Merge #743

743: serde support for core types & VariantDispatch r=Bromeon a=Waridley

I got curious about how hard it would be to add serde support, and ended up basically fully implementing it so I figured I should start a PR 😂

There are no tests yet, and honestly I haven't really even tested it in my own project yet. I'll be doing so over the next few days probably, but for now I'll open this as a draft to allow for comments, feedback, and opinions.

The implementations for `Object` types is a bit hacky, but I really like the idea of being able to replace Godot's resource files with something more Rust-y. Since I had to wrap the references in newtypes, I suppose they could be part of a separate crate anyway, unless anyone has a better idea of how to get around the orphan rules. Even if we can implement serde's traits directly on `gdnative_core` types, there should probably be some discussion about whether it's actually desirable to skip properties that are set to their defaults (this would end up serializing a **LOT** of properties otherwise).

Would close #9 

Co-authored-by: Waridley <[email protected]>

Author: bors[bot]

gdnative-core/Cargo.toml

@@ -24,6 +24,7 @@ glam = "0.18.0"
 indexmap = "1.7.0"
 ahash = "0.7.4"
 once_cell = "1.8.0"
+serde = { version = "1", features = ["derive"], optional = true }
 
 gdnative-impl-proc-macros = { path = "../impl/proc_macros", version = "=0.9.3" }
 

gdnative-core/src/core_types/color.rs

@@ -6,6 +6,7 @@ use crate::core_types::GodotString;
 /// RGBA color with 32 bits floating point components.
 #[repr(C)]
 #[derive(Copy, Clone, Debug, PartialEq)]
+#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
 pub struct Color {
     pub r: f32,
     pub g: f32,

gdnative-core/src/core_types/error.rs

@@ -2,6 +2,7 @@ use crate::sys;
 
 /// Error codes used in various Godot APIs.
 #[derive(Copy, Clone, Debug, PartialEq, Eq)]
+#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
 #[repr(u32)]
 pub enum GodotError {
     Failed = sys::godot_error_GODOT_FAILED as u32,

gdnative-core/src/core_types/geom/aabb.rs

@@ -3,6 +3,7 @@ use crate::core_types::Vector3;
 /// Axis-aligned bounding box.
 #[repr(C)]
 #[derive(Copy, Clone, Debug, PartialEq)]
+#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
 pub struct Aabb {
     pub position: Vector3,
     pub size: Vector3,

gdnative-core/src/core_types/geom/basis.rs

@@ -5,6 +5,7 @@ use glam::Mat3;
 /// A 3x3 matrix.
 #[repr(C)]
 #[derive(Copy, Clone, Debug, PartialEq)]
+#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
 pub struct Basis {
     pub elements: [Vector3; 3],
 }

gdnative-core/src/core_types/geom/plane.rs

@@ -3,6 +3,7 @@ use crate::core_types::{IsEqualApprox, Vector3};
 /// Plane in hessian form.
 #[repr(C)]
 #[derive(Copy, Clone, Debug, PartialEq)]
+#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
 pub struct Plane {
     pub normal: Vector3,
     pub d: f32,

gdnative-core/src/core_types/geom/transform.rs

@@ -3,6 +3,7 @@ use crate::core_types::{Basis, Vector3};
 /// 3D Transformation (3x4 matrix) Using basis + origin representation.
 #[repr(C)]
 #[derive(Copy, Clone, Debug, PartialEq)]
+#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
 pub struct Transform {
     /// The basis is a matrix containing 3 Vector3 as its columns: X axis, Y axis, and Z axis.
     /// These vectors can be interpreted as the basis vectors of local coordinate system

gdnative-core/src/core_types/mod.rs

@@ -43,7 +43,7 @@ pub use rid::*;
 pub use string::*;
 pub use string_array::*;
 pub use transform2d::*;
-pub use typed_array::TypedArray;
+pub use typed_array::{Element, TypedArray};
 pub use variant::*;
 pub use variant_array::*;
 pub use vector2::*;

gdnative-core/src/core_types/node_path.rs

@@ -176,3 +176,60 @@ impl fmt::Debug for NodePath {
         write!(f, "NodePath({})", self.to_string())
     }
 }
+
+#[cfg(feature = "serde")]
+mod serialize {
+    use super::*;
+    use serde::{
+        de::{Error, Visitor},
+        Deserialize, Deserializer, Serialize, Serializer,
+    };
+    use std::fmt::Formatter;
+
+    impl Serialize for NodePath {
+        #[inline]
+        fn serialize<S>(&self, ser: S) -> Result<<S as Serializer>::Ok, <S as Serializer>::Error>
+        where
+            S: Serializer,
+        {
+            ser.serialize_newtype_struct("NodePath", &*self.to_string())
+        }
+    }
+
+    impl<'de> Deserialize<'de> for NodePath {
+        #[inline]
+        fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+        where
+            D: Deserializer<'de>,
+        {
+            struct NodePathVisitor;
+
+            impl<'de> Visitor<'de> for NodePathVisitor {
+                type Value = NodePath;
+
+                fn expecting(&self, formatter: &mut Formatter) -> fmt::Result {
+                    formatter.write_str("a NodePath")
+                }
+
+                fn visit_str<E>(self, s: &str) -> Result<Self::Value, E>
+                where
+                    E: Error,
+                {
+                    Ok(NodePath::from_str(s))
+                }
+
+                fn visit_newtype_struct<D>(
+                    self,
+                    deserializer: D,
+                ) -> Result<Self::Value, <D as Deserializer<'de>>::Error>
+                where
+                    D: Deserializer<'de>,
+                {
+                    deserializer.deserialize_str(self)
+                }
+            }
+
+            deserializer.deserialize_newtype_struct("NodePath", NodePathVisitor)
+        }
+    }
+}

gdnative-core/src/core_types/quat.rs

@@ -3,6 +3,7 @@ use glam::EulerRot;
 use std::ops::{Mul, Neg};
 
 #[derive(Copy, Clone, Debug, PartialEq)]
+#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
 #[repr(C)]
 pub struct Quat {
     pub x: f32,