fix

relay-general/src/pii/processor.rs

@@ -263,13 +263,22 @@ fn apply_regex_to_chunks<'a>(
     // on the chunks, but the `regex` crate does not support that.
 
     let mut search_string = String::new();
+    let mut has_text = false;
     for chunk in &chunks {
         match chunk {
-            Chunk::Text { text } => search_string.push_str(&text.replace('\x00', "")),
+            Chunk::Text { text } => {
+                has_text = true;
+                search_string.push_str(&text.replace('\x00', ""));
+            }
             Chunk::Redaction { .. } => search_string.push('\x00'),
         }
     }
 
+    if !has_text {
+        // Nothing to replace.
+        return chunks;
+    }
+
     // Early exit if this regex does not match and return the original chunks.
     let mut captures_iter = regex.captures_iter(&search_string).peekable();
     if captures_iter.peek().is_none() {