1 files changed, 554 insertions, 0 deletions
diff --git a/serde_v8/ser.rs b/serde_v8/ser.rs
new file mode 100644
index 000000000..5241aeaef
--- /dev/null
+++ b/serde_v8/ser.rs
@@ -0,0 +1,554 @@
+// Copyright 2018-2022 the Deno authors. All rights reserved. MIT license.
+use serde::ser;
+use serde::ser::Serialize;
+
+use std::cell::RefCell;
+
+use crate::error::{Error, Result};
+use crate::keys::v8_struct_key;
+use crate::magic::transl8::MAGIC_FIELD;
+use crate::magic::transl8::{opaque_deref, opaque_recv, MagicType, ToV8};
+use crate::{magic, Buffer, ByteString, U16String};
+
+type JsValue<'s> = v8::Local<'s, v8::Value>;
+type JsResult<'s> = Result<JsValue<'s>>;
+
+type ScopePtr<'a, 'b, 'c> = &'c RefCell<&'b mut v8::HandleScope<'a>>;
+
+pub fn to_v8<'a, T>(scope: &mut v8::HandleScope<'a>, input: T) -> JsResult<'a>
+where
+  T: Serialize,
+{
+  let scopeptr = RefCell::new(scope);
+  let serializer = Serializer::new(&scopeptr);
+
+  input.serialize(serializer)
+}
+
+/// Wraps other serializers into an enum tagged variant form.
+/// Uses {"Variant": ...payload...} for compatibility with serde-json.
+pub struct VariantSerializer<'a, 'b, 'c, S> {
+  inner: S,
+  scope: ScopePtr<'a, 'b, 'c>,
+  variant: &'static str,
+}
+
+impl<'a, 'b, 'c, S> VariantSerializer<'a, 'b, 'c, S> {
+  pub fn new(
+    scope: ScopePtr<'a, 'b, 'c>,
+    variant: &'static str,
+    inner: S,
+  ) -> Self {
+    Self {
+      inner,
+      scope,
+      variant,
+    }
+  }
+
+  fn end(self, inner: impl FnOnce(S) -> JsResult<'a>) -> JsResult<'a> {
+    let value = inner(self.inner)?;
+    let scope = &mut *self.scope.borrow_mut();
+    let null = v8::null(scope).into();
+    let key = v8_struct_key(scope, self.variant).into();
+    let obj =
+      v8::Object::with_prototype_and_properties(scope, null, &[key], &[value]);
+    Ok(obj.into())
+  }
+}
+
+impl<'a, 'b, 'c, S> ser::SerializeTupleVariant
+  for VariantSerializer<'a, 'b, 'c, S>
+where
+  S: ser::SerializeTupleStruct<Ok = JsValue<'a>, Error = Error>,
+{
+  type Ok = JsValue<'a>;
+  type Error = Error;
+
+  fn serialize_field<T: ?Sized + Serialize>(
+    &mut self,
+    value: &T,
+  ) -> Result<()> {
+    self.inner.serialize_field(value)
+  }
+
+  fn end(self) -> JsResult<'a> {
+    self.end(S::end)
+  }
+}
+
+impl<'a, 'b, 'c, S> ser::SerializeStructVariant
+  for VariantSerializer<'a, 'b, 'c, S>
+where
+  S: ser::SerializeStruct<Ok = JsValue<'a>, Error = Error>,
+{
+  type Ok = JsValue<'a>;
+  type Error = Error;
+
+  fn serialize_field<T: ?Sized + Serialize>(
+    &mut self,
+    key: &'static str,
+    value: &T,
+  ) -> Result<()> {
+    self.inner.serialize_field(key, value)
+  }
+
+  fn end(self) -> JsResult<'a> {
+    self.end(S::end)
+  }
+}
+
+pub struct ArraySerializer<'a, 'b, 'c> {
+  pending: Vec<JsValue<'a>>,
+  scope: ScopePtr<'a, 'b, 'c>,
+}
+
+impl<'a, 'b, 'c> ArraySerializer<'a, 'b, 'c> {
+  pub fn new(scope: ScopePtr<'a, 'b, 'c>, len: Option<usize>) -> Self {
+    let pending = match len {
+      Some(len) => Vec::with_capacity(len),
+      None => vec![],
+    };
+    Self { pending, scope }
+  }
+}
+
+impl<'a, 'b, 'c> ser::SerializeSeq for ArraySerializer<'a, 'b, 'c> {
+  type Ok = JsValue<'a>;
+  type Error = Error;
+
+  fn serialize_element<T: ?Sized + Serialize>(
+    &mut self,
+    value: &T,
