TypeComparer: delay looking up members of AndTypes

In ParFactory.scala we have checks that look like:
  (Foo { type Bar = X }) & (Foo { type Bar = X }) <:< (Foo { type Bar = X })
where `Foo` is a recursive type.

Before this commit, we would first try to check this by looking up `Bar`
in the `AndType` on the left, which means looking it up in both branches
and then merging the result, but the merge requires more subtyping
checks, which in turn require looking up a member inside an `AndType`,
seemingly ad infinitum.

We now avoid this by checking if either branch of the `AndType` on the left
is a subtype of the `RefinedType` on the right before looking up a member
in the `AndType` itself.

0 files changed, 0 insertions, 0 deletions