fix: async cache storing exception fixed

[akmalviya03]

Earlier async cache was caching exceptions.
With new changes in fetch method of AsyncCache class will no longer store exception.
By default AsyncCache will store exception, by setting _canCacheException to false. It won't store exception.

Please refer #366 for video demo of both issue and solution along with minimal reproducible code.

---

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[lrhn]

Any naming we can use that would make the flag default to false?
Just because it's usually a good idea to have false as the default value.

Maybe bool ephemeralErrors = false. (Ouch, would hate to have to write that).
flushErrors?

[akmalviya03]

What about discardErrors?

[lrhn]

The _cacheErrors here feels like it should be false (since it doesn't cache errors, because it doesn't cache anything). It's invisible to the user, so it doesn't really matter, and I guess it just means "don't special-case errors".
It's OK, just a little confusing.

I guess there are really three modes:

• Ephemeral everything.
• Ephemeral errors, persistent values.
• Persistent everything.

covered by two constructors. Should we just have three constructors?

[lrhn]

Consider checking that time hasn't progressed by one hour. Just for good measure.

[akmalviya03]

Done updated test cases.

[lrhn]

Not sure "fetch" is the verb I'd use here (aka: I don't know what the description means).
It's consistent with the other tests. I also can't read those.

That's not really your issue to fix, though. (Should we say "recompute" instead of "fetch". Why is the method called fetch to begin with, seems to assume a specific use-case.)

[akmalviya03]

Initially I also thought the same, to rename it to something more generic.

[github-actions]

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[mosuem]

@lrhn i think it's your turn for the review ;) Just a friendly ping!

[mosuem]

@lrhn any more comments? Otherwise I would merge this.

[akmalviya03]

Hi guys, how should I proceed with future PRs. So, that it won't take much time to merge.

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[mosuem]

Hi, I think it's just an issue of the team having a full plate - sorry about that!