[LUCENE-9248] Change internal code names of postingsFormats to use 84 suffix

• Type: Improvement
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Component/s: core/codecs
• Lucene Fields: New
• Assignee: David Smiley
• Reporter: David Smiley
• Created: 24/Feb/20 18:53
• Updated: 28/Aug/22 15:59

Description

Some postings formats write the postings differently as of Lucene 8.4 due to changes – LUCENE-9027 and LUCENE-9116. Blocktree was transitioned in a backwards-compatible way but some (all?) others were not. Consequently an attempt of the new version to read an old index will fail due to some non-obvious error. I propose here using a simple version suffix on these postings formats like "84" (thus "FST84" as one example). I see some already use a suffix but were not bumped for 8.4. This is a really simple change and doesn't address the problem of us not noticing future needs to version bump.

Issue Links

• relates to: LUCENE-9222 Detect upgrades with non-default formats