Merging upstream version 1.68.2+dfsg1.

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

1 files changed, 54 insertions, 0 deletions

diff --git a/tests/ui/closures/2229_closure_analysis/run_pass/mut_ref.rs b/tests/ui/closures/2229_closure_analysis/run_pass/mut_ref.rs
new file mode 100644
index 000000000..9f0c4d96a
--- /dev/null
+++ b/tests/ui/closures/2229_closure_analysis/run_pass/mut_ref.rs
@@ -0,0 +1,54 @@
+// edition:2021
+// run-pass
+
+// Test that we can mutate a place through a mut-borrow
+// that is captured by the closure
+
+// Check that we can mutate when one deref is required
+fn mut_ref_1() {
+    let mut x = String::new();
+    let rx = &mut x;
+
+    let mut c = || {
+        *rx = String::new();
+    };
+
+    c();
+}
+
+// Similar example as mut_ref_1, we don't deref the imm-borrow here,
+// and so we are allowed to mutate.
+fn mut_ref_2() {
+    let x = String::new();
+    let y = String::new();
+    let mut ref_x = &x;
+    let m_ref_x = &mut ref_x;
+
+    let mut c = || {
+        *m_ref_x = &y;
+    };
+
+    c();
+}
+
+// Check that we can mutate when multiple derefs of mut-borrows are required to reach
+// the target place.
+// It works because all derefs are mutable, if either of them was an immutable
+// borrow, then we would not be able to deref.
+fn mut_mut_ref() {
+    let mut x = String::new();
+    let mut mref_x = &mut x;
+    let m_mref_x = &mut mref_x;
+
+    let mut c = || {
+        **m_mref_x = String::new();
+    };
+
+    c();
+}
+
+fn main() {
+    mut_ref_1();
+    mut_ref_2();
+    mut_mut_ref();
+}