Fix scrolling (#650)

* fix(grid): scroll up on empty line

* fix(grid): line wrapping while scrolling

* style(grid): fix names

* docs(changelog): document fix

CHANGELOG.md

@@ -19,6 +19,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/)
 * New pane UI: draw pane frames - can be disabled with ctrl-p + z, or through configuration (https://github.com/zellij-org/zellij/pull/643)
 * Terminal compatibility: support changing index colors through OSC 4 and similar (https://github.com/zellij-org/zellij/pull/646)
 * Fix various shells (eg. nushell) unexpectedly exiting when the user presses ctrl-c (https://github.com/zellij-org/zellij/pull/648)
+* Fix line wrapping while scrolling (https://github.com/zellij-org/zellij/pull/650)
 
 ## [0.15.0] - 2021-07-19
 * Kill children properly (https://github.com/zellij-org/zellij/pull/601)

src/tests/fixtures/scrolling

@@ -0,0 +1,20 @@
+
line 1aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+
line 2aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+
line 3aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+
line 4aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+
line 5aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+
line 6aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+
line 7aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+
line 8aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+
line 9aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+
line 10aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+
line 11aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+
line 12aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+
line 13aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+
line 14aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+
line 15aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+
line 16aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+
line 17aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+
line 18aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+
line 19aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+
line 20aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa

zellij-server/src/panes/grid.rs

@@ -42,7 +42,7 @@ fn get_top_non_canonical_rows(rows: &mut Vec<Row>) -> Vec<Row> {
     }
 }
 
-fn get_bottom_canonical_row_and_wraps(rows: &mut VecDeque<Row>) -> Vec<Row> {
+fn get_lines_above_bottom_canonical_row_and_wraps(rows: &mut VecDeque<Row>) -> Vec<Row> {
     let mut index_of_last_non_canonical_row = None;
     for (i, row) in rows.iter().enumerate().rev() {
         index_of_last_non_canonical_row = Some(i);
@@ -58,100 +58,157 @@ fn get_bottom_canonical_row_and_wraps(rows: &mut VecDeque<Row>) -> Vec<Row> {
     }
 }
 
