Cover ContentRefDeserializer::deserialize_option

2026-06-19 18:01:05 +00:00 · 2024-08-17 11:58:28 +05:00
parent 8514f4119a
commit 2dddc7796d
2 changed files with 81 additions and 0 deletions
@@ -1898,10 +1898,17 @@ mod content {
        where
            V: Visitor<'de>,
        {
+            // Covered by tests/test_enum_untagged.rs
+            //      with_optional_field::*
            match *self.content {
                Content::None => visitor.visit_none(),
                Content::Some(ref v) => visitor.visit_some(ContentRefDeserializer::new(v)),
                Content::Unit => visitor.visit_unit(),
+                // This case is necessary for formats which does not store marker of optionality of value,
+                // for example, JSON. When `deserialize_any` is requested from such formats, they will
+                // report value without using `Visitor::visit_some`, because they do not known in which
+                // contexts this value will be used.
+                // RON is example of format which preserve markers.
                _ => visitor.visit_some(self),
            }
        }