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authorAlbert Larsan <74931857+albertlarsan68@users.noreply.github.com>2023-01-05 09:13:28 +0100
committerAlbert Larsan <74931857+albertlarsan68@users.noreply.github.com>2023-01-11 09:32:08 +0000
commitcf2dff2b1e3fa55fa5415d524200070d0d7aacfe (patch)
tree40a88d9a46aaf3e8870676eb2538378b75a263eb /tests/ui/rfc-2632-const-trait-impl/specialization/non-const-default-const-specialized.rs
parentca855e6e42787ecd062d81d53336fe6788ef51a9 (diff)
downloadrust-cf2dff2b1e3fa55fa5415d524200070d0d7aacfe.tar.gz
rust-cf2dff2b1e3fa55fa5415d524200070d0d7aacfe.zip
Move /src/test to /tests
Diffstat (limited to 'tests/ui/rfc-2632-const-trait-impl/specialization/non-const-default-const-specialized.rs')
-rw-r--r--tests/ui/rfc-2632-const-trait-impl/specialization/non-const-default-const-specialized.rs39
1 files changed, 39 insertions, 0 deletions
diff --git a/tests/ui/rfc-2632-const-trait-impl/specialization/non-const-default-const-specialized.rs b/tests/ui/rfc-2632-const-trait-impl/specialization/non-const-default-const-specialized.rs
new file mode 100644
index 00000000000..35aa52fbd4e
--- /dev/null
+++ b/tests/ui/rfc-2632-const-trait-impl/specialization/non-const-default-const-specialized.rs
@@ -0,0 +1,39 @@
+// Tests that a non-const default impl can be specialized by a const trait impl,
+// but that the default impl cannot be used in a const context.
+
+// run-pass
+
+#![feature(const_trait_impl)]
+#![feature(min_specialization)]
+
+#[const_trait]
+trait Value {
+    fn value() -> u32;
+}
+
+const fn get_value<T: ~const Value>() -> u32 {
+    T::value()
+}
+
+impl<T> Value for T {
+    default fn value() -> u32 {
+        println!("You can't do that (constly)");
+        0
+    }
+}
+
+struct FortyTwo;
+
+impl const Value for FortyTwo {
+    fn value() -> u32 {
+        42
+    }
+}
+
+fn main() {
+    let zero = get_value::<()>();
+    assert_eq!(zero, 0);
+
+    const FORTY_TWO: u32 = get_value::<FortyTwo>();
+    assert_eq!(FORTY_TWO, 42);
+}