Merge PR #3226

crates/engine/src/cmd/edit.rs

@@ -36,7 +36,7 @@ use go_to::go_to_special;
 use go_to::{GO_TO_MAX_AREAS, GO_TO_RECENT, reference_parts};
 use paste_special::paste_special;
 pub(crate) use paste_special::{rewrite_all_formulas, rewrite_cell_links, rewrite_python_refs};
-use selection::{select_all, select_col, select_region, select_row, selection_move, selection_next, selection_set};
+use selection::{select_all, select_col, select_region, select_row, selection_move, selection_next, selection_next_corner, selection_set};
 
 pub fn specs() -> Vec<CommandSpec> {
     vec![
@@ -62,6 +62,15 @@ pub fn specs() -> Vec<CommandSpec> {
         cmd!(noundo "selection.set", "Select", [], None, "{range: \"A1:B2,D4\" | cell, active?: \"A1\", sheet?}", has_doc, selection_set),
         cmd!(noundo "selection.move", "Move Selection", [], None, "{dr, dc, extend?: bool, jump?: bool (Ctrl+arrow), page?: bool}", has_doc, selection_move),
         cmd!(noundo "selection.next", "Next Cell in Selection", [], None, "{forward?: true, byRow?: false} (Enter/Tab inside a selection)", has_doc, selection_next),
+        cmd!(
+            noundo "selection.nextCorner",
+            "Next Corner of Selection",
+            [],
+            Some("Ctrl+."),
+            "{} (the active cell moves clockwise to the next corner of the selected area, which stays selected)",
+            has_doc,
+            selection_next_corner
+        ),
         cmd!(noundo "edit.selectAll", "Select All", ["Edit"], Some("Cmd+A"), "{} (current region first, then the whole sheet)", has_doc, select_all),
         cmd!(noundo "selection.currentRegion", "Select Current Region", [], Some("Ctrl+Shift+8"), "{}", has_doc, select_region),
         cmd!(noundo "selection.row", "Select Entire Row", [], Some("Shift+Space"), "{}", has_doc, select_row),

crates/engine/src/cmd/edit/selection.rs

@@ -137,6 +137,23 @@ pub(super) fn selection_next(s: &mut Session, p: &Json) -> Result<Json> {
     Ok(json!({"active": d.selection.active.a1()}))
 }
 
+pub(super) fn selection_next_corner(s: &mut Session, _: &Json) -> Result<Json> {
+    let d = s.doc_mut()?;
+    let Some(sheet) = d.wb.active() else { return Err(EngineError::NoDocument) };
+    // A corner in a merged cell lands on its top-left cell. One in a hidden row or column, one
+    // the sheet's protection doesn't let you select, and a merged cell that starts outside the
+    // selected area are skipped.
+    let area = d.selection.current();
+    let stop = |c: CellRef| {
+        Some(sheet.merge_at(c).map_or(c, |m| m.start))
+            .filter(|c| area.contains(*c) && !sheet.is_row_hidden(c.row) && !sheet.is_col_hidden(c.col) && cell_selectable(&d.wb, sheet, *c))
+    };
+    let mut next = d.selection.clone();
+    next.next_corner_by(stop);
+    d.selection = next;
+    Ok(json!({"active": d.selection.active.a1(), "selection": d.selection.a1()}))
+}
+
 pub(super) fn select_all(s: &mut Session, _: &Json) -> Result<Json> {
     let d = s.doc_mut()?;
     let Some(sheet) = d.wb.active() else { return Err(EngineError::NoDocument) };

