Fix ruff errors

Author: kosiew

python/datafusion/dataframe.py

@@ -49,6 +49,7 @@
     import pyarrow as pa
 
     from datafusion._internal import DataFrame as DataFrameInternal
+    from datafusion._internal import DisplayConfig
     from datafusion._internal import expr as expr_internal
 
 from enum import Enum
@@ -823,14 +824,17 @@ def configure_display(
         """Configure display options for DataFrame representation.
 
         Args:
-            max_table_bytes: Maximum bytes to display for table presentation (default: 2MB).
+            max_table_bytes: Maximum bytes to display for table presentation
+                             (default: 2MB).
                              Set to lower value for large tables to limit memory usage.
             min_table_rows: Minimum number of table rows to display (default: 20).
                             This is used for initial display and in notebooks.
-            max_cell_length: Maximum length of a cell before it gets minimized (default: 25).
+            max_cell_length: Maximum length of a cell before it gets minimized
+                             (default: 25).
                              Longer cells will be truncated with an expand button.
-            max_table_rows_in_repr: Maximum number of rows to display in string representation
-                                   (default: 10).
+            max_table_rows_in_repr: Maximum number of rows to display in string
+                                    representation
+                                    (default: 10).
 
         Raises:
             ValueError: If any of the provided values are less than or equal to 0.
@@ -844,7 +848,8 @@ def configure_display(
                 max_table_rows_in_repr,
             )
         ):
-            raise ValueError("All values must be greater than 0.")
+            error_msg = "All values must be greater than 0."
+            raise ValueError(error_msg)
 
         self.df.configure_display(
             max_table_bytes, min_table_rows, max_cell_length, max_table_rows_in_repr
@@ -855,8 +860,12 @@ def reset_display_config(self) -> None:
         self.df.reset_display_config()
 
     @property
-    def display_config(self):
-        """Get the current display configuration."""
+    def display_config(self) -> DisplayConfig:
+        """Get the current display configuration.
+
+        Returns:
+            DisplayConfig: The current display configuration settings
+        """
         return self.df.display_config
 
     @deprecated("Use :py:func:`unnest_columns` instead.")

python/tests/test_dataframe.py

@@ -1306,7 +1306,8 @@ def test_configure_display(df):
 
     # Test with negative values
     # This tests for expected behavior when users accidentally pass negative values
-    # Since these are usize in Rust, we expect a Python ValueError when trying to pass negative values
+    # Since these are usize in Rust, we expect a Python ValueError when trying to pass
+    # negative values.
     with pytest.raises(ValueError, match=r".*must be greater than 0.*"):
         df.configure_display(max_table_bytes=-1)
 
@@ -1393,9 +1394,10 @@ def test_max_table_bytes_display(ctx):
     limited_row_count = limited_html.count("<tr>") - 1
 
     # Verify fewer rows are displayed with the byte limit
-    assert (
-        limited_row_count < default_row_count
-    ), f"Expected fewer rows with byte limit. Default: {default_row_count}, Limited: {limited_row_count}"
+    assert limited_row_count < default_row_count, (
+        f"Expected fewer rows with byte limit. "
+        f"Default: {default_row_count}, Limited: {limited_row_count}"
+    )
 
     # "Data truncated" should be present when limited
     assert "Data truncated" in limited_html
@@ -1504,7 +1506,9 @@ def _create_numeric_test_df(ctx, rows) -> DataFrame:
 
 
 def test_max_table_rows_in_repr(ctx):
-    """Test that max_table_rows_in_repr controls the number of rows in string representation."""
+    """Test that max_table_rows_in_repr controls the number of rows in string
+    representation.
+    """
     # Create a dataframe with more rows than the default max_table_rows_in_repr (10)
     rows = 20
     df = _create_numeric_test_df(ctx, rows)