Small poc of little ecto bug found
mix deps.get && mix compile
mix ecto.create
mix ecto.migrate
iex -S mix run -e "EctoBug.replicate"
Expected result: update on conflict successful since posts
is not in the changeset
Actual result
** (RuntimeError) attempting to cast or change association `posts` from `EctoBug.Schema.Author` that was not loaded. Please preload your associations before manipulating them through changesets
Some of them work, some replicate the bug. Seems the fetching of the row is the discriminant
iex -S mix run -e "EctoBug.replicate(:two)"
iex -S mix run -e "EctoBug.replicate(:three)"
iex -S mix run -e "EctoBug.replicate(:four)"