1 files changed, 27 insertions, 0 deletions
diff --git a/src/test/ui/defaults-well-formedness.rs b/src/test/ui/defaults-well-formedness.rs
new file mode 100644
index 000000000..327589061
--- /dev/null
+++ b/src/test/ui/defaults-well-formedness.rs
@@ -0,0 +1,27 @@
+// run-pass
+
+#![allow(dead_code)]
+trait Trait<T> {}
+struct Foo<U, V=i32>(U, V) where U: Trait<V>;
+
+trait Marker {}
+struct TwoParams<T, U>(T, U);
+impl Marker for TwoParams<i32, i32> {}
+
+// Clauses with more than 1 param are not checked.
+struct IndividuallyBogus<T = i32, U = i32>(TwoParams<T, U>) where TwoParams<T, U>: Marker;
+struct BogusTogether<T = u32, U = i32>(T, U) where TwoParams<T, U>: Marker;
+// Clauses with non-defaulted params are not checked.
+struct NonDefaultedInClause<T, U = i32>(TwoParams<T, U>) where TwoParams<T, U>: Marker;
+struct DefaultedLhs<U, V=i32>(U, V) where V: Trait<U>;
+// Dependent defaults are not checked.
+struct Dependent<T, U = T>(T, U) where U: Copy;
+trait SelfBound<T: Copy=Self> {}
+// Not even for well-formedness.
+struct WellFormedProjection<A, T=<A as Iterator>::Item>(A, T);
+
+// Issue #49344, predicates with lifetimes should not be checked.
+trait Scope<'a> {}
+struct Request<'a, S: Scope<'a> = i32>(S, &'a ());
+
+fn main() {}