-fn transfer_rows_down(
+fn get_viewport_bottom_canonical_row_and_wraps(viewport: &mut Vec<Row>) -> Vec<Row> {
-    source: &mut VecDeque<Row>,
+    let mut index_of_last_non_canonical_row = None;
-    destination: &mut Vec<Row>,
+    for (i, row) in viewport.iter().enumerate().rev() {
+        index_of_last_non_canonical_row = Some(i);
+        if row.is_canonical {
+            break;
+        }
+    }
+    match index_of_last_non_canonical_row {
+        Some(index_of_last_non_canonical_row) => {
+            viewport.drain(index_of_last_non_canonical_row..).collect()
+        }
+        None => vec![],
+    }
+}
+
+fn get_top_canonical_row_and_wraps(rows: &mut Vec<Row>) -> Vec<Row> {
+    let mut index_of_first_non_canonical_row = None;
+    let mut end_index_of_first_canonical_line = None;
+    for (i, row) in rows.iter().enumerate() {
+        if row.is_canonical && end_index_of_first_canonical_line.is_none() {
+            index_of_first_non_canonical_row = Some(i);
+            end_index_of_first_canonical_line = Some(i);
+            continue;
+        }
+        if row.is_canonical && end_index_of_first_canonical_line.is_some() {
+            break;
+        }
+        if index_of_first_non_canonical_row.is_some() {
+            end_index_of_first_canonical_line = Some(i);
+            continue;
+        }
+    }
+    match (
+        index_of_first_non_canonical_row,
+        end_index_of_first_canonical_line,
+    ) {
+        (Some(first_index), Some(last_index)) => rows.drain(first_index..=last_index).collect(),
+        (Some(first_index), None) => rows.drain(first_index..).collect(),
+        _ => vec![],
+    }
+}
+
+fn transfer_rows_from_lines_above_to_viewport(
+    lines_above: &mut VecDeque<Row>,
+    viewport: &mut Vec<Row>,
     count: usize,
-    max_src_width: Option<usize>,
+    max_viewport_width: usize,
-    max_dst_width: Option<usize>,
 ) {
     let mut next_lines: Vec<Row> = vec![];
-    let mut lines_added_to_destination: isize = 0;
+    let mut lines_added_to_viewport: isize = 0;
     loop {
-        if lines_added_to_destination as usize == count {
+        if lines_added_to_viewport as usize == count {
             break;
         }
         if next_lines.is_empty() {
-            match source.pop_back() {
+            match lines_above.pop_back() {
                 Some(next_line) => {
-                    let mut top_non_canonical_rows_in_dst = get_top_non_canonical_rows(destination);
+                    let mut top_non_canonical_rows_in_dst = get_top_non_canonical_rows(viewport);
-                    lines_added_to_destination -= top_non_canonical_rows_in_dst.len() as isize;
+                    lines_added_to_viewport -= top_non_canonical_rows_in_dst.len() as isize;
                     next_lines.push(next_line);
                     next_lines.append(&mut top_non_canonical_rows_in_dst);
-                    next_lines = match max_dst_width {
+                    next_lines = Row::from_rows(next_lines, max_viewport_width)
-                        Some(max_row_width) => Row::from_rows(next_lines, max_row_width)
+                        .split_to_rows_of_length(max_viewport_width);
-                            .split_to_rows_of_length(max_row_width),
-                        None => vec![Row::from_rows(next_lines, 0)],
-                    };
                     if next_lines.is_empty() {
-                        // no more lines at source, the line we popped was probably empty
+                        // no more lines at lines_above, the line we popped was probably empty
                         break;
                     }
                 }
                 None => break, // no more rows
             }
         }
-        destination.insert(0, next_lines.pop().unwrap());
+        viewport.insert(0, next_lines.pop().unwrap());
-        lines_added_to_destination += 1;
+        lines_added_to_viewport += 1;
     }
     if !next_lines.is_empty() {
-        match max_src_width {
-            Some(max_row_width) => {
-                let excess_rows = Row::from_rows(next_lines, max_row_width)
-                    .split_to_rows_of_length(max_row_width);
-                source.extend(excess_rows);
-            }
-            None => {
         let excess_row = Row::from_rows(next_lines, 0);
-                bounded_push(source, excess_row);
+        bounded_push(lines_above, excess_row);
-            }
-        }
     }
 }
 
