diff --git a/packages/jest-environment-jsdom/src/index.js b/packages/jest-environment-jsdom/src/index.js index 6fa0c057eae7..b6acdc4d4ab5 100644 --- a/packages/jest-environment-jsdom/src/index.js +++ b/packages/jest-environment-jsdom/src/index.js @@ -23,7 +23,7 @@ class JSDOMEnvironment { errorEventListener: ?Function; moduleMocker: ?ModuleMocker; - constructor(config: ProjectConfig, options: EnvironmentOptions = {}) { + constructor(config: ProjectConfig, options?: EnvironmentOptions = {}) { this.dom = new JSDOM( '', Object.assign(