Issue #1442 - Part 3: Implement ReadableStream and associated classes in the JS engine. https://bugzilla.mozilla.org/show_bug.cgi?id=1272697

js/src/builtin/Stream.h

@@ -0,0 +1,118 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef builtin_Stream_h
+#define builtin_Stream_h
+
+#include "vm/NativeObject.h"
+
+namespace js {
+
+class AutoSetNewObjectMetadata;
+
+class ReadableStream : public NativeObject
+{
+  public:
+    static ReadableStream* createDefaultStream(JSContext* cx, HandleValue underlyingSource,
+                                               HandleValue size, HandleValue highWaterMark);
+    static ReadableStream* createByteStream(JSContext* cx, HandleValue underlyingSource,
+                                            HandleValue highWaterMark);
+
+    inline bool readable() const;
+    inline bool closed() const;
+    inline bool errored() const;
+    inline bool disturbed() const;
+
+    enum State {
+         Readable  = 1 << 0,
+         Closed    = 1 << 1,
+         Errored   = 1 << 2,
+         Disturbed = 1 << 3
+    };
+
+  private:
+    static ReadableStream* createStream(JSContext* cx);
+
+  public:
+    static bool constructor(JSContext* cx, unsigned argc, Value* vp);
+    static const ClassSpec classSpec_;
+    static const Class class_;
+    static const ClassSpec protoClassSpec_;
+    static const Class protoClass_;
+};
+
+class ReadableStreamDefaultReader : public NativeObject
+{
+  public:
+    static bool constructor(JSContext* cx, unsigned argc, Value* vp);
+    static const ClassSpec classSpec_;
+    static const Class class_;
+    static const ClassSpec protoClassSpec_;
+    static const Class protoClass_;
+};
+
+class ReadableStreamBYOBReader : public NativeObject
+{
+  public:
+    static bool constructor(JSContext* cx, unsigned argc, Value* vp);
+    static const ClassSpec classSpec_;
+    static const Class class_;
+    static const ClassSpec protoClassSpec_;
+    static const Class protoClass_;
+};
+
+class ReadableStreamDefaultController : public NativeObject
+{
+  public:
+    static bool constructor(JSContext* cx, unsigned argc, Value* vp);
+    static const ClassSpec classSpec_;
+    static const Class class_;
+    static const ClassSpec protoClassSpec_;
+    static const Class protoClass_;
+};
+
+class ReadableByteStreamController : public NativeObject
+{
+  public:
+    static bool constructor(JSContext* cx, unsigned argc, Value* vp);
+    static const ClassSpec classSpec_;
+    static const Class class_;
+    static const ClassSpec protoClassSpec_;
+    static const Class protoClass_;
+};
+
+class ReadableStreamBYOBRequest : public NativeObject
+{
+  public:
+    static bool constructor(JSContext* cx, unsigned argc, Value* vp);
+    static const ClassSpec classSpec_;
+    static const Class class_;
+    static const ClassSpec protoClassSpec_;
+    static const Class protoClass_;
+};
+
+class ByteLengthQueuingStrategy : public NativeObject
+{
+  public:
+    static bool constructor(JSContext* cx, unsigned argc, Value* vp);
+    static const ClassSpec classSpec_;
+    static const Class class_;
+    static const ClassSpec protoClassSpec_;
+    static const Class protoClass_;
+};
+
+class CountQueuingStrategy : public NativeObject
+{
+  public:
+    static bool constructor(JSContext* cx, unsigned argc, Value* vp);
+    static const ClassSpec classSpec_;
+    static const Class class_;
+    static const ClassSpec protoClassSpec_;
+    static const Class protoClass_;
+};
+
+} // namespace js
+
+#endif /* builtin_Stream_h */

js/src/builtin/TestingFunctions.cpp

@@ -1441,6 +1441,14 @@ RejectPromise(JSContext* cx, unsigned argc, Value* vp)
     return result;
 }
 
+static bool
+StreamsAreEnabled(JSContext* cx, unsigned argc, Value* vp)
+{
+    CallArgs args = CallArgsFromVp(argc, vp);
+    args.rval().setBoolean(cx->options().streams());
+    return true;
+}
+
 static unsigned finalizeCount = 0;
 
 static void
@@ -4178,6 +4186,10 @@ JS_FN_HELP("rejectPromise", RejectPromise, 2, 0,
 "rejectPromise(promise, reason)",
 "  Reject a Promise by calling the JSAPI function JS::RejectPromise."),
 
