[d8] Don't process message queues in load

After processing the string loaded from a file, don't process message
queues. Otherwise, stack traces generated in any processed task will
contain the stack trace of the load. This also introduces
nondeterminism, since it depends on the timing whether something will
be processed inside the load or outside.

Drive-by: Introduce enums for the different bools, to make their
meaning more obvious at call sites.

R=yangguo@chromium.org
CC=herhut@chromium.org

Change-Id: Ib48ee01be8c443a2a408ecb1c9e34bb9ba5a8fe7
Reviewed-on: https://chromium-review.googlesource.com/964141Reviewed-by: Yang Guo <yangguo@chromium.org>
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51952}

src/d8.cc

@@ -572,8 +572,9 @@ void Shell::StoreInCodeCache(Isolate* isolate, Local<Value> source,
 
 // Executes a string within the current v8 context.
 bool Shell::ExecuteString(Isolate* isolate, Local<String> source,
-                          Local<Value> name, bool print_result,
-                          bool report_exceptions) {
+                          Local<Value> name, PrintResult print_result,
+                          ReportExceptions report_exceptions,
+                          ProcessMessageQueue process_message_queue) {
   HandleScope handle_scope(isolate);
   TryCatch try_catch(isolate);
   try_catch.SetVerbose(true);
@@ -651,7 +652,7 @@ bool Shell::ExecuteString(Isolate* isolate, Local<String> source,
       StoreInCodeCache(isolate, source, cached_data);
       delete cached_data;
     }
-    if (!EmptyMessageQueues(isolate)) success = false;
+    if (process_message_queue && !EmptyMessageQueues(isolate)) success = false;
     data->realm_current_ = data->realm_switch_;
   }
   Local<Value> result;
@@ -1373,11 +1374,14 @@ void Shell::Load(const v8::FunctionCallbackInfo<v8::Value>& args) {
       Throw(args.GetIsolate(), "Error loading file");
       return;
     }
-    if (!ExecuteString(args.GetIsolate(), source,
+    if (!ExecuteString(
+            args.GetIsolate(), source,
             String::NewFromUtf8(args.GetIsolate(), *file,
                                 NewStringType::kNormal)
                 .ToLocalChecked(),
-                       false, !options.quiet_load)) {
+            kNoPrintResult,
+            options.quiet_load ? kNoReportExceptions : kReportExceptions,
+            kNoProcessMessageQueue)) {
       Throw(args.GetIsolate(), "Error executing file");
       return;
     }
@@ -2269,7 +2273,8 @@ void Shell::RunShell(Isolate* isolate) {
     printf("d8> ");
     Local<String> input = Shell::ReadFromStdin(isolate);
     if (input.IsEmpty()) break;
-    ExecuteString(isolate, input, name, true, true);
+    ExecuteString(isolate, input, name, kPrintResult, kReportExceptions,
+                  kProcessMessageQueue);
   }
   printf("\n");
   // We need to explicitly clean up the module embedder data for
@@ -2431,7 +2436,9 @@ void SourceGroup::Execute(Isolate* isolate) {
           String::NewFromUtf8(isolate, argv_[i + 1], NewStringType::kNormal)
               .ToLocalChecked();
       Shell::options.script_executed = true;
-      if (!Shell::ExecuteString(isolate, source, file_name, false, true)) {
+      if (!Shell::ExecuteString(isolate, source, file_name,
+                                Shell::kNoPrintResult, Shell::kReportExceptions,
+                                Shell::kNoProcessMessageQueue)) {
         exception_was_thrown = true;
         break;
       }
@@ -2462,7 +2469,9 @@ void SourceGroup::Execute(Isolate* isolate) {
       Shell::Exit(1);
     }
     Shell::options.script_executed = true;
-    if (!Shell::ExecuteString(isolate, source, file_name, false, true)) {
+    if (!Shell::ExecuteString(isolate, source, file_name, Shell::kNoPrintResult,
+                              Shell::kReportExceptions,
+                              Shell::kProcessMessageQueue)) {
       exception_was_thrown = true;
       break;
     }
@@ -2670,7 +2679,9 @@ void Worker::ExecuteInThread() {
         Local<String> source =
             String::NewFromUtf8(isolate, script_, NewStringType::kNormal)
                 .ToLocalChecked();
-        if (Shell::ExecuteString(isolate, source, file_name, false, true)) {
+        if (Shell::ExecuteString(
+                isolate, source, file_name, Shell::kNoPrintResult,
+                Shell::kReportExceptions, Shell::kProcessMessageQueue)) {
           // Get the message handler
           Local<Value> onmessage =
               global->Get(context, String::NewFromUtf8(isolate, "onmessage",

src/d8.h

@@ -356,9 +356,20 @@ class ShellOptions {
 
 class Shell : public i::AllStatic {
  public:
+  enum PrintResult : bool { kPrintResult = true, kNoPrintResult = false };
+  enum ReportExceptions : bool {
+    kReportExceptions = true,
+    kNoReportExceptions = false
+  };
+  enum ProcessMessageQueue : bool {
+    kProcessMessageQueue = true,
+    kNoProcessMessageQueue = false
+  };
+
   static bool ExecuteString(Isolate* isolate, Local<String> source,
-                            Local<Value> name, bool print_result,
-                            bool report_exceptions);
+                            Local<Value> name, PrintResult print_result,
+                            ReportExceptions report_exceptions,
+                            ProcessMessageQueue process_message_queue);
   static bool ExecuteModule(Isolate* isolate, const char* file_name);
   static void ReportException(Isolate* isolate, TryCatch* try_catch);
   static Local<String> ReadFile(Isolate* isolate, const char* name);