Function ReadableStreamCancel

examples/io/streams/modules/streams.js:1326–1347

(stream, reason)

	reader.readRequests.push(readRequest);
}
function ReadableStreamCancel(stream, reason) {
	stream.disturbed = true;
	const state = stream.state;	
	if (state == "closed")
		return Promise.resolve(undefined);
	if (state == "errored")
		return Promise.reject(stream.storedError);
	ReadableStreamClose(stream);
	const reader = stream.reader;
	if (reader && ReadableStreamBYOBReaderBrand.has(reader.self)) {
		let readIntoRequests = reader.readIntoRequests;
		reader.readIntoRequests = [];
		readIntoRequests.forEach(readIntoRequest => {
			readIntoRequest.closeSteps(undefined);
		});
	}
	let promise = stream.controller.cancelSteps(reason);
	let then = promise.then(value => {
		return undefined;
	});
	return then;
}
function ReadableStreamClose(stream) {
	const state = stream.state;	
	assert(state == "readable");