+JS_FN_HELP("streamsAreEnabled", StreamsAreEnabled, 0, 0,
+"streamsAreEnabled()",
+"  Returns a boolean indicating whether WHATWG Streams are enabled for the current compartment."),
+
     JS_FN_HELP("makeFinalizeObserver", MakeFinalizeObserver, 0, 0,
 "makeFinalizeObserver()",
 "  Get a special object whose finalization increases the counter returned\n"

js/src/js.msg

@@ -613,11 +613,38 @@ MSG_DEF(JSMSG_RETURN_NOT_CALLABLE,     0, JSEXN_TYPEERR, "property 'return' of i
 MSG_DEF(JSMSG_ITERATOR_NO_THROW,       0, JSEXN_TYPEERR, "iterator does not have a 'throw' method")
 
 // Async Iteration
-MSG_DEF(JSMSG_FOR_AWAIT_NOT_OF,        0, JSEXN_TYPEERR, "'for await' loop should be used with 'of'")
+MSG_DEF(JSMSG_FOR_AWAIT_NOT_OF,        0, JSEXN_SYNTAXERR, "'for await' loop should be used with 'of'")
 MSG_DEF(JSMSG_NOT_AN_ASYNC_GENERATOR,  0, JSEXN_TYPEERR, "Not an async generator")
 MSG_DEF(JSMSG_NOT_AN_ASYNC_ITERATOR,   0, JSEXN_TYPEERR, "Not an async from sync iterator")
 MSG_DEF(JSMSG_GET_ASYNC_ITER_RETURNED_PRIMITIVE, 0, JSEXN_TYPEERR, "[Symbol.asyncIterator]() returned a non-object value")
 
+// ReadableStream
+MSG_DEF(JSMSG_READABLESTREAM_UNDERLYINGSOURCE_TYPE_WRONG,0, JSEXN_RANGEERR,"'underlyingSource.type' must be \"bytes\" or undefined.")
+MSG_DEF(JSMSG_READABLESTREAM_INVALID_READER_MODE,        0, JSEXN_RANGEERR,"'mode' must be \"byob\" or undefined.")
+MSG_DEF(JSMSG_NUMBER_MUST_BE_FINITE_NON_NEGATIVE, 1, JSEXN_RANGEERR, "'{0}' must be a finite, non-negative number.")
+MSG_DEF(JSMSG_READABLEBYTESTREAMCONTROLLER_INVALID_BYTESWRITTEN, 0, JSEXN_RANGEERR, "'bytesWritten' exceeds remaining length.")
+MSG_DEF(JSMSG_READABLEBYTESTREAMCONTROLLER_INVALID_VIEW_SIZE, 0, JSEXN_RANGEERR, "view size does not match requested data.")
+MSG_DEF(JSMSG_READABLEBYTESTREAMCONTROLLER_INVALID_VIEW_OFFSET, 0, JSEXN_RANGEERR, "view offset does not match requested position.")
+MSG_DEF(JSMSG_READABLESTREAM_NOT_LOCKED,                 1, JSEXN_TYPEERR, "The ReadableStream method '{0}' may only be called on a locked stream.")
+MSG_DEF(JSMSG_READABLESTREAM_LOCKED,                     0, JSEXN_TYPEERR, "A Reader may only be created for an unlocked ReadableStream.")
+MSG_DEF(JSMSG_READABLESTREAM_NOT_BYTE_STREAM_CONTROLLER, 0, JSEXN_TYPEERR, "ReadableStream.getReader('byob') requires a ReadableByteStreamController.")
+MSG_DEF(JSMSG_READABLESTREAM_CONTROLLER_SET,             0, JSEXN_TYPEERR, "The ReadableStream already has a controller defined.")
+MSG_DEF(JSMSG_READABLESTREAMREADER_NOT_OWNED,            1, JSEXN_TYPEERR, "The ReadableStream reader method '{0}' may only be called on a reader owned by a stream.")
+MSG_DEF(JSMSG_READABLESTREAMREADER_NOT_EMPTY,            1, JSEXN_TYPEERR, "The ReadableStream reader method '{0}' may not be called on a reader with read requests.")
+MSG_DEF(JSMSG_READABLESTREAMBYOBREADER_READ_EMPTY_VIEW,  0, JSEXN_TYPEERR, "ReadableStreamBYOBReader.read() was passed an empty TypedArrayBuffer view.")
+MSG_DEF(JSMSG_READABLESTREAMREADER_RELEASED,             0, JSEXN_TYPEERR, "The ReadableStream reader was released.")
+MSG_DEF(JSMSG_READABLESTREAMCONTROLLER_CLOSED,           1, JSEXN_TYPEERR, "The ReadableStream controller method '{0}' called on a stream already closing.")
+MSG_DEF(JSMSG_READABLESTREAMCONTROLLER_NOT_READABLE,     1, JSEXN_TYPEERR, "The ReadableStream controller method '{0}' may only be called on a stream in the 'readable' state.")
+MSG_DEF(JSMSG_READABLEBYTESTREAMCONTROLLER_BAD_CHUNKSIZE,0, JSEXN_RANGEERR, "ReadableByteStreamController requires a positive integer or undefined for 'autoAllocateChunkSize'.")
+MSG_DEF(JSMSG_READABLEBYTESTREAMCONTROLLER_BAD_CHUNK,    0, JSEXN_TYPEERR, "ReadableByteStreamController passed a bad chunk.")
+MSG_DEF(JSMSG_READABLEBYTESTREAMCONTROLLER_CLOSE_PENDING_PULL, 0, JSEXN_TYPEERR, "The ReadableByteStreamController cannot be closed while the buffer is being filled.")
+MSG_DEF(JSMSG_READABLESTREAMBYOBREQUEST_NO_CONTROLLER,   1, JSEXN_TYPEERR, "ReadableStreamBYOBRequest method '{0}' called on a request with no controller.")
+MSG_DEF(JSMSG_READABLESTREAMBYOBREQUEST_RESPOND_CLOSED,  0, JSEXN_TYPEERR, "ReadableStreamBYOBRequest method 'respond' called with non-zero number of bytes with a closed controller.")
+MSG_DEF(JSMSG_READABLESTREAM_METHOD_NOT_IMPLEMENTED,     1, JSEXN_TYPEERR, "ReadableStream method {0} not yet implemented")
+
+// Other Stream-related
+MSG_DEF(JSMSG_STREAM_INVALID_HIGHWATERMARK,             0, JSEXN_RANGEERR, "'highWaterMark' must be a non-negative, non-NaN number.")
+
 // BigInt
 MSG_DEF(JSMSG_BIGINT_TO_NUMBER, 0, JSEXN_TYPEERR, "can't convert BigInt to number")
 MSG_DEF(JSMSG_NUMBER_TO_BIGINT, 0, JSEXN_RANGEERR, "can't convert non-finite number to BigInt")

