1 files changed, 53 insertions, 0 deletions
diff --git a/tests/coverage/auto-derived.rs b/tests/coverage/auto-derived.rs
new file mode 100644
index 00000000000..cbf8279918a
--- /dev/null
+++ b/tests/coverage/auto-derived.rs
@@ -0,0 +1,53 @@
+#![feature(coverage_attribute)]
+//@ edition: 2024
+//@ revisions: base auto on
+
+// Tests for how `#[automatically_derived]` affects coverage instrumentation.
+//
+// The actual behaviour is an implementation detail, so this test mostly exists
+// to show when that behaviour has been accidentally or deliberately changed.
+//
+// Revision guide:
+// - base: Test baseline instrumentation behaviour without `#[automatically_derived]`
+// - auto: Test how `#[automatically_derived]` affects instrumentation
+// - on:   Test interaction between auto-derived and `#[coverage(on)]`
+
+struct MyStruct;
+
+trait MyTrait {
+    fn my_assoc_fn();
+}
+
+#[cfg_attr(auto, automatically_derived)]
+#[cfg_attr(on, automatically_derived)]
+#[cfg_attr(on, coverage(on))]
+impl MyTrait for MyStruct {
+    fn my_assoc_fn() {
+        fn inner_fn() {
+            say("in inner fn");
+        }
+
+        #[coverage(on)]
+        fn inner_fn_on() {
+            say("in inner fn (on)");
+        }
+
+        let closure = || {
+            say("in closure");
+        };
+
+        closure();
+        inner_fn();
+        inner_fn_on();
+    }
+}
+
+#[coverage(off)]
+#[inline(never)]
+fn say(s: &str) {
+    println!("{s}");
+}
+
+fn main() {
+    MyStruct::my_assoc_fn();
+}