Snapshot test for sorting

tests/snapshot_tests/snapshot_apps/data_table_sort.py

@@ -0,0 +1,44 @@
+from textual.app import App, ComposeResult
+from textual.binding import Binding
+from textual.widgets import DataTable
+
+# Shuffled around a bit to exercise sorting.
+ROWS = [
+    ("lane", "swimmer", "country", "time"),
+    (5, "Chad le Clos", "South Africa", 51.14),
+    (4, "Joseph Schooling", "Singapore", 50.39),
+    (2, "Michael Phelps", "United States", 51.14),
+    (6, "László Cseh", "Hungary", 51.14),
+    (3, "Li Zhuhao", "China", 51.26),
+    (8, "Mehdy Metella", "France", 51.58),
+    (7, "Tom Shields", "United States", 51.73),
+    (10, "Darren Burns", "Scotland", 51.84),
+    (1, "Aleksandr Sadovnikov", "Russia", 51.84),
+]
+
+
+class TableApp(App):
+    BINDINGS = [
+        Binding("s", "sort", "Sort"),
+    ]
+
+    def compose(self) -> ComposeResult:
+        yield DataTable()
+
+    def on_mount(self) -> None:
+        table = self.query_one(DataTable)
+        table.focus()
+        rows = iter(ROWS)
+        column_labels = next(rows)
+        for column in column_labels:
+            table.add_column(column, key=column)
+        table.add_rows(rows)
+
+    def action_sort(self):
+        table = self.query_one(DataTable)
+        table.sort("time", "lane")
+
+
+app = TableApp()
+if __name__ == "__main__":
+    app.run()

tests/snapshot_tests/test_snapshots.py

@@ -103,6 +103,11 @@ def test_datatable_column_cursor_render(snap_compare):
     assert snap_compare(SNAPSHOT_APPS_DIR / "data_table_column_cursor.py", press=press)
 
 
+def test_datatable_sort_multikey(snap_compare):
+    press = ["down", "right", "s"]  # Also checks that sort doesn't move cursor.
+    assert snap_compare(SNAPSHOT_APPS_DIR / "data_table_sort.py", press=press)
+
+
 def test_footer_render(snap_compare):
     assert snap_compare(WIDGET_EXAMPLES_DIR / "footer.py")