js/src/jsfriendapi.h

@@ -2005,6 +2005,12 @@ JS_IsArrayBufferViewObject(JSObject* obj);
 extern JS_FRIEND_API(uint32_t)
 JS_GetArrayBufferViewByteLength(JSObject* obj);
 
+/**
+ * More generic name for JS_GetTypedArrayByteOffset to cover DataViews as well
+ */
+extern JS_FRIEND_API(uint32_t)
+JS_GetArrayBufferViewByteOffset(JSObject* obj);
+
 /*
  * Return a pointer to the start of the data referenced by a typed array. The
  * data is still owned by the typed array, and should not be modified on

js/src/jsnum.cpp

@@ -1003,6 +1003,13 @@ static const JSFunctionSpec number_methods[] = {
     JS_FS_END
 };
 
+bool
+js::IsInteger(const Value& val)
+{
+    return val.isInt32() ||
+           (mozilla::IsFinite(val.toDouble()) && JS::ToInteger(val.toDouble()) == val.toDouble());
+}
+
 // ES6 draft ES6 15.7.3.12
 static bool
 Number_isInteger(JSContext* cx, unsigned argc, Value* vp)
@@ -1013,9 +1020,7 @@ Number_isInteger(JSContext* cx, unsigned argc, Value* vp)
         return true;
     }
     Value val = args[0];
-    args.rval().setBoolean(val.isInt32() ||
-                           (mozilla::IsFinite(val.toDouble()) &&
-                            JS::ToInteger(val.toDouble()) == val.toDouble()));
+    args.rval().setBoolean(js::IsInteger(val));
     return true;
 }
 

js/src/jsnum.h

@@ -72,6 +72,10 @@ Int32ToString(ExclusiveContext* cx, int32_t i);
 extern JSAtom*
 Int32ToAtom(ExclusiveContext* cx, int32_t si);
 
