From d811e79c160bebc3080bb3fe0eb53e2a3d703d5f Mon Sep 17 00:00:00 2001
From: William G Underwood <42812654+WGUNDERWOOD@users.noreply.github.com>
Date: Tue, 15 Oct 2024 14:36:15 +0100
Subject: [PATCH] Speed up comment finding

---
 src/comments.rs | 13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/src/comments.rs b/src/comments.rs
index f5658ad..65a778c 100644
--- a/src/comments.rs
+++ b/src/comments.rs
@@ -2,12 +2,15 @@
 
 /// Find the location where a comment begins in a line
 pub fn find_comment_index(line: &str) -> Option<usize> {
-    let mut prev_c = ' ';
-    for (i, c) in line.char_indices() {
-        if c == '%' && prev_c != '\\' {
-            return Some(i);
+    // often there is no '%' so check this first
+    if line.contains('%') {
+        let mut prev_c = ' ';
+        for (i, c) in line.char_indices() {
+            if c == '%' && prev_c != '\\' {
+                return Some(i);
+            }
+            prev_c = c;
         }
-        prev_c = c;
     }
     None
 }