replace jest with ava

node_modules/mimic-response/index.js

@@ -0,0 +1,32 @@
+'use strict';
+
+// We define these manually to ensure they're always copied
+// even if they would move up the prototype chain
+// https://nodejs.org/api/http.html#http_class_http_incomingmessage
+const knownProps = [
+	'destroy',
+	'setTimeout',
+	'socket',
+	'headers',
+	'trailers',
+	'rawHeaders',
+	'statusCode',
+	'httpVersion',
+	'httpVersionMinor',
+	'httpVersionMajor',
+	'rawTrailers',
+	'statusMessage'
+];
+
+module.exports = (fromStream, toStream) => {
+	const fromProps = new Set(Object.keys(fromStream).concat(knownProps));
+
+	for (const prop of fromProps) {
+		// Don't overwrite existing properties
+		if (prop in toStream) {
+			continue;
+		}
+
+		toStream[prop] = typeof fromStream[prop] === 'function' ? fromStream[prop].bind(fromStream) : fromStream[prop];
+	}
+};