ui: Highlight line ranges in the preview

1 files changed, 19 insertions, 10 deletions

diff --git a/helix-term/src/ui/picker.rs b/helix-term/src/ui/picker.rs
index ecf9d528..036b41c8 100644
--- a/helix-term/src/ui/picker.rs
+++ b/helix-term/src/ui/picker.rs
@@ -26,7 +26,7 @@ use helix_view::{
 pub const MIN_SCREEN_WIDTH_FOR_PREVIEW: u16 = 80;
 
 /// File path and line number (used to align and highlight a line)
-type FileLocation = (PathBuf, Option<usize>);
+type FileLocation = (PathBuf, Option<(usize, usize)>);
 
 pub struct FilePicker<T> {
     picker: Picker<T>,
@@ -113,14 +113,17 @@ impl<T: 'static> Component for FilePicker<T> {
 
         block.render(preview_area, surface);
 
-        if let Some((doc, line)) = self.current_file(cx.editor).and_then(|(path, line)| {
+        if let Some((doc, line)) = self.current_file(cx.editor).and_then(|(path, range)| {
             cx.editor
                 .document_by_path(&path)
                 .or_else(|| self.preview_cache.get(&path))
-                .zip(Some(line))
+                .zip(Some(range))
         }) {
             // align to middle
-            let first_line = line.unwrap_or(0).saturating_sub(inner.height as usize / 2);
+            let first_line = line
+                .map(|(start, _)| start)
+                .unwrap_or(0)
+                .saturating_sub(inner.height as usize / 2);
             let offset = Position::new(first_line, 0);
 
             let highlights = EditorView::doc_syntax_highlights(
@@ -140,12 +143,18 @@ impl<T: 'static> Component for FilePicker<T> {
             );
 
             // highlight the line
-            if let Some(line) = line {
-                for x in inner.left()..inner.right() {
-                    surface
-                        .get_mut(x, inner.y + line.saturating_sub(first_line) as u16)
-                        .set_style(cx.editor.theme.get("ui.selection"));
-                }
+            if let Some((start, end)) = line {
+                let offset = start.saturating_sub(first_line) as u16;
+                surface.set_style(
+                    Rect::new(
+                        inner.x,
+                        inner.y + offset,
+                        inner.width,
+                        (end.saturating_sub(start) as u16 + 1)
+                            .min(inner.height.saturating_sub(offset)),
+                    ),
+                    cx.editor.theme.get("ui.selection"),
+                );
             }
         }
     }