@brynjarrr/xchain-doge/lib/index.esm.js

Custom Doge client and utilities used by XChain clients

import { Network, standardFeeRates, calcFees, UTXOClient, TxType } from '@xchainjs/xchain-client';
import buffer from 'buffer';
import events from 'events';
import stream from 'stream';
import string_decoder$1 from 'string_decoder';
import crypto$1$1 from 'crypto';
import readableStream from 'readable-stream';
import axios from 'axios';

/*! *****************************************************************************
Copyright (c) Microsoft Corporation.

Permission to use, copy, modify, and/or distribute this software for any
purpose with or without fee is hereby granted.

THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
PERFORMANCE OF THIS SOFTWARE.
***************************************************************************** */

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function commonjsRequire () {
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/*! safe-buffer. MIT License. Feross Aboukhadijeh <https://feross.org/opensource> */
/* eslint-disable node/no-deprecated-api */

var Buffer = buffer.Buffer;

// alternative to using Object.keys for old browsers
function copyProps (src, dst) {
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}
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function SafeBuffer (arg, encodingOrOffset, length) {
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SafeBuffer.prototype = Object.create(Buffer.prototype);

// Copy static methods from Buffer
copyProps(Buffer, SafeBuffer);

SafeBuffer.from = function (arg, encodingOrOffset, length) {
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};

SafeBuffer.alloc = function (size, fill, encoding) {
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};

SafeBuffer.allocUnsafe = function (size) {
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};

SafeBuffer.allocUnsafeSlow = function (size) {
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};
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var safeBuffer_1 = safeBuffer.Buffer;

var streamBrowser = events.EventEmitter;

var _nodeResolve_empty = {};

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function ownKeys(object, enumerableOnly) { var keys = Object.keys(object); if (Object.getOwnPropertySymbols) { var symbols = Object.getOwnPropertySymbols(object); if (enumerableOnly) symbols = symbols.filter(function (sym) { return Object.getOwnPropertyDescriptor(object, sym).enumerable; }); keys.push.apply(keys, symbols); } return keys; }

function _objectSpread(target) { for (var i = 1; i < arguments.length; i++) { var source = arguments[i] != null ? arguments[i] : {}; if (i % 2) { ownKeys(Object(source), true).forEach(function (key) { _defineProperty(target, key, source[key]); }); } else if (Object.getOwnPropertyDescriptors) { Object.defineProperties(target, Object.getOwnPropertyDescriptors(source)); } else { ownKeys(Object(source)).forEach(function (key) { Object.defineProperty(target, key, Object.getOwnPropertyDescriptor(source, key)); }); } } return target; }

function _defineProperty(obj, key, value) { if (key in obj) { Object.defineProperty(obj, key, { value: value, enumerable: true, configurable: true, writable: true }); } else { obj[key] = value; } return obj; }

function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }

function _defineProperties(target, props) { for (var i = 0; i < props.length; i++) { var descriptor = props[i]; descriptor.enumerable = descriptor.enumerable || false; descriptor.configurable = true; if ("value" in descriptor) descriptor.writable = true; Object.defineProperty(target, descriptor.key, descriptor); } }

function _createClass(Constructor, protoProps, staticProps) { if (protoProps) _defineProperties(Constructor.prototype, protoProps); if (staticProps) _defineProperties(Constructor, staticProps); return Constructor; }

var Buffer$1 = buffer.Buffer;

var inspect = debugUtil.inspect;

var custom = inspect && inspect.custom || 'inspect';

function copyBuffer(src, target, offset) {
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var buffer_list =
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function () {
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function destroy(err, cb) {
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  var writableDestroyed = this._writableState && this._writableState.destroyed;

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  // to make it re-entrance safe in case destroy() is called within callbacks


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  } // if this is a duplex stream mark the writable part as destroyed as well


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  });

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}

function emitErrorAndCloseNT(self, err) {
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  emitCloseNT(self);
}

function emitCloseNT(self) {
  if (self._writableState && !self._writableState.emitClose) return;
  if (self._readableState && !self._readableState.emitClose) return;
  self.emit('close');
}

function undestroy() {
  if (this._readableState) {
    this._readableState.destroyed = false;
    this._readableState.reading = false;
    this._readableState.ended = false;
    this._readableState.endEmitted = false;
  }

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    this._writableState.destroyed = false;
    this._writableState.ended = false;
    this._writableState.ending = false;
    this._writableState.finalCalled = false;
    this._writableState.prefinished = false;
    this._writableState.finished = false;
    this._writableState.errorEmitted = false;
  }
}

function emitErrorNT(self, err) {
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}

function errorOrDestroy(stream, err) {
  // We have tests that rely on errors being emitted
  // in the same tick, so changing this is semver major.
  // For now when you opt-in to autoDestroy we allow
  // the error to be emitted nextTick. In a future
  // semver major update we should change the default to this.
  var rState = stream._readableState;
  var wState = stream._writableState;
  if (rState && rState.autoDestroy || wState && wState.autoDestroy) stream.destroy(err);else stream.emit('error', err);
}

var destroy_1 = {
  destroy: destroy,
  undestroy: undestroy,
  errorOrDestroy: errorOrDestroy
};

function _inheritsLoose(subClass, superClass) { subClass.prototype = Object.create(superClass.prototype); subClass.prototype.constructor = subClass; subClass.__proto__ = superClass; }

var codes = {};

function createErrorType(code, message, Base) {
  if (!Base) {
    Base = Error;
  }

  function getMessage(arg1, arg2, arg3) {
    if (typeof message === 'string') {
      return message;
    } else {
      return message(arg1, arg2, arg3);
    }
  }

  var NodeError =
  /*#__PURE__*/
  function (_Base) {
    _inheritsLoose(NodeError, _Base);

    function NodeError(arg1, arg2, arg3) {
      return _Base.call(this, getMessage(arg1, arg2, arg3)) || this;
    }

    return NodeError;
  }(Base);

