Debug DisplaySnapshot and clip_at_line_ends

crates/editor/src/display_map.rs

@@ -776,7 +776,7 @@ pub struct DisplaySnapshot {
     block_snapshot: BlockSnapshot,
     text_highlights: TextHighlights,
     inlay_highlights: InlayHighlights,
-    clip_at_line_ends: bool,
+    pub clip_at_line_ends: bool,
     masked: bool,
     diagnostics_max_severity: DiagnosticSeverity,
     pub(crate) fold_placeholder: FoldPlaceholder,
@@ -1183,8 +1183,10 @@ impl DisplaySnapshot {
 
     pub fn clip_point(&self, point: DisplayPoint, bias: Bias) -> DisplayPoint {
         let mut clipped = self.block_snapshot.clip_point(point.0, bias);
+        println!("  clipped={clipped:?}");
         if self.clip_at_line_ends {
-            clipped = self.clip_at_line_end(DisplayPoint(clipped)).0
+            clipped = self.clip_at_line_end(DisplayPoint(clipped)).0;
+            println!("  clipped(E)={clipped:?}");
         }
         DisplayPoint(clipped)
     }
@@ -1196,6 +1198,11 @@ impl DisplaySnapshot {
     pub fn clip_at_line_end(&self, display_point: DisplayPoint) -> DisplayPoint {
         let mut point = self.display_point_to_point(display_point, Bias::Left);
 
+        println!(
+            "  point.column={}, buffer_line_len={}",
+            point.column,
+            self.buffer_snapshot().line_len(MultiBufferRow(point.row))
+        );
         if point.column != self.buffer_snapshot().line_len(MultiBufferRow(point.row)) {
             return display_point;
         }

crates/vim/src/helix.rs

@@ -263,6 +263,54 @@ impl Vim {
         cx: &mut Context<Self>,
     ) {
         match motion {
+            Motion::EndOfLine { display_lines } => {
+                // In Helix mode, EndOfLine should position cursor ON the last character,
+                // not after it. We need special handling it.
+                self.update_editor(cx, |_, editor, cx| {
+                    let text_layout_details = editor.text_layout_details(window);
+                    editor.change_selections(Default::default(), window, cx, |s| {
+                        s.move_with(|map, selection| {
+                            let goal = selection.goal;
+                            let mut cursor = if selection.is_empty() || selection.reversed {
+                                selection.head()
+                            } else {
+                                movement::left(map, selection.head())
+                            };
+                            println!(">>>");
+                            println!("  clip_at_line_ends={}", map.clip_at_line_ends);
+                            println!("  cursor={cursor:?}");
+
+                            let times = times.unwrap_or(1);
+                            if times > 1 {
+                                cursor =
+                                    map.start_of_relative_buffer_row(cursor, times as isize - 1);
+                            }
+                            let point = if display_lines {
+                                map.clip_point(
+                                    DisplayPoint::new(cursor.row(), map.line_len(cursor.row())),
+                                    Bias::Left,
+                                )
+                            } else {
+                                let nnn = map.next_line_boundary(cursor.to_point(map));
+                                println!("  nnn={nnn:?}");
+                                map.clip_point(
+                                    map.next_line_boundary(cursor.to_point(map)).1,
+                                    Bias::Left,
+                                )
+                            };
+                            // let (point, _goal) = motion
+                            //     .move_point(map, cursor, goal, times, &text_layout_details)
+                            //     .unwrap_or((cursor, goal));
+                            println!("  point={point:?}");
+                            println!("<<<");
+
+                            // Move left by one character to position on the last character
+                            let adjusted_point = movement::saturating_left(map, point);
+                            selection.collapse_to(adjusted_point, SelectionGoal::None)
+                        })
+                    });
+                });
+            }
             Motion::NextWordStart { ignore_punctuation } => {
                 self.helix_find_range_forward(times, window, cx, |left, right, classifier| {
                     let left_kind = classifier.kind_with(left, ignore_punctuation);
@@ -1493,4 +1541,59 @@ mod test {
             Mode::Insert,
         );
     }
+
+    #[gpui::test]
+    async fn test_g_l_end_of_line(cx: &mut gpui::TestAppContext) {
+        let mut cx = VimTestContext::new(cx, true).await;
+        cx.enable_helix();
+
+        // Test g l moves to last character, not after it
+        cx.set_state("hello ˇworld!", Mode::HelixNormal);
+        cx.simulate_keystrokes("g l");
+        cx.assert_state("hello worldˇ!", Mode::HelixNormal);
+
+        // Test with Chinese characters, test if work with UTF-8?
+        cx.set_state("ˇ你好世界", Mode::HelixNormal);
+        cx.simulate_keystrokes("g l");
+        cx.assert_state("你好世ˇ界", Mode::HelixNormal);
+
+        // Test with end of line
+        cx.set_state("endˇ", Mode::HelixNormal);
+        cx.simulate_keystrokes("g l");
+        cx.assert_state("enˇd", Mode::HelixNormal);
+
+        // Test with empty line
+        cx.set_state(
+            indoc! {"
+                hello
+                ˇ
+                world"},
+            Mode::HelixNormal,
+        );
+        cx.simulate_keystrokes("g l");
+        cx.assert_state(
+            indoc! {"
+                hello
+                ˇ
+                world"},
+            Mode::HelixNormal,
+        );
+
+        // Test with multiple lines
+        cx.set_state(
+            indoc! {"
+                ˇfirst line
+                second line
+                third line"},
+            Mode::HelixNormal,
+        );
+        cx.simulate_keystrokes("g l");
+        cx.assert_state(
+            indoc! {"
+                first linˇe
+                second line
+                third line"},
+            Mode::HelixNormal,
+        );
+    }
 }