FIX: Undo/redo delete/add page

Now we can undo adding or deleting worksheets

base/src/test/user_model/mod.rs

@@ -16,6 +16,7 @@ mod test_paste_csv;
 mod test_rename_sheet;
 mod test_row_column;
 mod test_sheet_state;
+mod test_sheets_undo_redo;
 mod test_styles;
 mod test_to_from_bytes;
 mod test_undo_redo;

base/src/test/user_model/test_add_delete_sheets.rs

@@ -25,9 +25,6 @@ fn add_undo_redo() {
     assert_eq!(model.get_formatted_cell_value(2, 1, 1), Ok("6".to_string()));
 
     model.delete_sheet(1).unwrap();
-
-    assert!(!model.can_undo());
-    assert!(!model.can_redo());
 }
 
 #[test]

base/src/test/user_model/test_sheets_undo_redo.rs

@@ -0,0 +1,52 @@
+#![allow(clippy::unwrap_used)]
+
+use crate::test::util::new_empty_model;
+use crate::UserModel;
+
+#[test]
+fn basic_undo_redo() {
+    let model = new_empty_model();
+    let mut model = UserModel::from_model(model);
+    assert_eq!(model.get_selected_sheet(), 0);
+
+    model.new_sheet().unwrap();
+    assert_eq!(model.get_selected_sheet(), 1);
+    model.undo().unwrap();
+    assert_eq!(model.get_selected_sheet(), 0);
+    {
+        let props = model.get_worksheets_properties();
+        assert_eq!(props.len(), 1);
+        let view = model.get_selected_view();
+        assert_eq!(view.sheet, 0);
+    }
+
+    model.redo().unwrap();
+    assert_eq!(model.get_selected_sheet(), 1);
+    {
+        let props = model.get_worksheets_properties();
+        assert_eq!(props.len(), 2);
+        let view = model.get_selected_view();
+
+        assert_eq!(view.sheet, 1);
+    }
+}
+
+#[test]
+fn delete_undo() {
+    let model = new_empty_model();
+    let mut model = UserModel::from_model(model);
+    assert_eq!(model.get_selected_sheet(), 0);
+
+    model.new_sheet().unwrap();
+    assert_eq!(model.get_selected_sheet(), 1);
+    model.set_user_input(1, 1, 1, "42").unwrap();
+    model.set_user_input(1, 1, 2, "=A1*2").unwrap();
+    model.delete_sheet(1).unwrap();
+
+    assert_eq!(model.get_selected_sheet(), 0);
+
+    model.undo().unwrap();
+    assert_eq!(model.get_selected_sheet(), 1);
+    model.redo().unwrap();
+    assert_eq!(model.get_selected_sheet(), 0);
+}

base/src/user_model/common.rs

@@ -412,9 +412,13 @@ impl UserModel {
     /// See also:
     /// * [Model::delete_sheet]
     pub fn delete_sheet(&mut self, sheet: u32) -> Result<(), String> {
-        self.push_diff_list(vec![Diff::DeleteSheet { sheet }]);
-        // There is no coming back
-        self.history.clear();
+        let worksheet = self.model.workbook.worksheet(sheet)?;
+
+        self.push_diff_list(vec![Diff::DeleteSheet {
+            sheet,
+            old_data: Box::new(worksheet.clone()),
+        }]);
+
         let sheet_count = self.model.workbook.worksheets.len() as u32;
         // If we are deleting the last sheet we need to change the selected sheet
         if sheet == sheet_count - 1 && sheet_count > 1 {
@@ -1972,11 +1976,11 @@ impl UserModel {
                     new_value: _,
                     old_value,
                 } => self.model.set_frozen_columns(*sheet, *old_value)?,
-                Diff::DeleteSheet { sheet: _ } => {
-                    // do nothing
-                }
                 Diff::NewSheet { index, name: _ } => {
                     self.model.delete_sheet(*index)?;
+                    if *index > 0 {
+                        self.set_selected_sheet(*index - 1)?;
+                    }
                 }
                 Diff::RenameSheet {
                     index,
@@ -2043,6 +2047,32 @@ impl UserModel {
                     self.model
                         .set_cell_style(*sheet, *row, *column, old_style)?;
                 }
+                Diff::DeleteSheet { sheet, old_data } => {
+                    needs_evaluation = true;
+                    let sheet_name = &old_data.name.clone();
+                    let sheet_index = *sheet;
+                    let sheet_id = old_data.sheet_id;
+                    self.model
+                        .insert_sheet(sheet_name, sheet_index, Some(sheet_id))?;
+                    let worksheet = self.model.workbook.worksheet_mut(*sheet)?;
+                    for (row, row_data) in &old_data.sheet_data {
+                        for (column, cell) in row_data {
+                            worksheet.update_cell(*row, *column, cell.clone())?;
+                        }
+                    }
+                    worksheet.rows = old_data.rows.clone();
+                    worksheet.cols = old_data.cols.clone();
+                    worksheet.show_grid_lines = old_data.show_grid_lines;
+                    worksheet.frozen_columns = old_data.frozen_columns;
+                    worksheet.frozen_rows = old_data.frozen_rows;
+                    worksheet.state = old_data.state.clone();
+                    worksheet.color = old_data.color.clone();
+                    worksheet.merge_cells = old_data.merge_cells.clone();
+                    worksheet.shared_formulas = old_data.shared_formulas.clone();
+                    self.model.reset_parsed_structures();
+
+                    self.set_selected_sheet(sheet_index)?;
+                }
             }
         }
         if needs_evaluation {
@@ -2145,9 +2175,15 @@ impl UserModel {
                     new_value,
                     old_value: _,
                 } => self.model.set_frozen_columns(*sheet, *new_value)?,
-                Diff::DeleteSheet { sheet } => self.model.delete_sheet(*sheet)?,
+                Diff::DeleteSheet { sheet, old_data: _ } => {
+                    self.model.delete_sheet(*sheet)?;
+                    if *sheet > 0 {
+                        self.set_selected_sheet(*sheet - 1)?;
+                    }
+                }
                 Diff::NewSheet { index, name } => {
                     self.model.insert_sheet(name, *index, None)?;
+                    self.set_selected_sheet(*index)?;
                 }
                 Diff::RenameSheet {
                     index,

base/src/user_model/history.rs

@@ -2,7 +2,7 @@ use std::collections::HashMap;
 
 use bitcode::{Decode, Encode};
 
-use crate::types::{Cell, Col, Row, SheetState, Style};
+use crate::types::{Cell, Col, Row, SheetState, Style, Worksheet};
 
 #[derive(Clone, Encode, Decode)]
 pub(crate) struct RowData {
@@ -83,6 +83,10 @@ pub(crate) enum Diff {
         column: i32,
         old_data: Box<ColumnData>,
     },
+    DeleteSheet {
+        sheet: u32,
+        old_data: Box<Worksheet>,
+    },
     SetFrozenRowsCount {
         sheet: u32,
         new_value: i32,
@@ -93,9 +97,6 @@ pub(crate) enum Diff {
         new_value: i32,
         old_value: i32,
     },
-    DeleteSheet {
-        sheet: u32,
-    },
     NewSheet {
         index: u32,
         name: String,
@@ -174,11 +175,6 @@ impl History {
             None => None,
         }
     }
-
-    pub fn clear(&mut self) {
-        self.redo_stack = vec![];
-        self.undo_stack = vec![];
-    }
 }
 
 #[derive(Clone, Encode, Decode)]