UPDATE: Adds 'user model' API (#27)

* bump version for documentation
* Fixes wrong doc comment
* renames old APIs to be consistent

base/src/test/user_model/test_add_delete_sheets.rs

@@ -0,0 +1,58 @@
+#![allow(clippy::unwrap_used)]
+
+use crate::{constants::DEFAULT_COLUMN_WIDTH, UserModel};
+
+#[test]
+fn add_undo_redo() {
+    let mut model = UserModel::new_empty("model", "en", "UTC").unwrap();
+    model.new_sheet();
+    model.set_user_input(1, 1, 1, "=1 + 1").unwrap();
+    model.set_user_input(1, 1, 2, "=A1*3").unwrap();
+    model
+        .set_column_width(1, 5, 5.0 * DEFAULT_COLUMN_WIDTH)
+        .unwrap();
+    model.new_sheet();
+    model.set_user_input(2, 1, 1, "=Sheet2!B1").unwrap();
+
+    model.undo().unwrap();
+    model.undo().unwrap();
+
+    assert!(model.get_formatted_cell_value(2, 1, 1).is_err());
+
+    model.redo().unwrap();
+    model.redo().unwrap();
+
+    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]
+fn new_sheet_propagates() {
+    let mut model = UserModel::new_empty("model", "en", "UTC").unwrap();
+    model.new_sheet();
+
+    let send_queue = model.flush_send_queue();
+
+    let mut model2 = UserModel::new_empty("model", "en", "UTC").unwrap();
+    model2.apply_external_diffs(&send_queue).unwrap();
+    let sheets_info = model2.get_sheets_info();
+    assert_eq!(sheets_info.len(), 2);
+}
+
+#[test]
+fn delete_sheet_propagates() {
+    let mut model = UserModel::new_empty("model", "en", "UTC").unwrap();
+    model.new_sheet();
+    model.delete_sheet(0).unwrap();
+
+    let send_queue = model.flush_send_queue();
+
+    let mut model2 = UserModel::new_empty("model", "en", "UTC").unwrap();
+    model2.apply_external_diffs(&send_queue).unwrap();
+    let sheets_info = model2.get_sheets_info();
+    assert_eq!(sheets_info.len(), 1);
+}