From 91640f9ca5f307a59337a73475ad4603e4e201ad Mon Sep 17 00:00:00 2001
From: jxom <jakemoxey@gmail.com>
Date: Thu, 26 Sep 2024 15:02:01 +1000
Subject: [PATCH] feat: default twoslash to throw on errors

---
 .changeset/rich-eggs-look.md         | 5 +++++
 site/pages/docs/guides/twoslash.mdx  | 1 +
 src/vite/plugins/mdx.ts              | 1 +
 src/vite/plugins/shiki/twoslasher.ts | 1 +
 4 files changed, 8 insertions(+)
 create mode 100644 .changeset/rich-eggs-look.md

diff --git a/.changeset/rich-eggs-look.md b/.changeset/rich-eggs-look.md
new file mode 100644
index 00000000..e27eac00
--- /dev/null
+++ b/.changeset/rich-eggs-look.md
@@ -0,0 +1,5 @@
+---
+"vocs": patch
+---
+
+Defauled Twoslash to throw on syntax errors, and added a `// @noErrors` tag to disable this behavior.
diff --git a/site/pages/docs/guides/twoslash.mdx b/site/pages/docs/guides/twoslash.mdx
index ceab5931..8eebc917 100644
--- a/site/pages/docs/guides/twoslash.mdx
+++ b/site/pages/docs/guides/twoslash.mdx
@@ -206,6 +206,7 @@ Taking this example:
 :::code-group
 
 ```ts [Output] twoslash
+// @allowErrors
 const a = "123"
 a = 132
 ```
diff --git a/src/vite/plugins/mdx.ts b/src/vite/plugins/mdx.ts
index 6e11f4cd..ef36d66c 100644
--- a/src/vite/plugins/mdx.ts
+++ b/src/vite/plugins/mdx.ts
@@ -110,6 +110,7 @@ export const getRehypePlugins = ({
                 twoslashOptions: {
                   ...twoslash,
                   customTags: [
+                    'allowErrors',
                     ...(defaultTwoslashOptions.customTags ?? []),
                     ...(twoslash.customTags ?? []),
                   ],
diff --git a/src/vite/plugins/shiki/twoslasher.ts b/src/vite/plugins/shiki/twoslasher.ts
index 7f29181d..d17b0d0d 100644
--- a/src/vite/plugins/shiki/twoslasher.ts
+++ b/src/vite/plugins/shiki/twoslasher.ts
@@ -14,6 +14,7 @@ export function twoslasher(
     cache.twoslash.set(codeHash, twoslash)
     return twoslash
   } catch (e) {
+    if (!parameters[0].includes('@allowErrors')) throw e
     const error = e as Error
     const lines = parameters[0].split('\n')
     const line = lines.length - 1