diff --git a/src/TaskRunner.js b/src/TaskRunner.js
index eb2ff652..4bfe8d6c 100644
--- a/src/TaskRunner.js
+++ b/src/TaskRunner.js
@@ -49,12 +49,21 @@ export default class TaskRunner {
 
       this.worker = new Worker(workerPath, { numWorkers });
 
-      // Show syntax error from jest-worker
       // https://github.com/facebook/jest/issues/8872#issuecomment-524822081
+      const workerStdout = this.worker.getStdout();
+
+      if (workerStdout) {
+        workerStdout.on('data', (chunk) => {
+          return process.stdout.write(chunk);
+        });
+      }
+
       const workerStderr = this.worker.getStderr();
 
       if (workerStderr) {
-        workerStderr.pipe(process.stderr);
+        workerStderr.on('data', (chunk) => {
+          return process.stderr.write(chunk);
+        });
       }
     }
 
diff --git a/test/TerserPlugin.test.js b/test/TerserPlugin.test.js
index 08c52ee0..f86f60f2 100644
--- a/test/TerserPlugin.test.js
+++ b/test/TerserPlugin.test.js
@@ -10,6 +10,7 @@ import ChunkTemplate from 'webpack/lib/ChunkTemplate';
 import TerserPlugin from '../src/index';
 
 import {
+  BrokenCodePlugin,
   compile,
   countPlugins,
   getCompiler,
@@ -438,4 +439,134 @@ describe('TerserPlugin', () => {
     expect(getErrors(stats)).toMatchSnapshot('errors');
     expect(getWarnings(stats)).toMatchSnapshot('warnings');
   });
+
+  it('should emit an error on a broken code in parallel mode', async () => {
+    const compiler = getCompiler({
+      entry: {
+        one: `${__dirname}/fixtures/entry.js`,
+        two: `${__dirname}/fixtures/entry.js`,
+      },
+    });
+
+    new BrokenCodePlugin().apply(compiler);
+
+    new TerserPlugin({ parallel: true }).apply(compiler);
+
+    const stats = await compile(compiler);
+
+    expect(readsAssets(compiler, stats)).toMatchSnapshot('assets');
+    expect(getErrors(stats)).toMatchSnapshot('errors');
+    expect(getWarnings(stats)).toMatchSnapshot('warnings');
+  });
+
+  it('should emit an error on a broken code in not parallel mode', async () => {
+    const compiler = getCompiler({
+      entry: {
+        one: `${__dirname}/fixtures/entry.js`,
+        two: `${__dirname}/fixtures/entry.js`,
+      },
+    });
+
+    new BrokenCodePlugin().apply(compiler);
+
+    new TerserPlugin({ parallel: false }).apply(compiler);
+
+    const stats = await compile(compiler);
+
+    expect(readsAssets(compiler, stats)).toMatchSnapshot('assets');
+    expect(getErrors(stats)).toMatchSnapshot('errors');
+    expect(getWarnings(stats)).toMatchSnapshot('warnings');
+  });
+
+  it('should write stdout and stderr of workers to stdout and stderr of main process in parallel mode', async () => {
+    const { write: stdoutWrite } = process.stdout;
+    const { write: stderrWrite } = process.stderr;
+
+    let stdoutOutput = '';
+    let stderrOutput = '';
+
+    process.stdout.write = (str) => {
+      stdoutOutput += str;
+    };
+
+    process.stderr.write = (str) => {
+      stderrOutput += str;
+    };
+
+    const compiler = getCompiler({
+      entry: {
+        one: `${__dirname}/fixtures/empty.js`,
+        two: `${__dirname}/fixtures/empty.js`,
+      },
+    });
+
+    new TerserPlugin({
+      parallel: true,
+      minify: () => {
+        // eslint-disable-next-line no-console
+        process.stdout.write('stdout\n');
+        // eslint-disable-next-line no-console
+        process.stderr.write('stderr\n');
+
+        return { code: '' };
+      },
+    }).apply(compiler);
+
+    const stats = await compile(compiler);
+
