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, 36 insertions, 0 deletions

diff --git a/src/test/ui/nll/closure-requirements/issue-58127-mutliple-requirements.rs b/src/test/ui/nll/closure-requirements/issue-58127-mutliple-requirements.rs
new file mode 100644
index 000000000..a83ebc21f
--- /dev/null
+++ b/src/test/ui/nll/closure-requirements/issue-58127-mutliple-requirements.rs
@@ -0,0 +1,36 @@
+// check-pass
+
+// Test that we propagate region relations from closures precisely when there is
+// more than one non-local lower bound.
+
+// In this case the closure has signature
+// |x: &'4 mut (&'5 (&'1 str, &'2 str), &'3 str)| -> ..
+// We end up with a `'3: '5` constraint that we can propagate as
+// `'3: '1`, `'3: '2`, but previously we approximated it as `'3: 'static`.
+
+// As an optimization, we primarily propagate bounds for the "representative"
+// of each SCC. As such we have these two similar cases where hopefully one
+// of them will test the case we want (case2, when this test was added).
+mod case1 {
+    fn f(s: &str) {
+        g(s, |x| h(x));
+    }
+
+    fn g<T, F>(_: T, _: F)
+    where F: Fn(&mut (&(T, T), T)) {}
+
+    fn h<T>(_: &mut (&(T, T), T)) {}
+}
+
+mod case2 {
+    fn f(s: &str) {
+        g(s, |x| h(x));
+    }
+
+    fn g<T, F>(_: T, _: F)
+    where F: Fn(&mut (T, &(T, T))) {}
+
+    fn h<T>(_: &mut (T, &(T, T))) {}
+}
+
+fn main() {}