From aba1543e9b1d20337ec153a4ee48ad73a08651e3 Mon Sep 17 00:00:00 2001
From: Yoshiya Hinosawa <stibium121@gmail.com>
Date: Tue, 9 Jul 2024 20:34:51 +0900
Subject: [PATCH] docs: document insta snapshot tool in README (#609)

---
 README.md | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/README.md b/README.md
index 463cd452..bbf4a24d 100644
--- a/README.md
+++ b/README.md
@@ -36,6 +36,21 @@ $ deno task build
 $ deno task test
 ```
 
+We use [insta](https://github.com/mitsuhiko/insta) testing tool for taking
+snapshots of the html output. If you change the rednering of html output, or
+change the fixture files for html testing, you need to update snapshot using
+[cargo-insta](https://insta.rs/docs/quickstart/) command.
+
+```
+# update snapshots
+cargo insta test
+
+# review snapshots
+cargo insta review
+```
+
+See [the insta docs](https://insta.rs/docs/quickstart/) for more details.
+
 ## Contributing
 
 - If you are going to work on an issue, mention so in the issue comments