Fix component cache for polymorphic field re-renders

[tintinthong]

The point of this PR is to enable polymorphic fields to re-render upon assigning a subclass to a field of baseclass type. Previously, although the JSON is correctly serialised, the templates were not re-rendering

Solution

The main issue is that getBoxComponent was serving a stale cache (componentCache) bcos it did not take into account changes in the card or field class ie cardOrField. So we added a value inside the cache storing cardOrField which then serves the most up-to-date BoxComponent if cardOrField changed.

Digression Risk

As part of pairing on Thursday with @ef4, the outer cache at fieldsComponentsFor (stableComponents) was already serving a stale cache that was preventing the code from returning the most up-to-date cache in boxComponent. This several layers of caching made it difficult to debug. We initially thought that this outer-cache was not needed.

BUT afterwards I found out that the cache was made for the purpose preventing eager re-renders that caused linksToManyComponent and containsManyComponent to re-render -- so I kept the cache in place. Here is the relevant PR #860 by @jurgenwerk. I eventually, decided to keep the cache for specific fields ie plural fields like linksToManyComponent and containsManyComponent for simplicity.. also to unblock Spec and Playground work.

I plan to pair further with @ef4 to find the best solution here.. I think the more general solution wud be to allow getBoxComponent to have better handling for plurals.

[github-actions]

Host Test Results

    1 files  ±0      1 suites  ±0   24m 19s ⏱️ +19s
792 tests +3  790 ✔️ +3  2 💤 ±0  0 ❌ ±0 
797 runs  +3  795 ✔️ +3  2 💤 ±0  0 ❌ ±0 

Results for commit a894b3d. ± Comparison against base commit 17d0250.

♻️ This comment has been updated with latest results.

[burieberry]

Is the template not rerendering when clicking the button still an issue? I tried on latest main and didn't have any issues.

[tintinthong]

Is the template not rerendering when clicking the button still an issue? I tried on latest main and didn't have any issues.

wdym. Where did u see that there was a re-render of the field? Particularly, when ur somePersonField=contains(FieldDef)

[tintinthong]

Is the template not rerendering when clicking the button still an issue? I tried on latest main and didn't have any issues.

I tried this test on main. I dont think it works

[burieberry]

Is the template not rerendering when clicking the button still an issue? I tried on latest main and didn't have any issues.

I tried this test on main. I dont think it works

Sorry ok I was able to reproduce the issue. Previously didn't see it because I was switching between formats on code mode preview. Confirm that this PR resolves it.

[tintinthong]

I think this is ready for review

The continuation of this PR. I have removed the fields proxy cache and moved the cache into the linksToManyComponent. containsMany and linksToMany examples should still have the stability they have had previously.

[tintinthong]

Its great that the change in cache introduced inside getBoxComponent (that makes cardOrField as a dependency) here fixes the re-ordering template issue seen here #2241.

Essentially, it invalidates the componentCache of the box component but that also means any component state is destroyed (without auto-save).

[ef4]

We think this is a reasonable step forward without taking on a big refactor.

It's hard to be sure this doesn't change component stability somewhere else, but we haven't been able to find any examples in the tests. So we can move ahead with this and folks should be on the lookout for any component state loss regressions that we can debug.