Lazy loading of deferred libraries

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 4959 matching lines @@
     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.LoadNotStarted()) {
+  } else if (!(library.LoadNotStarted() || library.LoadRequested())) {

[Ivan Posva, 2014/06/13 18:26:39]

Double negative makes it hard to understand what is going on here.

[hausner, 2014/06/13 22:41:57]

The comment was supposed to make it clearer. Changed to avoid double negatives.

     // 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.
   if (::Dart_IsError(result)) {
     return result;
   }
 
-  // If this is the dart:builtin library, register it with the VM.
-  if (url_str.Equals("dart:builtin")) {
+  // If this is the dart:_builtin library, register it with the VM.
+  if (url_str.Equals("dart:_builtin")) {
     isolate->object_store()->set_builtin_library(library);
     Dart_Handle state = Api::CheckIsolateState(isolate);
     if (::Dart_IsError(state)) {
       return state;
     }
   }
   return result;
 }
 
 
@@ skipping 25 matching lines @@
   const Namespace& import_ns = Namespace::Handle(
       Namespace::New(import_vm, Object::null_array(), Object::null_array()));
   if (prefix_vm.Length() == 0) {
     library_vm.AddImport(import_ns);
   } else {
     LibraryPrefix& library_prefix = LibraryPrefix::Handle();
     library_prefix = library_vm.LookupLocalLibraryPrefix(prefix_symbol);
     if (!library_prefix.IsNull()) {
       library_prefix.AddImport(import_ns);
     } else {
-      library_prefix = LibraryPrefix::New(prefix_symbol, import_ns, false);
+      library_prefix =
+          LibraryPrefix::New(prefix_symbol, import_ns, false, library_vm);
       library_vm.AddObject(library_prefix, prefix_symbol);
     }
   }
   return Api::Success();
 }
 
 
 DART_EXPORT Dart_Handle Dart_LoadSource(Dart_Handle library,
                                         Dart_Handle url,
                                         Dart_Handle source) {
@@ skipping 136 matching lines @@
 
 
 DART_EXPORT void Dart_RegisterRootServiceRequestCallback(
     const char* name,
     Dart_ServiceRequestCallback callback,
     void* user_data) {
   Service::RegisterRootEmbedderCallback(name, callback, user_data);
 }
 
 }  // namespace dart