crates/biome_service/src/file_handlers/html.rs (1)

1831-1841: ⚠️ Potential issue | 🟠 Major

Handle all-whitespace tokens to avoid trivia duplication and non-idempotent rewrites.

If value is only whitespace, both read_leading_trivia and read_trailing_trivia can return the full string. That means the reconstructed token can duplicate whitespace (and drift across runs), which is the same class of idempotency bug this PR is fixing.

🩹 Proposed fix

 fn read_trailing_trivia(value: &str) -> Cow<'_, str> {
     let bytes = value.as_bytes();
+    let leading_count = bytes
+        .iter()
+        .take_while(|&&b| matches!(b, b' ' | b'\t' | b'\n' | b'\r'))
+        .count();
+
+    if leading_count == value.len() {
+        return Cow::Borrowed("");
+    }
+
     let count = bytes
         .iter()
         .rev()
         .take_while(|&&b| matches!(b, b' ' | b'\t' | b'\n' | b'\r'))
         .count();

     if count > 0 {
         Cow::Borrowed(&value[value.len() - count..])
     } else {
         Cow::Borrowed("")
     }
 }

🤖 Prompt for AI Agents

Verify each finding against the current code and only fix it if needed.

In `@crates/biome_service/src/file_handlers/html.rs` around lines 1831 - 1841,
read_trailing_trivia currently returns the full string when the input is all
whitespace, which can duplicate whitespace with read_leading_trivia; update
read_trailing_trivia so that if count == value.len() (i.e., the string is all
whitespace) it returns an empty trivia (e.g., Cow::Borrowed("") ) instead of the
whole value, ensuring only one of read_leading_trivia/read_trailing_trivia
yields the full whitespace and preventing duplicated/non-idempotent rewrites.