fix(transformers): also remove extra newline token, fix #915

Author: antfu

docs/packages/transformers.md

@@ -177,6 +177,13 @@ console.log('Highlighted')
 console.log('Highlighted')
 console.log('Not highlighted')
 ```
+
+```ts
+console.log('Not highlighted')
+// [\!code highlight:1]
+console.log('Highlighted')
+console.log('Not highlighted')
+```
 ````
 
 Renders:
@@ -188,6 +195,13 @@ console.log('Highlighted')
 console.log('Not highlighted')
 ```
 
+```ts
+console.log('Not highlighted')
+// [!code highlight:1]
+console.log('Highlighted')
+console.log('Not highlighted')
+```
+
 ---
 
 ### `transformerNotationWordHighlight`

packages/transformers/src/shared/notation-transformer.ts

@@ -95,8 +95,14 @@ export function createCommentNotationTransformer(
         }
       }
 
-      for (const line of linesToRemove)
-        code.children.splice(code.children.indexOf(line), 1)
+      for (const line of linesToRemove) {
+        const index = code.children.indexOf(line)
+        const nextLine = code.children[index + 1]
+        let removeLength = 1
+        if (nextLine?.type === 'text' && nextLine?.value === '\n')
+          removeLength = 2
+        code.children.splice(index, removeLength)
+      }
     },
   }
 }