+// ES6 15.7.3.12
+extern bool
+IsInteger(const Value& val);
+
 /*
  * Convert an integer or double (contained in the given value) to a string and
  * append to the given buffer.

js/src/jsprototypes.h

@@ -108,6 +108,17 @@ IF_SAB(real,imaginary)(Atomics, InitAtomicsClass, OCLASP(Atomics)) \
     imaginary(WasmMemory,       dummy,                  dummy) \
     imaginary(WasmTable,        dummy,                  dummy) \
     real(Promise,               InitViaClassSpec,       OCLASP(Promise)) \
+    real(ReadableStream,        InitViaClassSpec,       &js::ReadableStream::class_) \
+    real(ReadableStreamDefaultReader,         InitViaClassSpec, &js::ReadableStreamDefaultReader::class_) \
+    real(ReadableStreamBYOBReader,            InitViaClassSpec, &js::ReadableStreamBYOBReader::class_) \
+    real(ReadableStreamDefaultController,     InitViaClassSpec, &js::ReadableStreamDefaultController::class_) \
+    real(ReadableByteStreamController,        InitViaClassSpec, &js::ReadableByteStreamController::class_) \
+    real(ReadableStreamBYOBRequest,           InitViaClassSpec, &js::ReadableStreamBYOBRequest::class_) \
+    imaginary(WritableStream,   dummy,                  dummy) \
+    imaginary(WritableStreamDefaultWriter,    dummy,    dummy) \
+    imaginary(WritableStreamDefaultController,dummy,    dummy) \
+    real(ByteLengthQueuingStrategy,           InitViaClassSpec, &js::ByteLengthQueuingStrategy::class_) \
+    real(CountQueuingStrategy,  InitViaClassSpec,       &js::CountQueuingStrategy::class_) \
 
 #define JS_FOR_EACH_PROTOTYPE(macro) JS_FOR_PROTOTYPES(macro,macro)
 

js/src/moz.build

@@ -384,6 +384,7 @@ main_deunified_sources = [
 SOURCES += [
     'builtin/BigInt.cpp',
     'builtin/RegExp.cpp',
+    'builtin/Stream.cpp',
     'frontend/Parser.cpp',
     'gc/StoreBuffer.cpp',
     'jsarray.cpp',

js/src/vm/ArrayBufferObject.cpp

@@ -1891,6 +1891,17 @@ JS_GetArrayBufferViewByteLength(JSObject* obj)
            : obj->as<TypedArrayObject>().byteLength();
 }
 
+JS_FRIEND_API(uint32_t)
+JS_GetArrayBufferViewByteOffset(JSObject* obj)
+{
+    obj = CheckedUnwrap(obj);
+    if (!obj)
+        return 0;
+    return obj->is<DataViewObject>()
+           ? obj->as<DataViewObject>().byteOffset()
+           : obj->as<TypedArrayObject>().byteOffset();
+}
+
 JS_FRIEND_API(JSObject*)
 JS_GetObjectAsArrayBufferView(JSObject* obj, uint32_t* length, bool* isSharedMemory, uint8_t** data)
 {

