Fix controller.error() race

index.bs

@@ -6077,8 +6077,12 @@ side=] of [=transform streams=].
  1. Perform ! [$TransformStreamDefaultControllerClearAlgorithms$](|controller|).
  1. [=React=] to |cancelPromise|:
  1. If |cancelPromise| was fulfilled, then:
- 1. Perform ! [$ReadableStreamDefaultControllerError$](|readable|.[=ReadableStream/[[controller]]=], |reason|).
- 1. [=Resolve=] |controller|.[=TransformStreamDefaultController/[[finishPromise]]=] with undefined.
+ 1. If |readable|.[=ReadableStream/[[state]]=] is "`errored`", [=reject=]
+ |controller|.[=TransformStreamDefaultController/[[finishPromise]]=] with 
+ |readable|.[=ReadableStream/[[storedError]]=].
+ 1. Otherwise:
+ 1. Perform ! [$ReadableStreamDefaultControllerError$](|readable|.[=ReadableStream/[[controller]]=], |reason|).
+ 1. [=Resolve=] |controller|.[=TransformStreamDefaultController/[[finishPromise]]=] with undefined.
  1. If |cancelPromise| was rejected with reason |r|, then:
  1. Perform ! [$ReadableStreamDefaultControllerError$](|readable|.[=ReadableStream/[[controller]]=], |r|).
  1. [=Reject=] |controller|.[=TransformStreamDefaultController/[[finishPromise]]=] with |r|.
@@ -6100,8 +6104,12 @@ side=] of [=transform streams=].
  1. Perform ! [$TransformStreamDefaultControllerClearAlgorithms$](|controller|).
  1. [=React=] to |flushPromise|:
  1. If |flushPromise| was fulfilled, then:
- 1. Perform ! [$ReadableStreamDefaultControllerClose$](|readable|.[=ReadableStream/[[controller]]=]).
- 1. [=Resolve=] |controller|.[=TransformStreamDefaultController/[[finishPromise]]=] with undefined.
+ 1. If |readable|.[=ReadableStream/[[state]]=] is "`errored`", [=reject=]
+ |controller|.[=TransformStreamDefaultController/[[finishPromise]]=] with 
+ |readable|.[=ReadableStream/[[storedError]]=].
+ 1. Otherwise:
+ 1. Perform ! [$ReadableStreamDefaultControllerClose$](|readable|.[=ReadableStream/[[controller]]=]).
+ 1. [=Resolve=] |controller|.[=TransformStreamDefaultController/[[finishPromise]]=] with undefined.
  1. If |flushPromise| was rejected with reason |r|, then:
  1. Perform ! [$ReadableStreamDefaultControllerError$](|readable|.[=ReadableStream/[[controller]]=], |r|).
  1. [=Reject=] |controller|.[=TransformStreamDefaultController/[[finishPromise]]=] with |r|.
@@ -6140,9 +6148,13 @@ side=] of [=transform streams=].
  1. Perform ! [$TransformStreamDefaultControllerClearAlgorithms$](|controller|).
  1. [=React=] to |cancelPromise|:
  1. If |cancelPromise| was fulfilled, then:
- 1. Perform ! [$WritableStreamDefaultControllerErrorIfNeeded$](|writable|.[=WritableStream/[[controller]]=], |reason|).
- 1. Perform ! [$TransformStreamUnblockWrite$](|stream|).
- 1. [=Resolve=] |controller|.[=TransformStreamDefaultController/[[finishPromise]]=] with undefined.
+ 1. If |writable|.[=WritableStream/[[state]]=] is "`errored`", [=reject=]
+ |controller|.[=TransformStreamDefaultController/[[finishPromise]]=] with 
+ |writable|.[=WritableStream/[[storedError]]=].
+ 1. Otherwise:
+ 1. Perform ! [$WritableStreamDefaultControllerErrorIfNeeded$](|writable|.[=WritableStream/[[controller]]=], |reason|).
+ 1. Perform ! [$TransformStreamUnblockWrite$](|stream|).
+ 1. [=Resolve=] |controller|.[=TransformStreamDefaultController/[[finishPromise]]=] with undefined.
  1. If |cancelPromise| was rejected with reason |r|, then:
  1. Perform ! [$WritableStreamDefaultControllerErrorIfNeeded$](|writable|.[=WritableStream/[[controller]]=], |r|).
  1. Perform ! [$TransformStreamUnblockWrite$](|stream|).

reference-implementation/lib/abstract-ops/transform-streams.js

@@ -249,8 +249,12 @@
  TransformStreamDefaultControllerClearAlgorithms(controller);
 
  uponPromise(cancelPromise, () => {
- ReadableStreamDefaultControllerError(readable._controller, reason);
- resolvePromise(controller._finishPromise);
+ if (readable._state === 'errored') {
+ rejectPromise(controller._finishPromise, readable._storedError);
+ } else {
+ ReadableStreamDefaultControllerError(readable._controller, reason);
+ resolvePromise(controller._finishPromise);
+ }
  }, r => {
  ReadableStreamDefaultControllerError(readable._controller, r);
  rejectPromise(controller._finishPromise, r);
@@ -278,8 +282,12 @@
  TransformStreamDefaultControllerClearAlgorithms(controller);
 
  uponPromise(flushPromise, () => {
- ReadableStreamDefaultControllerClose(readable._controller);
- resolvePromise(controller._finishPromise);
+ if (readable._state === 'errored') {
+ rejectPromise(controller._finishPromise, readable._storedError);
+ } else {
+ ReadableStreamDefaultControllerClose(readable._controller);
+ resolvePromise(controller._finishPromise); 
+ }
  }, r => {
  ReadableStreamDefaultControllerError(readable._controller, r);
  rejectPromise(controller._finishPromise, r);
@@ -324,9 +332,13 @@
  TransformStreamDefaultControllerClearAlgorithms(controller);
 
  uponPromise(cancelPromise, () => {
- WritableStreamDefaultControllerErrorIfNeeded(writable._controller, reason);
- TransformStreamUnblockWrite(stream);
- resolvePromise(controller._finishPromise);
+ if (writable._state === 'errored') {
+ rejectPromise(controller._finishPromise, writable._storedError);
+ } else {
+ WritableStreamDefaultControllerErrorIfNeeded(writable._controller, reason);
+ TransformStreamUnblockWrite(stream);
+ resolvePromise(controller._finishPromise);
+ }
  }, r => {
  WritableStreamDefaultControllerErrorIfNeeded(writable._controller, r);
  TransformStreamUnblockWrite(stream);