Cache busting doesn't bubble up in some cases without eagerloading

Given the following classes:

class A < AR::Base
  has_many :bs, inverse: :a
  cache_has_many(:bs, embed: true)
end

class B < AR::Base
  belongs_to :a, inverse: :bs

  has_one :c
  cache_has_one(:c, embed: true)
end

class C < AR::Base
  has_many :b, inverse: :c
end

when saving an instance of C, B gets removed from the cache, but not A. Thus, B#fetch_c returns the latest version but A#fetch_bs return a stale collection.

I could reproduce this scenario as a failing test: https://github.com/Shopify/identity_cache/compare/ancestor-invalidation-failing

Am I missing something or is this a bug?

Start with the failing test in the ancestor-invalidation-failing comparison linked in the issue, using the A, B, and C association setup as the reproducer. Trace cache invalidation after saving C and compare B#fetch_c with A#fetch_bs. Done means saving C invalidates the cached collection returned by A#fetch_bs without requiring eager loading.