Support ReadableByteStreamController in stream piping

Signed-off-by: Taym Haddadi <haddadi.taym@gmail.com>

components/script/dom/readablestream.rs

@@ -16,6 +16,7 @@ use js::rust::{
     MutableHandleValue as SafeMutableHandleValue,
 };
 use js::typedarray::ArrayBufferViewU8;
+use script_bindings::codegen::GenericBindings::ReadableStreamBYOBReaderBinding::ReadableStreamBYOBReaderMethods;
 
 use crate::dom::bindings::codegen::Bindings::QueuingStrategyBinding::QueuingStrategy;
 use crate::dom::bindings::codegen::Bindings::ReadableStreamBinding::{
@@ -101,8 +102,7 @@ impl js::gc::Rootable for PipeTo {}
 #[cfg_attr(crown, crown::unrooted_must_root_lint::must_root)]
 struct PipeTo {
     /// <https://streams.spec.whatwg.org/#ref-for-readablestream%E2%91%A7%E2%91%A0>
-    reader: Dom<ReadableStreamDefaultReader>,
+    reader: ReaderType,
-
     /// <https://streams.spec.whatwg.org/#ref-for-acquire-writable-stream-default-writer>
     writer: Dom<WritableStreamDefaultWriter>,
 
@@ -157,7 +157,7 @@ impl Callback for PipeTo {
     /// - the state of a stored promise(in some cases).
     #[allow(unsafe_code)]
     fn callback(&self, cx: SafeJSContext, result: SafeHandleValue, realm: InRealm, can_gc: CanGc) {
-        let global = self.reader.global();
+        let global = self.writer.global();
 
         // Note: we only care about the result of writes when they are rejected,
         // and the error is accessed not through handlers,
@@ -320,7 +320,7 @@ impl PipeTo {
             // Note: if the writer is not ready,
             // in order to ensure progress we must
             // also react to the closure of the source(because source may close empty).
-            let closed_promise = self.reader.Closed();
+            let closed_promise = self.reader.closed();
             closed_promise.append_native_handler(&handler, realm, can_gc);
         }
     }
@@ -328,7 +328,7 @@ impl PipeTo {
     /// Read a chunk
     fn read_chunk(&self, global: &GlobalScope, realm: InRealm, can_gc: CanGc) {
         *self.state.borrow_mut() = PipeToState::PendingRead;
-        let chunk_promise = self.reader.Read(can_gc);
+        let chunk_promise = self.reader.read(can_gc);
         let handler = PromiseNativeHandler::new(
             global,
             Some(Box::new(self.clone())),
@@ -657,8 +657,6 @@ impl PipeTo {
 
         // If reader implements ReadableStreamBYOBReader,
         // perform ! ReadableStreamBYOBReaderRelease(reader).
-        // TODO.
-
         // Otherwise, perform ! ReadableStreamDefaultReaderRelease(reader).
         self.reader
             .release(can_gc)
@@ -731,6 +729,8 @@ pub(crate) enum ControllerType {
     Default(MutNullableDom<ReadableStreamDefaultController>),
 }
 
+impl js::gc::Rootable for ReaderType {}
+
 /// <https://streams.spec.whatwg.org/#readablestream-readerr>
 #[derive(JSTraceable, MallocSizeOf)]
 #[cfg_attr(crown, crown::unrooted_must_root_lint::must_root)]
@@ -742,6 +742,57 @@ pub(crate) enum ReaderType {
     Default(MutNullableDom<ReadableStreamDefaultReader>),
 }
 
