From eeab147fc2959fe855ccefeec7acdc252aad4678 Mon Sep 17 00:00:00 2001
From: Tomasz Andrzejak <andreiltd@gmail.com>
Date: Mon, 23 Dec 2024 21:12:33 +0100
Subject: [PATCH] Add File::create function

---
 builtins/web/blob.cpp |  4 ++++
 builtins/web/blob.h   |  2 +-
 builtins/web/file.cpp | 43 +++++++++++++++++++++++++++++--------------
 builtins/web/file.h   |  1 +
 4 files changed, 35 insertions(+), 15 deletions(-)

diff --git a/builtins/web/blob.cpp b/builtins/web/blob.cpp
index c760b4a..aa5b35a 100644
--- a/builtins/web/blob.cpp
+++ b/builtins/web/blob.cpp
@@ -677,6 +677,8 @@ JSObject *Blob::create(JSContext *cx, UniqueChars data, size_t data_len, HandleS
   SetReservedSlot(self, static_cast<uint32_t>(Slots::Type), JS::StringValue(type));
   SetReservedSlot(self, static_cast<uint32_t>(Slots::Endings), JS::Int32Value(LineEndings::Transparent));
   SetReservedSlot(self, static_cast<uint32_t>(Slots::Readers), JS::PrivateValue(new ReadersMap));
+  SetReservedSlot(self, static_cast<uint32_t>(Slots::Reserved1), JS::NullValue());
+  SetReservedSlot(self, static_cast<uint32_t>(Slots::Reserved2), JS::NullValue());
   return self;
 }
 
@@ -695,6 +697,8 @@ bool Blob::constructor(JSContext *cx, unsigned argc, JS::Value *vp) {
   SetReservedSlot(self, static_cast<uint32_t>(Slots::Endings), JS::Int32Value(LineEndings::Transparent));
   SetReservedSlot(self, static_cast<uint32_t>(Slots::Data), JS::PrivateValue(new ByteBuffer));
   SetReservedSlot(self, static_cast<uint32_t>(Slots::Readers), JS::PrivateValue(new ReadersMap));
+  SetReservedSlot(self, static_cast<uint32_t>(Slots::Reserved1), JS::NullValue());
+  SetReservedSlot(self, static_cast<uint32_t>(Slots::Reserved2), JS::NullValue());
 
   // Walk the blob parts and append them to the blob's buffer.
   if (blobParts.isNull()) {
diff --git a/builtins/web/blob.h b/builtins/web/blob.h
index 857b789..27c3694 100644
--- a/builtins/web/blob.h
+++ b/builtins/web/blob.h
@@ -51,7 +51,7 @@ class Blob : public TraceableBuiltinImpl<Blob> {
   static const JSPropertySpec properties[];
 
   static constexpr unsigned ctor_length = 0;
-  enum Slots { Data, Type, Endings, Readers, Reserved2, Reserved1, Count };
+  enum Slots { Data, Type, Endings, Readers, Reserved1, Reserved2, Count };
   enum LineEndings { Transparent, Native };
 
   using HeapObj = Heap<JSObject *>;
diff --git a/builtins/web/file.cpp b/builtins/web/file.cpp
index 435c085..0b36b36 100644
--- a/builtins/web/file.cpp
+++ b/builtins/web/file.cpp
@@ -102,26 +102,26 @@ bool File::lastModified_get(JSContext *cx, unsigned argc, JS::Value *vp) {
 }
 
 bool File::is_instance(const JSObject *obj) {
-  return obj != nullptr && (JS::GetClass(obj) == &class_ || JS::GetClass(obj) == &Blob::class_);
+  return obj != nullptr
+    && JS::GetClass(obj) == &Blob::class_
+    && !JS::GetReservedSlot(
+      (JSObject *)obj,
+      static_cast<size_t>(ParentSlots::Name)).isNullOrUndefined();
 }
 
-bool File::is_instance(const Value val) { return val.isObject() && is_instance(&val.toObject()); }
-
-bool File::constructor(JSContext *cx, unsigned argc, JS::Value *vp) {
-  CTOR_HEADER("File", 2);
-
-  RootedValue fileBits(cx, args.get(0));
-  RootedValue fileName(cx, args.get(1));
-  RootedValue opts(cx, args.get(2));
+bool File::is_instance(const Value val) {
+  return val.isObject() && is_instance(&val.toObject());
+}
 
+JSObject *File::create(JSContext *cx, HandleValue fileBits, HandleValue fileName, HandleValue opts) {
   RootedObject blob_ctor(cx, JS_GetConstructor(cx, Blob::proto_obj));
   if (!blob_ctor) {
-    return false;
+    return nullptr;
   }
 
   RootedObject this_ctor(cx, JS_GetConstructor(cx, File::proto_obj));
   if (!this_ctor) {
-    return false;
+    return nullptr;
   }
 
   MOZ_ASSERT(JS::IsConstructor(blob_ctor));
@@ -138,13 +138,13 @@ bool File::constructor(JSContext *cx, unsigned argc, JS::Value *vp) {
   RootedValue blob_ctor_val(cx, JS::ObjectValue(*blob_ctor));
   RootedObject self(cx);
   if (!JS::Construct(cx, blob_ctor_val, this_ctor, blob_args, &self)) {
-    return false;
+    return nullptr;
   }
 
   // 2. Let n be the fileName argument to the constructor.
   RootedString name(cx, JS::ToString(cx, fileName));
   if (!name) {
-    return false;
+    return nullptr;
   }
 
   // 3. Process `FilePropertyBag` dictionary argument by running the following substeps:
@@ -154,7 +154,7 @@ bool File::constructor(JSContext *cx, unsigned argc, JS::Value *vp) {
   //  milliseconds since the Unix Epoch.
   RootedValue lastModified(cx);
   if (!init_last_modified(cx, opts, &lastModified)) {
-    return false;
+    return nullptr;
   }
 
   // Return a new File object F such that:
@@ -169,6 +169,21 @@ bool File::constructor(JSContext *cx, unsigned argc, JS::Value *vp) {
   SetReservedSlot(self, static_cast<uint32_t>(ParentSlots::Name), JS::StringValue(name));
   SetReservedSlot(self, static_cast<uint32_t>(ParentSlots::LastModified), lastModified);
 
+  return self;
+}
+
+bool File::constructor(JSContext *cx, unsigned argc, JS::Value *vp) {
+  CTOR_HEADER("File", 2);
+
+  RootedValue fileBits(cx, args.get(0));
+  RootedValue fileName(cx, args.get(1));
+  RootedValue opts(cx, args.get(2));
+
+  RootedObject self(cx, create(cx, fileBits, fileName, opts));
+  if (!self) {
+    return false;
+  }
+
   args.rval().setObject(*self);
   return true;
 }
diff --git a/builtins/web/file.h b/builtins/web/file.h
index a3aaf08..05e7216 100644
--- a/builtins/web/file.h
+++ b/builtins/web/file.h
@@ -24,6 +24,7 @@ class File : public BuiltinImpl<File> {
   static bool is_instance(const JSObject *obj);
   static bool is_instance(const Value val);
 
+  static JSObject *create(JSContext *cx, HandleValue fileBits, HandleValue fileName, HandleValue opts);
   static bool init_class(JSContext *cx, HandleObject global);
   static bool constructor(JSContext *cx, unsigned argc, Value *vp);
 };