From 42af31ff382aee1c8c371d7c35ffd6cba596b454 Mon Sep 17 00:00:00 2001
From: Ben Noordhuis <info@bnoordhuis.nl>
Date: Sun, 19 Jan 2020 00:38:41 +0100
Subject: [PATCH] Add Context::new_from_template() (#225)

---
 src/binding.cc    |  9 ++++-----
 src/context.rs    | 22 ++++++++++++++++++++--
 tests/test_api.rs | 23 +++++++++++++++++++++++
 3 files changed, 47 insertions(+), 7 deletions(-)

diff --git a/src/binding.cc b/src/binding.cc
index 7c0b1e3e..50f69cdf 100644
--- a/src/binding.cc
+++ b/src/binding.cc
@@ -767,11 +767,10 @@ void DeserializeInternalFields(v8::Local<v8::Object> holder, int index,
   deserialized_data.push_back(embedder_field);
 }
 
-v8::Context* v8__Context__New(v8::Isolate* isolate) {
-  // TODO: optional arguments.
-  return *v8::Context::New(isolate, nullptr,
-                           v8::MaybeLocal<v8::ObjectTemplate>(),
-                           v8::MaybeLocal<v8::Value>(),
+v8::Context* v8__Context__New(v8::Isolate* isolate,
+                              v8::MaybeLocal<v8::ObjectTemplate> templ,
+                              v8::MaybeLocal<v8::Value> global_object) {
+  return *v8::Context::New(isolate, nullptr, templ, global_object,
                            v8::DeserializeInternalFieldsCallback(
                                DeserializeInternalFields, nullptr));
 }
diff --git a/src/context.rs b/src/context.rs
index 8ba5a47b..2aea63e9 100644
--- a/src/context.rs
+++ b/src/context.rs
@@ -3,10 +3,17 @@ use crate::isolate::Isolate;
 use crate::support::Opaque;
 use crate::Local;
 use crate::Object;
+use crate::ObjectTemplate;
 use crate::ToLocal;
+use crate::Value;
+use std::ptr::null;
 
 extern "C" {
-  fn v8__Context__New(isolate: &Isolate) -> *mut Context;
+  fn v8__Context__New(
+    isolate: &Isolate,
+    templ: *const ObjectTemplate,
+    data: *const Value,
+  ) -> *mut Context;
   fn v8__Context__Enter(this: &mut Context);
   fn v8__Context__Exit(this: &mut Context);
   fn v8__Context__Global(this: *mut Context) -> *mut Object;
@@ -18,9 +25,20 @@ extern "C" {
 pub struct Context(Opaque);
 
 impl Context {
+  /// Creates a new context.
   pub fn new<'sc>(scope: &mut impl ToLocal<'sc>) -> Local<'sc, Context> {
     // TODO: optional arguments;
-    let ptr = unsafe { v8__Context__New(scope.isolate()) };
+    let ptr = unsafe { v8__Context__New(scope.isolate(), null(), null()) };
+    unsafe { scope.to_local(ptr) }.unwrap()
+  }
+
+  /// Creates a new context using the object template as the template for
+  /// the global object.
+  pub fn new_from_template<'sc>(
+    scope: &mut impl ToLocal<'sc>,
+    templ: Local<ObjectTemplate>,
+  ) -> Local<'sc, Context> {
+    let ptr = unsafe { v8__Context__New(scope.isolate(), &*templ, null()) };
     unsafe { scope.to_local(ptr) }.unwrap()
   }
 
diff --git a/tests/test_api.rs b/tests/test_api.rs
index 7cb4f422..7870b14f 100644
--- a/tests/test_api.rs
+++ b/tests/test_api.rs
@@ -2247,3 +2247,26 @@ fn inspector_dispatch_protocol_message() {
   assert_eq!(channel.send_notification_count, 0);
   assert_eq!(channel.flush_protocol_notifications_count, 0);
 }
+
+#[test]
+fn context_from_object_template() {
+  let _setup_guard = setup();
+  let mut params = v8::Isolate::create_params();
+  params.set_array_buffer_allocator(v8::new_default_allocator());
+  let isolate = v8::Isolate::new(params);
+  let mut locker = v8::Locker::new(&isolate);
+  {
+    let mut hs = v8::HandleScope::new(&mut locker);
+    let scope = hs.enter();
+    let object_templ = v8::ObjectTemplate::new(scope);
+    let function_templ = v8::FunctionTemplate::new(scope, fortytwo_callback);
+    let name = v8_str(scope, "f");
+    object_templ.set(name.into(), function_templ.into());
+    let context = v8::Context::new_from_template(scope, object_templ);
+    let mut cs = v8::ContextScope::new(scope, context);
+    let scope = cs.enter();
+    let actual = eval(scope, context, "f()").unwrap();
+    let expected = v8::Integer::new(scope, 42);
+    assert!(expected.strict_equals(actual));
+  }
+}