DataTable - fix crash when selection made in empty table (#1973)

CHANGELOG.md

@@ -32,6 +32,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 - Fixed bug that prevented pilot from pressing some keys https://github.com/Textualize/textual/issues/1815
 - DataTable race condition that caused crash https://github.com/Textualize/textual/pull/1962
+- DataTable crash when enter pressed when table is empty https://github.com/Textualize/textual/pull/1973
 
 ## [0.13.0] - 2023-03-02
 

src/textual/widgets/_data_table.py

@@ -1975,6 +1975,8 @@ class DataTable(ScrollView, Generic[CellType], can_focus=True):
         """Post the appropriate message for a selection based on the `cursor_type`."""
         cursor_coordinate = self.cursor_coordinate
         cursor_type = self.cursor_type
+        if len(self._data) == 0:
+            return
         cell_key = self.coordinate_to_cell_key(cursor_coordinate)
         if cursor_type == "cell":
             self.post_message(

tests/test_data_table.py

@@ -1,14 +1,12 @@
 from __future__ import annotations
 
 import pytest
-from rich.style import Style
 from rich.text import Text
 
 from textual._wait import wait_for_idle
 from textual.actions import SkipAction
 from textual.app import App
 from textual.coordinate import Coordinate
-from textual.events import Click, MouseMove
 from textual.geometry import Offset
 from textual.message import Message
 from textual.widgets import DataTable
@@ -166,6 +164,13 @@ async def test_datatable_message_emission():
         assert app.message_names == expected_messages
 
 
+async def test_empty_table_interactions():
+    app = DataTableApp()
+    async with app.run_test() as pilot:
+        await pilot.press("enter", "up", "down", "left", "right")
+        assert app.message_names == []
+
+
 async def test_add_rows():
     app = DataTableApp()
     async with app.run_test():