diff --git a/package.json b/package.json
index e1e12869..adbe9555 100644
--- a/package.json
+++ b/package.json
@@ -28,6 +28,7 @@
     "@oclif/tslint": "^1.1.2",
     "@types/ansi-styles": "^3.2.0",
     "@types/chai": "^4.1.3",
+    "@types/chai-as-promised": "^7.1.0",
     "@types/clean-stack": "^1.3.0",
     "@types/extract-stack": "^1.0.0",
     "@types/fs-extra": "^5.0.2",
@@ -39,6 +40,7 @@
     "@types/strip-ansi": "^3.0.0",
     "@types/supports-color": "^5.3.0",
     "chai": "^4.1.2",
+    "chai-as-promised": "^7.1.1",
     "concurrently": "^3.5.1",
     "eslint": "^4.19.1",
     "eslint-config-oclif": "^1.5.1",
diff --git a/test/prompt.test.ts b/test/prompt.test.ts
index 7603540d..06ec2d05 100644
--- a/test/prompt.test.ts
+++ b/test/prompt.test.ts
@@ -1,6 +1,12 @@
+import * as chai from 'chai'
+import chaiAsPromised from 'chai-as-promised'
+
+chai.use(chaiAsPromised)
+const expect = chai.expect
+
 import cli from '../src'
 
-import {expect, fancy} from './fancy'
+import {fancy} from './fancy'
 
 describe('prompt', () => {
   fancy
@@ -32,7 +38,7 @@ describe('prompt', () => {
   .stdout()
   .stderr()
   .end('timeouts with no input', async () => {
-    const response = await cli.prompt('Require input?', {timeout: 100})
-    expect(response).to.not.exist
+    await expect(cli.prompt('Require input?', {timeout: 1}))
+    .to.eventually.be.rejectedWith('timed out')
   })
 })
diff --git a/yarn.lock b/yarn.lock
index 7e783c21..87f80a4c 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -32,7 +32,13 @@
   dependencies:
     "@types/color-name" "*"
 
-"@types/chai@^4.1.3":
+"@types/chai-as-promised@^7.1.0":
+  version "7.1.0"
+  resolved "https://registry.yarnpkg.com/@types/chai-as-promised/-/chai-as-promised-7.1.0.tgz#010b04cde78eacfb6e72bfddb3e58fe23c2e78b9"
+  dependencies:
+    "@types/chai" "*"
+
+"@types/chai@*", "@types/chai@^4.1.3":
   version "4.1.3"
   resolved "https://registry.yarnpkg.com/@types/chai/-/chai-4.1.3.tgz#b8a74352977a23b604c01aa784f5b793443fb7dc"
 
@@ -225,6 +231,12 @@ cardinal@^2.1.1:
     ansicolors "~0.3.2"
     redeyed "~2.1.0"
 
+chai-as-promised@^7.1.1:
+  version "7.1.1"
+  resolved "https://registry.yarnpkg.com/chai-as-promised/-/chai-as-promised-7.1.1.tgz#08645d825deb8696ee61725dbf590c012eb00ca0"
+  dependencies:
+    check-error "^1.0.2"
+
 chai@^4.1.2:
   version "4.1.2"
   resolved "https://registry.yarnpkg.com/chai/-/chai-4.1.2.tgz#0f64584ba642f0f2ace2806279f4f06ca23ad73c"
@@ -276,7 +288,7 @@ chardet@^0.4.0:
   version "0.4.2"
   resolved "https://registry.yarnpkg.com/chardet/-/chardet-0.4.2.tgz#b5473b33dc97c424e5d98dc87d55d4d8a29c8bf2"
 
-check-error@^1.0.1:
+check-error@^1.0.1, check-error@^1.0.2:
   version "1.0.2"
   resolved "https://registry.yarnpkg.com/check-error/-/check-error-1.0.2.tgz#574d312edd88bb5dd8912e9286dd6c0aed4aac82"