Byte streams tracking bug

[tyoshino]

This is a tracking bug for progress on byte stream standardization.

Status:

• We've recently switched to adopt async read() (see Support reading bytes into buffers allocated by user code on platforms where only async read is available #253).
• ReadableByteStreams: missing APIs #176 is now obsolete.

Sub issues:

• Byte stream update, including reference implementation #361 Add reference impl
• Sync spec text with reference impl
  • Fill the internal slots section of ReadableByteStreamController #417 ReadableByteStreamController internal slots
  • Add spec texts for ReadableByteStreamController.close() and operations reachable from it #416 ReadableByteStreamController.close()
• Byte streams: write up design rationales and vision for how they are used/what they enable #177 Requirements doc: Summarized in the "Byte Streams" section in Requirements.md.
  • Generalized and precise flow/buffer control #301 Additional note about flow control design philosophy
• What should we call ReadableByteStream.prototype.getBYOBReader()? #294 Naming the reader getter methods
• What types does ReadableByteStream's reader's read(x) accept and return? #295 Return type and argument type of reader.read()
  • Accepts any ArrayBufferView
  • Returns { value: view, done }
  • BYOB: Returns (fulfill the promise with) the same type ArrayBufferView. E.g. if a Float32Array is given, return a Float32Array
  • Non-BYOB: Returns Uint8Array
    • Byte streams: write up design rationales and vision for how they are used/what they enable #177 (comment) Should the stream code enforce the return value to be Uint8Array?
    • View versus buffer yutakahirano/fetch-with-streams#35 (comment) should we let this be customizable?
• read(view) algorithm
  • Rough design: Byte streams: write up design rationales and vision for how they are used/what they enable #177 (comment)
  • How to handle non 1 BYTES_PER_ELEMENT ArrayBufferViews: What types does ReadableByteStream's reader's read(x) accept and return? #295 (comment)
  • Byte streams: write up design rationales and vision for how they are used/what they enable #177 (comment) just return the contents of the queue first
  • Regarding the queue existing at all: ReadableByteStream: should support an internal queue #353
  • Validate view Byte stream update, including reference implementation #361 (comment)
  • pull + pullInto or just pullInto ReadableByteStream: pull + pullInto or just pullInto #363
• Underlying byte source/controller design: return a promise vs. c.something: ReadableByteStream underlying source/controller design: return a promise vs. c.something #354
• enqueue() should check type or not
• Reference implementation/tests
• Add RBS to the templated tests
• Sync spec and reference implementation
• Use "perform" for abstract ops that cannot throw (do Use "perform" for abstract ops that cannot throw #366 for RBS)
• Pull based streams: ability to read $num items #74 will be closable once we have byte streams in the draft

[tyoshino]

Updating BinaryExtension.md at https://github.com/whatwg/streams/tree/asyncbytestream

[tyoshino]

Added definitions of methods on the BYOB reader https://github.com/whatwg/streams/blob/asyncbytestream/BinaryExtension.md

I tried to write the definitions without introducing detailed internal algorithm. @yutakahirano, could you please take a quick look?

[yutakahirano]

looks good

[tyoshino]

Thanks. Also added ReadableByteStreamReader.

[tyoshino]

I was trying to fulfill #312 in BinaryExtension.md in asyncbytestream branch. But I've moved the place to experiment that to PR #343. The BinaryExtension.md file in asyncbytestream branch still holds some draft and explainer texts.

[domenic]

The explainer texts are really nice IMO. We should consider maintaining something like them (probably for all the other classes too) in a docs/ directory or something. Or maybe just work on them in MDN, haha.

[tyoshino]

The explainer texts are really nice IMO. We should consider maintaining something like them (probably for all the other classes too) in a docs/ directory or something. Or maybe just work on them in MDN, haha.

Yeah. As a first step, done moving in PR #351

[tyoshino]

Spec text update just started at https://github.com/whatwg/streams/tree/rbscontroller

[tyoshino]

Added an item to discuss whether enqueue() should throw or not. Moved from https://code.google.com/p/chromium/issues/detail?id=577097#c4

[tyoshino]

enqueue() should check type or not

Now ReadableStreamBYOBController.enqueue() is specified to perform brand checking by checking presence of the [[ViewedArrayBuffer]] internal slot. Filled the checkbox in the OP.