feat: add no import expression eslint rule

.eslintrc.js

@@ -124,6 +124,7 @@ module.exports = {
         new: [],
       },
     ],
+    'react-internal/no-dynamic-import-in-literal': ERROR,
   },
 
   overrides: [
@@ -198,6 +199,7 @@ module.exports = {
         'jest/no-focused-tests': ERROR,
         'jest/valid-expect': ERROR,
         'jest/valid-expect-in-promise': ERROR,
+        'react-internal/no-dynamic-import-in-literal': OFF,
       },
     },
     {

scripts/eslint-rules/__tests__/no-dynamic-import-in-literal-test.internal.js

@@ -0,0 +1,52 @@
+/**
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @emails react-core
+ */
+
+'use strict';
+
+const rule = require('../no-dynamic-import-in-literal');
+const {RuleTester} = require('eslint');
+const ruleTester = new RuleTester({
+  parserOptions: {
+    ecmaVersion: 8,
+    sourceType: 'module',
+  },
+});
+
+ruleTester.run('eslint-rules/no-dynamic-import-in-literal', rule, {
+  valid: [
+    `console.log(
+      'import react from "react"'
+    )`,
+    `console.log(
+      'should work for non-import expression'
+    )`,
+  ],
+  invalid: [
+    {
+      code: `console.log(
+          'import("react")'
+        )`,
+      errors: [
+        {
+          message: 'Possible dynamic import expression in literal',
+        },
+      ],
+    },
+    {
+      code: `console.log(
+          'const MyComponent = lazy(() => import("./MyComponent"))'
+        )`,
+      errors: [
+        {
+          message: 'Possible dynamic import expression in literal',
+        },
+      ],
+    },
+  ],
+});

scripts/eslint-rules/index.js

@@ -11,5 +11,6 @@ module.exports = {
     'no-cross-fork-imports': require('./no-cross-fork-imports'),
     'no-cross-fork-types': require('./no-cross-fork-types'),
     'safe-string-coercion': require('./safe-string-coercion'),
+    'no-dynamic-import-in-literal': require('./no-dynamic-import-in-literal'),
   },
 };

scripts/eslint-rules/no-dynamic-import-in-literal.js

@@ -0,0 +1,34 @@
+/**
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @emails react-core
+ */
+
+'use strict';
+
+const IMPORT_PATTERN = /import\(([`'"]([^`'"]+)[`'"])*\)/;
+
+module.exports = {
+  meta: {
+    schema: [],
+  },
+  create(context) {
+    function checkIsImportExpression(node) {
+      const {type: nodeType} = node;
+      const content =
+        (nodeType === 'Literal' && node.value) ||
+        (nodeType === 'TemplateLiteral' && node.quasis[0].value.raw);
+      const isPossibleImportExpression = IMPORT_PATTERN.test(content);
+      if (isPossibleImportExpression) {
+        context.report(node, 'Possible dynamic import expression in literal');
+      }
+    }
+    return {
+      Literal: checkIsImportExpression,
+      TemplateLiteral: checkIsImportExpression,
+    };
+  },
+};