+    expect(stdoutOutput).toMatchSnapshot('process stdout output');
+    expect(stderrOutput).toMatchSnapshot('process stderr output');
+    expect(readsAssets(compiler, stats)).toMatchSnapshot('assets');
+    expect(getErrors(stats)).toMatchSnapshot('errors');
+    expect(getWarnings(stats)).toMatchSnapshot('warnings');
+
+    process.stdout.write = stdoutWrite;
+    process.stderr.write = stderrWrite;
+  });
+
+  it('should write stdout and stderr of workers to stdout and stderr of main process in not parallel mode', async () => {
+    const { write: stdoutWrite } = process.stdout;
+    const { write: stderrWrite } = process.stderr;
+
+    let stdoutOutput = '';
+    let stderrOutput = '';
+
+    process.stdout.write = (str) => {
+      stdoutOutput += str;
+    };
+
+    process.stderr.write = (str) => {
+      stderrOutput += str;
+    };
+
+    const compiler = getCompiler({
+      entry: {
+        one: `${__dirname}/fixtures/empty.js`,
+        two: `${__dirname}/fixtures/empty.js`,
+      },
+    });
+
+    new TerserPlugin({
+      parallel: false,
+      minify: () => {
+        // eslint-disable-next-line no-console
+        process.stdout.write('stdout\n');
+        // eslint-disable-next-line no-console
+        process.stderr.write('stderr\n');
+
+        return { code: '' };
+      },
+    }).apply(compiler);
+
+    const stats = await compile(compiler);
+
+    expect(stdoutOutput).toMatchSnapshot('process stdout output');
+    expect(stderrOutput).toMatchSnapshot('process stderr output');
+    expect(readsAssets(compiler, stats)).toMatchSnapshot('assets');
+    expect(getErrors(stats)).toMatchSnapshot('errors');
+    expect(getWarnings(stats)).toMatchSnapshot('warnings');
+
+    process.stdout.write = stdoutWrite;
+    process.stderr.write = stderrWrite;
+  });
 });
diff --git a/test/__snapshots__/TerserPlugin.test.js.snap.webpack4 b/test/__snapshots__/TerserPlugin.test.js.snap.webpack4
index be37dbb4..43fdf8ec 100644
--- a/test/__snapshots__/TerserPlugin.test.js.snap.webpack4
+++ b/test/__snapshots__/TerserPlugin.test.js.snap.webpack4
@@ -68,6 +68,40 @@ exports[`TerserPlugin buildWarning method 5`] = `"Terser Plugin: Warning [http:/
 
 exports[`TerserPlugin buildWarning method 6`] = `null`;
 
+exports[`TerserPlugin should emit an error on a broken code in not parallel mode: assets 1`] = `
+Object {
+  "broken.js": "\`Broken===",
+  "one.js": "!function(e){var t={};function n(r){if(t[r])return t[r].exports;var o=t[r]={i:r,l:!1,exports:{}};return e[r].call(o.exports,o,o.exports,n),o.l=!0,o.exports}n.m=e,n.c=t,n.d=function(e,t,r){n.o(e,t)||Object.defineProperty(e,t,{enumerable:!0,get:r})},n.r=function(e){\\"undefined\\"!=typeof Symbol&&Symbol.toStringTag&&Object.defineProperty(e,Symbol.toStringTag,{value:\\"Module\\"}),Object.defineProperty(e,\\"__esModule\\",{value:!0})},n.t=function(e,t){if(1&t&&(e=n(e)),8&t)return e;if(4&t&&\\"object\\"==typeof e&&e&&e.__esModule)return e;var r=Object.create(null);if(n.r(r),Object.defineProperty(r,\\"default\\",{enumerable:!0,value:e}),2&t&&\\"string\\"!=typeof e)for(var o in e)n.d(r,o,function(t){return e[t]}.bind(null,o));return r},n.n=function(e){var t=e&&e.__esModule?function(){return e.default}:function(){return e};return n.d(t,\\"a\\",t),t},n.o=function(e,t){return Object.prototype.hasOwnProperty.call(e,t)},n.p=\\"\\",n(n.s=0)}([function(e,t){e.exports=function(){console.log(7)}}]);",
