assertions.diff

diff --git a/lib/html-assertions.js b/lib/html-assertions.js
index 5626921..c8ef359 100644
--- a/lib/html-assertions.js
+++ b/lib/html-assertions.js
@@ -5,6 +5,12 @@ const dom = require('jsdom').jsdom(rawHtml)
 const document = dom
 const window = dom.defaultView
 
+const rejections = new Set()
+process.on('unhandledRejection', (err, p) => rejections.add(p))
+process.on('rejectionHandled', (err, p) => rejections.delete(p))
+process.on('exit', () => {
+  rejections.forEach(p => p.catch(console.log))
+})
 
 const existsFailMessage = selector => `Missing ${selector} element`
 const notExistsFailMessage = selector => `${selector} element should not exist`