From 7aeb3f84684325f1d5e0cff276b14aa059c6f6ce Mon Sep 17 00:00:00 2001
From: Nico Jansen <jansennico@gmail.com>
Date: Fri, 11 Feb 2022 08:54:59 +0100
Subject: [PATCH] docs(configuration-file): document async function

See https://github.com/karma-runner/karma/pull/3660
---
 docs/config/01-configuration-file.md | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/docs/config/01-configuration-file.md b/docs/config/01-configuration-file.md
index dff4b6135..dfa0bf1cd 100644
--- a/docs/config/01-configuration-file.md
+++ b/docs/config/01-configuration-file.md
@@ -53,6 +53,20 @@ module.exports = (config) => {
 }
 ```
 
+Alternatively, you can use an `async` function instead (since v6.3).
+
+```javascript
+// karma.conf.js
+module.exports = async (config) => {
+  const karmaConfig = await getKarmaConfig("dev");
+  
+  config.set({
+    ...karmaConfig
+  });
+};
+```
+
+
 ### Customized TypeScript Configuration
 Under the hood Karma uses ts-node to transpile TypeScript to JavaScript. If the resolved `tsconfig.json` has `module` configured as `ES` formats. You might get errors like `SyntaxError: Unexpected token`. This is due that in Node `ES` module formats are not supported. To overcome this issue you need to configure ts-node to use `commonjs` module format.