TST: check compatibility with pyarrow types_mapper parameter (#44369)

Author: tswast

pandas/tests/arrays/masked/test_arrow_compat.py

@@ -36,6 +36,27 @@ def test_arrow_roundtrip(data):
     tm.assert_frame_equal(result, df)
 
 
+def test_dataframe_from_arrow_types_mapper():
+    def types_mapper(arrow_type):
+        if pa.types.is_boolean(arrow_type):
+            return pd.BooleanDtype()
+        elif pa.types.is_integer(arrow_type):
+            return pd.Int64Dtype()
+
+    bools_array = pa.array([True, None, False], type=pa.bool_())
+    ints_array = pa.array([1, None, 2], type=pa.int64())
+    small_ints_array = pa.array([-1, 0, 7], type=pa.int8())
+    record_batch = pa.RecordBatch.from_arrays(
+        [bools_array, ints_array, small_ints_array], ["bools", "ints", "small_ints"]
+    )
+    result = record_batch.to_pandas(types_mapper=types_mapper)
+    bools = pd.Series([True, None, False], dtype="boolean")
+    ints = pd.Series([1, None, 2], dtype="Int64")
+    small_ints = pd.Series([-1, 0, 7], dtype="Int64")
+    expected = pd.DataFrame({"bools": bools, "ints": ints, "small_ints": small_ints})
+    tm.assert_frame_equal(result, expected)
+
+
 def test_arrow_load_from_zero_chunks(data):
     # GH-41040