[ARROW-8057] [Python] Don't check Schema metadata in __eq__ and __ne__

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.17.0
• Component/s: C++, Python
• Labels: pull-request-available
• External issue URL: https://github.com/apache/arrow/issues/24270
• Assignee: Wes McKinney
• Reporter: Florian Jetter
• Created: 10/Mar/20 10:35
• Updated: 11/Jan/23 07:57
• Resolved: 11/Mar/20 00:13

Description

When performing schema roundtrips, the equality check for fields break. This is a regression from PyArrow 0.16.0

The equality check for entire schemas has never worked (but should from my POV)

import pyarrow.parquet as pq
import pyarrow as pa
print(pa.__version__)
fields = [
    pa.field("bool", pa.bool_()),
    pa.field("byte", pa.binary()),
    pa.field("date", pa.date32()),
    pa.field("datetime64", pa.timestamp("us")),
    pa.field("float32", pa.float64()),
    pa.field("float64", pa.float64()),
    pa.field("int16", pa.int64()),
    pa.field("int32", pa.int64()),
    pa.field("int64", pa.int64()),
    pa.field("int8", pa.int64()),
    pa.field("null", pa.null()),
    pa.field("uint16", pa.uint64()),
    pa.field("uint32", pa.uint64()),
    pa.field("uint64", pa.uint64()),
    pa.field("uint8", pa.uint64()),
    pa.field("unicode", pa.string()),
    pa.field("array_float32", pa.list_(pa.float64())),
    pa.field("array_float64", pa.list_(pa.float64())),
    pa.field("array_int16", pa.list_(pa.int64())),
    pa.field("array_int32", pa.list_(pa.int64())),
    pa.field("array_int64", pa.list_(pa.int64())),
    pa.field("array_int8", pa.list_(pa.int64())),
    pa.field("array_uint16", pa.list_(pa.uint64())),
    pa.field("array_uint32", pa.list_(pa.uint64())),
    pa.field("array_uint64", pa.list_(pa.uint64())),
    pa.field("array_uint8", pa.list_(pa.uint64())),
    pa.field("array_unicode", pa.list_(pa.string())),
]

schema = pa.schema(fields)

buf = pa.BufferOutputStream()
pq.write_metadata(schema, buf)
reader = pa.BufferReader(buf.getvalue().to_pybytes())
reconstructed_schema = pq.read_schema(reader)

assert reconstructed_schema == reconstructed_schema
assert reconstructed_schema[0] == reconstructed_schema[0]
# This breaks on master / regression from 0.16.0 
assert schema[0] == reconstructed_schema[0]

# This never worked but should
assert reconstructed_schema == schema
assert schema == reconstructed_schema

Issue Links

• links to: GitHub Pull Request #6569