Adding upstream version 1.64.0+dfsg1.upstream/1.64.0+dfsg1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 24 insertions, 0 deletions

diff --git a/src/test/ui/traits/negative-impls/rely-on-negative-impl-in-coherence.rs b/src/test/ui/traits/negative-impls/rely-on-negative-impl-in-coherence.rs
new file mode 100644
index 000000000..c1f96ab8c
--- /dev/null
+++ b/src/test/ui/traits/negative-impls/rely-on-negative-impl-in-coherence.rs
@@ -0,0 +1,24 @@
+// check-pass
+
+#![feature(negative_impls)]
+#![feature(with_negative_coherence)]
+
+// aux-build: foreign_trait.rs
+
+// Test that we cannot implement `LocalTrait` for `String`,
+// even though there is a `String: !ForeignTrait` impl.
+//
+// This may not be the behavior we want long term, but it's the
+// current semantics that we implemented so as to land `!Foo` impls
+// quickly. See internals thread:
+//
+// https://internals.rust-lang.org/t/foo/11587/
+
+extern crate foreign_trait;
+use foreign_trait::ForeignTrait;
+
+trait LocalTrait {}
+impl<T: ForeignTrait> LocalTrait for T {}
+impl LocalTrait for String {}
+
+fn main() {}