From 7a0ce2dfea6c34d5d52c00dca004f1d5455b0e45 Mon Sep 17 00:00:00 2001
From: Rich Harris <rich.harris@vercel.com>
Date: Mon, 17 Jun 2024 07:14:36 -0700
Subject: [PATCH] fix: correctly process empty lines in message markdown
 (#12057)

---
 .changeset/loud-penguins-unite.md                 | 5 +++++
 packages/svelte/scripts/process-messages/index.js | 2 +-
 packages/svelte/src/internal/client/errors.js     | 4 ++--
 3 files changed, 8 insertions(+), 3 deletions(-)
 create mode 100644 .changeset/loud-penguins-unite.md

diff --git a/.changeset/loud-penguins-unite.md b/.changeset/loud-penguins-unite.md
new file mode 100644
index 0000000000..36e4375155
--- /dev/null
+++ b/.changeset/loud-penguins-unite.md
@@ -0,0 +1,5 @@
+---
+'svelte': patch
+---
+
+fix: correctly process empty lines in messages
diff --git a/packages/svelte/scripts/process-messages/index.js b/packages/svelte/scripts/process-messages/index.js
index d88e5c728e..71a979d516 100644
--- a/packages/svelte/scripts/process-messages/index.js
+++ b/packages/svelte/scripts/process-messages/index.js
@@ -43,7 +43,7 @@ for (const category of fs.readdirSync('messages')) {
 
 			seen.add(code);
 			messages[category][code] = {
-				messages: sections.map((section) => section.replace(/^> /gm, '')),
+				messages: sections.map((section) => section.replace(/^> /gm, '').replace(/^>\n/gm, '\n')),
 				details
 			};
 		}
diff --git a/packages/svelte/src/internal/client/errors.js b/packages/svelte/src/internal/client/errors.js
index 981f40a218..232cc2eeee 100644
--- a/packages/svelte/src/internal/client/errors.js
+++ b/packages/svelte/src/internal/client/errors.js
@@ -280,13 +280,13 @@ export function state_prototype_fixed() {
 
 /**
  * Unsafe mutations during Svelte's render or derived phase are not permitted in runes mode. This can lead to unexpected errors and possibly cause infinite loops.
- * >
+ * 
  * If the object is not meant to be reactive, declare it without `$state`
  * @returns {never}
  */
 export function state_unsafe_mutation() {
 	if (DEV) {
-		const error = new Error(`${"state_unsafe_mutation"}\n${"Unsafe mutations during Svelte's render or derived phase are not permitted in runes mode. This can lead to unexpected errors and possibly cause infinite loops.\n>\nIf the object is not meant to be reactive, declare it without `$state`"}`);
+		const error = new Error(`${"state_unsafe_mutation"}\n${"Unsafe mutations during Svelte's render or derived phase are not permitted in runes mode. This can lead to unexpected errors and possibly cause infinite loops.\n\nIf the object is not meant to be reactive, declare it without `$state`"}`);
 
 		error.name = 'Svelte error';
 		throw error;