+  ) -> Result<()> {
+    let x = value.serialize(Serializer::new(self.scope))?;
+    self.pending.push(x);
+    Ok(())
+  }
+
+  fn end(self) -> JsResult<'a> {
+    let elements = self.pending.iter().as_slice();
+    let scope = &mut *self.scope.borrow_mut();
+    let arr = v8::Array::new_with_elements(scope, elements);
+    Ok(arr.into())
+  }
+}
+
+impl<'a, 'b, 'c> ser::SerializeTuple for ArraySerializer<'a, 'b, 'c> {
+  type Ok = JsValue<'a>;
+  type Error = Error;
+
+  fn serialize_element<T: ?Sized + Serialize>(
+    &mut self,
+    value: &T,
+  ) -> Result<()> {
+    ser::SerializeSeq::serialize_element(self, value)
+  }
+
+  fn end(self) -> JsResult<'a> {
+    ser::SerializeSeq::end(self)
+  }
+}
+
+impl<'a, 'b, 'c> ser::SerializeTupleStruct for ArraySerializer<'a, 'b, 'c> {
+  type Ok = JsValue<'a>;
+  type Error = Error;
+
+  fn serialize_field<T: ?Sized + Serialize>(
+    &mut self,
+    value: &T,
+  ) -> Result<()> {
+    ser::SerializeTuple::serialize_element(self, value)
+  }
+
+  fn end(self) -> JsResult<'a> {
+    ser::SerializeTuple::end(self)
+  }
+}
+
+pub struct ObjectSerializer<'a, 'b, 'c> {
+  scope: ScopePtr<'a, 'b, 'c>,
+  keys: Vec<v8::Local<'a, v8::Name>>,
+  values: Vec<JsValue<'a>>,
+}
+
+impl<'a, 'b, 'c> ObjectSerializer<'a, 'b, 'c> {
+  pub fn new(scope: ScopePtr<'a, 'b, 'c>, len: usize) -> Self {
+    let keys = Vec::with_capacity(len);
+    let values = Vec::with_capacity(len);
+    Self {
+      scope,
+      keys,
+      values,
+    }
+  }
+}
+
+impl<'a, 'b, 'c> ser::SerializeStruct for ObjectSerializer<'a, 'b, 'c> {
+  type Ok = JsValue<'a>;
+  type Error = Error;
+
+  fn serialize_field<T: ?Sized + Serialize>(
+    &mut self,
+    key: &'static str,
+    value: &T,
+  ) -> Result<()> {
+    let value = value.serialize(Serializer::new(self.scope))?;
+    let scope = &mut *self.scope.borrow_mut();
+    let key = v8_struct_key(scope, key).into();
+    self.keys.push(key);
+    self.values.push(value);
+    Ok(())
+  }
+
+  fn end(self) -> JsResult<'a> {
+    let scope = &mut *self.scope.borrow_mut();
+    let null = v8::null(scope);
+    let obj = v8::Object::with_prototype_and_properties(
+      scope,
+      null.into(),
+      &self.keys[..],
+      &self.values[..],
+    );
+    Ok(obj.into())
+  }
+}
+
+pub struct MagicalSerializer<'a, 'b, 'c, T> {
+  scope: ScopePtr<'a, 'b, 'c>,
+  opaque: u64,
+  p1: std::marker::PhantomData<T>,
+}
+
+impl<'a, 'b, 'c, T> MagicalSerializer<'a, 'b, 'c, T> {
+  pub fn new(scope: ScopePtr<'a, 'b, 'c>) -> MagicalSerializer<'a, 'b, 'c, T> {
+    Self {
+      scope,
+      opaque: 0,
+      p1: std::marker::PhantomData::<T> {},
+    }
+  }
+}
+
+impl<'a, 'b, 'c, T: MagicType + ToV8> ser::SerializeStruct
+  for MagicalSerializer<'a, 'b, 'c, T>
+{
+  type Ok = JsValue<'a>;
+  type Error = Error;
+
+  fn serialize_field<U: ?Sized + Serialize>(
+    &mut self,
+    key: &'static str,
+    value: &U,
+  ) -> Result<()> {
+    assert_eq!(key, MAGIC_FIELD);
+    let ptr: &U = value;
+    // SAFETY: MagicalSerializer only ever receives single field u64s,
+    // type-safety is ensured by MAGIC_NAME checks in `serialize_struct()`
+    self.opaque = unsafe { opaque_recv(ptr) };
+    Ok(())
+  }
+
+  fn end(self) -> JsResult<'a> {
+    // SAFETY: transerialization assumptions imply `T` is still alive.
