Merging upstream version 1.68.2+dfsg1.

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

1 files changed, 37 insertions, 0 deletions

diff --git a/tests/ui/never_type/try_from.rs b/tests/ui/never_type/try_from.rs
new file mode 100644
index 000000000..50451576f
--- /dev/null
+++ b/tests/ui/never_type/try_from.rs
@@ -0,0 +1,37 @@
+// run-pass
+// This test relies on `TryFrom` being blanket impl for all `T: Into`
+// and `TryInto` being blanket impl for all `U: TryFrom`
+
+// This test was added to show the motivation for doing this
+// over `TryFrom` being blanket impl for all `T: From`
+
+#![feature(never_type)]
+
+use std::convert::{TryInto, Infallible};
+
+struct Foo<T> {
+    t: T,
+}
+
+// This fails to compile due to coherence restrictions
+// as of Rust version 1.32.x, therefore it could not be used
+// instead of the `Into` version of the impl, and serves as
+// motivation for a blanket impl for all `T: Into`, instead
+// of a blanket impl for all `T: From`
+/*
+impl<T> From<Foo<T>> for Box<T> {
+    fn from(foo: Foo<T>) -> Box<T> {
+        Box::new(foo.t)
+    }
+}
+*/
+
+impl<T> Into<Vec<T>> for Foo<T> {
+    fn into(self) -> Vec<T> {
+        vec![self.t]
+    }
+}
+
+pub fn main() {
+    let _: Result<Vec<i32>, Infallible> = Foo { t: 10 }.try_into();
+}