From ab8a795b41a1e5d25bc9cbd48e85d86624b40fe3 Mon Sep 17 00:00:00 2001
From: Aidan Montare <aidan@aidanmontare.net>
Date: Tue, 3 Jun 2025 11:50:28 -0600
Subject: [PATCH] log highlight time as total time spent on
 syntax_highlighter.advance

...instead of time taken to create the Highlighter.

This still outputs INFO messages at each cursor move, which seems
excessive. Would it make sense to only output when a file is first
opened?
---
 helix-core/src/syntax.rs      | 5 +----
 helix-term/src/ui/document.rs | 6 ++++++
 2 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/helix-core/src/syntax.rs b/helix-core/src/syntax.rs
index 5415e52c4..ccfb00808 100644
--- a/helix-core/src/syntax.rs
+++ b/helix-core/src/syntax.rs
@@ -500,10 +500,7 @@ impl Syntax {
         loader: &'a Loader,
         range: impl RangeBounds<u32>,
     ) -> Highlighter<'a> {
-        let highlight_time = Instant::now();
-        let ret = Highlighter::new(&self.inner, source, loader, range);
-        log::info!("tree-sitter: creating highlighter took: {} us", highlight_time.elapsed().as_micros());
-        ret
+        Highlighter::new(&self.inner, source, loader, range)
     }
 
     pub fn query_iter<'a, QueryLoader, LayerState, Range>(
diff --git a/helix-term/src/ui/document.rs b/helix-term/src/ui/document.rs
index 524d829c4..38ad7ebb9 100644
--- a/helix-term/src/ui/document.rs
+++ b/helix-term/src/ui/document.rs
@@ -1,4 +1,5 @@
 use std::cmp::min;
+use std::time::{Duration, Instant};
 
 use helix_core::doc_formatter::{DocumentFormatter, GraphemeSource, TextFormat};
 use helix_core::graphemes::Grapheme;
@@ -90,6 +91,7 @@ pub fn render_text(
     let mut is_in_indent_area = true;
     let mut last_line_indent_level = 0;
     let mut reached_view_top = false;
+    let mut total_highlight_time = Duration::new(0, 0);
 
     loop {
         let Some(mut grapheme) = formatter.next() else {
@@ -132,9 +134,11 @@ pub fn render_text(
         }
 
         // acquire the correct grapheme style
+        let highlight_time = Instant::now();
         while grapheme.char_idx >= syntax_highlighter.pos {
             syntax_highlighter.advance();
         }
+        total_highlight_time += highlight_time.elapsed();
         while grapheme.char_idx >= overlay_highlighter.pos {
             overlay_highlighter.advance();
         }
@@ -168,6 +172,8 @@ pub fn render_text(
         last_line_end = grapheme.visual_pos.col + grapheme_width;
     }
 
+    log::info!("tree-sitter highlight time: {} us", total_highlight_time.as_micros());
+
     renderer.draw_indent_guides(last_line_indent_level, last_line_pos.visual_line);
     decorations.render_virtual_lines(renderer, last_line_pos, last_line_end)
 }