setup-python/node_modules/prettier/third-party.js

'use strict';

function _interopDefault (ex) { return (ex && (typeof ex === 'object') && 'default' in ex) ? ex['default'] : ex; }

var os = _interopDefault(require('os'));
var path = _interopDefault(require('path'));
var util = _interopDefault(require('util'));
var module$1 = _interopDefault(require('module'));
var fs = _interopDefault(require('fs'));
var stream = _interopDefault(require('stream'));

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;
}

function _toArray(arr) {
  return _arrayWithHoles(arr) || _iterableToArray(arr) || _nonIterableRest();
}

function _arrayWithHoles(arr) {
  if (Array.isArray(arr)) return arr;
}

function _iterableToArray(iter) {
  if (Symbol.iterator in Object(iter) || Object.prototype.toString.call(iter) === "[object Arguments]") return Array.from(iter);
}

function _nonIterableRest() {
  throw new TypeError("Invalid attempt to destructure non-iterable instance");
}

function _toPrimitive(input, hint) {
  if (typeof input !== "object" || input === null) return input;
  var prim = input[Symbol.toPrimitive];

  if (prim !== undefined) {
    var res = prim.call(input, hint || "default");
    if (typeof res !== "object") return res;
    throw new TypeError("@@toPrimitive must return a primitive value.");
  }

  return (hint === "string" ? String : Number)(input);
}

function _toPropertyKey(arg) {
  var key = _toPrimitive(arg, "string");

  return typeof key === "symbol" ? key : String(key);
}

function _addElementPlacement(element, placements, silent) {
  var keys = placements[element.placement];

  if (!silent && keys.indexOf(element.key) !== -1) {
    throw new TypeError("Duplicated element (" + element.key + ")");
  }

  keys.push(element.key);
}

function _fromElementDescriptor(element) {
  var obj = {
    kind: element.kind,
    key: element.key,
    placement: element.placement,
    descriptor: element.descriptor
  };
  var desc = {
    value: "Descriptor",
    configurable: true
  };
  Object.defineProperty(obj, Symbol.toStringTag, desc);
  if (element.kind === "field") obj.initializer = element.initializer;
  return obj;
}

function _toElementDescriptors(elementObjects) {
  if (elementObjects === undefined) return;
  return _toArray(elementObjects).map(function (elementObject) {
    var element = _toElementDescriptor(elementObject);

    _disallowProperty(elementObject, "finisher", "An element descriptor");

    _disallowProperty(elementObject, "extras", "An element descriptor");

    return element;
  });
}

function _toElementDescriptor(elementObject) {
  var kind = String(elementObject.kind);

  if (kind !== "method" && kind !== "field") {
    throw new TypeError('An element descriptor\'s .kind property must be either "method" or' + ' "field", but a decorator created an element descriptor with' + ' .kind "' + kind + '"');
  }

  var key = _toPropertyKey(elementObject.key);

  var placement = String(elementObject.placement);

  if (placement !== "static" && placement !== "prototype" && placement !== "own") {
    throw new TypeError('An element descriptor\'s .placement property must be one of "static",' + ' "prototype" or "own", but a decorator created an element descriptor' + ' with .placement "' + placement + '"');
  }

  var descriptor = elementObject.descriptor;

  _disallowProperty(elementObject, "elements", "An element descriptor");

  var element = {
    kind: kind,
    key: key,
    placement: placement,
    descriptor: Object.assign({}, descriptor)
  };

  if (kind !== "field") {
    _disallowProperty(elementObject, "initializer", "A method descriptor");
  } else {
    _disallowProperty(descriptor, "get", "The property descriptor of a field descriptor");

    _disallowProperty(descriptor, "set", "The property descriptor of a field descriptor");