+  "two.js": "!function(e){var t={};function n(r){if(t[r])return t[r].exports;var o=t[r]={i:r,l:!1,exports:{}};return e[r].call(o.exports,o,o.exports,n),o.l=!0,o.exports}n.m=e,n.c=t,n.d=function(e,t,r){n.o(e,t)||Object.defineProperty(e,t,{enumerable:!0,get:r})},n.r=function(e){\\"undefined\\"!=typeof Symbol&&Symbol.toStringTag&&Object.defineProperty(e,Symbol.toStringTag,{value:\\"Module\\"}),Object.defineProperty(e,\\"__esModule\\",{value:!0})},n.t=function(e,t){if(1&t&&(e=n(e)),8&t)return e;if(4&t&&\\"object\\"==typeof e&&e&&e.__esModule)return e;var r=Object.create(null);if(n.r(r),Object.defineProperty(r,\\"default\\",{enumerable:!0,value:e}),2&t&&\\"string\\"!=typeof e)for(var o in e)n.d(r,o,function(t){return e[t]}.bind(null,o));return r},n.n=function(e){var t=e&&e.__esModule?function(){return e.default}:function(){return e};return n.d(t,\\"a\\",t),t},n.o=function(e,t){return Object.prototype.hasOwnProperty.call(e,t)},n.p=\\"\\",n(n.s=0)}([function(e,t){e.exports=function(){console.log(7)}}]);",
+}
+`;
+
+exports[`TerserPlugin should emit an error on a broken code in not parallel mode: errors 1`] = `
+Array [
+  "Error: broken.js from Terser
+Unterminated template [broken.js:1,0]",
+]
+`;
+
+exports[`TerserPlugin should emit an error on a broken code in not parallel mode: warnings 1`] = `Array []`;
+
+exports[`TerserPlugin should emit an error on a broken code in parallel mode: assets 1`] = `
+Object {
+  "broken.js": "\`Broken===",
+  "one.js": "!function(e){var t={};function n(r){if(t[r])return t[r].exports;var o=t[r]={i:r,l:!1,exports:{}};return e[r].call(o.exports,o,o.exports,n),o.l=!0,o.exports}n.m=e,n.c=t,n.d=function(e,t,r){n.o(e,t)||Object.defineProperty(e,t,{enumerable:!0,get:r})},n.r=function(e){\\"undefined\\"!=typeof Symbol&&Symbol.toStringTag&&Object.defineProperty(e,Symbol.toStringTag,{value:\\"Module\\"}),Object.defineProperty(e,\\"__esModule\\",{value:!0})},n.t=function(e,t){if(1&t&&(e=n(e)),8&t)return e;if(4&t&&\\"object\\"==typeof e&&e&&e.__esModule)return e;var r=Object.create(null);if(n.r(r),Object.defineProperty(r,\\"default\\",{enumerable:!0,value:e}),2&t&&\\"string\\"!=typeof e)for(var o in e)n.d(r,o,function(t){return e[t]}.bind(null,o));return r},n.n=function(e){var t=e&&e.__esModule?function(){return e.default}:function(){return e};return n.d(t,\\"a\\",t),t},n.o=function(e,t){return Object.prototype.hasOwnProperty.call(e,t)},n.p=\\"\\",n(n.s=0)}([function(e,t){e.exports=function(){console.log(7)}}]);",
+  "two.js": "!function(e){var t={};function n(r){if(t[r])return t[r].exports;var o=t[r]={i:r,l:!1,exports:{}};return e[r].call(o.exports,o,o.exports,n),o.l=!0,o.exports}n.m=e,n.c=t,n.d=function(e,t,r){n.o(e,t)||Object.defineProperty(e,t,{enumerable:!0,get:r})},n.r=function(e){\\"undefined\\"!=typeof Symbol&&Symbol.toStringTag&&Object.defineProperty(e,Symbol.toStringTag,{value:\\"Module\\"}),Object.defineProperty(e,\\"__esModule\\",{value:!0})},n.t=function(e,t){if(1&t&&(e=n(e)),8&t)return e;if(4&t&&\\"object\\"==typeof e&&e&&e.__esModule)return e;var r=Object.create(null);if(n.r(r),Object.defineProperty(r,\\"default\\",{enumerable:!0,value:e}),2&t&&\\"string\\"!=typeof e)for(var o in e)n.d(r,o,function(t){return e[t]}.bind(null,o));return r},n.n=function(e){var t=e&&e.__esModule?function(){return e.default}:function(){return e};return n.d(t,\\"a\\",t),t},n.o=function(e,t){return Object.prototype.hasOwnProperty.call(e,t)},n.p=\\"\\",n(n.s=0)}([function(e,t){e.exports=function(){console.log(7)}}]);",
+}
+`;
+
+exports[`TerserPlugin should emit an error on a broken code in parallel mode: errors 1`] = `
+Array [
+  "Error: broken.js from Terser
+Unterminated template [broken.js:1,0]",
