Adding upstream version 1.68.2+dfsg1.upstream/1.68.2+dfsg1

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

1 files changed, 27 insertions, 0 deletions

diff --git a/tests/ui/regions/regions-variance-contravariant-use-covariant.rs b/tests/ui/regions/regions-variance-contravariant-use-covariant.rs
new file mode 100644
index 000000000..c73577cb3
--- /dev/null
+++ b/tests/ui/regions/regions-variance-contravariant-use-covariant.rs
@@ -0,0 +1,27 @@
+// Test that a type which is covariant with respect to its region
+// parameter yields an error when used in a contravariant way.
+//
+// Note: see variance-regions-*.rs for the tests that check that the
+// variance inference works in the first place.
+
+// This is contravariant with respect to 'a, meaning that
+// Contravariant<'long> <: Contravariant<'short> iff
+// 'short <= 'long
+struct Contravariant<'a> {
+    f: &'a isize
+}
+
+fn use_<'short,'long>(c: Contravariant<'short>,
+                      s: &'short isize,
+                      l: &'long isize,
+                      _where:Option<&'short &'long ()>) {
+
+    // Test whether Contravariant<'short> <: Contravariant<'long>.  Since
+    // 'short <= 'long, this would be true if the Contravariant type were
+    // covariant with respect to its parameter 'a.
+
+    let _: Contravariant<'long> = c;
+    //~^ ERROR lifetime may not live long enough
+}
+
+fn main() {}