Searchindex fix when objects have the same name

[jakobandersen]

Feature or Bugfix

• Bugfix

Purpose

Store all objects with the same name from different domains in searchindex.js.

Detail

Objects in searchindex.js are stored as a dictionary indexed by the object name. However, it is perfectly reasonable to have, e.g., both a Python and C function with the same name. This PR changes the storage to an array.

To test out:

1. Clone https://github.com/jakobandersen/sphinx_redirect_prototype and build to HTML.
2. Search for "f". This should list at least entries for fpy, fc, and fcpp.
3. Search for g. This only lists the Python function, even though there is a C and C++ function of the same name.

Repeat the same steps with this PR should in step 3 yield all three g objects.

Relates

Started from #9574 (comment)..

[tk0miya]

LGTM. I'm not sure why the names are unique. I guess there is no reason to keep keywords unique. So +1 for this change.

BTW, we need to discuss about the side effect of this change. After this change, the structure of searchindex.js will be changed. It would be a breaking change if some 3rd party tool directly reads. AFAIK, there are no such tools. So I'm okay to merge this into the 4.x branch. But we need to announce it via CHANGES.

[jakobandersen]

@tk0miya, I have added a note to CHANGES to warn about it. While it is indeed a breaking change I think the chance of someone using searchindex.js is somewhat low. The code calls a method on a specific object, passing the index as an object, so if someone is using it they anyway need to mock the interface assumed.
Let me know if you are fine with the PR with this CHANGES entry (or feel free to merge it your self).

[tk0miya]

LGTM. Merging!

[jakobandersen]

Thanks!