Fix tests

Author: ehmicky

ava.config.js

@@ -1,6 +1,9 @@
 'use strict'
 
 export default {
+  babel: false,
+  compileEnhancements: false,
+  files: ['dist/test'],
   // Tests are setting listeners on `process` and stubbing global
   // `process.exit`, `console`, `setTimeout` and `Error.prepareStackTrace`,
   // so we cannot parallelize them.

gulp/files.json

@@ -10,6 +10,6 @@
     "examples/*.js",
     "examples/**/*.js"
   ],
-  "TRANSPILED": ["src", "test"],
+  "TRANSPILED": ["src", "test", "helpers"],
   "MARKDOWN": ["*.md"]
 }