js/src/vm/CommonPropertyNames.h

@@ -35,6 +35,7 @@
     macro(AsyncGeneratorFunction, AsyncGeneratorFunction, "AsyncGeneratorFunction") \
     macro(AsyncWrapped, AsyncWrapped, "AsyncWrapped") \
     macro(async, async, "async") \
+    macro(autoAllocateChunkSize, autoAllocateChunkSize, "autoAllocateChunkSize") \
     macro(await, await, "await") \
     macro(bigint64, bigint64, "bigint64") \
     macro(biguint64, biguint64, "biguint64") \
@@ -48,6 +49,7 @@
     macro(buffer, buffer, "buffer") \
     macro(builder, builder, "builder") \
     macro(by, by, "by") \
+    macro(byob, byob, "byob") \
     macro(byteAlignment, byteAlignment, "byteAlignment") \
     macro(byteLength, byteLength, "byteLength") \
     macro(byteOffset, byteOffset, "byteOffset") \
@@ -59,6 +61,7 @@
     macro(callee, callee, "callee") \
     macro(caller, caller, "caller") \
     macro(callFunction, callFunction, "callFunction") \
+    macro(cancel, cancel, "cancel") \
     macro(case, case_, "case") \
     macro(caseFirst, caseFirst, "caseFirst") \
     macro(catch, catch_, "catch") \
@@ -180,6 +183,7 @@
     macro(has, has, "has") \
     macro(hasOwn, hasOwn, "hasOwn") \
     macro(hasOwnProperty, hasOwnProperty, "hasOwnProperty") \
+    macro(highWaterMark, highWaterMark, "highWaterMark") \
     macro(hour, hour, "hour") \
     macro(hourCycle, hourCycle, "hourCycle") \
     macro(if, if_, "if") \
@@ -250,6 +254,7 @@
     macro(minusSign, minusSign, "minusSign") \
     macro(minute, minute, "minute") \
     macro(missingArguments, missingArguments, "missingArguments") \
+    macro(mode, mode, "mode") \
     macro(module, module, "module") \
     macro(Module, Module, "Module") \
     macro(ModuleInstantiate, ModuleInstantiate, "ModuleInstantiate") \
@@ -312,6 +317,7 @@
     macro(prototype, prototype, "prototype") \
     macro(proxy, proxy, "proxy") \
     macro(public, public_, "public") \
+    macro(pull, pull, "pull") \
     macro(raw, raw, "raw") \
     macro(reason, reason, "reason") \
     macro(RegExpFlagsGetter, RegExpFlagsGetter, "RegExpFlagsGetter") \
@@ -347,6 +353,7 @@
     macro(StarGeneratorNext, StarGeneratorNext, "StarGeneratorNext") \
     macro(StarGeneratorReturn, StarGeneratorReturn, "StarGeneratorReturn") \
     macro(StarGeneratorThrow, StarGeneratorThrow, "StarGeneratorThrow") \
+    macro(start, start, "start") \
     macro(startTimestamp, startTimestamp, "startTimestamp") \
     macro(state, state, "state") \
     macro(static, static_, "static") \

js/src/vm/GlobalObject.cpp

@@ -23,6 +23,7 @@
 #include "builtin/Promise.h"
 #include "builtin/RegExp.h"
 #include "builtin/SelfHostingDefines.h"
+#include "builtin/Stream.h"
 #include "builtin/SymbolObject.h"
 #include "builtin/TypedObject.h"
 #include "builtin/WeakMapObject.h"
@@ -98,6 +99,16 @@ GlobalObject::skipDeselectedConstructor(JSContext* cx, JSProtoKey key)
       case JSProto_WebAssembly:
         return !wasm::HasSupport(cx);
 
+      case JSProto_ReadableStream:
+      case JSProto_ReadableStreamDefaultReader:
+      case JSProto_ReadableStreamBYOBReader:
+      case JSProto_ReadableStreamDefaultController:
+      case JSProto_ReadableByteStreamController:
+      case JSProto_ReadableStreamBYOBRequest:
+      case JSProto_ByteLengthQueuingStrategy:
+      case JSProto_CountQueuingStrategy:
+        return !cx->options().streams();
+
 #ifdef ENABLE_SHARED_ARRAY_BUFFER
       case JSProto_Atomics:
       case JSProto_SharedArrayBuffer:

js/src/vm/SelfHosting.cpp

@@ -36,6 +36,7 @@
 #include "builtin/Promise.h"
 #include "builtin/Reflect.h"
 #include "builtin/SelfHostingDefines.h"
+#include "builtin/Stream.h"
 #include "builtin/TypedObject.h"
 #include "builtin/WeakSetObject.h"
 #include "gc/Marking.h"
@@ -71,7 +72,6 @@ using JS::AutoCheckCannotGC;
 using mozilla::IsInRange;
 using mozilla::Maybe;
 using mozilla::PodMove;
-using mozilla::Maybe;
 
 static void
 selfHosting_WarningReporter(JSContext* cx, JSErrorReport* report)
@@ -2490,6 +2490,9 @@ static const JSFunctionSpec intrinsic_functions[] = {
     JS_FN("CallWeakSetMethodIfWrapped",
           CallNonGenericSelfhostedMethod<Is<WeakSetObject>>, 2, 0),
 
+    JS_FN("IsReadableStreamBYOBRequest",
+          intrinsic_IsInstanceOfBuiltin<ReadableStreamBYOBRequest>, 1, 0),
+
     // See builtin/TypedObject.h for descriptors of the typedobj functions.
     JS_FN("NewOpaqueTypedObject",           js::NewOpaqueTypedObject, 1, 0),
     JS_FN("NewDerivedTypedObject",          js::NewDerivedTypedObject, 3, 0),