diff --git a/CHANGELOG.md b/CHANGELOG.md
index 1082888a5ec0..31284a4d69a8 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -12,6 +12,7 @@
 - `[jest-runtime]` Lock down version of `write-file-atomic` ([#7725](https://github.com/facebook/jest/pull/7725))
 - `[jest-cli]` Print log entries when logging happens after test environment is torn down ([#7731](https://github.com/facebook/jest/pull/7731))
 - `[jest-config]` Do not use a uuid as `name` since that breaks caching ([#7746](https://github.com/facebook/jest/pull/7746))
+- `[jest-config]` Make sure `normalize` can consume `Defaults` without warnings ([#7742](https://github.com/facebook/jest/pull/7742))
 
 ### Chore & Maintenance
 
diff --git a/packages/jest-config/src/Defaults.js b/packages/jest-config/src/Defaults.js
index 0bbdbdc7a432..f4eabb3168dc 100644
--- a/packages/jest-config/src/Defaults.js
+++ b/packages/jest-config/src/Defaults.js
@@ -31,8 +31,6 @@ export default ({
   coverageThreshold: null,
   cwd: process.cwd(),
   dependencyExtractor: null,
-  detectLeaks: false,
-  detectOpenHandles: false,
   errorOnDeprecated: false,
   expand: false,
   filter: null,
diff --git a/packages/jest-config/src/ValidConfig.js b/packages/jest-config/src/ValidConfig.js
index 238aee5dfee8..0b7a06adc64a 100644
--- a/packages/jest-config/src/ValidConfig.js
+++ b/packages/jest-config/src/ValidConfig.js
@@ -40,6 +40,7 @@ export default ({
       statements: 100,
     },
   },
+  cwd: '/root',
   dependencyExtractor: '<rootDir>/dependencyExtractor.js',
   displayName: 'project-name',
   errorOnDeprecated: false,
diff --git a/packages/jest-config/src/__tests__/normalize.test.js b/packages/jest-config/src/__tests__/normalize.test.js
index a1d37311d373..df031aadd292 100644
--- a/packages/jest-config/src/__tests__/normalize.test.js
+++ b/packages/jest-config/src/__tests__/normalize.test.js
@@ -10,6 +10,7 @@ import crypto from 'crypto';
 import path from 'path';
 import {escapeStrForRegex} from 'jest-regex-util';
 import normalize from '../normalize';
+import Defaults from '../Defaults';
 
 import {DEFAULT_JS_PATTERN} from '../constants';
 
@@ -45,6 +46,12 @@ beforeEach(() => {
   expectedPathAbsAnother = path.join(root, 'another', 'abs', 'path');
 
   require('jest-resolve').findNodeModule = findNodeModule;
+
+  jest.spyOn(console, 'warn');
+});
+
+afterEach(() => {
+  console.warn.mockRestore();
 });
 
 it('picks a name based on the rootDir', () => {
@@ -122,8 +129,7 @@ describe('rootDir', () => {
 
 describe('automock', () => {
   it('falsy automock is not overwritten', () => {
-    const consoleWarn = console.warn;
-    console.warn = jest.fn();
+    console.warn.mockImplementation(() => {});
     const {options} = normalize(
       {
         automock: false,
@@ -133,8 +139,6 @@ describe('automock', () => {
     );
 
     expect(options.automock).toBe(false);
-
-    console.warn = consoleWarn;
   });
 });
 
@@ -401,21 +405,15 @@ describe('setupFilesAfterEnv', () => {
 
 describe('setupTestFrameworkScriptFile', () => {
   let Resolver;
-  let consoleWarn;
 
   beforeEach(() => {
-    console.warn = jest.fn();
-    consoleWarn = console.warn;
+    console.warn.mockImplementation(() => {});
     Resolver = require('jest-resolve');
     Resolver.findNodeModule = jest.fn(name =>
       name.startsWith('/') ? name : '/root/path/foo' + path.sep + name,
     );
   });
 
-  afterEach(() => {
-    console.warn = consoleWarn;
-  });
-
   it('logs a deprecation warning when `setupTestFrameworkScriptFile` is used', () => {
     normalize(
       {
@@ -425,7 +423,7 @@ describe('setupTestFrameworkScriptFile', () => {
       {},
     );
 
-    expect(consoleWarn.mock.calls[0][0]).toMatchSnapshot();
+    expect(console.warn.mock.calls[0][0]).toMatchSnapshot();
   });
 
   it('logs an error when `setupTestFrameworkScriptFile` and `setupFilesAfterEnv` are used', () => {
@@ -782,11 +780,8 @@ describe('babel-jest', () => {
 });
 
 describe('Upgrade help', () => {
-  let consoleWarn;
-
   beforeEach(() => {
-    consoleWarn = console.warn;
-    console.warn = jest.fn();
+    console.warn.mockImplementation(() => {});
 
     const Resolver = require('jest-resolve');
     Resolver.findNodeModule = jest.fn(name => {
@@ -797,10 +792,6 @@ describe('Upgrade help', () => {
     });
   });
 
-  afterEach(() => {
-    console.warn = consoleWarn;
-  });
-
   it('logs a warning when `scriptPreprocessor` and/or `preprocessorIgnorePatterns` are used', () => {
     const {options: options, hasDeprecationWarnings} = normalize(
       {
@@ -1469,3 +1460,11 @@ describe('moduleFileExtensions', () => {
     ).toThrowError("moduleFileExtensions must include 'js'");
   });
 });
+
+describe('Defaults', () => {
+  it('should be accepted by normalize', () => {
+    normalize({...Defaults, rootDir: '/root'}, {});
+
+    expect(console.warn).not.toHaveBeenCalled();
+  });
+});
diff --git a/packages/jest-config/src/normalize.js b/packages/jest-config/src/normalize.js
index 6abbe34122e3..f2304fc71791 100644
--- a/packages/jest-config/src/normalize.js
+++ b/packages/jest-config/src/normalize.js
@@ -200,7 +200,9 @@ const normalizeCollectCoverageFrom = (options: InitialOptions, key: string) => {
       value = JSON.parse(options[key]);
     } catch (e) {}
 
-    Array.isArray(value) || (value = [options[key]]);
+    if (options[key] && !Array.isArray(value)) {
+      value = [options[key]];
+    }
   } else {
     value = options[key];
   }
diff --git a/types/Config.js b/types/Config.js
index d500cf4e7248..f4b14282cdfd 100644
--- a/types/Config.js
+++ b/types/Config.js
@@ -46,8 +46,6 @@ export type DefaultOptions = {|
   globalSetup: ?string,
   globalTeardown: ?string,
   haste: HasteConfig,
-  detectLeaks: boolean,
-  detectOpenHandles: boolean,
   moduleDirectories: Array<string>,
   moduleFileExtensions: Array<string>,
   moduleNameMapper: {[key: string]: string},