
+    {
+      code: `module.exports = function plugin({ types }) { types.identifier("undefined") }`,
+      errors: [error],
+    },
+    {
+      code: `import { declare } from "@babel/helper-plugin-utils"; declare(({ types }) => { types.identifier("undefined") });`,
+      errors: [error],
+    },
+  ],
+});