    _disallowProperty(descriptor, "value", "The property descriptor of a field descriptor");

    element.initializer = elementObject.initializer;
  }

  return element;
}

function _toElementFinisherExtras(elementObject) {
  var element = _toElementDescriptor(elementObject);

  var finisher = _optionalCallableProperty(elementObject, "finisher");

  var extras = _toElementDescriptors(elementObject.extras);

  return {
    element: element,
    finisher: finisher,
    extras: extras
  };
}

function _fromClassDescriptor(elements) {
  var obj = {
    kind: "class",
    elements: elements.map(_fromElementDescriptor)
  };
  var desc = {
    value: "Descriptor",
    configurable: true
  };
  Object.defineProperty(obj, Symbol.toStringTag, desc);
  return obj;
}

function _toClassDescriptor(obj) {
  var kind = String(obj.kind);

  if (kind !== "class") {
    throw new TypeError('A class descriptor\'s .kind property must be "class", but a decorator' + ' created a class descriptor with .kind "' + kind + '"');
  }

  _disallowProperty(obj, "key", "A class descriptor");

  _disallowProperty(obj, "placement", "A class descriptor");

  _disallowProperty(obj, "descriptor", "A class descriptor");

  _disallowProperty(obj, "initializer", "A class descriptor");

  _disallowProperty(obj, "extras", "A class descriptor");

  var finisher = _optionalCallableProperty(obj, "finisher");

  var elements = _toElementDescriptors(obj.elements);

  return {
    elements: elements,
    finisher: finisher
  };
}

function _disallowProperty(obj, name, objectType) {
  if (obj[name] !== undefined) {
    throw new TypeError(objectType + " can't have a ." + name + " property.");
  }
}

function _optionalCallableProperty(obj, name) {
  var value = obj[name];

  if (value !== undefined && typeof value !== "function") {
    throw new TypeError("Expected '" + name + "' to be a function");
  }

  return value;
}

function commonjsRequire () {
	throw new Error('Dynamic requires are not currently supported by rollup-plugin-commonjs');
}



function createCommonjsModule(fn, module) {
	return module = { exports: {} }, fn(module, module.exports), module.exports;
}

var isArrayish = function isArrayish(obj) {
  if (!obj) {
    return false;
  }

  return obj instanceof Array || Array.isArray(obj) || obj.length >= 0 && obj.splice instanceof Function;
};

var errorEx = function errorEx(name, properties) {
  if (!name || name.constructor !== String) {
    properties = name || {};
    name = Error.name;
  }

  var errorExError = function ErrorEXError(message) {
    if (!this) {
      return new ErrorEXError(message);
    }

    message = message instanceof Error ? message.message : message || this.message;
    Error.call(this, message);
    Error.captureStackTrace(this, errorExError);
    this.name = name;
    Object.defineProperty(this, 'message', {
      configurable: true,
      enumerable: false,
      get: function get() {
        var newMessage = message.split(/\r?\n/g);

        for (var key in properties) {
          if (!properties.hasOwnProperty(key)) {
            continue;
          }

          var modifier = properties[key];

          if ('message' in modifier) {
            newMessage = modifier.message(this[key], newMessage) || newMessage;

            if (!isArrayish(newMessage)) {
              newMessage = [newMessage];
            }
          }
        }

        return newMessage.join('\n');
      },
      set: function set(v) {
        message = v;
      }
    });
    var overwrittenStack = null;
    var stackDescriptor = Object.getOwnPropertyDescriptor(this, 'stack');
    var stackGetter = stackDescriptor.get;
    var stackValue = stackDescriptor.value;
    delete stackDescriptor.value;
    delete stackDescriptor.writable;

    stackDescriptor.set = function (newstack) {
      overwrittenStack = newstack;
    };

    stackDescriptor.get = function () {
      var stack = (overwrittenStack || (stackGetter ? stackGetter.call(this) : stackValue)).split(/\r?\n+/g); // starting in Node 7, the stack builder caches the message.
      // just replace it.

      if (!overwrittenStack) {
        stack[0] = this.name + ': ' + this.message;
      }

      var lineCount = 1;

      for (var key in properties) {
        if (!properties.hasOwnProperty(key)) {
          continue;
        }

        var modifier = properties[key];

        if ('line' in modifier) {
          var line = modifier.line(this[key]);

          if (line) {
            stack.splice(lineCount++, 0, '    ' + line);
          }
        }

        if ('stack' in modifier) {
          modifier.stack(this[key], stack);
        }
      }

      return stack.join('\n');
    };