+]
+`;
+
+exports[`TerserPlugin should emit an error on a broken code in parallel mode: warnings 1`] = `Array []`;
+
 exports[`TerserPlugin should regenerate hash: assets 1`] = `
 Object {
   "4.4.f1a57a9ca1b30ec6dc5a.js": "(window.webpackJsonp=window.webpackJsonp||[]).push([[4],{4:function(n,p,s){\\"use strict\\";s.r(p),p.default=\\"async-dep\\"}}]);",
@@ -313,3 +347,49 @@ exports[`TerserPlugin should work in multi compiler mode: warnings 1`] = `Array
 exports[`TerserPlugin should work in multi compiler mode: warnings 2`] = `Array []`;
 
 exports[`TerserPlugin should work in multi compiler mode: warnings 3`] = `Array []`;
+
+exports[`TerserPlugin should write stdout and stderr of workers to stdout and stderr of main process in not parallel mode: assets 1`] = `
+Object {
+  "one.js": "",
+  "two.js": "",
+}
+`;
+
+exports[`TerserPlugin should write stdout and stderr of workers to stdout and stderr of main process in not parallel mode: errors 1`] = `Array []`;
+
+exports[`TerserPlugin should write stdout and stderr of workers to stdout and stderr of main process in not parallel mode: process stderr output 1`] = `
+"stderr
+stderr
+"
+`;
+
+exports[`TerserPlugin should write stdout and stderr of workers to stdout and stderr of main process in not parallel mode: process stdout output 1`] = `
+"stdout
+stdout
+"
+`;
+
+exports[`TerserPlugin should write stdout and stderr of workers to stdout and stderr of main process in not parallel mode: warnings 1`] = `Array []`;
+
+exports[`TerserPlugin should write stdout and stderr of workers to stdout and stderr of main process in parallel mode: assets 1`] = `
+Object {
+  "one.js": "",
+  "two.js": "",
+}
+`;
+
+exports[`TerserPlugin should write stdout and stderr of workers to stdout and stderr of main process in parallel mode: errors 1`] = `Array []`;
+
+exports[`TerserPlugin should write stdout and stderr of workers to stdout and stderr of main process in parallel mode: process stderr output 1`] = `
+"stderr
+stderr
+"
+`;
+
+exports[`TerserPlugin should write stdout and stderr of workers to stdout and stderr of main process in parallel mode: process stdout output 1`] = `
+"stdout
+stdout
+"
+`;
+
+exports[`TerserPlugin should write stdout and stderr of workers to stdout and stderr of main process in parallel mode: warnings 1`] = `Array []`;
diff --git a/test/__snapshots__/TerserPlugin.test.js.snap.webpack5 b/test/__snapshots__/TerserPlugin.test.js.snap.webpack5
index 19860644..85da1b9f 100644
--- a/test/__snapshots__/TerserPlugin.test.js.snap.webpack5
+++ b/test/__snapshots__/TerserPlugin.test.js.snap.webpack5
@@ -68,6 +68,40 @@ exports[`TerserPlugin buildWarning method 5`] = `"Terser Plugin: Warning [http:/
 
 exports[`TerserPlugin buildWarning method 6`] = `null`;
 
+exports[`TerserPlugin should emit an error on a broken code in not parallel mode: assets 1`] = `
+Object {
+  "broken.js": "\`Broken===",
+  "one.js": "(()=>{var r={791:r=>{r.exports=function(){console.log(7)}}},o={};!function t(e){if(o[e])return o[e].exports;var n=o[e]={exports:{}};return r[e](n,n.exports,t),n.exports}(791)})();",
+  "two.js": "(()=>{var r={791:r=>{r.exports=function(){console.log(7)}}},o={};!function t(e){if(o[e])return o[e].exports;var n=o[e]={exports:{}};return r[e](n,n.exports,t),n.exports}(791)})();",
+}
+`;
+
+exports[`TerserPlugin should emit an error on a broken code in not parallel mode: errors 1`] = `
+Array [
+  "Error: broken.js from Terser
+Unterminated template [broken.js:1,0]",
+]
+`;
+
