From 25519a91ad58a63664e52562b7ea8fc1da6d4597 Mon Sep 17 00:00:00 2001
From: Craigory Coppola <craigorycoppola@gmail.com>
Date: Fri, 3 Sep 2021 14:40:56 -0400
Subject: [PATCH] fix(testing): fix(testing): support for typescript jest
 configs (#6920)

ISSUES CLOSED: #5394
---
 .../jest/src/executors/jest/jest.impl.spec.ts | 51 +++++++++++++++++--
 packages/jest/src/executors/jest/jest.impl.ts | 20 ++++----
 2 files changed, 56 insertions(+), 15 deletions(-)

diff --git a/packages/jest/src/executors/jest/jest.impl.spec.ts b/packages/jest/src/executors/jest/jest.impl.spec.ts
index 608b97e01f3dc..d9b644cb7ea02 100644
--- a/packages/jest/src/executors/jest/jest.impl.spec.ts
+++ b/packages/jest/src/executors/jest/jest.impl.spec.ts
@@ -1,10 +1,21 @@
 import { ExecutorContext } from '@nrwl/tao/src/shared/workspace';
+import * as fs from 'fs';
 
 let runCLI = jest.fn();
 jest.mock('jest', () => ({
   runCLI,
 }));
 
+// Mocking these 2 functions is required for jest-config
+// Otherwise, jest throws with "Can't find a root directory while resolving a config file path"
+jest.mock('fs', () => ({
+  ...(jest.requireActual('fs') as typeof fs),
+  existsSync: () => true,
+  lstatSync: () => ({
+    isDirectory: () => false,
+  }),
+}));
+
 import { jestExecutor } from './jest.impl';
 import { JestExecutorOptions } from './schema';
 
@@ -56,9 +67,7 @@ describe('Jest Executor', () => {
       jest.mock(
         '/root/jest.config.js',
         () => ({
-          transform: {
-            '^.+\\.[tj]sx?$': 'ts-jest',
-          },
+          transform: {},
         }),
         { virtual: true }
       );
@@ -172,7 +181,6 @@ describe('Jest Executor', () => {
           verbose: false,
           coverageReporters: ['test'],
           coverageDirectory: '/test/coverage',
-          testResultsProcessor: 'results-processor',
           updateSnapshot: true,
           useStderr: true,
           watch: false,
@@ -204,7 +212,6 @@ describe('Jest Executor', () => {
           reporters: ['/test/path'],
           coverageReporters: ['test'],
           coverageDirectory: '/root/test/coverage',
-          testResultsProcessor: 'results-processor',
           updateSnapshot: true,
           useStderr: true,
           watch: false,
@@ -324,4 +331,38 @@ describe('Jest Executor', () => {
       });
     });
   });
+
+  describe('when using typescript config file', () => {
+    beforeEach(() => {
+      jest.doMock(
+        '/root/jest.config.ts',
+        () => ({
+          transform: {
+            '^.+\\.[tj]sx?$': 'babel-jest',
+          },
+        }),
+        { virtual: true }
+      );
+      // jest.spyOn(tsNode, 'register').mockReturnValue(null)
+    });
+
+    it('should send appropriate options to jestCLI', async () => {
+      await jestExecutor(
+        {
+          ...defaultOptions,
+          jestConfig: './jest.config.ts',
+          watch: false,
+        },
+        mockContext
+      );
+      expect(runCLI).toHaveBeenCalledWith(
+        expect.objectContaining({
+          _: [],
+          testPathPattern: [],
+          watch: false,
+        }),
+        ['/root/jest.config.ts']
+      );
+    });
+  });
 });
diff --git a/packages/jest/src/executors/jest/jest.impl.ts b/packages/jest/src/executors/jest/jest.impl.ts
index 9bbf69873db8c..a427d710e6e45 100644
--- a/packages/jest/src/executors/jest/jest.impl.ts
+++ b/packages/jest/src/executors/jest/jest.impl.ts
@@ -16,18 +16,18 @@ export async function jestExecutor(
   options: JestExecutorOptions,
   context: ExecutorContext
 ): Promise<{ success: boolean }> {
-  const config = jestConfigParser(options, context);
+  const config = await jestConfigParser(options, context);
 
   const { results } = await runCLI(config, [options.jestConfig]);
 
   return { success: results.success };
 }
 
-export function jestConfigParser(
+export async function jestConfigParser(
   options: JestExecutorOptions,
   context: ExecutorContext,
   multiProjects = false
-): Config.Argv {
+): Promise<Config.Argv> {
   let jestConfig:
     | {
         transform: any;
@@ -36,12 +36,6 @@ export function jestConfigParser(
       }
     | undefined;
 
-  if (!multiProjects) {
-    options.jestConfig = path.resolve(context.root, options.jestConfig);
-
-    jestConfig = require(options.jestConfig);
-  }
-
   const config: Config.Argv = {
     $0: undefined,
     _: [],
@@ -73,6 +67,12 @@ export function jestConfigParser(
     watchAll: options.watchAll,
   };
 
+  if (!multiProjects) {
+    options.jestConfig = path.resolve(context.root, options.jestConfig);
+
+    jestConfig = (await readConfig(config, options.jestConfig)).projectConfig;
+  }
+
   // for backwards compatibility
   if (options.setupFile && !multiProjects) {
     const setupFilesAfterEnvSet = new Set([
@@ -132,7 +132,7 @@ export async function batchJest(
   );
 
   const { globalConfig, results } = await runCLI(
-    jestConfigParser(overrides, context, true),
+    await jestConfigParser(overrides, context, true),
     [...configPaths]
   );