test: cover external table locations binding

AI Disclosure: This code was written in part by an AI agent.:

Author: timsaucer

python/datafusion/expr.py

@@ -101,12 +101,14 @@
 def _create_external_table_location(self: Any) -> str:
     """Return the first external table location.
 
+    Use :meth:`CreateExternalTable.locations` instead.
+
     Examples:
         >>> class Command:
         ...     def locations(self) -> list[str]:
         ...         return ["data.csv"]
-        >>> _create_external_table_location(Command())
-        'data.csv'
+        >>> Command().locations()
+        ['data.csv']
     """
     locations = self.locations()
     return locations[0] if locations else ""

python/tests/test_catalog.py

@@ -123,6 +123,11 @@ def register_catalog(
 class CustomTableProviderFactory(dfn.catalog.TableProviderFactory):
     def create(self, cmd: dfn.expr.CreateExternalTable):
         assert cmd.name() == "test_table_factory"
+        assert cmd.locations() == ["foo"]
+
+        with pytest.warns(DeprecationWarning, match=r"location\(\).+deprecated"):
+            assert cmd.location() == "foo"
+
         return create_dataset()
 
 

python/tests/test_expr.py

@@ -19,7 +19,6 @@
 from concurrent.futures import ThreadPoolExecutor
 from datetime import date, datetime, time, timezone
 from decimal import Decimal
-from unittest.mock import MagicMock
 
 import arro3.core
 import nanoarrow
@@ -40,7 +39,6 @@
     BinaryExpr,
     Column,
     CopyTo,
-    CreateExternalTable,
     CreateIndex,
     DescribeTable,
     DmlStatement,
@@ -70,17 +68,6 @@ def test_ctx():
     return ctx
 
 
-def test_create_external_table_location_is_deprecated():
-    """The singular location accessor delegates to locations()."""
-    command = MagicMock()
-    command.locations.return_value = ["first.csv", "second.csv"]
-
-    with pytest.warns(DeprecationWarning, match=r"location\(\).+deprecated"):
-        location = CreateExternalTable.location(command)
-
-    assert location == "first.csv"
-
-
 def test_projection(test_ctx):
     df = test_ctx.sql("select c1, 123, c1 < 123 from test")
     plan = df.logical_plan()