  NodeError.prototype.name = Base.name;
  NodeError.prototype.code = code;
  codes[code] = NodeError;
} // https://github.com/nodejs/node/blob/v10.8.0/lib/internal/errors.js


function oneOf(expected, thing) {
  if (Array.isArray(expected)) {
    var len = expected.length;
    expected = expected.map(function (i) {
      return String(i);
    });

    if (len > 2) {
      return "one of ".concat(thing, " ").concat(expected.slice(0, len - 1).join(', '), ", or ") + expected[len - 1];
    } else if (len === 2) {
      return "one of ".concat(thing, " ").concat(expected[0], " or ").concat(expected[1]);
    } else {
      return "of ".concat(thing, " ").concat(expected[0]);
    }
  } else {
    return "of ".concat(thing, " ").concat(String(expected));
  }
} // https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/startsWith


function startsWith(str, search, pos) {
  return str.substr(!pos || pos < 0 ? 0 : +pos, search.length) === search;
} // https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/endsWith


function endsWith(str, search, this_len) {
  if (this_len === undefined || this_len > str.length) {
    this_len = str.length;
  }

  return str.substring(this_len - search.length, this_len) === search;
} // https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/includes


function includes(str, search, start) {
  if (typeof start !== 'number') {
    start = 0;
  }

  if (start + search.length > str.length) {
    return false;
  } else {
    return str.indexOf(search, start) !== -1;
  }
}

createErrorType('ERR_INVALID_OPT_VALUE', function (name, value) {
  return 'The value "' + value + '" is invalid for option "' + name + '"';
}, TypeError);
createErrorType('ERR_INVALID_ARG_TYPE', function (name, expected, actual) {
  // determiner: 'must be' or 'must not be'
  var determiner;

  if (typeof expected === 'string' && startsWith(expected, 'not ')) {
    determiner = 'must not be';
    expected = expected.replace(/^not /, '');
  } else {
    determiner = 'must be';
  }

  var msg;

  if (endsWith(name, ' argument')) {
    // For cases like 'first argument'
    msg = "The ".concat(name, " ").concat(determiner, " ").concat(oneOf(expected, 'type'));
  } else {
    var type = includes(name, '.') ? 'property' : 'argument';
    msg = "The \"".concat(name, "\" ").concat(type, " ").concat(determiner, " ").concat(oneOf(expected, 'type'));
  }

  msg += ". Received type ".concat(typeof actual);
  return msg;
}, TypeError);
createErrorType('ERR_STREAM_PUSH_AFTER_EOF', 'stream.push() after EOF');
createErrorType('ERR_METHOD_NOT_IMPLEMENTED', function (name) {
  return 'The ' + name + ' method is not implemented';
});
createErrorType('ERR_STREAM_PREMATURE_CLOSE', 'Premature close');
createErrorType('ERR_STREAM_DESTROYED', function (name) {
  return 'Cannot call ' + name + ' after a stream was destroyed';
});
createErrorType('ERR_MULTIPLE_CALLBACK', 'Callback called multiple times');
createErrorType('ERR_STREAM_CANNOT_PIPE', 'Cannot pipe, not readable');
createErrorType('ERR_STREAM_WRITE_AFTER_END', 'write after end');
createErrorType('ERR_STREAM_NULL_VALUES', 'May not write null values to stream', TypeError);
createErrorType('ERR_UNKNOWN_ENCODING', function (arg) {
  return 'Unknown encoding: ' + arg;
}, TypeError);
createErrorType('ERR_STREAM_UNSHIFT_AFTER_END_EVENT', 'stream.unshift() after end event');
var codes_1 = codes;

var errorsBrowser = {
	codes: codes_1
};

var ERR_INVALID_OPT_VALUE = errorsBrowser.codes.ERR_INVALID_OPT_VALUE;

function highWaterMarkFrom(options, isDuplex, duplexKey) {
  return options.highWaterMark != null ? options.highWaterMark : isDuplex ? options[duplexKey] : null;
}

function getHighWaterMark(state, options, duplexKey, isDuplex) {
  var hwm = highWaterMarkFrom(options, isDuplex, duplexKey);

  if (hwm != null) {
    if (!(isFinite(hwm) && Math.floor(hwm) === hwm) || hwm < 0) {
      var name = isDuplex ? duplexKey : 'highWaterMark';
      throw new ERR_INVALID_OPT_VALUE(name, hwm);
    }

    return Math.floor(hwm);
  } // Default value


  return state.objectMode ? 16 : 16 * 1024;
}

var state = {
  getHighWaterMark: getHighWaterMark
};

