src: add abstract `IsolatePlatformDelegate`

Adds a new abstract class for module authors and embedders to register
arbitrary isolates with `node::MultiIsolatePlatform`.

PR-URL: https://github.com/nodejs/node/pull/30324
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: Joyee Cheung <joyeec9h3@gmail.com>

3 files changed, 65 insertions, 8 deletions

diff --git a/test/cctest/node_test_fixture.cc b/test/cctest/node_test_fixture.cc
index 1a50e58dd9..b6f4af6b9e 100644
--- a/test/cctest/node_test_fixture.cc
+++ b/test/cctest/node_test_fixture.cc
@@ -1,7 +1,7 @@
 #include "node_test_fixture.h"
 
-ArrayBufferUniquePtr NodeTestFixture::allocator{nullptr, nullptr};
-uv_loop_t NodeTestFixture::current_loop;
-NodePlatformUniquePtr NodeTestFixture::platform;
-TracingAgentUniquePtr NodeTestFixture::tracing_agent;
-bool NodeTestFixture::node_initialized = false;
+ArrayBufferUniquePtr NodeZeroIsolateTestFixture::allocator{nullptr, nullptr};
+uv_loop_t NodeZeroIsolateTestFixture::current_loop;
+NodePlatformUniquePtr NodeZeroIsolateTestFixture::platform;
+TracingAgentUniquePtr NodeZeroIsolateTestFixture::tracing_agent;
+bool NodeZeroIsolateTestFixture::node_initialized = false;
diff --git a/test/cctest/node_test_fixture.h b/test/cctest/node_test_fixture.h
index ac0701d094..c8cb923297 100644
--- a/test/cctest/node_test_fixture.h
+++ b/test/cctest/node_test_fixture.h
@@ -60,14 +60,13 @@ using ArrayBufferUniquePtr = std::unique_ptr<node::ArrayBufferAllocator,
 using TracingAgentUniquePtr = std::unique_ptr<node::tracing::Agent>;
 using NodePlatformUniquePtr = std::unique_ptr<node::NodePlatform>;
 
-class NodeTestFixture : public ::testing::Test {
+class NodeZeroIsolateTestFixture : public ::testing::Test {
  protected:
   static ArrayBufferUniquePtr allocator;
   static TracingAgentUniquePtr tracing_agent;
   static NodePlatformUniquePtr platform;
   static uv_loop_t current_loop;
   static bool node_initialized;
-  v8::Isolate* isolate_;
 
   static void SetUpTestCase() {
     if (!node_initialized) {
@@ -99,8 +98,18 @@ class NodeTestFixture : public ::testing::Test {
   void SetUp() override {
     allocator = ArrayBufferUniquePtr(node::CreateArrayBufferAllocator(),
                                      &node::FreeArrayBufferAllocator);
+  }
+};
+
+
+class NodeTestFixture : public NodeZeroIsolateTestFixture {
+ protected:
+  v8::Isolate* isolate_;
+
+  void SetUp() override {
+    NodeZeroIsolateTestFixture::SetUp();
     isolate_ = NewIsolate(allocator.get(), &current_loop);
-    CHECK_NE(isolate_, nullptr);
+    CHECK_NOT_NULL(isolate_);
     isolate_->Enter();
   }
 
@@ -110,6 +119,7 @@ class NodeTestFixture : public ::testing::Test {
     isolate_->Dispose();
     platform->UnregisterIsolate(isolate_);
     isolate_ = nullptr;
+    NodeZeroIsolateTestFixture::TearDown();
   }
 };
 
diff --git a/test/cctest/test_platform.cc b/test/cctest/test_platform.cc
index 5420502124..73057bb2d8 100644
--- a/test/cctest/test_platform.cc
+++ b/test/cctest/test_platform.cc
@@ -57,3 +57,50 @@ TEST_F(PlatformTest, SkipNewTasksInFlushForegroundTasks) {
   EXPECT_EQ(3, run_count);
   EXPECT_FALSE(platform->FlushForegroundTasks(isolate_));
 }
+
+// Tests the registration of an abstract `IsolatePlatformDelegate` instance as
+// opposed to the more common `uv_loop_s*` version of `RegisterIsolate`.
+TEST_F(NodeZeroIsolateTestFixture, IsolatePlatformDelegateTest) {
+  // Allocate isolate
+  v8::Isolate::CreateParams create_params;
+  create_params.array_buffer_allocator = allocator.get();
+  auto isolate = v8::Isolate::Allocate();
+  CHECK_NOT_NULL(isolate);
+
+  // Register *first*, then initialize
+  auto delegate = std::make_shared<node::PerIsolatePlatformData>(
+    isolate,
+    &current_loop);
+  platform->RegisterIsolate(isolate, delegate.get());
+  v8::Isolate::Initialize(isolate, create_params);
+
+  // Try creating Context + IsolateData + Environment
+  {
+    v8::Isolate::Scope isolate_scope(isolate);
+    v8::HandleScope handle_scope(isolate);
+
+    auto context = node::NewContext(isolate);
+    CHECK(!context.IsEmpty());
+    v8::Context::Scope context_scope(context);
+
+    std::unique_ptr<node::IsolateData, decltype(&node::FreeIsolateData)>
+      isolate_data{node::CreateIsolateData(isolate,
+                                           &current_loop,
+                                           platform.get()),
+                   node::FreeIsolateData};
+    CHECK(isolate_data);
+
+    std::unique_ptr<node::Environment, decltype(&node::FreeEnvironment)>
+      environment{node::CreateEnvironment(isolate_data.get(),
+                                          context,
+                                          0, nullptr,
+                                          0, nullptr),
+                  node::FreeEnvironment};
+    CHECK(environment);
+  }
+
+  // Graceful shutdown
+  delegate->Shutdown();
+  isolate->Dispose();
+  platform->UnregisterIsolate(isolate);
+}