error[E0005]: refutable pattern in assignment
  --> $DIR/refutable-enum-assignment.rs:9:5
   |
LL |     Foo::One = Foo::One;
   |     ^^^^^^^^ pattern `Foo::Two` not covered
   |
   = note: destructuring assignments require an "irrefutable pattern", like a `struct` or an `enum` with only one variant
   = note: for more information, visit https://doc.rust-lang.org/book/ch19-02-refutability.html
note: `Foo` defined here
  --> $DIR/refutable-enum-assignment.rs:3:6
   |
LL | enum Foo {
   |      ^^^
LL |     One,
LL |     Two,
   |     --- not covered
   = note: the matched value is of type `Foo`

error: aborting due to 1 previous error

For more information about this error, try `rustc --explain E0005`.