/**
 * Module exports.
 */

var browser = deprecate;

/**
 * Mark that a method should not be used.
 * Returns a modified function which warns once by default.
 *
 * If `localStorage.noDeprecation = true` is set, then it is a no-op.
 *
 * If `localStorage.throwDeprecation = true` is set, then deprecated functions
 * will throw an Error when invoked.
 *
 * If `localStorage.traceDeprecation = true` is set, then deprecated functions
 * will invoke `console.trace()` instead of `console.error()`.
 *
 * @param {Function} fn - the function to deprecate
 * @param {String} msg - the string to print to the console when `fn` is invoked
 * @returns {Function} a new "deprecated" version of `fn`
 * @api public
 */

function deprecate (fn, msg) {
  if (config('noDeprecation')) {
    return fn;
  }

  var warned = false;
  function deprecated() {
    if (!warned) {
      if (config('throwDeprecation')) {
        throw new Error(msg);
      } else if (config('traceDeprecation')) {
        console.trace(msg);
      } else {
        console.warn(msg);
      }
      warned = true;
    }
    return fn.apply(this, arguments);
  }

  return deprecated;
}

/**
 * Checks `localStorage` for boolean values for the given `name`.
 *
 * @param {String} name
 * @returns {Boolean}
 * @api private
 */

function config (name) {
  // accessing global.localStorage can trigger a DOMException in sandboxed iframes
  try {
    if (!commonjsGlobal.localStorage) return false;
  } catch (_) {
    return false;
  }
  var val = commonjsGlobal.localStorage[name];
  if (null == val) return false;
  return String(val).toLowerCase() === 'true';
}

var _stream_writable = Writable;
// there will be only 2 of these for each stream


function CorkedRequest(state) {
  var _this = this;

  this.next = null;
  this.entry = null;

  this.finish = function () {
    onCorkedFinish(_this, state);
  };
}
/* </replacement> */

/*<replacement>*/


var Duplex;
/*</replacement>*/

Writable.WritableState = WritableState;
/*<replacement>*/

var internalUtil = {
  deprecate: browser
};
/*</replacement>*/

/*<replacement>*/


/*</replacement>*/


var Buffer$2 = buffer.Buffer;

var OurUint8Array = commonjsGlobal.Uint8Array || function () {};

function _uint8ArrayToBuffer(chunk) {
  return Buffer$2.from(chunk);
}

function _isUint8Array(obj) {
  return Buffer$2.isBuffer(obj) || obj instanceof OurUint8Array;
}



var getHighWaterMark$1 = state.getHighWaterMark;

var _require$codes = errorsBrowser.codes,
    ERR_INVALID_ARG_TYPE = _require$codes.ERR_INVALID_ARG_TYPE,
    ERR_METHOD_NOT_IMPLEMENTED = _require$codes.ERR_METHOD_NOT_IMPLEMENTED,
    ERR_MULTIPLE_CALLBACK = _require$codes.ERR_MULTIPLE_CALLBACK,
    ERR_STREAM_CANNOT_PIPE = _require$codes.ERR_STREAM_CANNOT_PIPE,
    ERR_STREAM_DESTROYED = _require$codes.ERR_STREAM_DESTROYED,
    ERR_STREAM_NULL_VALUES = _require$codes.ERR_STREAM_NULL_VALUES,
    ERR_STREAM_WRITE_AFTER_END = _require$codes.ERR_STREAM_WRITE_AFTER_END,
    ERR_UNKNOWN_ENCODING = _require$codes.ERR_UNKNOWN_ENCODING;

var errorOrDestroy$1 = destroy_1.errorOrDestroy;

inherits_browser(Writable, streamBrowser);

function nop() {}

function WritableState(options, stream, isDuplex) {
  Duplex = Duplex || _stream_duplex;
  options = options || {}; // Duplex streams are both readable and writable, but share
  // the same options object.
  // However, some cases require setting options to different
  // values for the readable and the writable sides of the duplex stream,
  // e.g. options.readableObjectMode vs. options.writableObjectMode, etc.

  if (typeof isDuplex !== 'boolean') isDuplex = stream instanceof Duplex; // object stream flag to indicate whether or not this stream
  // contains buffers or objects.

  this.objectMode = !!options.objectMode;
  if (isDuplex) this.objectMode = this.objectMode || !!options.writableObjectMode; // the point at which write() starts returning false
  // Note: 0 is a valid value, means that we always return false if
  // the entire buffer is not flushed immediately on write()

  this.highWaterMark = getHighWaterMark$1(this, options, 'writableHighWaterMark', isDuplex); // if _final has been called

  this.finalCalled = false; // drain event flag.

  this.needDrain = false; // at the start of calling end()

  this.ending = false; // when end() has been called, and returned

  this.ended = false; // when 'finish' is emitted

  this.finished = false; // has it been destroyed

  this.destroyed = false; // should we decode strings into buffers before passing to _write?
  // this is here so that some node-core streams can optimize string
  // handling at a lower level.

  var noDecode = options.decodeStrings === false;
  this.decodeStrings = !noDecode; // Crypto is kind of old and crusty.  Historically, its default string
  // encoding is 'binary' so we have to make this configurable.
  // Everything else in the universe uses 'utf8', though.