-fn transfer_rows_up(
+fn transfer_rows_from_viewport_to_lines_above(
-    source: &mut Vec<Row>,
+    viewport: &mut Vec<Row>,
-    destination: &mut VecDeque<Row>,
+    lines_above: &mut VecDeque<Row>,
     count: usize,
-    max_src_width: Option<usize>,
+    max_viewport_width: usize,
-    max_dst_width: Option<usize>,
 ) {
     let mut next_lines: Vec<Row> = vec![];
     for _ in 0..count {
         if next_lines.is_empty() {
-            if !source.is_empty() {
+            if !viewport.is_empty() {
-                let next_line = source.remove(0);
+                let next_line = viewport.remove(0);
                 if !next_line.is_canonical {
                     let mut bottom_canonical_row_and_wraps_in_dst =
-                        get_bottom_canonical_row_and_wraps(destination);
+                        get_lines_above_bottom_canonical_row_and_wraps(lines_above);
                     next_lines.append(&mut bottom_canonical_row_and_wraps_in_dst);
                 }
                 next_lines.push(next_line);
-                next_lines = match max_dst_width {
+                next_lines = vec![Row::from_rows(next_lines, 0)];
-                    Some(max_row_width) => Row::from_rows(next_lines, max_row_width)
-                        .split_to_rows_of_length(max_row_width),
-                    None => vec![Row::from_rows(next_lines, 0)],
-                };
             } else {
                 break; // no more rows
             }
         }
-        bounded_push(destination, next_lines.remove(0));
+        bounded_push(lines_above, next_lines.remove(0));
     }
     if !next_lines.is_empty() {
-        match max_src_width {
+        let excess_rows = Row::from_rows(next_lines, max_viewport_width)
-            Some(max_row_width) => {
+            .split_to_rows_of_length(max_viewport_width);
-                let excess_rows = Row::from_rows(next_lines, max_row_width)
-                    .split_to_rows_of_length(max_row_width);
         for row in excess_rows {
-                    source.insert(0, row);
+            viewport.insert(0, row);
         }
     }
-            None => {
+}
+
+fn transfer_rows_from_lines_below_to_viewport(
+    lines_below: &mut Vec<Row>,
+    viewport: &mut Vec<Row>,
+    count: usize,
+    max_viewport_width: usize,
+) {
+    let mut next_lines: Vec<Row> = vec![];
+    for _ in 0..count {
+        let mut lines_pulled_from_viewport = 0;
+        if next_lines.is_empty() {
+            if !lines_below.is_empty() {
+                let mut top_non_canonical_rows_in_lines_below =
+                    get_top_non_canonical_rows(lines_below);
+                if !top_non_canonical_rows_in_lines_below.is_empty() {
+                    let mut canonical_line = get_viewport_bottom_canonical_row_and_wraps(viewport);
+                    lines_pulled_from_viewport += canonical_line.len();
+                    canonical_line.append(&mut top_non_canonical_rows_in_lines_below);
+                    next_lines = Row::from_rows(canonical_line, max_viewport_width)
+                        .split_to_rows_of_length(max_viewport_width);
+                } else {
+                    let canonical_row = get_top_canonical_row_and_wraps(lines_below);
+                    next_lines = Row::from_rows(canonical_row, max_viewport_width)
+                        .split_to_rows_of_length(max_viewport_width);
+                }
+            } else {
+                break; // no more rows
+            }
+        }
+        for _ in 0..(lines_pulled_from_viewport + 1) {
+            if !next_lines.is_empty() {
+                viewport.push(next_lines.remove(0));
+            }
+        }
+    }
+    if !next_lines.is_empty() {
         let excess_row = Row::from_rows(next_lines, 0);
-                source.insert(0, excess_row);
+        lines_below.insert(0, excess_row);
-            }
-        }
     }
 }
 
@@ -481,12 +538,11 @@ impl Grid {
             let line_to_push_down = self.viewport.pop().unwrap();
             self.lines_below.insert(0, line_to_push_down);
 
-            transfer_rows_down(
+            transfer_rows_from_lines_above_to_viewport(
                 &mut self.lines_above,
                 &mut self.viewport,
                 1,
-                None,
+                self.width,
-                Some(self.width),
             );
 