+    let x: &T = unsafe { opaque_deref(self.opaque) };
+    let scope = &mut *self.scope.borrow_mut();
+    x.to_v8(scope)
+  }
+}
+
+// Dispatches between magic and regular struct serializers
+pub enum StructSerializers<'a, 'b, 'c> {
+  Magic(MagicalSerializer<'a, 'b, 'c, magic::Value<'a>>),
+  MagicBuffer(MagicalSerializer<'a, 'b, 'c, Buffer>),
+  MagicByteString(MagicalSerializer<'a, 'b, 'c, ByteString>),
+  MagicU16String(MagicalSerializer<'a, 'b, 'c, U16String>),
+  Regular(ObjectSerializer<'a, 'b, 'c>),
+}
+
+impl<'a, 'b, 'c> ser::SerializeStruct for StructSerializers<'a, 'b, 'c> {
+  type Ok = JsValue<'a>;
+  type Error = Error;
+
+  fn serialize_field<T: ?Sized + Serialize>(
+    &mut self,
+    key: &'static str,
+    value: &T,
+  ) -> Result<()> {
+    match self {
+      StructSerializers::Magic(s) => s.serialize_field(key, value),
+      StructSerializers::MagicBuffer(s) => s.serialize_field(key, value),
+      StructSerializers::MagicByteString(s) => s.serialize_field(key, value),
+      StructSerializers::MagicU16String(s) => s.serialize_field(key, value),
+      StructSerializers::Regular(s) => s.serialize_field(key, value),
+    }
+  }
+
+  fn end(self) -> JsResult<'a> {
+    match self {
+      StructSerializers::Magic(s) => s.end(),
+      StructSerializers::MagicBuffer(s) => s.end(),
+      StructSerializers::MagicByteString(s) => s.end(),
+      StructSerializers::MagicU16String(s) => s.end(),
+      StructSerializers::Regular(s) => s.end(),
+    }
+  }
+}
+
+// Serializes to JS Objects, NOT JS Maps ...
+pub struct MapSerializer<'a, 'b, 'c> {
+  scope: ScopePtr<'a, 'b, 'c>,
+  keys: Vec<v8::Local<'a, v8::Name>>,
+  values: Vec<JsValue<'a>>,
+}
+
+impl<'a, 'b, 'c> MapSerializer<'a, 'b, 'c> {
+  pub fn new(scope: ScopePtr<'a, 'b, 'c>, len: Option<usize>) -> Self {
+    let keys = Vec::with_capacity(len.unwrap_or_default());
+    let values = Vec::with_capacity(len.unwrap_or_default());
+    Self {
+      scope,
+      keys,
+      values,
+    }
+  }
+}
+
+impl<'a, 'b, 'c> ser::SerializeMap for MapSerializer<'a, 'b, 'c> {
+  type Ok = JsValue<'a>;
+  type Error = Error;
+
+  fn serialize_key<T: ?Sized + Serialize>(&mut self, key: &T) -> Result<()> {
+    let key = key.serialize(Serializer::new(self.scope))?;
+    self.keys.push(key.try_into().map_err(|_| {
+      Error::Message("Serialized Maps expect String keys".into())
+    })?);
+    Ok(())
+  }
+
+  fn serialize_value<T: ?Sized + Serialize>(
+    &mut self,
+    value: &T,
+  ) -> Result<()> {
+    let v8_value = value.serialize(Serializer::new(self.scope))?;
+    self.values.push(v8_value);
+    Ok(())
+  }
+
+  fn end(self) -> JsResult<'a> {
+    debug_assert!(self.keys.len() == self.values.len());
+    let scope = &mut *self.scope.borrow_mut();
+    let null = v8::null(scope).into();
+    let obj = v8::Object::with_prototype_and_properties(
+      scope,
+      null,
