Allow non-rust idents column names in SerializeRow derived struct

fixes cases where the "column name" is not a valid rust identifier;
such as trying to pass in a dynamic TTL

Author: nrxus

scylla-cql/src/types/serialize/row.rs

@@ -1568,6 +1568,23 @@ pub(crate) mod tests {
         assert_eq!(reference, row);
     }
 
+    #[test]
+    fn test_row_serialization_with_not_rust_idents() {
+        #[derive(SerializeRow, Debug)]
+        #[scylla(crate = crate)]
+        struct RowWithTTL {
+            #[scylla(rename = "[ttl]")]
+            ttl: i32,
+        }
+
+        let spec = [col("[ttl]", ColumnType::Int)];
+
+        let reference = do_serialize((42i32,), &spec);
+        let row = do_serialize(RowWithTTL { ttl: 42 }, &spec);
+
+        assert_eq!(reference, row);
+    }
+
     #[derive(SerializeRow, Debug)]
     #[scylla(crate = crate)]
     struct TestRowWithSkippedFields {

scylla-macros/src/serialize/row.rs

@@ -223,7 +223,7 @@ impl Generator for ColumnSortingGenerator<'_> {
         statements.push(self.ctx.generate_mk_ser_err());
 
         // Generate a "visited" flag for each field
-        let visited_flag_names = rust_field_names
+        let visited_flag_names = rust_field_idents
             .iter()
             .map(|s| syn::Ident::new(&format!("visited_flag_{}", s), Span::call_site()))
             .collect::<Vec<_>>();