error[E0658]: associated type bounds are unstable
  --> $DIR/missing-assoc-fn.rs:9:22
   |
LL |     fn bat<T: TraitB<Item: Copy>>(_: T) -> Self;
   |                      ^^^^^^^^^^
   |
   = note: see issue #52662 <https://github.com/rust-lang/rust/issues/52662> for more information
   = help: add `#![feature(associated_type_bounds)]` to the crate attributes to enable

error[E0046]: not all trait items implemented, missing: `foo`, `bar`, `baz`, `bat`
  --> $DIR/missing-assoc-fn.rs:14:1
   |
LL |     fn foo<T: TraitB<Item = A>>(_: T) -> Self;
   |     ------------------------------------------ `foo` from trait
LL |     fn bar<T>(_: T) -> Self;
   |     ------------------------ `bar` from trait
LL |     fn baz<T>(_: T) -> Self where T: TraitB, <T as TraitB>::Item: Copy;
   |     ------------------------------------------------------------------- `baz` from trait
LL |     fn bat<T: TraitB<Item: Copy>>(_: T) -> Self;
   |     -------------------------------------------- `bat` from trait
...
LL | impl TraitA<()> for S {
   | ^^^^^^^^^^^^^^^^^^^^^ missing `foo`, `bar`, `baz`, `bat` in implementation

error[E0046]: not all trait items implemented, missing: `from_iter`
  --> $DIR/missing-assoc-fn.rs:19:1
   |
LL | impl FromIterator<()> for X {
   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^ missing `from_iter` in implementation
   |
   = help: implement the missing item: `fn from_iter<T>(_: T) -> Self where T: IntoIterator, std::iter::IntoIterator::Item = () { todo!() }`

error: aborting due to 3 previous errors

Some errors have detailed explanations: E0046, E0658.
For more information about an error, try `rustc --explain E0046`.