Enforce explicit Some around raw values (#494)

Author: juntyr

src/ser/mod.rs

@@ -842,7 +842,20 @@ impl<'a, W: io::Write> ser::Serializer for &'a mut Serializer<W> {
         T: ?Sized + Serialize,
     {
         if name == crate::value::raw::RAW_VALUE_TOKEN {
-            return guard_recursion! { self => value.serialize(raw::RawValueSerializer::new(self)) };
+            let implicit_some_depth = self.implicit_some_depth;
+            self.implicit_some_depth = 0;
+
+            for _ in 0..implicit_some_depth {
+                self.output.write_all(b"Some(")?;
+            }
+
+            guard_recursion! { self => value.serialize(raw::RawValueSerializer::new(self)) }?;
+
+            for _ in 0..implicit_some_depth {
+                self.output.write_all(b")")?;
+            }
+
+            return Ok(());
         }
 
         if self.extensions().contains(Extensions::UNWRAP_NEWTYPES) || self.newtype_variant {

tests/407_raw_value.rs

@@ -306,4 +306,21 @@ fn test_fuzzer_found_issue() {
         ron::from_str::<&RawValue>("a").unwrap(),
         RawValue::from_ron("a").unwrap()
     );
+
+    assert_eq!(
+        ron::to_string(&Some(Some(RawValue::from_ron("None").unwrap()))).unwrap(),
+        "Some(Some(None))"
+    );
+    // Since a RawValue can contain anything, no implicit Some are allowed around it
+    assert_eq!(
+        ron::Options::default()
+            .with_default_extension(ron::extensions::Extensions::IMPLICIT_SOME)
+            .to_string(&Some(Some(RawValue::from_ron("None").unwrap())))
+            .unwrap(),
+        "Some(Some(None))"
+    );
+    assert_eq!(
+        ron::from_str::<Option<Option<&RawValue>>>("Some(Some(None))").unwrap(),
+        Some(Some(RawValue::from_ron("None").unwrap()))
+    );
 }