+exports[`TerserPlugin should emit an error on a broken code in not parallel mode: warnings 1`] = `Array []`;
+
+exports[`TerserPlugin should emit an error on a broken code in parallel mode: assets 1`] = `
+Object {
+  "broken.js": "\`Broken===",
+  "one.js": "(()=>{var r={791:r=>{r.exports=function(){console.log(7)}}},o={};!function t(e){if(o[e])return o[e].exports;var n=o[e]={exports:{}};return r[e](n,n.exports,t),n.exports}(791)})();",
+  "two.js": "(()=>{var r={791:r=>{r.exports=function(){console.log(7)}}},o={};!function t(e){if(o[e])return o[e].exports;var n=o[e]={exports:{}};return r[e](n,n.exports,t),n.exports}(791)})();",
+}
+`;
+
+exports[`TerserPlugin should emit an error on a broken code in parallel mode: errors 1`] = `
+Array [
+  "Error: broken.js from Terser
+Unterminated template [broken.js:1,0]",
+]
+`;
+
+exports[`TerserPlugin should emit an error on a broken code in parallel mode: warnings 1`] = `Array []`;
+
 exports[`TerserPlugin should regenerate hash: assets 1`] = `
 Object {
   "598.598.231e24cc7ba6b0dd72f5.js": "(window.webpackJsonp=window.webpackJsonp||[]).push([[598],{598:(s,n,p)=>{\\"use strict\\";p.r(n),p.d(n,{default:()=>w});const w=\\"async-dep\\"}}]);",
@@ -261,3 +295,49 @@ exports[`TerserPlugin should work in multi compiler mode: warnings 1`] = `Array
 exports[`TerserPlugin should work in multi compiler mode: warnings 2`] = `Array []`;
 
 exports[`TerserPlugin should work in multi compiler mode: warnings 3`] = `Array []`;
+
+exports[`TerserPlugin should write stdout and stderr of workers to stdout and stderr of main process in not parallel mode: assets 1`] = `
+Object {
+  "one.js": "",
+  "two.js": "",
+}
+`;
+
+exports[`TerserPlugin should write stdout and stderr of workers to stdout and stderr of main process in not parallel mode: errors 1`] = `Array []`;
+
+exports[`TerserPlugin should write stdout and stderr of workers to stdout and stderr of main process in not parallel mode: process stderr output 1`] = `
+"stderr
+stderr
+"
+`;
+
+exports[`TerserPlugin should write stdout and stderr of workers to stdout and stderr of main process in not parallel mode: process stdout output 1`] = `
+"stdout
+stdout
+"
+`;
+
+exports[`TerserPlugin should write stdout and stderr of workers to stdout and stderr of main process in not parallel mode: warnings 1`] = `Array []`;
+
+exports[`TerserPlugin should write stdout and stderr of workers to stdout and stderr of main process in parallel mode: assets 1`] = `
+Object {
+  "one.js": "",
+  "two.js": "",
+}
+`;
+
+exports[`TerserPlugin should write stdout and stderr of workers to stdout and stderr of main process in parallel mode: errors 1`] = `Array []`;
+
+exports[`TerserPlugin should write stdout and stderr of workers to stdout and stderr of main process in parallel mode: process stderr output 1`] = `
+"stderr
+stderr
+"
+`;
+
+exports[`TerserPlugin should write stdout and stderr of workers to stdout and stderr of main process in parallel mode: process stdout output 1`] = `
+"stdout
+stdout
+"
+`;
+
+exports[`TerserPlugin should write stdout and stderr of workers to stdout and stderr of main process in parallel mode: warnings 1`] = `Array []`;
diff --git a/test/__snapshots__/parallel-option-failure.test.js.snap.webpack4 b/test/__snapshots__/parallel-option-failure.test.js.snap.webpack4
deleted file mode 100644
index 41faf0fb..00000000
--- a/test/__snapshots__/parallel-option-failure.test.js.snap.webpack4
+++ /dev/null
@@ -1,23 +0,0 @@
-// Jest Snapshot v1, https://goo.gl/fbAQLP
-