             self.selection.move_down(1);
@@ -503,8 +559,14 @@ impl Grid {
                 last_line_above.append(&mut line_to_push_up.columns);
                 bounded_push(&mut self.lines_above, last_line_above);
             }
-            let line_to_insert_at_viewport_bottom = self.lines_below.remove(0);
+
-            self.viewport.push(line_to_insert_at_viewport_bottom);
+            transfer_rows_from_lines_below_to_viewport(
+                &mut self.lines_below,
+                &mut self.viewport,
+                1,
+                self.width,
+            );
+
             self.selection.move_up(1);
             self.output_buffer.update_all_lines();
         }
@@ -593,12 +655,12 @@ impl Grid {
             match current_viewport_row_count.cmp(&self.height) {
                 Ordering::Less => {
                     let row_count_to_transfer = self.height - current_viewport_row_count;
-                    transfer_rows_down(
+
+                    transfer_rows_from_lines_above_to_viewport(
                         &mut self.lines_above,
                         &mut self.viewport,
                         row_count_to_transfer,
-                        None,
+                        new_columns,
-                        Some(new_columns),
                     );
                     let rows_pulled = self.viewport.len() - current_viewport_row_count;
                     new_cursor_y += rows_pulled;
@@ -610,12 +672,11 @@ impl Grid {
                     } else {
                         new_cursor_y -= row_count_to_transfer;
                     }
-                    transfer_rows_up(
+                    transfer_rows_from_viewport_to_lines_above(
                         &mut self.viewport,
                         &mut self.lines_above,
                         row_count_to_transfer,
-                        Some(new_columns),
+                        new_columns,
-                        None,
                     );
                 }
                 Ordering::Equal => {}
@@ -628,12 +689,11 @@ impl Grid {
             match current_viewport_row_count.cmp(&new_rows) {
                 Ordering::Less => {
                     let row_count_to_transfer = new_rows - current_viewport_row_count;
-                    transfer_rows_down(
+                    transfer_rows_from_lines_above_to_viewport(
                         &mut self.lines_above,
                         &mut self.viewport,
                         row_count_to_transfer,
-                        None,
+                        new_columns,
-                        Some(new_columns),
                     );
                     let rows_pulled = self.viewport.len() - current_viewport_row_count;
                     self.cursor.y += rows_pulled;
@@ -645,12 +705,11 @@ impl Grid {
                     } else {
                         self.cursor.y -= row_count_to_transfer;
                     }
-                    transfer_rows_up(
+                    transfer_rows_from_viewport_to_lines_above(
                         &mut self.viewport,
                         &mut self.lines_above,
                         row_count_to_transfer,
-                        Some(new_columns),
+                        new_columns,
-                        None,
                     );
                 }
                 Ordering::Equal => {}
@@ -794,12 +853,11 @@ impl Grid {
         }
         if self.cursor.y == self.height - 1 {
             let row_count_to_transfer = 1;
-            transfer_rows_up(
+            transfer_rows_from_viewport_to_lines_above(
                 &mut self.viewport,
                 &mut self.lines_above,
                 row_count_to_transfer,
-                Some(self.width),
+                self.width,
-                None,
             );
             self.selection.move_up(1);
             self.output_buffer.update_all_lines();
@@ -869,12 +927,11 @@ impl Grid {
             self.cursor.x = 0;
             if self.cursor.y == self.height - 1 {
                 let row_count_to_transfer = 1;
-                transfer_rows_up(
+                transfer_rows_from_viewport_to_lines_above(
                     &mut self.viewport,
                     &mut self.lines_above,
                     row_count_to_transfer,
-                    Some(self.width),
+                    self.width,
-                    None,
                 );
                 let wrapped_row = Row::new(self.width);
                 self.viewport.push(wrapped_row);
@@ -2165,6 +2222,9 @@ impl Row {
         if !parts.is_empty() && self.is_canonical {
             parts.get_mut(0).unwrap().is_canonical = true;
         }
+        if parts.is_empty() {
+            parts.push(self.clone());
+        }
         parts
     }
 }

zellij-server/src/panes/unit/grid_tests.rs

@@ -608,9 +608,9 @@ fn copy_selected_text_from_lines_below() {
 
     grid.move_viewport_up(40);
 
