add tests for fixed issues

Author: adwinwhite

tests/ui/traits/next-solver/dont-ice-on-normalization-failure.rs

@@ -0,0 +1,22 @@
+//@compile-flags: -Znext-solver
+
+// Regression test for #151308
+
+#![feature(lazy_type_alias)]
+trait Trait {
+    type Associated;
+}
+
+trait Generic<T> {}
+
+type TraitObject = dyn Generic<<i32 as Trait>::Associated>;
+//~^ ERROR: the trait bound `i32: Trait` is not satisfied
+
+struct Wrap(TraitObject);
+//~^ ERROR: the trait bound `i32: Trait` is not satisfied
+
+fn cast(x: *mut Wrap) {
+    x as *mut Wrap;
+}
+
+fn main() {}

tests/ui/traits/next-solver/dont-ice-on-normalization-failure.stderr

@@ -0,0 +1,27 @@
+error[E0277]: the trait bound `i32: Trait` is not satisfied
+  --> $DIR/dont-ice-on-normalization-failure.rs:12:32
+   |
+LL | type TraitObject = dyn Generic<<i32 as Trait>::Associated>;
+   |                                ^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `Trait` is not implemented for `i32`
+   |
+help: this trait has no implementations, consider adding one
+  --> $DIR/dont-ice-on-normalization-failure.rs:6:1
+   |
+LL | trait Trait {
+   | ^^^^^^^^^^^
+
+error[E0277]: the trait bound `i32: Trait` is not satisfied
+  --> $DIR/dont-ice-on-normalization-failure.rs:15:13
+   |
+LL | struct Wrap(TraitObject);
+   |             ^^^^^^^^^^^ the trait `Trait` is not implemented for `i32`
+   |
+help: this trait has no implementations, consider adding one
+  --> $DIR/dont-ice-on-normalization-failure.rs:6:1
+   |
+LL | trait Trait {
+   | ^^^^^^^^^^^
+
+error: aborting due to 2 previous errors
+
+For more information about this error, try `rustc --explain E0277`.

tests/ui/traits/next-solver/self-referential-closure-sig-1.rs

@@ -0,0 +1,23 @@
+//@compile-flags: -Znext-solver
+//@check-pass
+
+// Regression test for the first variant of trait-system-refactor-initiative#191
+
+trait Indir<T>: FnOnce(T) -> Self::Ret {
+    type Ret;
+}
+impl<F, T, R> Indir<T> for F where F: FnOnce(T) -> R {
+    type Ret = R;
+}
+
+trait Mirror {
+    type Assoc<'a>;
+}
+
+fn needs<T: Mirror>(_: impl for<'a> Indir<T::Assoc<'a>>) {}
+
+fn test<T>() where for<'a> T: Mirror<Assoc<'a> = i32> {
+    needs::<T>(|x| { x.to_string(); });
+}
+
+fn main() {}