-exports[`parallel option should match snapshot for errors into the "jest-worker" package whe the "cache" option is "true": errors 1`] = `
-Array [
-  "Error: one.js from Terser
-Error: jest-worker failed",
-  "Error: two.js from Terser
-Error: jest-worker failed",
-]
-`;
-
-exports[`parallel option should match snapshot for errors into the "jest-worker" package whe the "cache" option is "true": warnings 1`] = `Array []`;
-
-exports[`parallel option should match snapshot for errors into the "jest-worker" package: errors 1`] = `
-Array [
-  "Error: one.js from Terser
-Error: jest-worker failed",
-  "Error: two.js from Terser
-Error: jest-worker failed",
-]
-`;
-
-exports[`parallel option should match snapshot for errors into the "jest-worker" package: warnings 1`] = `Array []`;
diff --git a/test/__snapshots__/parallel-option-failure.test.js.snap.webpack5 b/test/__snapshots__/parallel-option-failure.test.js.snap.webpack5
deleted file mode 100644
index 59a76d41..00000000
--- a/test/__snapshots__/parallel-option-failure.test.js.snap.webpack5
+++ /dev/null
@@ -1,12 +0,0 @@
-// Jest Snapshot v1, https://goo.gl/fbAQLP
-
-exports[`parallel option should match snapshot for errors into the "jest-worker" package: errors 1`] = `
-Array [
-  "Error: one.js from Terser
-Error: jest-worker failed",
-  "Error: two.js from Terser
-Error: jest-worker failed",
-]
-`;
-
-exports[`parallel option should match snapshot for errors into the "jest-worker" package: warnings 1`] = `Array []`;
diff --git a/test/fixtures/empty.js b/test/fixtures/empty.js
new file mode 100644
index 00000000..e69de29b
diff --git a/test/helpers/BrokenCodePlugin.js b/test/helpers/BrokenCodePlugin.js
new file mode 100644
index 00000000..231b3ba9
--- /dev/null
+++ b/test/helpers/BrokenCodePlugin.js
@@ -0,0 +1,16 @@
+import { RawSource } from 'webpack-sources';
+
+export default class BrokenCodePlugin {
+  apply(compiler) {
+    const plugin = { name: this.constructor.name };
+
+    compiler.hooks.compilation.tap(plugin, (compilation) => {
+      compilation.hooks.additionalChunkAssets.tap(plugin, () => {
+        compilation.additionalChunkAssets.push('broken.js');
+
+        // eslint-disable-next-line no-param-reassign
+        compilation.assets['broken.js'] = new RawSource('`Broken===');
+      });
+    });
+  }
+}
diff --git a/test/helpers/getCompiler.js b/test/helpers/getCompiler.js
index 7f14a00d..6d4b625d 100644
--- a/test/helpers/getCompiler.js
+++ b/test/helpers/getCompiler.js
@@ -14,6 +14,7 @@ export default function getCompiler(options = {}) {
           entry: path.resolve(__dirname, '../fixtures/entry.js'),
           optimization: {
             minimize: false,
+            noEmitOnErrors: false,
           },
           output: {
             pathinfo: false,
diff --git a/test/helpers/index.js b/test/helpers/index.js
index e7c7bdd3..ccddbb17 100644
--- a/test/helpers/index.js
+++ b/test/helpers/index.js
@@ -1,3 +1,4 @@
+import BrokenCodePlugin from './BrokenCodePlugin';
 import compile from './compile';
 import countPlugins from './countPlugins';
 import execute from './execute';
@@ -11,6 +12,7 @@ import normalizeErrors from './normalizeErrors';
 import removeCache from './removeCache';
 
 export {
+  BrokenCodePlugin,
   compile,
   countPlugins,
   execute,
diff --git a/test/parallel-option-failure.test.js b/test/parallel-option-failure.test.js
deleted file mode 100644
index 0dcc6532..00000000
--- a/test/parallel-option-failure.test.js
+++ /dev/null
@@ -1,117 +0,0 @@
-import os from 'os';
-
-import Worker from 'jest-worker';
-
-import TerserPlugin from '../src/index';
