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// Copyright 2018-2022 the Deno authors. All rights reserved. MIT license.// Copyright Joyent and Node contributors. All rights reserved. MIT license.// deno-lint-ignore-file
const kIsDisturbed = Symbol("kIsDisturbed");
function isReadableNodeStream(obj) {  return !!(    obj &&    typeof obj.pipe === "function" &&    typeof obj.on === "function" &&    (!obj._writableState || obj._readableState?.readable !== false) && // Duplex    (!obj._writableState || obj._readableState) // Writable has .pipe.  );}
function isWritableNodeStream(obj) {  return !!(    obj &&    typeof obj.write === "function" &&    typeof obj.on === "function" &&    (!obj._readableState || obj._writableState?.writable !== false) // Duplex  );}
function isDuplexNodeStream(obj) {  return !!(    obj &&    (typeof obj.pipe === "function" && obj._readableState) &&    typeof obj.on === "function" &&    typeof obj.write === "function"  );}
function isNodeStream(obj) {  return (    obj &&    (      obj._readableState ||      obj._writableState ||      (typeof obj.write === "function" && typeof obj.on === "function") ||      (typeof obj.pipe === "function" && typeof obj.on === "function")    )  );}
function isDestroyed(stream) {  if (!isNodeStream(stream)) return null;  const wState = stream._writableState;  const rState = stream._readableState;  const state = wState || rState;  return !!(stream.destroyed || state?.destroyed);}
// Have been end():d.function isWritableEnded(stream) {  if (!isWritableNodeStream(stream)) return null;  if (stream.writableEnded === true) return true;  const wState = stream._writableState;  if (wState?.errored) return false;  if (typeof wState?.ended !== "boolean") return null;  return wState.ended;}
// Have emitted 'finish'.function isWritableFinished(stream, strict) {  if (!isWritableNodeStream(stream)) return null;  if (stream.writableFinished === true) return true;  const wState = stream._writableState;  if (wState?.errored) return false;  if (typeof wState?.finished !== "boolean") return null;  return !!(    wState.finished ||    (strict === false && wState.ended === true && wState.length === 0)  );}
// Have been push(null):d.function isReadableEnded(stream) {  if (!isReadableNodeStream(stream)) return null;  if (stream.readableEnded === true) return true;  const rState = stream._readableState;  if (!rState || rState.errored) return false;  if (typeof rState?.ended !== "boolean") return null;  return rState.ended;}
// Have emitted 'end'.function isReadableFinished(stream, strict) {  if (!isReadableNodeStream(stream)) return null;  const rState = stream._readableState;  if (rState?.errored) return false;  if (typeof rState?.endEmitted !== "boolean") return null;  return !!(    rState.endEmitted ||    (strict === false && rState.ended === true && rState.length === 0)  );}
function isDisturbed(stream) {  return !!(stream && (    stream.readableDidRead ||    stream.readableAborted ||    stream[kIsDisturbed]  ));}
function isReadable(stream) {  const r = isReadableNodeStream(stream);  if (r === null || typeof stream?.readable !== "boolean") return null;  if (isDestroyed(stream)) return false;  return r && stream.readable && !isReadableFinished(stream);}
function isWritable(stream) {  const r = isWritableNodeStream(stream);  if (r === null || typeof stream?.writable !== "boolean") return null;  if (isDestroyed(stream)) return false;  return r && stream.writable && !isWritableEnded(stream);}
function isFinished(stream, opts) {  if (!isNodeStream(stream)) {    return null;  }
  if (isDestroyed(stream)) {    return true;  }
  if (opts?.readable !== false && isReadable(stream)) {    return false;  }
  if (opts?.writable !== false && isWritable(stream)) {    return false;  }
  return true;}
function isClosed(stream) {  if (!isNodeStream(stream)) {    return null;  }
  const wState = stream._writableState;  const rState = stream._readableState;
  if (    typeof wState?.closed === "boolean" ||    typeof rState?.closed === "boolean"  ) {    return wState?.closed || rState?.closed;  }
  if (typeof stream._closed === "boolean" && isOutgoingMessage(stream)) {    return stream._closed;  }
  return null;}
function isOutgoingMessage(stream) {  return (    typeof stream._closed === "boolean" &&    typeof stream._defaultKeepAlive === "boolean" &&    typeof stream._removedConnection === "boolean" &&    typeof stream._removedContLen === "boolean"  );}
function isServerResponse(stream) {  return (    typeof stream._sent100 === "boolean" &&    isOutgoingMessage(stream)  );}
function isServerRequest(stream) {  return (    typeof stream._consuming === "boolean" &&    typeof stream._dumped === "boolean" &&    stream.req?.upgradeOrConnect === undefined  );}
function willEmitClose(stream) {  if (!isNodeStream(stream)) return null;
  const wState = stream._writableState;  const rState = stream._readableState;  const state = wState || rState;
  return (!state && isServerResponse(stream)) || !!(    state &&    state.autoDestroy &&    state.emitClose &&    state.closed === false  );}
export default {  isDisturbed,  kIsDisturbed,  isClosed,  isDestroyed,  isDuplexNodeStream,  isFinished,  isReadable,  isReadableNodeStream,  isReadableEnded,  isReadableFinished,  isNodeStream,  isWritable,  isWritableNodeStream,  isWritableEnded,  isWritableFinished,  isServerRequest,  isServerResponse,  willEmitClose,};export {  isClosed,  isDestroyed,  isDisturbed,  isDuplexNodeStream,  isFinished,  isNodeStream,  isReadable,  isReadableEnded,  isReadableFinished,  isReadableNodeStream,  isServerRequest,  isServerResponse,  isWritable,  isWritableEnded,  isWritableFinished,  isWritableNodeStream,  kIsDisturbed,  willEmitClose,};