[ARROW-9941] [Python] Better string representation for extension types

• Type: Wish
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 2.0.0
• Component/s: C++, Python
• Labels: pull-request-available
• External issue URL: https://github.com/apache/arrow/issues/17338
• Assignee: Diana Clarke
• Reporter: Antoine Pitrou
• Created: 08/Sep/20 13:16
• Updated: 11/Jan/23 08:10
• Resolved: 05/Oct/20 16:10

Description

When one defines an extension type in Python (by subclassing PyExtensionType) and uses that type e.g. in a Arrow table, the printed schema looks like this:

pyarrow.Table
a: extension<arrow.py_extension_type>
b: extension<arrow.py_extension_type>

... which isn't very informative. PyExtensionType could perhaps override ToString() and call str on the type instance.

Issue Links

• links to: GitHub Pull Request #8312