Float is currently being tested only with the external runtime. This runtime is unstable and should not be part of stable builds and we should still be testing the integrated Fizz runtime. This change forks the Float tests to ensure we test with and without the external Fizz runtime

Author: gnoff

.eslintrc.js

@@ -336,7 +336,7 @@ module.exports = {
         'packages/eslint-plugin-react-hooks/**/*.js',
         'packages/jest-react/**/*.js',
         'packages/internal-test-utils/**/*.js',
-        'packages/**/__tests__/*.js',
+        'packages/**/__tests__/**/*.js',
         'packages/**/npm/*.js',
       ],
       rules: {

packages/react-dom/src/__tests__/ReactDOMFloat-test.external-runtime.js

@@ -0,0 +1,16 @@
+/**
+ * Copyright (c) Meta Platforms, Inc. and 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
+ * @jest-environment ./scripts/jest/ReactDOMServerIntegrationEnvironment
+ */
+
+'use strict';
+
+import {runTests} from './impl/ReactDOMFloat-test.impl';
+
+const usingExternalRuntime = true;
+runTests(usingExternalRuntime);