Fix cursor line

parley/src/editor/layout.rs

@@ -387,10 +387,11 @@ impl<T: TextStorage> TextLayout<T> {
     /// This is not meaningful until [`Self::rebuild`] has been called.
     // TODO: This is too simplistic. See https://raphlinus.github.io/text/2020/10/26/text-layout.html#shaping-cluster
     // for example. This would break in a `fi` ligature
-    pub fn cursor_line_for_text_position(&self, text_pos: usize) -> Line {
+    pub fn cursor_line_for_text_position(&self, text_pos: usize) -> Option<Line> {
         let from_position = self.cursor_for_text_position(text_pos);
 
-        let line = from_position.path.line(&self.layout).unwrap();
+        // TODO: fix in case there is no text
+        let line = from_position.path.line(&self.layout)?;
         let line_metrics = line.metrics();
 
         let baseline = line_metrics.baseline + line_metrics.descent;
@@ -399,7 +400,7 @@ impl<T: TextStorage> TextLayout<T> {
             from_position.offset as f64,
             (baseline - line_metrics.size()) as f64,
         );
-        Line::new(p1, p2)
+        Some(Line::new(p1, p2))
     }
 
     /// Returns the [`Link`] at the provided point (relative to the layout's origin) if one exists.

parley/src/editor/selection.rs

@@ -30,7 +30,7 @@ pub struct TextWithSelection<T: Selectable> {
     needs_selection_update: bool,
     selecting_with_mouse: bool,
     // TODO: Cache cursor line, selection boxes
-    cursor_line: Option<Line>,
+    // cursor_line: Option<Line>,
 }
 
 impl<T: Selectable> TextWithSelection<T> {
@@ -40,7 +40,7 @@ impl<T: Selectable> TextWithSelection<T> {
             selection: None,
             needs_selection_update: false,
             selecting_with_mouse: false,
-            cursor_line: None,
+            // cursor_line: None,
             highlight_brush: TextBrush::Highlight {
                 text: Color::WHITE.into(),
                 fill: Color::LIGHT_BLUE.into(),
@@ -59,7 +59,12 @@ impl<T: Selectable> TextWithSelection<T> {
     }
 
     pub fn get_cursor_line(&self) -> Option<Line> {
-        self.cursor_line
+        // self.cursor_line
+        if let Some(selection) = self.selection {
+            self.layout.cursor_line_for_text_position(selection.active)
+        } else {
+            None
+        }
     }
 
     pub fn pointer_down(