Addes test case for !Send + !Sync

tests/no_send_sync.rs

@@ -0,0 +1,35 @@
+#[macro_use]
+extern crate salsa;
+
+use std::rc::Rc;
+
+// #[derive(Clone, PartialEq, Eq, Debug)]
+// struct Dummy;
+
+#[salsa::query_group(NoSendStorage)]
+trait NoSendDatabase: salsa::Database {
+    fn query(&self, key: ()) -> Rc<bool>;
+}
+
+fn query(db: &impl NoSendDatabase, (): ()) -> Rc<bool> {
+    Rc::new(true)
+}
+
+#[salsa::database(NoSendStorage)]
+#[derive(Default)]
+struct DatabaseImpl {
+    runtime: salsa::Runtime<DatabaseImpl>,
+}
+
+impl salsa::Database for DatabaseImpl {
+    fn salsa_runtime(&self) -> &salsa::Runtime<DatabaseImpl> {
+        &self.runtime
+    }
+}
+
+#[test]
+fn no_send_sync() {
+    let mut db = DatabaseImpl::default();
+
+    db.query(());
+}