add associated type bounds test

Author: lcnr

src/test/ui/const-generics/associated-type-bound-fail.full.stderr

@@ -0,0 +1,15 @@
+error[E0277]: the trait bound `u16: Bar<N>` is not satisfied
+  --> $DIR/associated-type-bound-fail.rs:14:5
+   |
+LL |     type Assoc: Bar<N>;
+   |                 ------ required by this bound in `Foo::Assoc`
+...
+LL |     type Assoc = u16;
+   |     ^^^^^^^^^^^^^^^^^ the trait `Bar<N>` is not implemented for `u16`
+   |
+   = help: the following implementations were found:
+             <u16 as Bar<3_usize>>
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0277`.

src/test/ui/const-generics/associated-type-bound-fail.min.stderr

@@ -0,0 +1,15 @@
+error[E0277]: the trait bound `u16: Bar<N>` is not satisfied
+  --> $DIR/associated-type-bound-fail.rs:14:5
+   |
+LL |     type Assoc: Bar<N>;
+   |                 ------ required by this bound in `Foo::Assoc`
+...
+LL |     type Assoc = u16;
+   |     ^^^^^^^^^^^^^^^^^ the trait `Bar<N>` is not implemented for `u16`
+   |
+   = help: the following implementations were found:
+             <u16 as Bar<3_usize>>
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0277`.

src/test/ui/const-generics/associated-type-bound-fail.rs

@@ -0,0 +1,17 @@
+// revisions: full min
+#![cfg_attr(full, allow(incomplete_features))]
+#![cfg_attr(full, feature(const_generics))]
+#![cfg_attr(min, feature(min_const_generics))]
+
+trait Bar<const N: usize> {}
+
+trait Foo<const N: usize> {
+    type Assoc: Bar<N>;
+}
+
+impl Bar<3> for u16 {}
+impl<const N: usize> Foo<N> for i16 {
+    type Assoc = u16; //~ ERROR the trait bound `u16: Bar<N>`
+}
+
+fn main() {}

src/test/ui/const-generics/associated-type-bound.rs

@@ -0,0 +1,24 @@
+// run-pass
+// revisions: full min
+#![cfg_attr(full, allow(incomplete_features))]
+#![cfg_attr(full, feature(const_generics))]
+#![cfg_attr(min, feature(min_const_generics))]
+
+trait Bar<const N: usize> {}
+
+trait Foo<const N: usize> {
+    type Assoc: Bar<N>;
+}
+
+impl<const N: usize> Bar<N> for u8 {}
+impl Bar<3> for u16 {}
+
+impl<const N: usize> Foo<N> for i8 {
+    type Assoc = u8;
+}
+
+impl Foo<3> for i16 {
+    type Assoc = u16;
+}
+
+fn main() {}