-    grid.start_selection(&Position::new(35, 6));
+    grid.start_selection(&Position::new(63, 6));
     // check for widechar, 📦 occupies columns 34, 35, and gets selected even if only the first column is selected
-    grid.end_selection(Some(&Position::new(37, 35)));
+    grid.end_selection(Some(&Position::new(65, 35)));
     let text = grid.get_selected_text();
     assert_eq!(
         text.unwrap(),
@@ -907,3 +907,95 @@ pub fn exa_plus_omf_theme() {
     }
     assert_snapshot!(format!("{:?}", grid));
 }
+
+#[test]
+pub fn scroll_up() {
+    let mut vte_parser = vte::Parser::new();
+    let mut grid = Grid::new(10, 50, Palette::default());
+    let fixture_name = "scrolling";
+    let content = read_fixture(fixture_name);
+    for byte in content {
+        vte_parser.advance(&mut grid, byte);
+    }
+    grid.scroll_up_one_line();
+    assert_snapshot!(format!("{:?}", grid));
+}
+
+#[test]
+pub fn scroll_down() {
+    let mut vte_parser = vte::Parser::new();
+    let mut grid = Grid::new(10, 50, Palette::default());
+    let fixture_name = "scrolling";
+    let content = read_fixture(fixture_name);
+    for byte in content {
+        vte_parser.advance(&mut grid, byte);
+    }
+    grid.scroll_up_one_line();
+    grid.scroll_down_one_line();
+    assert_snapshot!(format!("{:?}", grid));
+}
+
+#[test]
+pub fn scroll_up_with_line_wraps() {
+    let mut vte_parser = vte::Parser::new();
+    let mut grid = Grid::new(10, 25, Palette::default());
+    let fixture_name = "scrolling";
+    let content = read_fixture(fixture_name);
+    for byte in content {
+        vte_parser.advance(&mut grid, byte);
+    }
+    grid.scroll_up_one_line();
+    assert_snapshot!(format!("{:?}", grid));
+}
+
+#[test]
+pub fn scroll_down_with_line_wraps() {
+    let mut vte_parser = vte::Parser::new();
+    let mut grid = Grid::new(10, 25, Palette::default());
+    let fixture_name = "scrolling";
+    let content = read_fixture(fixture_name);
+    for byte in content {
+        vte_parser.advance(&mut grid, byte);
+    }
+    grid.scroll_up_one_line();
+    grid.scroll_down_one_line();
+    assert_snapshot!(format!("{:?}", grid));
+}
+
+#[test]
+pub fn scroll_up_decrease_width_and_scroll_down() {
+    let mut vte_parser = vte::Parser::new();
+    let mut grid = Grid::new(10, 50, Palette::default());
+    let fixture_name = "scrolling";
+    let content = read_fixture(fixture_name);
+    for byte in content {
+        vte_parser.advance(&mut grid, byte);
+    }
+    for _ in 0..10 {
+        grid.scroll_up_one_line();
+    }
+    grid.change_size(10, 25);
+    for _ in 0..10 {
+        grid.scroll_down_one_line();
+    }
+    assert_snapshot!(format!("{:?}", grid));
+}
+
+#[test]
+pub fn scroll_up_increase_width_and_scroll_down() {
+    let mut vte_parser = vte::Parser::new();
+    let mut grid = Grid::new(10, 25, Palette::default());
+    let fixture_name = "scrolling";
+    let content = read_fixture(fixture_name);
+    for byte in content {
+        vte_parser.advance(&mut grid, byte);
+    }
+    for _ in 0..10 {
+        grid.scroll_up_one_line();
+    }
+    grid.change_size(10, 50);
+    for _ in 0..10 {
+        grid.scroll_down_one_line();
+    }
+    assert_snapshot!(format!("{:?}", grid));
+}

zellij-server/src/panes/unit/snapshots/zellij_server__panes__grid__grid_tests__scroll_down.snap

@@ -0,0 +1,16 @@
+---
+source: zellij-server/src/panes/./unit/grid_tests.rs
+expression: "format!(\"{:?}\", grid)"
+
+---
+00 (C): line 11aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+01 (C): line 12aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+02 (C): line 13aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+03 (C): line 14aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+04 (C): line 15aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+05 (C): line 16aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+06 (C): line 17aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+07 (C): line 18aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+08 (C): line 19aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+09 (C): line 20aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+

zellij-server/src/panes/unit/snapshots/zellij_server__panes__grid__grid_tests__scroll_down_with_line_wraps.snap

