reports: Add BaseODS.row_count() method.

conservancy_beancount/reports/core.py

@@ -1342,6 +1342,12 @@ class BaseODS(BaseSpreadsheet[RT, ST], metaclass=abc.ABCMeta):
         self.sheet.addElement(row)
         return row
 
+    def row_count(self, sheet: Optional[odf.table.Table]=None) -> int:
+        if sheet is None:
+            sheet = self.sheet
+        TableRow = odf.table.TableRow
+        return sum(1 for cell in sheet.childNodes if cell.isInstanceOf(TableRow))
+
     def balance_cell(self, balance: Balance, **attrs: Any) -> odf.table.TableCell:
         balance = balance.clean_copy() or balance
         balance_currency_count = len(balance)

tests/test_reports_spreadsheet.py

@@ -526,6 +526,15 @@ def test_ods_writer_add_row_empty(ods_writer):
     assert row.firstChild is None
     assert row.getAttribute('stylename') == 'blank'
 
+@pytest.mark.parametrize('col_count', range(3))
+def test_ods_writer_row_count(ods_writer, col_count):
+    for _ in range(col_count):
+        ods_writer.sheet.addElement(odf.table.TableColumn())
+    assert ods_writer.row_count() == 0
+    for expected in range(1, 4):
+        ods_writer.sheet.addElement(odf.table.TableRow())
+        assert ods_writer.row_count() == expected
+
 def test_ods_writer_balance_cell_empty(ods_writer):
     balance = core.Balance()
     cell = ods_writer.balance_cell(balance)