-
-import {
-  compile,
-  getCompiler,
-  getErrors,
-  getWarnings,
-  removeCache,
-} from './helpers';
-
-jest.mock('os', () => {
-  const actualOs = require.requireActual('os');
-
-  actualOs.cpus = jest.fn(() => {
-    return { length: 4 };
-  });
-
-  return actualOs;
-});
-
-// Based on https://github.com/facebook/jest/blob/edde20f75665c2b1e3c8937f758902b5cf28a7b4/packages/jest-runner/src/__tests__/test_runner.test.js
-let workerTransform;
-let workerEnd;
-
-jest.mock('jest-worker', () => {
-  return jest.fn().mockImplementation(() => {
-    return {
-      // eslint-disable-next-line global-require, import/no-dynamic-require
-      transform: (workerTransform = jest.fn(() => {
-        throw new Error('jest-worker failed');
-      })),
-      end: (workerEnd = jest.fn()),
-      getStderr: jest.fn(() => {
-        console.warn('jest-worker warning from getStderr');
-      }),
-    };
-  });
-});
-
-const workerPath = require.resolve('../src/worker');
-
-describe('parallel option', () => {
-  let compiler;
-
-  beforeEach(() => {
-    jest.clearAllMocks();
-
-    compiler = getCompiler({
-      entry: {
-        one: `${__dirname}/fixtures/entry.js`,
-        two: `${__dirname}/fixtures/entry.js`,
-      },
-    });
-
-    return Promise.all([removeCache()]);
-  });
-
-  afterEach(() => Promise.all([removeCache()]));
-
-  it('should match snapshot for errors into the "jest-worker" package', async () => {
-    new TerserPlugin(
-      getCompiler.isWebpack4()
-        ? { parallel: true, cache: false }
-        : { parallel: true }
-    ).apply(compiler);
-
-    const warning = jest.spyOn(console, 'warn');
-
-    const stats = await compile(compiler);
-
-    expect(warning).toHaveBeenLastCalledWith(
-      'jest-worker warning from getStderr'
-    );
-
-    expect(Worker).toHaveBeenCalledTimes(1);
-    expect(Worker).toHaveBeenLastCalledWith(workerPath, {
-      numWorkers: Math.min(2, os.cpus().length - 1),
-    });
-    expect(workerTransform).toHaveBeenCalledTimes(
-      Object.keys(stats.compilation.assets).length
-    );
-    expect(workerEnd).toHaveBeenCalledTimes(1);
-
-    expect(getErrors(stats)).toMatchSnapshot('errors');
-    expect(getWarnings(stats)).toMatchSnapshot('warnings');
-  });
-
-  if (getCompiler.isWebpack4()) {
-    it('should match snapshot for errors into the "jest-worker" package whe the "cache" option is "true"', async () => {
-      new TerserPlugin({ parallel: true, cache: true }).apply(compiler);
-
-      const warning = jest.spyOn(console, 'warn');
-
-      const stats = await compile(compiler);
-
-      expect(warning).toHaveBeenLastCalledWith(
-        'jest-worker warning from getStderr'
-      );
-
-      expect(Worker).toHaveBeenCalledTimes(1);
-      expect(Worker).toHaveBeenLastCalledWith(workerPath, {
-        numWorkers: Math.min(2, os.cpus().length - 1),
-      });
-      expect(workerTransform).toHaveBeenCalledTimes(
-        Object.keys(stats.compilation.assets).length
-      );
-      expect(workerEnd).toHaveBeenCalledTimes(1);
-
-      expect(getErrors(stats)).toMatchSnapshot('errors');
-      expect(getWarnings(stats)).toMatchSnapshot('warnings');
-    });
-  }
-});
diff --git a/test/parallel-option.test.js b/test/parallel-option.test.js
index e26343d7..23aafcaf 100644
--- a/test/parallel-option.test.js
+++ b/test/parallel-option.test.js
@@ -37,6 +37,7 @@ jest.mock('jest-worker', () => {
       )),
       end: (workerEnd = jest.fn()),
       getStderr: jest.fn(),
+      getStdout: jest.fn(),
     };
   });
 });