inspector: support extra contexts

This enables inspector support for contexts created using the vm module.

PR-URL: #14465
Reviewed-By: Jan Krems <jan.krems@gmail.com>
Reviewed-By: Timothy Gu <timothygu99@gmail.com>
Reviewed-By: Aleksey Kozyatinskiy <kozyatinskiy@chromium.org>

Author: Eugene Ostroukhov

src/env-inl.h

@@ -259,6 +259,9 @@ inline void Environment::TickInfo::set_index(uint32_t value) {
 
 inline void Environment::AssignToContext(v8::Local<v8::Context> context) {
   context->SetAlignedPointerInEmbedderData(kContextEmbedderDataIndex, this);
+#if HAVE_INSPECTOR
+  inspector_agent()->ContextCreated(context);
+#endif  // HAVE_INSPECTOR
 }
 
 inline Environment* Environment::GetCurrent(v8::Isolate* isolate) {

src/inspector_agent.cc

@@ -12,6 +12,7 @@
 #include "libplatform/libplatform.h"
 
 #include <string.h>
+#include <sstream>
 #include <unordered_map>
 #include <vector>
 
@@ -500,6 +501,7 @@ class NodeInspectorClient : public V8InspectorClient {
                                                 terminated_(false),
                                                 running_nested_loop_(false) {
     client_ = V8Inspector::create(env->isolate(), this);
+    contextCreated(env->context(), "Node.js Main Context");
   }
 
   void runMessageLoopOnPause(int context_group_id) override {
@@ -627,7 +629,8 @@ class NodeInspectorClient : public V8InspectorClient {
 Agent::Agent(Environment* env) : parent_env_(env),
                                  client_(nullptr),
                                  platform_(nullptr),
-                                 enabled_(false) {}
+                                 enabled_(false),
+                                 next_context_number_(1) {}
 
 // Destructor needs to be defined here in implementation file as the header
 // does not have full definition of some classes.
@@ -641,7 +644,6 @@ bool Agent::Start(v8::Platform* platform, const char* path,
   client_ =
       std::unique_ptr<NodeInspectorClient>(
           new NodeInspectorClient(parent_env_, platform));
-  client_->contextCreated(parent_env_->context(), "Node.js Main Context");
   platform_ = platform;
   CHECK_EQ(0, uv_async_init(uv_default_loop(),
                             &start_io_thread_async,
@@ -841,6 +843,14 @@ void Agent::RequestIoThreadStart() {
   uv_async_send(&start_io_thread_async);
 }
 
+void Agent::ContextCreated(Local<Context> context) {
+  if (client_ == nullptr)  // This happens for a main context
+    return;
+  std::ostringstream name;
+  name << "VM Context " << next_context_number_++;
+  client_->contextCreated(context, name.str());
+}
+
 }  // namespace inspector
 }  // namespace node
 

src/inspector_agent.h

@@ -96,6 +96,7 @@ class Agent {
   void RequestIoThreadStart();
 
   DebugOptions& options() { return debug_options_; }
+  void ContextCreated(v8::Local<v8::Context> context);
 
  private:
   node::Environment* parent_env_;
@@ -105,6 +106,7 @@ class Agent {
   bool enabled_;
   std::string path_;
   DebugOptions debug_options_;
+  int next_context_number_;
 };
 
 }  // namespace inspector

test/inspector/test-contexts.js

@@ -0,0 +1,63 @@
+'use strict';
+
+// Flags: --expose-gc
+
+const common = require('../common');
+common.skipIfInspectorDisabled();
+
+const { strictEqual } = require('assert');
+const { runInNewContext } = require('vm');
+const { Session } = require('inspector');
+
+const session = new Session();
+session.connect();
+
+function notificationPromise(method) {
+  return new Promise((resolve) => session.once(method, resolve));
+}
+
+async function testContextCreatedAndDestroyed() {
+  console.log('Testing context created/destroyed notifications');
+  const mainContextPromise =
+      notificationPromise('Runtime.executionContextCreated');
+
+  session.post('Runtime.enable');
+  let contextCreated = await mainContextPromise;
+  strictEqual('Node.js Main Context',
+              contextCreated.params.context.name,
+              JSON.stringify(contextCreated));
+
+  const secondContextCreatedPromise =
+      notificationPromise('Runtime.executionContextCreated');
+
+  let contextDestroyed = null;
+  session.once('Runtime.executionContextDestroyed',
+               (notification) => contextDestroyed = notification);
+
+  runInNewContext('1 + 1', {});
+
+  contextCreated = await secondContextCreatedPromise;
+  strictEqual('VM Context 1',
+              contextCreated.params.context.name,
+              JSON.stringify(contextCreated));
+
+  // GC is unpredictable...
+  while (!contextDestroyed)
+    global.gc();
+
+  strictEqual(contextCreated.params.context.id,
+              contextDestroyed.params.executionContextId,
+              JSON.stringify(contextDestroyed));
+}
+
+async function testBreakpointHit() {
+  console.log('Testing breakpoint is hit in a new context');
+  session.post('Debugger.enable');
+
+  const pausedPromise = notificationPromise('Debugger.paused');
+  runInNewContext('debugger', {});
+  await pausedPromise;
+}
+
+common.crashOnUnhandledRejection();
+testContextCreatedAndDestroyed().then(testBreakpointHit);