+      &self.keys[..],
+      &self.values[..],
+    );
+    Ok(obj.into())
+  }
+}
+
+pub struct Serializer<'a, 'b, 'c> {
+  scope: ScopePtr<'a, 'b, 'c>,
+}
+
+impl<'a, 'b, 'c> Serializer<'a, 'b, 'c> {
+  pub fn new(scope: ScopePtr<'a, 'b, 'c>) -> Self {
+    Serializer { scope }
+  }
+}
+
+macro_rules! forward_to {
+    ($($name:ident($ty:ty, $to:ident, $lt:lifetime);)*) => {
+        $(fn $name(self, v: $ty) -> JsResult<$lt> {
+            self.$to(v as _)
+        })*
+    };
+}
+
+impl<'a, 'b, 'c> ser::Serializer for Serializer<'a, 'b, 'c> {
+  type Ok = v8::Local<'a, v8::Value>;
+  type Error = Error;
+
+  type SerializeSeq = ArraySerializer<'a, 'b, 'c>;
+  type SerializeTuple = ArraySerializer<'a, 'b, 'c>;
+  type SerializeTupleStruct = ArraySerializer<'a, 'b, 'c>;
+  type SerializeTupleVariant =
+    VariantSerializer<'a, 'b, 'c, ArraySerializer<'a, 'b, 'c>>;
+  type SerializeMap = MapSerializer<'a, 'b, 'c>;
+  type SerializeStruct = StructSerializers<'a, 'b, 'c>;
+  type SerializeStructVariant =
+    VariantSerializer<'a, 'b, 'c, StructSerializers<'a, 'b, 'c>>;
+
+  forward_to! {
+      serialize_i8(i8, serialize_i32, 'a);
+      serialize_i16(i16, serialize_i32, 'a);
+
+      serialize_u8(u8, serialize_u32, 'a);
+      serialize_u16(u16, serialize_u32, 'a);
+
+      serialize_f32(f32, serialize_f64, 'a);
+      serialize_u64(u64, serialize_f64, 'a);
+      serialize_i64(i64, serialize_f64, 'a);
+  }
+
+  fn serialize_i32(self, v: i32) -> JsResult<'a> {
+    Ok(v8::Integer::new(&mut self.scope.borrow_mut(), v).into())
+  }
+
+  fn serialize_u32(self, v: u32) -> JsResult<'a> {
+    Ok(v8::Integer::new_from_unsigned(&mut self.scope.borrow_mut(), v).into())
+  }
+
+  fn serialize_f64(self, v: f64) -> JsResult<'a> {
+    Ok(v8::Number::new(&mut self.scope.borrow_mut(), v).into())
+  }
+
+  fn serialize_bool(self, v: bool) -> JsResult<'a> {
+    Ok(v8::Boolean::new(&mut self.scope.borrow_mut(), v).into())
+  }
+
+  fn serialize_char(self, _v: char) -> JsResult<'a> {
+    unimplemented!();
+  }
+
+  fn serialize_str(self, v: &str) -> JsResult<'a> {
+    v8::String::new(&mut self.scope.borrow_mut(), v)
+      .map(|v| v.into())
+      .ok_or(Error::ExpectedString)
+  }
+
+  fn serialize_bytes(self, _v: &[u8]) -> JsResult<'a> {
+    // TODO: investigate using Uint8Arrays
+    unimplemented!()
+  }
+
+  fn serialize_none(self) -> JsResult<'a> {
+    Ok(v8::null(&mut self.scope.borrow_mut()).into())
+  }
+
+  fn serialize_some<T: ?Sized + Serialize>(self, value: &T) -> JsResult<'a> {
+    value.serialize(self)
+  }
+
+  fn serialize_unit(self) -> JsResult<'a> {
+    Ok(v8::null(&mut self.scope.borrow_mut()).into())
+  }
+
+  fn serialize_unit_struct(self, _name: &'static str) -> JsResult<'a> {
+    Ok(v8::null(&mut self.scope.borrow_mut()).into())
+  }
+
+  /// For compatibility with serde-json, serialises unit variants as "Variant" strings.
