Try #229:

Author: bors[bot]

godot-core/src/builtin/array.rs

@@ -883,12 +883,7 @@ struct TypeInfo {
 impl TypeInfo {
     fn new<T: VariantMetadata>() -> Self {
         let variant_type = T::variant_type();
-        let class_name = match variant_type {
-            VariantType::Object => StringName::from(T::class_name()),
-            // TODO for variant types other than Object, class_name() returns "(no base)"; just
-            // make it return "" instead?
-            _ => StringName::default(),
-        };
+        let class_name: StringName = T::class_name().unwrap_or_default().into();
         Self {
             variant_type,
             class_name,

godot-core/src/builtin/meta/class_name.rs

@@ -13,7 +13,7 @@ use crate::obj::GodotClass;
 
 /// Utility to construct class names known at compile time.
 /// Cannot be a function since the backing string must be retained.
-#[derive(Eq, PartialEq, Hash, Clone, Debug)]
+#[derive(Default, Eq, PartialEq, Hash, Clone, Debug)]
 pub struct ClassName {
     backing: StringName,
 }

godot-core/src/builtin/meta/mod.rs

@@ -22,14 +22,15 @@ use godot_ffi as sys;
 pub trait VariantMetadata {
     fn variant_type() -> VariantType;
 
-    fn class_name() -> ClassName {
-        ClassName::of::<()>() // FIXME Option or so
+    fn class_name() -> Option<ClassName> {
+        // If we use `ClassName::of::<()>()` then this type shows up as `(no base)` in documentation.
+        None
     }
 
     fn property_info(property_name: &str) -> PropertyInfo {
         PropertyInfo {
             variant_type: Self::variant_type(),
-            class_name: Self::class_name(),
+            class_name: Self::class_name().unwrap_or_default(),
             property_name: StringName::from(property_name),
             hint: global::PropertyHint::PROPERTY_HINT_NONE,
             hint_string: GodotString::new(),

godot-core/src/builtin/variant/impls.rs

@@ -229,7 +229,7 @@ impl VariantMetadata for Variant {
     fn property_info(property_name: &str) -> PropertyInfo {
         PropertyInfo {
             variant_type: Self::variant_type(),
-            class_name: Self::class_name(),
+            class_name: Self::class_name().unwrap_or_default(),
             property_name: StringName::from(property_name),
             hint: global::PropertyHint::PROPERTY_HINT_NONE,
             hint_string: GodotString::new(),

godot-core/src/obj/gd.rs

@@ -709,8 +709,8 @@ impl<T: GodotClass> VariantMetadata for Gd<T> {
         VariantType::Object
     }
 
-    fn class_name() -> ClassName {
-        ClassName::of::<T>()
+    fn class_name() -> Option<ClassName> {
+        Some(ClassName::of::<T>())
     }
 }