    Object.defineProperty(this, 'stack', stackDescriptor);
  };

  if (Object.setPrototypeOf) {
    Object.setPrototypeOf(errorExError.prototype, Error.prototype);
    Object.setPrototypeOf(errorExError, Error);
  } else {
    util.inherits(errorExError, Error);
  }

  return errorExError;
};

errorEx.append = function (str, def) {
  return {
    message: function message(v, _message) {
      v = v || def;

      if (v) {
        _message[0] += ' ' + str.replace('%s', v.toString());
      }

      return _message;
    }
  };
};

errorEx.line = function (str, def) {
  return {
    line: function line(v) {
      v = v || def;

      if (v) {
        return str.replace('%s', v.toString());
      }

      return null;
    }
  };
};

var errorEx_1 = errorEx;

var jsonParseBetterErrors = parseJson$2;

function parseJson$2(txt, reviver, context) {
  context = context || 20;

  try {
    return JSON.parse(txt, reviver);
  } catch (e) {
    if (typeof txt !== 'string') {
      var isEmptyArray = Array.isArray(txt) && txt.length === 0;
      var errorMessage = 'Cannot parse ' + (isEmptyArray ? 'an empty array' : String(txt));
      throw new TypeError(errorMessage);
    }

    var syntaxErr = e.message.match(/^Unexpected token.*position\s+(\d+)/i);
    var errIdx = syntaxErr ? +syntaxErr[1] : e.message.match(/^Unexpected end of JSON.*/i) ? txt.length - 1 : null;

    if (errIdx != null) {
      var start = errIdx <= context ? 0 : errIdx - context;
      var end = errIdx + context >= txt.length ? txt.length : errIdx + context;
      e.message += ` while parsing near '${start === 0 ? '' : '...'}${txt.slice(start, end)}${end === txt.length ? '' : '...'}'`;
    } else {
      e.message += ` while parsing '${txt.slice(0, context * 2)}'`;
    }

    throw e;
  }
}

var parseJson = createCommonjsModule(function (module) {
  'use strict';

  var JSONError = errorEx_1('JSONError', {
    fileName: errorEx_1.append('in %s')
  });

  module.exports = function (input, reviver, filename) {
    if (typeof reviver === 'string') {
      filename = reviver;
      reviver = null;
    }

    try {
      try {
        return JSON.parse(input, reviver);
      } catch (err) {
        jsonParseBetterErrors(input, reviver);
        throw err;
      }
    } catch (err) {
      err.message = err.message.replace(/\n/g, '');
      var jsonErr = new JSONError(err);

      if (filename) {
        jsonErr.fileName = filename;
      }

      throw jsonErr;
    }
  };
});

function isNothing(subject) {
  return typeof subject === 'undefined' || subject === null;
}

function isObject(subject) {
  return typeof subject === 'object' && subject !== null;
}

function toArray(sequence) {
  if (Array.isArray(sequence)) return sequence;else if (isNothing(sequence)) return [];
  return [sequence];
}

function extend(target, source) {
  var index, length, key, sourceKeys;

  if (source) {
    sourceKeys = Object.keys(source);

    for (index = 0, length = sourceKeys.length; index < length; index += 1) {
      key = sourceKeys[index];
      target[key] = source[key];
    }
  }

  return target;
}

function repeat(string, count) {
  var result = '',
      cycle;

  for (cycle = 0; cycle < count; cycle += 1) {
    result += string;
  }

  return result;
}

function isNegativeZero(number) {
  return number === 0 && Number.NEGATIVE_INFINITY === 1 / number;
}

var isNothing_1 = isNothing;
var isObject_1 = isObject;
var toArray_1 = toArray;
var repeat_1 = repeat;
var isNegativeZero_1 = isNegativeZero;
var extend_1 = extend;
var common = {
  isNothing: isNothing_1,
  isObject: isObject_1,
  toArray: toArray_1,
  repeat: repeat_1,
  isNegativeZero: isNegativeZero_1,
  extend: extend_1
};