@@ -0,0 +1,16 @@
+---
+source: zellij-server/src/panes/./unit/grid_tests.rs
+expression: "format!(\"{:?}\", grid)"
+
+---
+00 (C): line 16aaaaaaaaaaaaaaaaaa
+01 (W): aaaaaaaaaaaaaaaaaaaaaaaa
+02 (C): line 17aaaaaaaaaaaaaaaaaa
+03 (W): aaaaaaaaaaaaaaaaaaaaaaaa
+04 (C): line 18aaaaaaaaaaaaaaaaaa
+05 (W): aaaaaaaaaaaaaaaaaaaaaaaa
+06 (C): line 19aaaaaaaaaaaaaaaaaa
+07 (W): aaaaaaaaaaaaaaaaaaaaaaaa
+08 (C): line 20aaaaaaaaaaaaaaaaaa
+09 (W): aaaaaaaaaaaaaaaaaaaaaaaa
+

zellij-server/src/panes/unit/snapshots/zellij_server__panes__grid__grid_tests__scroll_up.snap

@@ -0,0 +1,16 @@
+---
+source: zellij-server/src/panes/./unit/grid_tests.rs
+expression: "format!(\"{:?}\", grid)"
+
+---
+00 (C): line 10aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+01 (C): line 11aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+02 (C): line 12aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+03 (C): line 13aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+04 (C): line 14aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+05 (C): line 15aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+06 (C): line 16aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+07 (C): line 17aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+08 (C): line 18aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+09 (C): line 19aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+

zellij-server/src/panes/unit/snapshots/zellij_server__panes__grid__grid_tests__scroll_up_decrease_width_and_scroll_down.snap

@@ -0,0 +1,16 @@
+---
+source: zellij-server/src/panes/./unit/grid_tests.rs
+expression: "format!(\"{:?}\", grid)"
+
+---
+00 (C): line 11aaaaaaaaaaaaaaaaaa
+01 (W): aaaaaaaaaaaaaaaaaaaaaaaa
+02 (C): line 12aaaaaaaaaaaaaaaaaa
+03 (W): aaaaaaaaaaaaaaaaaaaaaaaa
+04 (C): line 13aaaaaaaaaaaaaaaaaa
+05 (W): aaaaaaaaaaaaaaaaaaaaaaaa
+06 (C): line 14aaaaaaaaaaaaaaaaaa
+07 (W): aaaaaaaaaaaaaaaaaaaaaaaa
+08 (C): line 15aaaaaaaaaaaaaaaaaa
+09 (W): aaaaaaaaaaaaaaaaaaaaaaaa
+

zellij-server/src/panes/unit/snapshots/zellij_server__panes__grid__grid_tests__scroll_up_increase_width_and_scroll_down.snap

@@ -0,0 +1,16 @@
+---
+source: zellij-server/src/panes/./unit/grid_tests.rs
+expression: "format!(\"{:?}\", grid)"
+
+---
+00 (C): line 11aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+01 (C): line 12aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+02 (C): line 13aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+03 (C): line 14aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+04 (C): line 15aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+05 (C): line 16aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+06 (C): line 17aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+07 (C): line 18aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+08 (C): line 19aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+09 (C): line 20aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+

zellij-server/src/panes/unit/snapshots/zellij_server__panes__grid__grid_tests__scroll_up_with_line_wraps.snap

@@ -0,0 +1,16 @@
+---
+source: zellij-server/src/panes/./unit/grid_tests.rs
+expression: "format!(\"{:?}\", grid)"
+
+---
+00 (W): aaaaaaaaaaaaaaaaaaaaaaaa
+01 (C): line 16aaaaaaaaaaaaaaaaaa
+02 (W): aaaaaaaaaaaaaaaaaaaaaaaa
+03 (C): line 17aaaaaaaaaaaaaaaaaa
+04 (W): aaaaaaaaaaaaaaaaaaaaaaaa
+05 (C): line 18aaaaaaaaaaaaaaaaaa
+06 (W): aaaaaaaaaaaaaaaaaaaaaaaa
+07 (C): line 19aaaaaaaaaaaaaaaaaa
+08 (W): aaaaaaaaaaaaaaaaaaaaaaaa
+09 (C): line 20aaaaaaaaaaaaaaaaaa
+