  this.defaultEncoding = options.defaultEncoding || 'utf8'; // not an actual buffer we keep track of, but a measurement
  // of how much we're waiting to get pushed to some underlying
  // socket or file.

  this.length = 0; // a flag to see when we're in the middle of a write.

  this.writing = false; // when true all writes will be buffered until .uncork() call

  this.corked = 0; // a flag to be able to tell if the onwrite cb is called immediately,
  // or on a later tick.  We set this to true at first, because any
  // actions that shouldn't happen until "later" should generally also
  // not happen before the first write call.

  this.sync = true; // a flag to know if we're processing previously buffered items, which
  // may call the _write() callback in the same tick, so that we don't
  // end up in an overlapped onwrite situation.

  this.bufferProcessing = false; // the callback that's passed to _write(chunk,cb)

  this.onwrite = function (er) {
    onwrite(stream, er);
  }; // the callback that the user supplies to write(chunk,encoding,cb)


  this.writecb = null; // the amount that is being written when _write is called.

  this.writelen = 0;
  this.bufferedRequest = null;
  this.lastBufferedRequest = null; // number of pending user-supplied write callbacks
  // this must be 0 before 'finish' can be emitted

  this.pendingcb = 0; // emit prefinish if the only thing we're waiting for is _write cbs
  // This is relevant for synchronous Transform streams

  this.prefinished = false; // True if the error was already emitted and should not be thrown again

  this.errorEmitted = false; // Should close be emitted on destroy. Defaults to true.

  this.emitClose = options.emitClose !== false; // Should .destroy() be called after 'finish' (and potentially 'end')

  this.autoDestroy = !!options.autoDestroy; // count buffered requests

  this.bufferedRequestCount = 0; // allocate the first CorkedRequest, there is always
  // one allocated and free to use, and we maintain at most two

  this.corkedRequestsFree = new CorkedRequest(this);
}

WritableState.prototype.getBuffer = function getBuffer() {
  var current = this.bufferedRequest;
  var out = [];

  while (current) {
    out.push(current);
    current = current.next;
  }

  return out;
};

(function () {
  try {
    Object.defineProperty(WritableState.prototype, 'buffer', {
      get: internalUtil.deprecate(function writableStateBufferGetter() {
        return this.getBuffer();
      }, '_writableState.buffer is deprecated. Use _writableState.getBuffer ' + 'instead.', 'DEP0003')
    });
  } catch (_) {}
})(); // Test _writableState for inheritance to account for Duplex streams,
// whose prototype chain only points to Readable.


var realHasInstance;

if (typeof Symbol === 'function' && Symbol.hasInstance && typeof Function.prototype[Symbol.hasInstance] === 'function') {
  realHasInstance = Function.prototype[Symbol.hasInstance];
  Object.defineProperty(Writable, Symbol.hasInstance, {
    value: function value(object) {
      if (realHasInstance.call(this, object)) return true;
      if (this !== Writable) return false;
      return object && object._writableState instanceof WritableState;
    }
  });
} else {
  realHasInstance = function realHasInstance(object) {
    return object instanceof this;
  };
}

function Writable(options) {
  Duplex = Duplex || _stream_duplex; // Writable ctor is applied to Duplexes, too.
  // `realHasInstance` is necessary because using plain `instanceof`
  // would return false, as no `_writableState` property is attached.
  // Trying to use the custom `instanceof` for Writable here will also break the
  // Node.js LazyTransform implementation, which has a non-trivial getter for
  // `_writableState` that would lead to infinite recursion.
  // Checking for a Stream.Duplex instance is faster here instead of inside
  // the WritableState constructor, at least with V8 6.5

  var isDuplex = this instanceof Duplex;
  if (!isDuplex && !realHasInstance.call(Writable, this)) return new Writable(options);
  this._writableState = new WritableState(options, this, isDuplex); // legacy.

  this.writable = true;

  if (options) {
    if (typeof options.write === 'function') this._write = options.write;
    if (typeof options.writev === 'function') this._writev = options.writev;
    if (typeof options.destroy === 'function') this._destroy = options.destroy;
    if (typeof options.final === 'function') this._final = options.final;
  }

  streamBrowser.call(this);
} // Otherwise people can pipe Writable streams, which is just wrong.


Writable.prototype.pipe = function () {
  errorOrDestroy$1(this, new ERR_STREAM_CANNOT_PIPE());
};

function writeAfterEnd(stream, cb) {
  var er = new ERR_STREAM_WRITE_AFTER_END(); // TODO: defer error events consistently everywhere, not just the cb

  errorOrDestroy$1(stream, er);
  process.nextTick(cb, er);
} // Checks that a user-supplied chunk is valid, especially for the particular
// mode the stream is in. Currently this means that `null` is never accepted
// and undefined/non-string values are only allowed in object mode.


