Handle load errors in deferred code

runtime/vm/dart_api_impl.cc

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "include/dart_api.h"
 #include "include/dart_mirrors_api.h"
 #include "include/dart_native_api.h"
 
 #include "platform/assert.h"
 #include "vm/bigint_operations.h"
@@ skipping 4775 matching lines @@
                             script.kind() == RawScript::kLibraryTag);
   if (update_lib_status) {
     lib.SetLoadInProgress();
   }
   ASSERT(isolate != NULL);
   const Error& error = Error::Handle(isolate, Compiler::Compile(lib, script));
   if (error.IsNull()) {
     *result = Api::NewHandle(isolate, lib.raw());
   } else {
     *result = Api::NewHandle(isolate, error.raw());
-    lib.SetLoadError();
+    // Compilation errors are not Dart instances, so just mark the library
+    // as having failed to load without providing an error instance.
+    lib.SetLoadError(Instance::Handle());
   }
 }
 
 
 DART_EXPORT Dart_Handle Dart_LoadScript(Dart_Handle url,
                                         Dart_Handle source,
                                         intptr_t line_offset,
                                         intptr_t col_offset) {
   Isolate* isolate = Isolate::Current();
   DARTSCOPE(isolate);
@@ skipping 214 matching lines @@
       Library::Handle(isolate, Library::LookupLibrary(url_str));
   if (library.IsNull()) {
     return Api::NewError("%s: library '%s' not found.",
                          CURRENT_FUNC, url_str.ToCString());
   } else {
     return Api::NewHandle(isolate, library.raw());
   }
 }
 
 
+DART_EXPORT Dart_Handle Dart_LibraryHandleError(Dart_Handle library_in,
+                                                Dart_Handle error_in) {
+  Isolate* isolate = Isolate::Current();
+  DARTSCOPE(isolate);
+
+  const Library& lib = Api::UnwrapLibraryHandle(isolate, library_in);
+  if (lib.IsNull()) {
+    RETURN_TYPE_ERROR(isolate, library_in, Library);
+  }
+  const Instance& err = Api::UnwrapInstanceHandle(isolate, error_in);
+  if (err.IsNull()) {
+    RETURN_TYPE_ERROR(isolate, error_in, Instance);
+  }
+  CHECK_CALLBACK_STATE(isolate);
+
+  const GrowableObjectArray& pending_deferred_loads =
+      GrowableObjectArray::Handle(
+          isolate->object_store()->pending_deferred_loads());
+  for (intptr_t i = 0; i < pending_deferred_loads.Length(); i++) {
+    if (pending_deferred_loads.At(i) == lib.raw()) {
+      lib.SetLoadError(err);
+      return Api::Null();
+    }
+  }
+  return error_in;
+}
+
+
 DART_EXPORT Dart_Handle Dart_LoadLibrary(Dart_Handle url,
                                          Dart_Handle source) {
   Isolate* isolate = Isolate::Current();
   DARTSCOPE(isolate);
   TIMERSCOPE(isolate, time_script_loading);
   const String& url_str = Api::UnwrapStringHandle(isolate, url);
   if (url_str.IsNull()) {
     RETURN_TYPE_ERROR(isolate, url, String);
   }
   const String& source_str = Api::UnwrapStringHandle(isolate, source);
   if (source_str.IsNull()) {
     RETURN_TYPE_ERROR(isolate, source, String);
   }
   CHECK_CALLBACK_STATE(isolate);
 
   NoHeapGrowthControlScope no_growth_control;
 
   Library& library = Library::Handle(isolate, Library::LookupLibrary(url_str));
   if (library.IsNull()) {
     library = Library::New(url_str);
     library.Register();
   } else if (library.LoadInProgress() ||
       library.Loaded() ||
-      library.LoadError()) {
+      library.LoadFailed()) {
     // The source for this library has either been loaded or is in the
     // process of loading.  Return an error.
     return Api::NewError("%s: library '%s' has already been loaded.",
                          CURRENT_FUNC, url_str.ToCString());
   }
   const Script& script = Script::Handle(
       isolate, Script::New(url_str, source_str, RawScript::kLibraryTag));
   Dart_Handle result;
   CompileSource(isolate, library, script, &result);
   // Propagate the error out right now.
@@ skipping 140 matching lines @@
     const String& function_name =
         String::Handle(isolate, String::New("_completeDeferredLoads"));
     const Function& function =
         Function::Handle(isolate,
                          corelib.LookupFunctionAllowPrivate(function_name));
     ASSERT(!function.IsNull());
     const Array& args = Array::empty_array();
 
     const Object& res =
         Object::Handle(isolate, DartEntry::InvokeFunction(function, args));
+    isolate->object_store()->clear_pending_deferred_loads();
     if (res.IsError() || res.IsUnhandledException()) {
       return Api::NewHandle(isolate, res.raw());
     }
   }
   return Api::Success();
 }
 
 
 DART_EXPORT Dart_Handle Dart_SetNativeResolver(
     Dart_Handle library,
@@ skipping 77 matching lines @@
 
 
 DART_EXPORT void Dart_RegisterRootServiceRequestCallback(
     const char* name,
     Dart_ServiceRequestCallback callback,
     void* user_data) {
   Service::RegisterRootEmbedderCallback(name, callback, user_data);
 }
 
 }  // namespace dart