Adapter instances should be destroyed

[rwjblue]

It appears that adapter instances are never being destroyed.

Related codepaths:

We configure the adapter type to be non-singleton here:

data/packages/-ember-data/addon/setup-container.js

Line 37 in 005ff4d

application.registerOptionsForType('adapter', { singleton: false });

And then we instantiate the adapter instances with owner.lookup here:

data/packages/store/addon/-private/system/core-store.ts

Line 3254 in 005ff4d

adapter = owner.lookup(`adapter:${normalizedModelName}`);

But in the store's willDestroy we do nothing with this._adapterCache (we should loop over them and be calling .destroy())

data/packages/store/addon/-private/system/core-store.ts

Line 3490 in 005ff4d

willDestroy() {

---

This is generally not an issue for most users, as they are not commonly doing their own async from within the adapter instances. However, as soon as you attempt to do things like tracking response info (by queueing and firing a request) or doing exponential backoff you might find yourself in a situation where you need to clean up a timer (clearTimeout, runDestroyables, etc). Since we never run adapterInstance.destroy(), the user can't implement willDestroy and have that cleanup code be ran (ember-concurrency and ember-lifeline both leverage .destroy() being called in order to properly cleanup).

[rwjblue]

FWIW, this was introduced in #5305 (and has been an issue throughout the entire 3.x series).