function validChunk(stream, state, chunk, cb) {
  var er;

  if (chunk === null) {
    er = new ERR_STREAM_NULL_VALUES();
  } else if (typeof chunk !== 'string' && !state.objectMode) {
    er = new ERR_INVALID_ARG_TYPE('chunk', ['string', 'Buffer'], chunk);
  }

  if (er) {
    errorOrDestroy$1(stream, er);
    process.nextTick(cb, er);
    return false;
  }

  return true;
}

Writable.prototype.write = function (chunk, encoding, cb) {
  var state = this._writableState;
  var ret = false;

  var isBuf = !state.objectMode && _isUint8Array(chunk);

  if (isBuf && !Buffer$2.isBuffer(chunk)) {
    chunk = _uint8ArrayToBuffer(chunk);
  }

  if (typeof encoding === 'function') {
    cb = encoding;
    encoding = null;
  }

  if (isBuf) encoding = 'buffer';else if (!encoding) encoding = state.defaultEncoding;
  if (typeof cb !== 'function') cb = nop;
  if (state.ending) writeAfterEnd(this, cb);else if (isBuf || validChunk(this, state, chunk, cb)) {
    state.pendingcb++;
    ret = writeOrBuffer(this, state, isBuf, chunk, encoding, cb);
  }
  return ret;
};

Writable.prototype.cork = function () {
  this._writableState.corked++;
};

Writable.prototype.uncork = function () {
  var state = this._writableState;

  if (state.corked) {
    state.corked--;
    if (!state.writing && !state.corked && !state.bufferProcessing && state.bufferedRequest) clearBuffer(this, state);
  }
};

Writable.prototype.setDefaultEncoding = function setDefaultEncoding(encoding) {
  // node::ParseEncoding() requires lower case.
  if (typeof encoding === 'string') encoding = encoding.toLowerCase();
  if (!(['hex', 'utf8', 'utf-8', 'ascii', 'binary', 'base64', 'ucs2', 'ucs-2', 'utf16le', 'utf-16le', 'raw'].indexOf((encoding + '').toLowerCase()) > -1)) throw new ERR_UNKNOWN_ENCODING(encoding);
  this._writableState.defaultEncoding = encoding;
  return this;
};

Object.defineProperty(Writable.prototype, 'writableBuffer', {
  // making it explicit this property is not enumerable
  // because otherwise some prototype manipulation in
  // userland will fail
  enumerable: false,
  get: function get() {
    return this._writableState && this._writableState.getBuffer();
  }
});

function decodeChunk(state, chunk, encoding) {
  if (!state.objectMode && state.decodeStrings !== false && typeof chunk === 'string') {
    chunk = Buffer$2.from(chunk, encoding);
  }

  return chunk;
}

Object.defineProperty(Writable.prototype, 'writableHighWaterMark', {
  // making it explicit this property is not enumerable
  // because otherwise some prototype manipulation in
  // userland will fail
  enumerable: false,
  get: function get() {
    return this._writableState.highWaterMark;
  }
}); // if we're already writing something, then just put this
// in the queue, and wait our turn.  Otherwise, call _write
// If we return false, then we need a drain event, so set that flag.

function writeOrBuffer(stream, state, isBuf, chunk, encoding, cb) {
  if (!isBuf) {
    var newChunk = decodeChunk(state, chunk, encoding);

    if (chunk !== newChunk) {
      isBuf = true;
      encoding = 'buffer';
      chunk = newChunk;
    }
  }

  var len = state.objectMode ? 1 : chunk.length;
  state.length += len;
  var ret = state.length < state.highWaterMark; // we must ensure that previous needDrain will not be reset to false.

  if (!ret) state.needDrain = true;

  if (state.writing || state.corked) {
    var last = state.lastBufferedRequest;
    state.lastBufferedRequest = {
      chunk: chunk,
      encoding: encoding,
      isBuf: isBuf,
      callback: cb,
      next: null
    };

    if (last) {
      last.next = state.lastBufferedRequest;
    } else {
      state.bufferedRequest = state.lastBufferedRequest;
    }

    state.bufferedRequestCount += 1;
  } else {
    doWrite(stream, state, false, len, chunk, encoding, cb);
  }

  return ret;
}

function doWrite(stream, state, writev, len, chunk, encoding, cb) {
  state.writelen = len;
  state.writecb = cb;
  state.writing = true;
  state.sync = true;
  if (state.destroyed) state.onwrite(new ERR_STREAM_DESTROYED('write'));else if (writev) stream._writev(chunk, state.onwrite);else stream._write(chunk, encoding, state.onwrite);
  state.sync = false;
}

function onwriteError(stream, state, sync, er, cb) {
  --state.pendingcb;

  if (sync) {
    // defer the callback if we are being called synchronously
    // to avoid piling up things on the stack
    process.nextTick(cb, er); // this can emit finish, and it will always happen
    // after error

    process.nextTick(finishMaybe, stream, state);
    stream._writableState.errorEmitted = true;
    errorOrDestroy$1(stream, er);
  } else {
    // the caller expect this to happen before if
    // it is async
    cb(er);
    stream._writableState.errorEmitted = true;
    errorOrDestroy$1(stream, er); // this can emit finish, but finish must
    // always follow error

    finishMaybe(stream, state);
  }
}

function onwriteStateUpdate(state) {
  state.writing = false;
  state.writecb = null;
  state.length -= state.writelen;
  state.writelen = 0;
}

function onwrite(stream, er) {
  var state = stream._writableState;
  var sync = state.sync;
  var cb = state.writecb;
  if (typeof cb !== 'function') throw new ERR_MULTIPLE_CALLBACK();
  onwriteStateUpdate(state);
  if (er) onwriteError(stream, state, sync, er, cb);else {
    // Check if we're actually ready to finish, but don't emit yet
    var finished = needFinish(state) || stream.destroyed;

    if (!finished && !state.corked && !state.bufferProcessing && state.bufferedRequest) {
      clearBuffer(stream, state);
    }

    if (sync) {
      process.nextTick(afterWrite, stream, state, finished, cb);
    } else {
      afterWrite(stream, state, finished, cb);
    }
  }
}

function afterWrite(stream, state, finished, cb) {
  if (!finished) onwriteDrain(stream, state);
  state.pendingcb--;
  cb();
  finishMaybe(stream, state);
} // Must force callback to be called on nextTick, so that we don't
// emit 'drain' before the write() consumer gets the 'false' return
// value, and has a chance to attach a 'drain' listener.


