[Python] Segmentation fault when comparing schema with None

[asfimport]

When comparing a schema with a Python None I get a segmentation fault.

This is a regression to 0.13.0

In [2]: import pyarrow as pa

In [3]: pa.schema([pa.field("something", pa.int64())]).equals(None)
[1]    82085 segmentation fault  ipython

System information:
System Version: macOS 10.13.6 (17G6030)
Kernel Version: Darwin 17.7.0
Python 3.6.7

Reporter: Florian Jetter / @fjetter
Assignee: Joris Van den Bossche / @jorisvandenbossche

PRs and other links:

• GitHub Pull Request #4839

_{Note: This issue was originally created as ARROW-5873. Please see the migration documentation for further details.}

[asfimport]

Joris Van den Bossche / @jorisvandenbossche:
Thanks for the report. I can confirm the segfault (although I also see it with 0.13.0)

[asfimport]

Florian Jetter / @fjetter:
Turns out we've seen this prior to 0.14.0 as well but not entirely reproducible, c.f. JDASoftwareGroup/kartothek#54

but on my machine it works fine on 0.13.0

[asfimport]

Krisztian Szucs / @kszucs:
Issue resolved by pull request 4839
#4839