fix(html): handle offset magic-string slice error

vitejs · bluwy · Jan 1, 2024 · Dec 27, 2023 · Dec 27, 2023 · 041d07f6ae8cbf6131c998c86a07cd3232b904ee
commit 041d07f6ae8cbf6131c998c86a07cd3232b904ee
diff --git a/packages/vite/src/node/plugins/html.ts b/packages/vite/src/node/plugins/html.ts
@@ -345,18 +345,13 @@ export function buildHtmlPlugin(config: ResolvedConfig): Plugin {
         const nodeStartWithLeadingWhitespace = (
           node: DefaultTreeAdapterMap['node'],
         ) => {
-          if (node.sourceCodeLocation!.startOffset === 0)
-            return node.sourceCodeLocation!.startOffset
+          const startOffset = node.sourceCodeLocation!.startOffset
+          if (startOffset === 0) return 0
 
           // Gets the offset for the start of the line including the
           // newline trailing the previous node
           const lineStartOffset =
-            node.sourceCodeLocation!.startOffset -
-            node.sourceCodeLocation!.startCol
-          const line = s.slice(
-            Math.max(0, lineStartOffset),
-            node.sourceCodeLocation!.startOffset,
-          )
+            startOffset - node.sourceCodeLocation!.startCol
 
           // <previous-line-node></previous-line-node>
           // <target-node></target-node>
@@ -369,9 +364,16 @@ export function buildHtmlPlugin(config: ResolvedConfig): Plugin {
           //
           // However, if there is content between our target node start and the
           // previous newline, we cannot strip it out without risking content deletion.
-          return line.trim()
-            ? node.sourceCodeLocation!.startOffset
-            : lineStartOffset
+          let isLineEmpty = false
+          try {
+            const line = s.slice(Math.max(0, lineStartOffset), startOffset)
+            isLineEmpty = !line.trim()
+          } catch {
+            // magic-string may throw if there's some content removed in the sliced string,
+            // which we ignore and assume the line is not empty
+          }
+
+          return isLineEmpty ? lineStartOffset : startOffset
         }
 
         // pre-transform

diff --git a/playground/html/vite.config.js b/playground/html/vite.config.js
@@ -39,6 +39,7 @@ export default defineConfig({
         serveFolder: resolve(__dirname, 'serve/folder/index.html'),
         serveBothFile: resolve(__dirname, 'serve/both.html'),
         serveBothFolder: resolve(__dirname, 'serve/both/index.html'),
+        write: resolve(__dirname, 'write.html'),
       },
     },
   },

diff --git a/playground/html/write.html b/playground/html/write.html
@@ -0,0 +1,3 @@
+<!-- prettier-ignore -->
+<html><head><style>div {}
+</style></head><body><script type="module" src="./shared.js"></script></body></html>