crates/engine/src/cmd/edit/tests.rs

@@ -439,3 +439,75 @@ fn replace_case_insensitive_keeps_text_when_folding_moves_boundaries() {
     let sh = s.doc().unwrap().wb.active().unwrap();
     assert_eq!(sh.value(CellRef::new(0, 0)), Value::text(text));
 }
+
+#[test]
+fn next_corner_of_selection_goes_clockwise_and_anchors_there() {
+    // #1442, as Excel does it: B2 → D2 → D4 → B4 → B2, the area stays selected, and Shift+arrows
+    // then move the corner opposite the new active cell.
+    let mut s = Session::new();
+    s.new_workbook();
+    s.execute("selection.set", json!({"range": "B2:D4", "active": "B2"})).unwrap();
+    let mut seen = Vec::new();
+    for _ in 0..4 {
+        let r = s.execute("selection.nextCorner", json!({})).unwrap();
+        assert_eq!(r["selection"], "B2:D4");
+        seen.push(r["active"].as_str().unwrap().to_string());
+    }
+    assert_eq!(seen, ["D2", "D4", "B4", "B2"]);
+    s.execute("selection.nextCorner", json!({})).unwrap();
+    s.execute("selection.nextCorner", json!({})).unwrap();
+    s.execute("selection.move", json!({"dr": 0, "dc": 1, "extend": true})).unwrap();
+    assert_eq!(s.doc().unwrap().selection.current().a1(), "C2:D4");
+    // One row goes end to end; a single cell stays.
+    s.execute("selection.set", json!({"range": "B2:D2", "active": "B2"})).unwrap();
+    assert_eq!(s.execute("selection.nextCorner", json!({})).unwrap()["active"], "D2");
+    assert_eq!(s.execute("selection.nextCorner", json!({})).unwrap()["active"], "B2");
+    s.execute("selection.set", json!({"range": "C5"})).unwrap();
+    assert_eq!(s.execute("selection.nextCorner", json!({})).unwrap()["active"], "C5");
+}
+
+#[test]
+fn next_corner_skips_corners_the_sheet_protection_does_not_let_you_select() {
+    // With locked cells unselectable, Ctrl+. goes on to the next corner it may select.
+    let mut s = Session::new();
+    s.new_workbook();
+    s.execute("home.lockCell", json!({"range": "B2:C3", "on": false})).unwrap();
+    s.execute("selection.set", json!({"range": "B2:D3", "active": "B2"})).unwrap();
+    s.execute("review.protectSheet", json!({"selectLockedCells": false})).unwrap();
+    let r = s.execute("selection.nextCorner", json!({})).unwrap();
+    assert_eq!((r["active"].as_str(), r["selection"].as_str()), (Some("B3"), Some("B2:D3")), "D2 and D3 are locked");
+    assert_eq!(s.execute("selection.nextCorner", json!({})).unwrap()["active"], "B2");
+}
+
+#[test]
+fn next_corner_stops_once_on_a_merged_corner_at_its_top_left_cell() {
+    // A corner inside a merged cell is that merged cell, whose active cell is its top-left one.
+    let mut s = Session::new();
+    s.new_workbook();
+    s.execute("home.mergeCells", json!({"range": "C2:D2"})).unwrap();
+    s.execute("selection.set", json!({"range": "B2:D3", "active": "B2"})).unwrap();
+    let seen: Vec<String> = (0..4).map(|_| s.execute("selection.nextCorner", json!({})).unwrap()["active"].as_str().unwrap().to_string()).collect();
+    assert_eq!(seen, ["C2", "D3", "B3", "B2"]);
+    // A selection that is one merged cell has no other corner.
+    s.execute("selection.set", json!({"range": "C2:D2", "active": "C2"})).unwrap();
+    assert_eq!(s.execute("selection.nextCorner", json!({})).unwrap()["active"], "C2");
+}
+
+#[test]
+fn next_corner_skips_hidden_corners_and_stays_inside_the_selected_area() {
+    // A corner in a hidden column is passed over, as keyboard moves pass over hidden cells.
+    let mut s = Session::new();
+    s.new_workbook();
+    s.execute("home.hideColumns", json!({"cols": "D:D"})).unwrap();
+    s.execute("selection.set", json!({"range": "B2:D3", "active": "B2"})).unwrap();
+    assert_eq!(s.execute("selection.nextCorner", json!({})).unwrap()["active"], "B3");
+    // Column C selected with B1:C1 merged: its top corner's merged cell starts in column B,
+    // outside the selection, so the active cell doesn't go there.
+    let mut s = Session::new();
+    s.new_workbook();
+    s.execute("home.mergeCells", json!({"range": "B1:C1"})).unwrap();
+    s.execute("selection.set", json!({"cell": "C5"})).unwrap();
+    s.execute("selection.column", json!({})).unwrap();
+    let r = s.execute("selection.nextCorner", json!({})).unwrap();
+    assert_eq!((r["active"].as_str(), r["selection"].as_str()), (Some("C1048576"), Some("C:C")));
+}