[ESNext] Implement DynamicImportCall

src/runtime/runtime-module.cc

 // Copyright 2016 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/runtime/runtime-utils.h"
 
 #include "src/arguments.h"
 #include "src/counters.h"
 #include "src/objects-inl.h"
 
 namespace v8 {
 namespace internal {
 
 RUNTIME_FUNCTION(Runtime_DynamicImportCall) {
   HandleScope scope(isolate);
-  DCHECK_EQ(1, args.length());
-  // TODO(gsathya): Implement ImportCall.
-  return isolate->heap()->undefined_value();
+  DCHECK_EQ(2, args.length());
+  CONVERT_ARG_HANDLE_CHECKED(String, source_url, 0);
+  CONVERT_ARG_HANDLE_CHECKED(Object, specifier, 1);
+  Handle<String> specifier_str;
+  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, specifier_str,
+                                     Object::ToString(isolate, specifier));
+  Handle<JSPromise> promise = isolate->factory()->NewJSPromise();
+  isolate->RunHostImportModuleDynamicallyCallback(source_url, specifier_str,
+                                                  promise);
+  return *promise;
 }
 
 RUNTIME_FUNCTION(Runtime_GetModuleNamespace) {
   HandleScope scope(isolate);
   DCHECK_EQ(1, args.length());
   CONVERT_SMI_ARG_CHECKED(module_request, 0);
   Handle<Module> module(isolate->context()->module());
   return *Module::GetModuleNamespace(module, module_request);
 }
 
@@ skipping 10 matching lines @@
   DCHECK_EQ(2, args.length());
   CONVERT_SMI_ARG_CHECKED(index, 0);
   CONVERT_ARG_HANDLE_CHECKED(Object, value, 1);
   Handle<Module> module(isolate->context()->module());
   Module::StoreVariable(module, index, value);
   return isolate->heap()->undefined_value();
 }
 
 }  // namespace internal
 }  // namespace v8