From f217cb29b603593e0dfef300fac668aa5f0141a5 Mon Sep 17 00:00:00 2001
From: Florian Lefebvre <contact@florian-lefebvre.dev>
Date: Thu, 5 Sep 2024 15:54:48 +0200
Subject: [PATCH] feat(create-astro): ts-check comment

---
 .changeset/nasty-dogs-sort.md                   |  5 +++++
 packages/create-astro/src/actions/typescript.ts | 15 +++++++++++++++
 2 files changed, 20 insertions(+)
 create mode 100644 .changeset/nasty-dogs-sort.md

diff --git a/.changeset/nasty-dogs-sort.md b/.changeset/nasty-dogs-sort.md
new file mode 100644
index 000000000000..225012a70036
--- /dev/null
+++ b/.changeset/nasty-dogs-sort.md
@@ -0,0 +1,5 @@
+---
+'create-astro': patch
+---
+
+Updates the default Astro config with `// @ts-check` if the Typescript preset is `strict` or `strictest`
diff --git a/packages/create-astro/src/actions/typescript.ts b/packages/create-astro/src/actions/typescript.ts
index c0034fe4f83a..169aef7089fe 100644
--- a/packages/create-astro/src/actions/typescript.ts
+++ b/packages/create-astro/src/actions/typescript.ts
@@ -140,6 +140,21 @@ const FILES_TO_UPDATE = {
 			}
 		}
 	},
+	'astro.config.mjs': async (file: string, options: { value: string }) => {
+		if (!(options.value === 'strict' || options.value === 'strictest')) {
+			return;
+		}
+
+		try {
+			let data = await readFile(file, { encoding: 'utf-8' });
+			data = `// @ts-check\n${data}`;
+			await writeFile(file, data, { encoding: 'utf-8' });
+		} catch (err) {
+			// if there's no astro.config.mjs (which is very unlikely), then do nothing
+			if (err && (err as any).code === 'ENOENT') return;
+			if (err instanceof Error) throw new Error(err.message);
+		}
+	},
 };
 
 export async function setupTypeScript(value: string, ctx: PickedTypeScriptContext) {