libdeno: expose dynamic import (#2461)

1 files changed, 34 insertions, 0 deletions

diff --git a/core/libdeno/binding.cc b/core/libdeno/binding.cc
index 8001534ff..4aeb6003a 100644
--- a/core/libdeno/binding.cc
+++ b/core/libdeno/binding.cc
@@ -509,6 +509,38 @@ void HostInitializeImportMetaObjectCallback(v8::Local<v8::Context> context,
   meta->CreateDataProperty(context, v8_str("main"), v8_bool(main)).ToChecked();
 }
 
+v8::MaybeLocal<v8::Promise> HostImportModuleDynamicallyCallback(
+    v8::Local<v8::Context> context, v8::Local<v8::ScriptOrModule> referrer,
+    v8::Local<v8::String> specifier) {
+  auto* isolate = context->GetIsolate();
+  DenoIsolate* d = DenoIsolate::FromIsolate(isolate);
+  v8::Isolate::Scope isolate_scope(isolate);
+
+  v8::String::Utf8Value specifier_str(isolate, specifier);
+
+  auto referrer_name = referrer->GetResourceName();
+  v8::String::Utf8Value referrer_name_str(isolate, referrer_name);
+
+  // TODO(ry) I'm not sure what HostDefinedOptions is for or if we're ever going
+  // to use it. For now we check that it is not used. This check may need to be
+  // changed in the future.
+  auto host_defined_options = referrer->GetHostDefinedOptions();
+  CHECK_EQ(host_defined_options->Length(), 0);
+
+  v8::Local<v8::Promise::Resolver> resolver =
+      v8::Promise::Resolver::New(context).ToLocalChecked();
+
+  deno_dyn_import_id import_id = d->next_dyn_import_id_++;
+
+  d->dyn_import_map_.emplace(std::piecewise_construct,
+                             std::make_tuple(import_id),
+                             std::make_tuple(d->isolate_, resolver));
+
+  d->dyn_import_cb_(d->user_data_, *specifier_str, *referrer_name_str,
+                    import_id);
+  return resolver->GetPromise();
+}
+
 void DenoIsolate::AddIsolate(v8::Isolate* isolate) {
   isolate_ = isolate;
   isolate_->SetCaptureStackTraceForUncaughtExceptions(
@@ -518,6 +550,8 @@ void DenoIsolate::AddIsolate(v8::Isolate* isolate) {
   isolate_->AddMessageListener(MessageCallback);
   isolate->SetHostInitializeImportMetaObjectCallback(
       HostInitializeImportMetaObjectCallback);
+  isolate->SetHostImportModuleDynamicallyCallback(
+      HostImportModuleDynamicallyCallback);
 }
 
 }  // namespace deno