[SOLR-10472] Fix uninversioning of (single valued) PointFields & clean up some related code

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 6.6, 7.0
• Assignee: Chris M. Hostetter
• Reporter: Chris M. Hostetter
• Created: 08/Apr/17 03:55
• Updated: 08/Jun/19 18:20
• Resolved: 19/Apr/17 01:05

Description

In getting caught up with the new PointsField work in SOLR-8396 & SOLR-9987 I realized:

• There's some inconsistencies/contridictions in how the new field types implement FieldType.getUninversionType vs some of the error handling added to methods like SchemaField.checkSortability.
• as part of SOLR-9987, SORTED_foo constants were added to UninvertingReader and used in the getUninversionType methods for PointFields – even though those constants are useless (because UninvertingReader doesn't support uninverting multivalued points: SOLR-9202)
• the changes made to methods like SchemaField.checkSortability to explicitly check isPointsField should have never been needed if those methods were paying attention to getUninversionType – but those types of checks weren't added when getUninversionType was introduced (the existing checks pre-date the DocValues API, back where any single-valued indexed field was implicitily "uninvertable")
• If all of the above is corrected, the only thing preventing UninvertedReader from working properly with Solr's new PointField types (in the single valued case) is a trivial bug in IndexSchema (being presumptutious about what is uninvertable)

I'm opening this issue to track fixing all of this, such that the end result will be:

• single valued PointFields will be uninvertable (ie: sortable even if they don't have docvalues)
• error handling code will be simplified
• unused/unsupported/misleading constants in UninvertingReader will be removed.

Issue Links

• is related to: SOLR-10872 _version_ returns exception when changed to point field