function onwriteDrain(stream, state) {
  if (state.length === 0 && state.needDrain) {
    state.needDrain = false;
    stream.emit('drain');
  }
} // if there's something in the buffer waiting, then process it


function clearBuffer(stream, state) {
  state.bufferProcessing = true;
  var entry = state.bufferedRequest;

  if (stream._writev && entry && entry.next) {
    // Fast case, write everything using _writev()
    var l = state.bufferedRequestCount;
    var buffer = new Array(l);
    var holder = state.corkedRequestsFree;
    holder.entry = entry;
    var count = 0;
    var allBuffers = true;

    while (entry) {
      buffer[count] = entry;
      if (!entry.isBuf) allBuffers = false;
      entry = entry.next;
      count += 1;
    }

    buffer.allBuffers = allBuffers;
    doWrite(stream, state, true, state.length, buffer, '', holder.finish); // doWrite is almost always async, defer these to save a bit of time
    // as the hot path ends with doWrite

    state.pendingcb++;
    state.lastBufferedRequest = null;

    if (holder.next) {
      state.corkedRequestsFree = holder.next;
      holder.next = null;
    } else {
      state.corkedRequestsFree = new CorkedRequest(state);
    }

    state.bufferedRequestCount = 0;
  } else {
    // Slow case, write chunks one-by-one
    while (entry) {
      var chunk = entry.chunk;
      var encoding = entry.encoding;
      var cb = entry.callback;
      var len = state.objectMode ? 1 : chunk.length;
      doWrite(stream, state, false, len, chunk, encoding, cb);
      entry = entry.next;
      state.bufferedRequestCount--; // if we didn't call the onwrite immediately, then
      // it means that we need to wait until it does.
      // also, that means that the chunk and cb are currently
      // being processed, so move the buffer counter past them.

      if (state.writing) {
        break;
      }
    }

    if (entry === null) state.lastBufferedRequest = null;
  }

  state.bufferedRequest = entry;
  state.bufferProcessing = false;
}

Writable.prototype._write = function (chunk, encoding, cb) {
  cb(new ERR_METHOD_NOT_IMPLEMENTED('_write()'));
};

Writable.prototype._writev = null;

Writable.prototype.end = function (chunk, encoding, cb) {
  var state = this._writableState;

  if (typeof chunk === 'function') {
    cb = chunk;
    chunk = null;
    encoding = null;
  } else if (typeof encoding === 'function') {
    cb = encoding;
    encoding = null;
  }

  if (chunk !== null && chunk !== undefined) this.write(chunk, encoding); // .end() fully uncorks

  if (state.corked) {
    state.corked = 1;
    this.uncork();
  } // ignore unnecessary end() calls.


  if (!state.ending) endWritable(this, state, cb);
  return this;
};

Object.defineProperty(Writable.prototype, 'writableLength', {
  // making it explicit this property is not enumerable
  // because otherwise some prototype manipulation in
  // userland will fail
  enumerable: false,
  get: function get() {
    return this._writableState.length;
  }
});

function needFinish(state) {
  return state.ending && state.length === 0 && state.bufferedRequest === null && !state.finished && !state.writing;
}

function callFinal(stream, state) {
  stream._final(function (err) {
    state.pendingcb--;

    if (err) {
      errorOrDestroy$1(stream, err);
    }

    state.prefinished = true;
    stream.emit('prefinish');
    finishMaybe(stream, state);
  });
}

function prefinish(stream, state) {
  if (!state.prefinished && !state.finalCalled) {
    if (typeof stream._final === 'function' && !state.destroyed) {
      state.pendingcb++;
      state.finalCalled = true;
      process.nextTick(callFinal, stream, state);
    } else {
      state.prefinished = true;
      stream.emit('prefinish');
    }
  }
}

function finishMaybe(stream, state) {
  var need = needFinish(state);

  if (need) {
    prefinish(stream, state);

    if (state.pendingcb === 0) {
      state.finished = true;
      stream.emit('finish');

      if (state.autoDestroy) {
        // In case of duplex streams we need a way to detect
        // if the readable side is ready for autoDestroy as well
        var rState = stream._readableState;

        if (!rState || rState.autoDestroy && rState.endEmitted) {
          stream.destroy();
        }
      }
    }
  }

  return need;
}

function endWritable(stream, state, cb) {
  state.ending = true;
  finishMaybe(stream, state);

  if (cb) {
    if (state.finished) process.nextTick(cb);else stream.once('finish', cb);
  }

  state.ended = true;
  stream.writable = false;
}

function onCorkedFinish(corkReq, state, err) {
  var entry = corkReq.entry;
  corkReq.entry = null;

  while (entry) {
    var cb = entry.callback;
    state.pendingcb--;
    cb(err);
    entry = entry.next;
  } // reuse the free corkReq.


