1 files changed, 63 insertions, 0 deletions
diff --git a/src/test/ui/rfc-2632-const-trait-impl/staged-api.rs b/src/test/ui/rfc-2632-const-trait-impl/staged-api.rs
new file mode 100644
index 000000000..1d79f5adf
--- /dev/null
+++ b/src/test/ui/rfc-2632-const-trait-impl/staged-api.rs
@@ -0,0 +1,63 @@
+// revisions: stable unstable
+
+#![cfg_attr(unstable, feature(unstable))] // The feature from the ./auxiliary/staged-api.rs file.
+#![feature(const_trait_impl)]
+#![feature(staged_api)]
+#![stable(feature = "rust1", since = "1.0.0")]
+
+// aux-build: staged-api.rs
+extern crate staged_api;
+
+use staged_api::*;
+
+#[stable(feature = "rust1", since = "1.0.0")]
+pub struct Foo;
+
+#[stable(feature = "rust1", since = "1.0.0")]
+#[cfg_attr(unstable, rustc_const_unstable(feature = "foo", issue = "none"))]
+#[cfg_attr(stable, rustc_const_stable(feature = "foo", since = "1.0.0"))]
+impl const MyTrait for Foo {
+    //[stable]~^ ERROR trait implementations cannot be const stable yet
+    fn func() {}
+}
+
+// Const stability has no impact on usage in non-const contexts.
+fn non_const_context() {
+    Unstable::func();
+    Foo::func();
+}
+
+#[unstable(feature = "none", issue = "none")]
+const fn const_context() {
+    Unstable::func();
+    // ^ This is okay regardless of whether the `unstable` feature is enabled, as this function is
+    // not const-stable.
+    Foo::func();
+    //[unstable]~^ ERROR not yet stable as a const fn
+    // ^ fails, because the `foo` feature is not active
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+#[cfg_attr(unstable, rustc_const_unstable(feature = "foo", issue = "none"))]
+pub const fn const_context_not_const_stable() {
+    //[stable]~^ ERROR function has missing const stability attribute
+    Unstable::func();
+    // ^ This is okay regardless of whether the `unstable` feature is enabled, as this function is
+    // not const-stable.
+    Foo::func();
+    //[unstable]~^ ERROR not yet stable as a const fn
+    // ^ fails, because the `foo` feature is not active
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+#[rustc_const_stable(feature = "cheese", since = "1.0.0")]
+const fn stable_const_context() {
+    Unstable::func();
+    //[unstable]~^ ERROR not yet stable as a const fn
+    Foo::func();
+    //[unstable]~^ ERROR not yet stable as a const fn
+    const_context_not_const_stable()
+    //[unstable]~^ ERROR not yet stable as a const fn
+}
+
+fn main() {}