Run with Jest Circus when passing the JEST_CIRCUS env variable as 1

integration-tests/__tests__/each.test.js

@@ -14,8 +14,10 @@ const runJest = require('../runJest');
 const {extractSummary} = require('../Utils');
 const dir = path.resolve(__dirname, '../each');
 const SkipOnWindows = require('../../scripts/SkipOnWindows');
+const SkipOnJestCircus = require('../../scripts/SkipOnJestCircus');
 
 SkipOnWindows.suite();
+SkipOnJestCircus.suite();
 
 test('works with passing tests', () => {
   const result = runJest(dir, ['success.test.js']);

packages/jest-runner/src/run_test.js

@@ -69,7 +69,11 @@ async function runTestInternal(
   /* $FlowFixMe */
   const TestEnvironment = (require(testEnvironment): EnvironmentClass);
   /* $FlowFixMe */
-  const testFramework = (require(config.testRunner): TestFramework);
+  const testFramework = ((process.env.JEST_CIRCUS === '1'
+    ? // eslint-disable-next-line import/no-extraneous-dependencies
+      require('jest-circus/build/legacy_code_todo_rewrite/jest_adapter.js')
+        .default
+    : require(config.testRunner)): TestFramework);
   /* $FlowFixMe */
   const Runtime = (require(config.moduleLoader || 'jest-runtime'): Class<
     RuntimeClass,

scripts/SkipOnJestCircus.js

@@ -0,0 +1,30 @@
+/**
+ * Copyright (c) 2014-present, Facebook, Inc. All rights reserved.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @flow
+ */
+
+/* eslint-disable jest/no-focused-tests */
+
+const SkipOnWindows = {
+  suite() {
+    if (process.env.JEST_CIRCUS === '1') {
+      fit('does not work on jest-circus', () => {
+        console.warn('[SKIP] Does not work on jest-circus');
+      });
+    }
+  },
+
+  test() {
+    if (process.env.JEST_CIRCUS === '1') {
+      console.warn('[SKIP] Does not work on jest-circus');
+      return true;
+    }
+    return false;
+  },
+};
+
+module.exports = SkipOnWindows;