Add custom eslint plugin to check fbjs imports

.eslintrc

@@ -17,7 +17,8 @@
     "flowtype",
     "prettier",
     "react",
-    "jest"
+    "jest",
+    "custom"
   ],
 
   // Map from global var to bool specifying if it can be redefined
@@ -262,5 +263,8 @@
     "jest/no-focused-tests": 1,
     "jest/no-identical-title": 1,
     "jest/valid-expect": 1,
+
+  // Custom rules, the plugin is located in the eslint-plugin folder.
+    "custom/fbjs-import": 1
   }
 }

eslint-plugin/index.js

@@ -0,0 +1,14 @@
+/**
+ * Copyright (c) 2015-present, Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ */
+
+const fbjsImportRule = require('./rules/fbjs-import');
+
+module.exports.rules = {
+  'fbjs-import': fbjsImportRule,
+};

eslint-plugin/package.json

@@ -0,0 +1,17 @@
+{
+  "name": "eslint-plugin-custom",
+  "version": "1.0.0",
+  "license": "BSD-3-Clause",
+  "description": "Custom ESLint rules used in the React Native repo",
+  "main": "index.js",
+  "engines": {
+    "node": ">=6"
+  },
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/facebook/react-native.git"
+  },
+  "dependencies": {
+    "eslint-module-utils": "^2.0.0"
+  }
+}

eslint-plugin/rules/fbjs-import.js

@@ -0,0 +1,57 @@
+/**
+ * Copyright (c) 2015-present, Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ */
+
+/**
+ * ESLint rule to avoid importing fbjs modules using haste, they should be imported
+ * using `fbjs/lib/<module>` otherwise it won't work in OSS.
+ */
+const fs = require('fs');
+const moduleVisitor = require('eslint-module-utils/moduleVisitor').default;
+const path = require('path');
+
+// Note that this file will be in the `<root>/node_modules/eslint-plugin-custom/rules`
+// folder when installed so file paths are relative to that.
+// Find modules that could be imported from fbjs.
+const fbjsFiles = fs
+  .readdirSync(path.resolve(__dirname, '../../fbjs/lib'))
+  .filter(file => file.match(/\.js$/g));
+
+// Find RN dependencies to avoid false positive if there is a commonjs module with
+// the same name as one of the fbjs modules.
+const reactNativePackageJSON = JSON.parse(
+  fs.readFileSync(path.resolve(__dirname, '../../../package.json'))
+);
+
+const fbjsModules = new Set(
+  fbjsFiles
+    .map(file => file.replace('.js', ''))
+    .filter(module => !reactNativePackageJSON.dependencies[module])
+);
+
+module.exports = {
+  create: context => {
+    const visitor = source => {
+      const moduleName = source.value;
+      if (fbjsModules.has(moduleName)) {
+        context.report({
+          node: source,
+          message: `fbjs module \`${moduleName}\` should not be imported using haste`,
+          fix: fixer => {
+            return fixer.insertTextBeforeRange(
+              [source.start + 1, source.end],
+              'fbjs/lib/'
+            );
+          },
+        });
+      }
+    };
+
+    return moduleVisitor(visitor, { commonjs: true });
+  },
+};

package.json

@@ -210,6 +210,7 @@
     "eslint-config-fb-strict": "^20.0.3",
     "eslint-config-fbjs": "^1.1.1",
     "eslint-plugin-eslint-comments": "^2.0.1",
+    "eslint-plugin-custom": "file:eslint-plugin",
     "eslint-plugin-flowtype": "^2.33.0",
     "eslint-plugin-jest": "^21.5.0",
     "eslint-plugin-prettier": "2.1.1",