Added trybuild test for references inside uncased instances

Author: vigna

epserde/tests/fail/drop_memcase_and_get.rs

@@ -0,0 +1,21 @@
+/*
+ * SPDX-FileCopyrightText: 2025 Sebastiano Vigna
+ *
+ * SPDX-License-Identifier: Apache-2.0 OR LGPL-2.1-or-later
+ */
+
+use epserde::prelude::*;
+use std::io::Cursor;
+
+fn main() {
+    let vec = vec!["foo".to_string(), "bar".to_string(), "baz".to_string()];
+
+    let mut buffer = Vec::new();
+    unsafe { vec.serialize(&mut buffer).unwrap() };
+    let cursor = Cursor::new(&buffer);
+    let mem_case = unsafe { <Vec<String>>::read_mem(cursor, buffer.len()).unwrap() };
+
+    let s = mem_case.uncase().get(0);
+    drop(mem_case);
+    assert_eq!(s, Some(&"foo"));
+}

epserde/tests/fail/drop_memcase_and_get.stderr

@@ -0,0 +1,12 @@
+error[E0505]: cannot move out of `mem_case` because it is borrowed
+  --> tests/fail/drop_memcase_and_get.rs:19:10
+   |
+16 |     let mem_case = unsafe { <Vec<String>>::read_mem(cursor, buffer.len()).unwrap() };
+   |         -------- binding `mem_case` declared here
+17 |
+18 |     let s = mem_case.uncase().get(0);
+   |             -------- borrow of `mem_case` occurs here
+19 |     drop(mem_case);
+   |          ^^^^^^^^ move out of `mem_case` occurs here
+20 |     assert_eq!(s, Some(&"foo"));
+   |     --------------------------- borrow later used here