Bug 1734886 - Part 1: Throw when readably/writableType fields exist r=mgaudet

Differential Revision: https://phabricator.services.mozilla.com/D138825

dom/streams/TransformStream.cpp

@@ -40,8 +40,84 @@ already_AddRefed<TransformStream> TransformStream::Constructor(
     const Optional<JS::Handle<JSObject*>>& aTransformer,
     const QueuingStrategy& aWritableStrategy,
     const QueuingStrategy& aReadableStrategy, ErrorResult& aRv) {
+  // Step 1. If transformer is missing, set it to null.
+  JS::Rooted<JSObject*> transformerObj(
+      aGlobal.Context(),
+      aTransformer.WasPassed() ? aTransformer.Value() : nullptr);
+
+  // Step 2. Let transformerDict be transformer, converted to an IDL value of
+  // type Transformer.
+  Transformer transformerDict;
+  if (transformerObj) {
+    JS::Rooted<JS::Value> objValue(aGlobal.Context(),
+                                   JS::ObjectValue(*transformerObj));
+    dom::BindingCallContext callCx(aGlobal.Context(),
+                                   "TransformStream.constructor");
+    aRv.MightThrowJSException();
+    if (!transformerDict.Init(callCx, objValue)) {
+      aRv.StealExceptionFromJSContext(aGlobal.Context());
+      return nullptr;
+    }
+  }
+
+  // Step 3. If transformerDict["readableType"] exists, throw a RangeError
+  // exception.
+  if (!transformerDict.mReadableType.isUndefined()) {
+    aRv.ThrowRangeError(
+        "`readableType` is unsupported and preserved for future use");
+    return nullptr;
+  }
+
+  // Step 4. If transformerDict["writableType"] exists, throw a RangeError
+  // exception.
+  if (!transformerDict.mWritableType.isUndefined()) {
+    aRv.ThrowRangeError(
+        "`writableType` is unsupported and preserved for future use");
+    return nullptr;
+  }
+
+  // Step 5. Let readableHighWaterMark be ?
+  // ExtractHighWaterMark(readableStrategy, 0).
+  // TODO
+
+  // Step 6. Let readableSizeAlgorithm be !
+  // ExtractSizeAlgorithm(readableStrategy).
+  // TODO
+
+  // Step 7. Let writableHighWaterMark be ?
+  // ExtractHighWaterMark(writableStrategy, 1).
+  // TODO
+
+  // Step 8. Let writableSizeAlgorithm be !
+  // ExtractSizeAlgorithm(writableStrategy).
+  // TODO
+
+  // Step 9. Let startPromise be a new promise.
   nsCOMPtr<nsIGlobalObject> global = do_QueryInterface(aGlobal.GetAsSupports());
+  RefPtr<Promise> startPromise = Promise::Create(global, aRv);
+  if (aRv.Failed()) {
+    return nullptr;
+  }
+
+  // Step 10. Perform ! InitializeTransformStream(this, startPromise,
+  // writableHighWaterMark, writableSizeAlgorithm, readableHighWaterMark,
+  // readableSizeAlgorithm).
   RefPtr<TransformStream> transformStream = new TransformStream(global);
+  // TODO: Init()
+  if (aRv.Failed()) {
+    return nullptr;
+  }
+
+  // Step 11. Perform ?
+  // SetUpTransformStreamDefaultControllerFromTransformer(this, transformer,
+  // transformerDict).
+  // TODO
+
+  // Step 12. If transformerDict["start"] exists, then resolve startPromise with
+  // the result of invoking transformerDict["start"] with argument list «
+  // this.[[controller]] » and callback this value transformer.
+  // TODO
+
   return transformStream.forget();
 }
 

testing/web-platform/meta/streams/transform-streams/general.any.js.ini

@@ -53,12 +53,6 @@
   [start() should not be called twice]
     expected: FAIL
 
-  [specifying a defined readableType should throw]
-    expected: FAIL
-
-  [specifying a defined writableType should throw]
-    expected: FAIL
-
   [Subclassing TransformStream should work]
     expected: FAIL
 
@@ -118,12 +112,6 @@
   [start() should not be called twice]
     expected: FAIL
 
-  [specifying a defined readableType should throw]
-    expected: FAIL
-
-  [specifying a defined writableType should throw]
-    expected: FAIL
-
   [Subclassing TransformStream should work]
     expected: FAIL
 
@@ -183,12 +171,6 @@
   [start() should not be called twice]
     expected: FAIL
 
-  [specifying a defined readableType should throw]
-    expected: FAIL
-
-  [specifying a defined writableType should throw]
-    expected: FAIL
-
   [Subclassing TransformStream should work]
     expected: FAIL
 
@@ -248,11 +230,5 @@
   [start() should not be called twice]
     expected: FAIL
 
-  [specifying a defined readableType should throw]
-    expected: FAIL
-
-  [specifying a defined writableType should throw]
-    expected: FAIL
-
   [Subclassing TransformStream should work]
     expected: FAIL