+impl Clone for ReaderType {
+    #[cfg_attr(crown, allow(crown::unrooted_must_root))]
+    fn clone(&self) -> Self {
+        match self {
+            ReaderType::BYOB(reader) => ReaderType::BYOB(MutNullableDom::new(Some(
+                &reader.get().expect("Reader should be set"),
+            ))),
+            ReaderType::Default(reader) => ReaderType::Default(MutNullableDom::new(Some(
+                &reader.get().expect("Reader should be set"),
+            ))),
+        }
+    }
+}
+
+impl ReaderType {
+    /// Get the stream from the reader.
+    pub(crate) fn get_stream(&self) -> Option<DomRoot<ReadableStream>> {
+        match self {
+            ReaderType::BYOB(reader) => reader.get().expect("Reader should be set").get_stream(),
+            ReaderType::Default(reader) => reader.get().expect("Reader should be set").get_stream(),
+        }
+    }
+
+    /// Release the reader.
+    pub(crate) fn release(&self, can_gc: CanGc) -> Fallible<()> {
+        match self {
+            ReaderType::BYOB(reader) => reader.get().expect("Reader should be set").release(can_gc),
+            ReaderType::Default(reader) => {
+                reader.get().expect("Reader should be set").release(can_gc)
+            },
+        }
+    }
+
+    // get reader Closed promise
+    pub(crate) fn closed(&self) -> Rc<Promise> {
+        match self {
+            ReaderType::BYOB(reader) => reader.get().expect("Reader should be set").Closed(),
+            ReaderType::Default(reader) => reader.get().expect("Reader should be set").Closed(),
+        }
+    }
+
+    // Read
+    pub(crate) fn read(&self, can_gc: CanGc) -> Rc<Promise> {
+        match self {
+            ReaderType::BYOB(_) => {
+                unreachable!("Native reading of a chunk can only be done with a default reader.")
+            },
+            ReaderType::Default(reader) => reader.get().expect("Reader should be set").Read(can_gc),
+        }
+    }
+}
 impl Eq for ReaderType {}
 impl PartialEq for ReaderType {
     fn eq(&self, other: &Self) -> bool {
@@ -1634,17 +1685,6 @@ impl ReadableStream {
         // Assert: ! IsWritableStreamLocked(dest) is false.
         assert!(!dest.is_locked());
 
-        // If source.[[controller]] implements ReadableByteStreamController,
-        // let reader be either ! AcquireReadableStreamBYOBReader(source)
-        // or ! AcquireReadableStreamDefaultReader(source),
-        // at the user agent’s discretion.
-        // Note: for now only using default readers.
-
-        // Otherwise, let reader be ! AcquireReadableStreamDefaultReader(source).
-        let reader = self
-            .acquire_default_reader(can_gc)
-            .expect("Acquiring a default reader for pipe_to cannot fail");
-
         // Let writer be ! AcquireWritableStreamDefaultWriter(dest).
         let writer = dest
             .aquire_default_writer(cx, global, can_gc)
@@ -1664,7 +1704,22 @@ impl ReadableStream {
 
         // In parallel, but not really, using reader and writer, read all chunks from source and write them to dest.
         rooted!(in(*cx) let pipe_to = PipeTo {
-            reader: Dom::from_ref(&reader),
+            // If source.[[controller]] implements ReadableByteStreamController,
+            // let reader be either ! AcquireReadableStreamBYOBReader(source)
+            // or ! AcquireReadableStreamDefaultReader(source),
+            // at the user agent’s discretion.
+            // Otherwise, let reader be ! AcquireReadableStreamDefaultReader(source).
+            reader: if self.has_byob_reader() {
+                let byob_reader = &self
+                    .acquire_byob_reader(can_gc)
+                    .expect("Acquiring a BYOB reader for pipe_to should not fail");
+                ReaderType::BYOB(MutNullableDom::new(Some(byob_reader)))
+            } else {
+                let default_reader = &self
+                    .acquire_default_reader(can_gc)
+                    .expect("Acquiring a default reader for pipe_to should not fail");
+                ReaderType::Default(MutNullableDom::new(Some(default_reader)))
+            },
             writer: Dom::from_ref(&writer),
             pending_writes: Default::default(),
             state: Default::default(),