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Diffstat (limited to '')
-rw-r--r-- | tests/ui/traits/new-solver/provisional-result-done.rs | 33 |
1 files changed, 33 insertions, 0 deletions
diff --git a/tests/ui/traits/new-solver/provisional-result-done.rs b/tests/ui/traits/new-solver/provisional-result-done.rs new file mode 100644 index 000000000..589d34dd7 --- /dev/null +++ b/tests/ui/traits/new-solver/provisional-result-done.rs @@ -0,0 +1,33 @@ +// compile-flags: -Ztrait-solver=next +// check-pass + +// This tests checks that we update results in the provisional cache when +// we pop a goal from the stack. +#![feature(auto_traits)] +auto trait Coinductive {} +struct Foo<T>(T); +struct Bar<T>(T); + +impl<T> Coinductive for Foo<T> +where + Bar<T>: Coinductive +{} + +impl<T> Coinductive for Bar<T> +where + Foo<T>: Coinductive, + Bar<T>: ConstrainInfer, +{} + +trait ConstrainInfer {} +impl ConstrainInfer for Bar<u8> {} +impl ConstrainInfer for Foo<u16> {} + +fn impls<T: Coinductive>() -> T { todo!() } + +fn constrain<T: ConstrainInfer>(_: T) {} + +fn main() { + // This should constrain `_` to `u8`. + impls::<Foo<_>>(); +} |