  state.corkedRequestsFree.next = corkReq;
}

Object.defineProperty(Writable.prototype, 'destroyed', {
  // making it explicit this property is not enumerable
  // because otherwise some prototype manipulation in
  // userland will fail
  enumerable: false,
  get: function get() {
    if (this._writableState === undefined) {
      return false;
    }

    return this._writableState.destroyed;
  },
  set: function set(value) {
    // we ignore the value if the stream
    // has not been initialized yet
    if (!this._writableState) {
      return;
    } // backward compatibility, the user is explicitly
    // managing destroyed


    this._writableState.destroyed = value;
  }
});
Writable.prototype.destroy = destroy_1.destroy;
Writable.prototype._undestroy = destroy_1.undestroy;

Writable.prototype._destroy = function (err, cb) {
  cb(err);
};

/*<replacement>*/

var objectKeys = Object.keys || function (obj) {
  var keys = [];

  for (var key in obj) {
    keys.push(key);
  }

  return keys;
};
/*</replacement>*/


var _stream_duplex = Duplex$1;





inherits_browser(Duplex$1, _stream_readable);

{
  // Allow the keys array to be GC'ed.
  var keys = objectKeys(_stream_writable.prototype);

  for (var v = 0; v < keys.length; v++) {
    var method = keys[v];
    if (!Duplex$1.prototype[method]) Duplex$1.prototype[method] = _stream_writable.prototype[method];
  }
}

function Duplex$1(options) {
  if (!(this instanceof Duplex$1)) return new Duplex$1(options);
  _stream_readable.call(this, options);
  _stream_writable.call(this, options);
  this.allowHalfOpen = true;

  if (options) {
    if (options.readable === false) this.readable = false;
    if (options.writable === false) this.writable = false;

    if (options.allowHalfOpen === false) {
      this.allowHalfOpen = false;
      this.once('end', onend);
    }
  }
}

Object.defineProperty(Duplex$1.prototype, 'writableHighWaterMark', {
  // making it explicit this property is not enumerable
  // because otherwise some prototype manipulation in
  // userland will fail
  enumerable: false,
  get: function get() {
    return this._writableState.highWaterMark;
  }
});
Object.defineProperty(Duplex$1.prototype, 'writableBuffer', {
  // making it explicit this property is not enumerable
  // because otherwise some prototype manipulation in
  // userland will fail
  enumerable: false,
  get: function get() {
    return this._writableState && this._writableState.getBuffer();
  }
});
Object.defineProperty(Duplex$1.prototype, 'writableLength', {
  // making it explicit this property is not enumerable
  // because otherwise some prototype manipulation in
  // userland will fail
  enumerable: false,
  get: function get() {
    return this._writableState.length;
  }
}); // the no-half-open enforcer

function onend() {
  // If the writable side ended, then we're ok.
  if (this._writableState.ended) return; // no more data can be written.
  // But allow more writes to happen in this tick.

  process.nextTick(onEndNT, this);
}

function onEndNT(self) {
  self.end();
}

Object.defineProperty(Duplex$1.prototype, 'destroyed', {
  // making it explicit this property is not enumerable
  // because otherwise some prototype manipulation in
  // userland will fail
  enumerable: false,
  get: function get() {
    if (this._readableState === undefined || this._writableState === undefined) {
      return false;
    }

    return this._readableState.destroyed && this._writableState.destroyed;
  },
  set: function set(value) {
    // we ignore the value if the stream
    // has not been initialized yet
    if (this._readableState === undefined || this._writableState === undefined) {
      return;
    } // backward compatibility, the user is explicitly
    // managing destroyed


    this._readableState.destroyed = value;
    this._writableState.destroyed = value;
  }
});

/*<replacement>*/

var Buffer$3 = safeBuffer.Buffer;
/*</replacement>*/

var isEncoding = Buffer$3.isEncoding || function (encoding) {
  encoding = '' + encoding;
  switch (encoding && encoding.toLowerCase()) {
    case 'hex':case 'utf8':case 'utf-8':case 'ascii':case 'binary':case 'base64':case 'ucs2':case 'ucs-2':case 'utf16le':case 'utf-16le':case 'raw':
      return true;
    default:
      return false;
  }
};

function _normalizeEncoding(enc) {
  if (!enc) return 'utf8';
  var retried;
  while (true) {
    switch (enc) {
      case 'utf8':
      case 'utf-8':
        return 'utf8';
      case 'ucs2':
      case 'ucs-2':
      case 'utf16le':
      case 'utf-16le':
        return 'utf16le';
      case 'latin1':
      case 'binary':
        return 'latin1';
      case 'base64':
      case 'ascii':
      case 'hex':
        return enc;
      default:
        if (retried) return; // undefined
        enc = ('' + enc).toLowerCase();
        retried = true;
    }
  }
}
// Do not cache `Buffer.isEncoding` when checking encoding names as some
// modules monkey-patch it to support additional encodings
function normalizeEncoding(enc) {
  var nenc = _normalizeEncoding(enc);
  if (typeof nenc !== 'string' && (Buffer$3.isEncoding === isEncoding || !isEncoding(enc))) throw new Error('Unknown encoding: ' + enc);
  return nenc || enc;
}

