From 5d14f56fa9822b18107a5a5efac98dfe9d08f8ce Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Bla=C5=BE=20Hrastnik?= <blaz@mxxn.io>
Date: Thu, 3 Mar 2022 17:41:39 +0900
Subject: [PATCH] Reuse visual_coords_at_pos function in view

---
 helix-core/src/position.rs | 24 ++++++++++++++----------
 helix-term/src/commands.rs |  1 +
 helix-view/src/view.rs     | 14 ++------------
 3 files changed, 17 insertions(+), 22 deletions(-)

diff --git a/helix-core/src/position.rs b/helix-core/src/position.rs
index 93362c77..17908d7a 100644
--- a/helix-core/src/position.rs
+++ b/helix-core/src/position.rs
@@ -1,8 +1,9 @@
+use std::borrow::Cow;
+
 use crate::{
     chars::char_is_line_ending,
-    graphemes::{ensure_grapheme_boundary_prev, RopeGraphemes},
+    graphemes::{ensure_grapheme_boundary_prev, grapheme_width, RopeGraphemes},
     line_ending::line_end_char_index,
-    unicode::width::UnicodeWidthChar,
     RopeSlice,
 };
 
@@ -77,14 +78,17 @@ pub fn visual_coords_at_pos(text: RopeSlice, pos: usize, tab_width: usize) -> Po
 
     let line_start = text.line_to_char(line);
     let pos = ensure_grapheme_boundary_prev(text, pos);
-    let col = text
-        .slice(line_start..pos)
-        .chars()
-        .flat_map(|c| match c {
-            '\t' => Some(tab_width),
-            c => UnicodeWidthChar::width(c),
-        })
-        .sum();
+
+    let mut col = 0;
+
+    for grapheme in RopeGraphemes::new(text.slice(line_start..pos)) {
+        if grapheme == "\t" {
+            col += tab_width;
+        } else {
+            let grapheme = Cow::from(grapheme);
+            col += grapheme_width(&grapheme);
+        }
+    }
 
     Position::new(line, col)
 }
diff --git a/helix-term/src/commands.rs b/helix-term/src/commands.rs
index 39a8df53..8ee05ece 100644
--- a/helix-term/src/commands.rs
+++ b/helix-term/src/commands.rs
@@ -1551,6 +1551,7 @@ fn search_impl(
         };
 
         doc.set_selection(view.id, selection);
+        // TODO: is_cursor_in_view does the same calculation as ensure_cursor_in_view
         if view.is_cursor_in_view(doc, 0) {
             view.ensure_cursor_in_view(doc, scrolloff);
         } else {
diff --git a/helix-view/src/view.rs b/helix-view/src/view.rs
index 6bc9435c..58a9b602 100644
--- a/helix-view/src/view.rs
+++ b/helix-view/src/view.rs
@@ -204,19 +204,9 @@ impl View {
             return None;
         }
 
-        let line_start = text.line_to_char(line);
-        let line_slice = text.slice(line_start..pos);
-        let mut col = 0;
         let tab_width = doc.tab_width();
-
-        for grapheme in RopeGraphemes::new(line_slice) {
-            if grapheme == "\t" {
-                col += tab_width;
-            } else {
-                let grapheme = Cow::from(grapheme);
-                col += grapheme_width(&grapheme);
-            }
-        }
+        // TODO: visual_coords_at_pos also does char_to_line which we ignore, can we reuse the call?
+        let Position { col, .. } = visual_coords_at_pos(text, pos, tab_width);
 
         // It is possible for underflow to occur if the buffer length is larger than the terminal width.
         let row = line.saturating_sub(self.offset.row);