Add Async Test Environment APIs

Author: xfumihiro

integration_tests/__tests__/test_environment.test.js

@@ -14,10 +14,9 @@ const runJest = require('../runJest');
 const testFixturePackage = require('../test-environment/package.json');
 
 it('respects testEnvironment docblock', () => {
-  expect(testFixturePackage.jest.testEnvironment).toEqual('node');
+  expect(testFixturePackage.jest.testEnvironment).toEqual('./test-environment');
 
-  const result = runJest.json('test-environment').json;
+  const result = runJest('test-environment');
 
-  expect(result.success).toBe(true);
-  expect(result.numTotalTests).toBe(1);
+  expect(result.stdout).toBe('teardown\n');
 });

integration_tests/test-environment/__tests__/env.test.js

@@ -5,7 +5,7 @@
  * 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.
  *
- * @jest-environment jsdom
+ * @jest-environment ./test-environment
  */
 'use strict';
 /* eslint-env browser*/
@@ -14,3 +14,7 @@ test('stub', () => {
   const element = document.createElement('div');
   expect(element).not.toBeNull();
 });
+
+test('stub2', () => {
+  expect(global.setup).toBe('setup');
+});

integration_tests/test-environment/package.json

@@ -1,5 +1,5 @@
 {
   "jest": {
-    "testEnvironment": "node"
+    "testEnvironment": "./test-environment"
   }
 }

integration_tests/test-environment/test-environment.js

@@ -0,0 +1,25 @@
+const JSDOMEnvironment = require('../../packages/jest-environment-jsdom');
+
+class TestEnvironment extends JSDOMEnvironment {
+  constructor(config) {
+    super(config);
+  }
+
+  async setup() {
+    this.global.setup = 'setup';
+  }
+
+  async teardown() {
+    console.log('teardown');
+  }
+
+  dispose() {
+    super.dispose();
+  }
+
+  runScript(script) {
+    return super.runScript(script);
+  }
+}
+
+module.exports = TestEnvironment;

packages/jest-environment-jsdom/src/index.js

@@ -37,6 +37,14 @@ class JSDOMEnvironment {
     this.fakeTimers = new FakeTimers(global, this.moduleMocker, config);
   }
 
+  setup(): Promise<void> {
+    return Promise.resolve();
+  }
+
+  teardown(): Promise<void> {
+    return Promise.resolve();
+  }
+
   dispose(): void {
     if (this.fakeTimers) {
       this.fakeTimers.dispose();

packages/jest-environment-node/src/index.js

@@ -37,6 +37,14 @@ class NodeEnvironment {
     this.fakeTimers = new FakeTimers(global, this.moduleMocker, config);
   }
 
+  setup(): Promise<void> {
+    return Promise.resolve();
+  }
+
+  teardown(): Promise<void> {
+    return Promise.resolve();
+  }
+
   dispose() {
     if (this.fakeTimers) {
       this.fakeTimers.dispose();

packages/jest-runner/src/run_test.js

@@ -12,7 +12,6 @@ import type {EnvironmentClass} from 'types/Environment';
 import type {GlobalConfig, Path, ProjectConfig} from 'types/Config';
 import type {Resolver} from 'types/Resolve';
 import type {TestFramework} from 'types/TestRunner';
-import type {TestResult} from 'types/TestResult';
 import type RuntimeClass from 'jest-runtime';
 
 import fs from 'fs';
@@ -100,8 +99,15 @@ export default function runTest(
     mapCoverage: globalConfig.mapCoverage,
   });
   const start = Date.now();
-  return testFramework(globalConfig, config, environment, runtime, path)
-    .then((result: TestResult) => {
+  return environment.setup().then(async () => {
+    try {
+      const result = await testFramework(
+        globalConfig,
+        config,
+        environment,
+        runtime,
+        path,
+      );
       const testCount =
         result.numPassingTests +
         result.numFailingTests +
@@ -113,26 +119,24 @@ export default function runTest(
       result.console = testConsole.getBuffer();
       result.skipped = testCount === result.numPendingTests;
       result.displayName = config.displayName;
-      return result;
-    })
-    .then(
-      result =>
-        Promise.resolve().then(() => {
-          environment.dispose();
-          if (globalConfig.logHeapUsage) {
-            if (global.gc) {
-              global.gc();
-            }
-            result.memoryUsage = process.memoryUsage().heapUsed;
-          }
-
-          // Delay the resolution to allow log messages to be output.
-          return new Promise(resolve => setImmediate(() => resolve(result)));
-        }),
-      err =>
-        Promise.resolve().then(() => {
-          environment.dispose();
-          throw err;
-        }),
-    );
+      if (environment.teardown) {
+        await environment.teardown();
+      }
+      environment.dispose();
+      if (globalConfig.logHeapUsage) {
+        if (global.gc) {
+          global.gc();
+        }
+        result.memoryUsage = process.memoryUsage().heapUsed;
+      }
+      // Delay the resolution to allow log messages to be output.
+      return new Promise(resolve => setImmediate(() => resolve(result)));
+    } catch (err) {
+      if (environment.teardown) {
+        await environment.teardown();
+      }
+      environment.dispose();
+      throw err;
+    }
+  });
 }

types/Environment.js

@@ -31,6 +31,8 @@ declare class $JestEnvironment {
   },
   testFilePath: string,
   moduleMocker: ModuleMocker,
+  setup(): Promise<void>,
+  teardown(): Promise<void>,
 }
 
 export type Environment = $JestEnvironment;