// StringDecoder provides an interface for efficiently splitting a series of
// buffers into a series of JS strings without breaking apart multi-byte
// characters.
var StringDecoder_1 = StringDecoder;
function StringDecoder(encoding) {
  this.encoding = normalizeEncoding(encoding);
  var nb;
  switch (this.encoding) {
    case 'utf16le':
      this.text = utf16Text;
      this.end = utf16End;
      nb = 4;
      break;
    case 'utf8':
      this.fillLast = utf8FillLast;
      nb = 4;
      break;
    case 'base64':
      this.text = base64Text;
      this.end = base64End;
      nb = 3;
      break;
    default:
      this.write = simpleWrite;
      this.end = simpleEnd;
      return;
  }
  this.lastNeed = 0;
  this.lastTotal = 0;
  this.lastChar = Buffer$3.allocUnsafe(nb);
}

StringDecoder.prototype.write = function (buf) {
  if (buf.length === 0) return '';
  var r;
  var i;
  if (this.lastNeed) {
    r = this.fillLast(buf);
    if (r === undefined) return '';
    i = this.lastNeed;
    this.lastNeed = 0;
  } else {
    i = 0;
  }
  if (i < buf.length) return r ? r + this.text(buf, i) : this.text(buf, i);
  return r || '';
};

StringDecoder.prototype.end = utf8End;

// Returns only complete characters in a Buffer
StringDecoder.prototype.text = utf8Text;

// Attempts to complete a partial non-UTF-8 character using bytes from a Buffer
StringDecoder.prototype.fillLast = function (buf) {
  if (this.lastNeed <= buf.length) {
    buf.copy(this.lastChar, this.lastTotal - this.lastNeed, 0, this.lastNeed);
    return this.lastChar.toString(this.encoding, 0, this.lastTotal);
  }
  buf.copy(this.lastChar, this.lastTotal - this.lastNeed, 0, buf.length);
  this.lastNeed -= buf.length;
};

// Checks the type of a UTF-8 byte, whether it's ASCII, a leading byte, or a
// continuation byte. If an invalid byte is detected, -2 is returned.
function utf8CheckByte(byte) {
  if (byte <= 0x7F) return 0;else if (byte >> 5 === 0x06) return 2;else if (byte >> 4 === 0x0E) return 3;else if (byte >> 3 === 0x1E) return 4;
  return byte >> 6 === 0x02 ? -1 : -2;
}

// Checks at most 3 bytes at the end of a Buffer in order to detect an
// incomplete multi-byte UTF-8 character. The total number of bytes (2, 3, or 4)
// needed to complete the UTF-8 character (if applicable) are returned.
function utf8CheckIncomplete(self, buf, i) {
  var j = buf.length - 1;
  if (j < i) return 0;
  var nb = utf8CheckByte(buf[j]);
  if (nb >= 0) {
    if (nb > 0) self.lastNeed = nb - 1;
    return nb;
  }
  if (--j < i || nb === -2) return 0;
  nb = utf8CheckByte(buf[j]);
  if (nb >= 0) {
    if (nb > 0) self.lastNeed = nb - 2;
    return nb;
  }
  if (--j < i || nb === -2) return 0;
  nb = utf8CheckByte(buf[j]);
  if (nb >= 0) {
    if (nb > 0) {
      if (nb === 2) nb = 0;else self.lastNeed = nb - 3;
    }
    return nb;
  }
  return 0;
}

// Validates as many continuation bytes for a multi-byte UTF-8 character as
// needed or are available. If we see a non-continuation byte where we expect
// one, we "replace" the validated continuation bytes we've seen so far with
// a single UTF-8 replacement character ('\ufffd'), to match v8's UTF-8 decoding
// behavior. The continuation byte check is included three times in the case
// where all of the continuation bytes for a character exist in the same buffer.
// It is also done this way as a slight performance increase instead of using a
// loop.
function utf8CheckExtraBytes(self, buf, p) {
  if ((buf[0] & 0xC0) !== 0x80) {
    self.lastNeed = 0;
    return '\ufffd';
  }
  if (self.lastNeed > 1 && buf.length > 1) {
    if ((buf[1] & 0xC0) !== 0x80) {
      self.lastNeed = 1;
      return '\ufffd';
    }
    if (self.lastNeed > 2 && buf.length > 2) {
      if ((buf[2] & 0xC0) !== 0x80) {
        self.lastNeed = 2;
        return '\ufffd';
      }
    }
  }
}

// Attempts to complete a multi-byte UTF-8 character using bytes from a Buffer.
function utf8FillLast(buf) {
  var p = this.lastTotal - this.lastNeed;
  var r = utf8CheckExtraBytes(this, buf);
  if (r !== undefined) return r;
  if (this.lastNeed <= buf.length) {
    buf.copy(this.lastChar, p, 0, this.lastNeed);
    return this.lastChar.toString(this.encoding, 0, this.lastTotal);
  }
  buf.copy(this.lastChar, p, 0, buf.length);
  this.lastNeed -= buf.length;
}

// Returns all complete UT