+  fn serialize_unit_variant(
+    self,
+    _name: &'static str,
+    _variant_index: u32,
+    variant: &'static str,
+  ) -> JsResult<'a> {
+    Ok(v8_struct_key(&mut self.scope.borrow_mut(), variant).into())
+  }
+
+  fn serialize_newtype_struct<T: ?Sized + Serialize>(
+    self,
+    _name: &'static str,
+    value: &T,
+  ) -> JsResult<'a> {
+    value.serialize(self)
+  }
+
+  fn serialize_newtype_variant<T: ?Sized + Serialize>(
+    self,
+    _name: &'static str,
+    _variant_index: u32,
+    variant: &'static str,
+    value: &T,
+  ) -> JsResult<'a> {
+    let scope = self.scope;
+    let x = self.serialize_newtype_struct(variant, value)?;
+    VariantSerializer::new(scope, variant, x).end(Ok)
+  }
+
+  /// Serialises any Rust iterable into a JS Array
+  fn serialize_seq(self, len: Option<usize>) -> Result<Self::SerializeSeq> {
+    Ok(ArraySerializer::new(self.scope, len))
+  }
+
+  fn serialize_tuple(self, len: usize) -> Result<Self::SerializeTuple> {
+    self.serialize_seq(Some(len))
+  }
+
+  fn serialize_tuple_struct(
+    self,
+    _name: &'static str,
+    len: usize,
+  ) -> Result<Self::SerializeTupleStruct> {
+    self.serialize_tuple(len)
+  }
+
+  fn serialize_tuple_variant(
+    self,
+    _name: &'static str,
+    _variant_index: u32,
+    variant: &'static str,
+    len: usize,
+  ) -> Result<Self::SerializeTupleVariant> {
+    Ok(VariantSerializer::new(
+      self.scope,
+      variant,
+      self.serialize_tuple_struct(variant, len)?,
+    ))
+  }
+
+  fn serialize_map(self, len: Option<usize>) -> Result<Self::SerializeMap> {
+    // Serializes a rust Map (e.g: BTreeMap, HashMap) to a v8 Object
+    // TODO: consider allowing serializing to v8 Maps (e.g: via a magic type)
+    // since they're lighter and better suited for K/V data
+    // and maybe restrict keys (e.g: strings and numbers)
+    Ok(MapSerializer::new(self.scope, len))
+  }
+
+  /// Serialises Rust typed structs into plain JS objects.
+  fn serialize_struct(
+    self,
+    name: &'static str,
+    len: usize,
+  ) -> Result<Self::SerializeStruct> {
+    match name {
+      ByteString::MAGIC_NAME => {
+        let m = MagicalSerializer::<ByteString>::new(self.scope);
+        Ok(StructSerializers::MagicByteString(m))
+      }
+      U16String::MAGIC_NAME => {
+        let m = MagicalSerializer::<U16String>::new(self.scope);
+        Ok(StructSerializers::MagicU16String(m))
+      }
+      Buffer::MAGIC_NAME => {
+        let m = MagicalSerializer::<Buffer>::new(self.scope);
+        Ok(StructSerializers::MagicBuffer(m))
+      }
+      magic::Value::MAGIC_NAME => {
+        let m = MagicalSerializer::<magic::Value<'a>>::new(self.scope);
+        Ok(StructSerializers::Magic(m))
+      }
+      _ => {
+        // Regular structs
+        let o = ObjectSerializer::new(self.scope, len);
+        Ok(StructSerializers::Regular(o))
+      }
+    }
+  }
+
+  fn serialize_struct_variant(
+    self,
+    _name: &'static str,
+    _variant_index: u32,
+    variant: &'static str,
+    len: usize,
+  ) -> Result<Self::SerializeStructVariant> {
+    let scope = self.scope;
+    let x = self.serialize_struct(variant, len)?;
+    Ok(VariantSerializer::new(scope, variant, x))
+  }
+}