add v8::JSON (#54)

BUILD.gn

@@ -12,6 +12,7 @@ v8_static_library("rusty_v8") {
     "src/inspector/client.cc",
     "src/inspector/string_buffer.cc",
     "src/isolate.cc",
+    "src/json.cc",
     "src/locker.cc",
     "src/number.cc",
     "src/platform/mod.cc",

src/json.cc

@@ -0,0 +1,14 @@
+#include "support.h"
+#include "v8/include/v8.h"
+
+using namespace support;
+
+extern "C" {
+v8::Value *v8__JSON__Parse(v8::Local<v8::Context> context, v8::Local<v8::String> json_string) {
+    return maybe_local_to_ptr(v8::JSON::Parse(context, json_string));
+}
+
+v8::String *v8__JSON__Stringify(v8::Local<v8::Context> context, v8::Local<v8::Value> json_object) {
+    return maybe_local_to_ptr(v8::JSON::Stringify(context, json_object));
+}
+}

src/json.rs

@@ -0,0 +1,44 @@
+#![allow(non_snake_case)]
+
+use crate::Context;
+use crate::Local;
+use crate::String;
+use crate::Value;
+
+extern "C" {
+  fn v8__JSON__Parse(
+    context: *mut Context,
+    json_string: *mut String,
+  ) -> *mut Value;
+  fn v8__JSON__Stringify(
+    context: *mut Context,
+    json_object: *mut Value,
+  ) -> *mut String;
+}
+
+/// A JSON Parser and Stringifier
+pub mod JSON {
+  use super::*;
+
+  /// Tries to parse the string `json_string` and returns it as value if
+  /// successful.
+  pub fn Parse<'sc>(
+    mut context: Local<'sc, Context>,
+    mut json_string: Local<'sc, String>,
+  ) -> Option<Local<'sc, Value>> {
+    unsafe {
+      Local::from_raw(v8__JSON__Parse(&mut *context, &mut *json_string))
+    }
+  }
+
+  /// Tries to stringify the JSON-serializable object `json_object` and returns
+  /// it as string if successful.
+  pub fn Stringify<'sc>(
+    mut context: Local<'sc, Context>,
+    mut json_object: Local<'sc, Value>,
+  ) -> Option<Local<'sc, String>> {
+    unsafe {
+      Local::from_raw(v8__JSON__Stringify(&mut *context, &mut *json_object))
+    }
+  }
+}

src/lib.rs

@@ -15,6 +15,7 @@ mod context;
 mod exception;
 mod handle_scope;
 mod isolate;
+mod json;
 mod local;
 mod locker;
 mod number;
@@ -36,6 +37,7 @@ pub use context::Context;
 pub use exception::Exception;
 pub use handle_scope::HandleScope;
 pub use isolate::Isolate;
+pub use json::JSON;
 pub use local::Local;
 pub use locker::Locker;
 pub use number::{Integer, Number};

tests/test_api.rs

@@ -242,3 +242,30 @@ fn exception() {
   });
   isolate.exit();
 }
+
+#[test]
+fn json() {
+  setup();
+  let mut params = v8::Isolate::create_params();
+  params.set_array_buffer_allocator(
+    v8::array_buffer::Allocator::new_default_allocator(),
+  );
+  let mut isolate = v8::Isolate::new(params);
+  let mut locker = v8::Locker::new(&mut isolate);
+  v8::HandleScope::enter(&mut locker, |s| {
+    let mut context = v8::Context::new(s);
+    context.enter();
+    let json_string =
+        v8::String::new(s, "{\"a\": 1, \"b\": 2}", Default::default())
+            .unwrap();
+    let maybe_value = v8::JSON::Parse(context, json_string);
+    assert!(maybe_value.is_some());
+    let value = maybe_value.unwrap();
+    let maybe_stringified = v8::JSON::Stringify(context, value);
+    assert!(maybe_stringified.is_some());
+    let stringified = maybe_stringified.unwrap();
+    let rust_str = stringified.to_rust_string_lossy(s);
+    assert_eq!("{\"a\":1,\"b\":2}".to_string(), rust_str);
+    context.exit();
+  });
+}