GH-53500: Guard Parquet metadata equality against None

python/pyarrow/_parquet.pyx

@@ -108,7 +108,7 @@ cdef class Statistics(_Weakrefable):
         except TypeError:
             return NotImplemented
 
-    def equals(self, Statistics other):
+    def equals(self, Statistics other not None):
         """
         Return whether the two column statistics objects are equal.
 
@@ -521,7 +521,7 @@ cdef class ColumnChunkMetaData(_Weakrefable):
         except TypeError:
             return NotImplemented
 
-    def equals(self, ColumnChunkMetaData other):
+    def equals(self, ColumnChunkMetaData other not None):
         """
         Return whether the two column chunk metadata objects are equal.
 
@@ -919,7 +919,7 @@ cdef class RowGroupMetaData(_Weakrefable):
         except TypeError:
             return NotImplemented
 
-    def equals(self, RowGroupMetaData other):
+    def equals(self, RowGroupMetaData other not None):
         """
         Return whether the two row group metadata objects are equal.
 
@@ -1295,7 +1295,7 @@ cdef class ParquetSchema(_Weakrefable):
         except TypeError:
             return NotImplemented
 
-    def equals(self, ParquetSchema other):
+    def equals(self, ParquetSchema other not None):
         """
         Return whether the two schemas are equal.
 
@@ -1350,7 +1350,7 @@ cdef class ColumnSchema(_Weakrefable):
     def __reduce__(self):
         return ColumnSchema, (self.parent, self.index)
 
-    def equals(self, ColumnSchema other):
+    def equals(self, ColumnSchema other not None):
         """
         Return whether the two column schemas are equal.
 

python/pyarrow/tests/parquet/test_metadata.py

@@ -893,3 +893,28 @@ def test_geospatial_types(parquet_test_datadir):
     column_schema = metadata.schema.column(1)
     assert column_schema.name == "geography"
     assert column_schema.logical_type.type == "GEOGRAPHY"
+
+
+def test_parquet_metadata_equality_with_none():
+    table = pa.table({"a": [1, 2, 3]})
+    with pa.BufferOutputStream() as out:
+        pq.write_table(table, out)
+        buf = out.getvalue()
+    metadata = pq.read_metadata(pa.BufferReader(buf))
+    row_group = metadata.row_group(0)
+    column = row_group.column(0)
+    schema = metadata.schema
+    objects = (
+        metadata,
+        row_group,
+        column,
+        column.statistics,
+        schema,
+        schema.column(0),
+    )
+    none = None
+    for obj in objects:
+        with pytest.raises(TypeError, match="Argument 'other' has incorrect type"):
+            obj.equals(none)
+        assert (obj == none) is False
+        assert (obj != none) is True