Correctly report line boundaries when a map contains both folds and wraps

Antonio Scandurra created 4 years ago

This fixes the randomized test failures that were occurring on main.

Change summary

crates/editor/src/display_map.rs          | 10 ++++++++--
crates/editor/src/display_map/fold_map.rs |  2 --
2 files changed, 8 insertions(+), 4 deletions(-)

Detailed changes

crates/editor/src/display_map.rs

@@ -199,7 +199,10 @@ impl DisplaySnapshot {
 
     pub fn prev_line_boundary(&self, mut point: Point) -> (Point, DisplayPoint) {
         loop {
-            point.column = 0;
+            let mut fold_point = point.to_fold_point(&self.folds_snapshot, Bias::Left);
+            *fold_point.column_mut() = 0;
+            point = fold_point.to_buffer_point(&self.folds_snapshot);
+
             let mut display_point = self.point_to_display_point(point, Bias::Left);
             *display_point.column_mut() = 0;
             let next_point = self.display_point_to_point(display_point, Bias::Left);
@@ -212,7 +215,10 @@ impl DisplaySnapshot {
 
     pub fn next_line_boundary(&self, mut point: Point) -> (Point, DisplayPoint) {
         loop {
-            point.column = self.buffer_snapshot.line_len(point.row);
+            let mut fold_point = point.to_fold_point(&self.folds_snapshot, Bias::Right);
+            *fold_point.column_mut() = self.folds_snapshot.line_len(fold_point.row());
+            point = fold_point.to_buffer_point(&self.folds_snapshot);
+
             let mut display_point = self.point_to_display_point(point, Bias::Right);
             *display_point.column_mut() = self.line_len(display_point.row());
             let next_point = self.display_point_to_point(display_point, Bias::Right);

crates/editor/src/display_map/fold_map.rs

@@ -37,7 +37,6 @@ impl FoldPoint {
         &mut self.0.row
     }
 
-    #[cfg(test)]
     pub fn column_mut(&mut self) -> &mut u32 {
         &mut self.0.column
     }
@@ -549,7 +548,6 @@ impl FoldSnapshot {
         FoldOffset(self.transforms.summary().output.bytes)
     }
 
-    #[cfg(test)]
     pub fn line_len(&self, row: u32) -> u32 {
         let line_start = FoldPoint::new(row, 0).to_offset(self).0;
         let line_end = if row >= self.max_point().row() {