intersphinx: Don't warn about pure-duplicate ambiguous definitions when loading 'objects.inv' entries.

[jayaddison]

Feature or Bugfix

• Bugfix

Purpose

• Don't emit a warning at inventory load time if two ambiguously-resolved Intersphinx objects.inv entries resolve to exactly the same result (i.e. are duplicates that differ only by lowercase/uppercase characters).

Detail

• Use set-comparison of the reference fields.
• Do log a debug message for reference.

Todo / open questions

• Also handle a similar scenario in some Intersphinx entity resolution code introduced at the same time?
  • TBD. Moved to separate PR intersphinx: Reduce log message severity when ambiguous target resolves to a duplicate #12587.

Relates

• Warning introduced in Intersphinx: log warnings for ambiguous target resolutions. #12329.
• Resolves Warning about duplicate definitions in intersphinx mapping #12585.

Edit: clarify the false-positive warning that is filtered by this branch.

[AA-Turner]

Oh, this should have had a CHANGES entry...

A

[jayaddison]

Oh, this should have had a CHANGES entry...

"Reduce log severity of detected ambiguous Intersphinx inventory items that are found to be case-insensitive duplicates." ?

[jayaddison]

(rationale: they are still resolved ambiguously, but since they're duplicates, they're basically innocuous)

[AA-Turner]

Added a variant of that as 12064e0.

A

[jayaddison]

Thank you!