// YAML error class. http://stackoverflow.com/questions/8458984
//
function YAMLException$1(reason, mark) {
  // Super constructor
  Error.call(this);
  this.name = 'YAMLException';
  this.reason = reason;
  this.mark = mark;
  this.message = (this.reason || '(unknown reason)') + (this.mark ? ' ' + this.mark.toString() : ''); // Include stack trace in error object

  if (Error.captureStackTrace) {
    // Chrome and NodeJS
    Error.captureStackTrace(this, this.constructor);
  } else {
    // FF, IE 10+ and Safari 6+. Fallback for others
    this.stack = new Error().stack || '';
  }
} // Inherit from Error


YAMLException$1.prototype = Object.create(Error.prototype);
YAMLException$1.prototype.constructor = YAMLException$1;

YAMLException$1.prototype.toString = function toString(compact) {
  var result = this.name + ': ';
  result += this.reason || '(unknown reason)';

  if (!compact && this.mark) {
    result += ' ' + this.mark.toString();
  }

  return result;
};

var exception = YAMLException$1;

function Mark(name, buffer, position, line, column) {
  this.name = name;
  this.buffer = buffer;
  this.position = position;
  this.line = line;
  this.column = column;
}

Mark.prototype.getSnippet = function getSnippet(indent, maxLength) {
  var head, start, tail, end, snippet;
  if (!this.buffer) return null;
  indent = indent || 4;
  maxLength = maxLength || 75;
  head = '';
  start = this.position;

  while (start > 0 && '\x00\r\n\x85\u2028\u2029'.indexOf(this.buffer.charAt(start - 1)) === -1) {
    start -= 1;

    if (this.position - start > maxLength / 2 - 1) {
      head = ' ... ';
      start += 5;
      break;
    }
  }

  tail = '';
  end = this.position;

  while (end < this.buffer.length && '\x00\r\n\x85\u2028\u2029'.indexOf(this.buffer.charAt(end)) === -1) {
    end += 1;

    if (end - this.position > maxLength / 2 - 1) {
      tail = ' ... ';
      end -= 5;
      break;
    }
  }

  snippet = this.buffer.slice(start, end);
  return common.repeat(' ', indent) + head + snippet + tail + '\n' + common.repeat(' ', indent + this.position - start + head.length) + '^';
};

Mark.prototype.toString = function toString(compact) {
  var snippet,
      where = '';

  if (this.name) {
    where += 'in "' + this.name + '" ';
  }

  where += 'at line ' + (this.line + 1) + ', column ' + (this.column + 1);

  if (!compact) {
    snippet = this.getSnippet();

    if (snippet) {
      where += ':\n' + snippet;
    }
  }

  return where;
};

var mark = Mark;

var TYPE_CONSTRUCTOR_OPTIONS = ['kind', 'resolve', 'construct', 'instanceOf', 'predicate', 'represent', 'defaultStyle', 'styleAliases'];
var YAML_NODE_KINDS = ['scalar', 'sequence', 'mapping'];

function compileStyleAliases(map) {
  var result = {};

  if (map !== null) {
    Object.keys(map).forEach(function (style) {
      map[style].forEach(function (alias) {
        result[String(alias)] = style;
      });
    });
  }

  return result;
}

function Type$1(tag, options) {
  options = options || {};
  Object.keys(options).forEach(function (name) {
    if (TYPE_CONSTRUCTOR_OPTIONS.indexOf(name) === -1) {
      throw new exception('Unknown option "' + name + '" is met in definition of "' + tag + '" YAML type.');
    }
  }); // TODO: Add tag format check.

  this.tag = tag;
  this.kind = options['kind'] || null;

  this.resolve = options['resolve'] || function () {
    return true;
  };

  this.construct = options['construct'] || function (data) {
    return data;
  };

  this.instanceOf = options['instanceOf'] || null;
  this.predicate = options['predicate'] || null;
  this.represent = options['represent'] || null;
  this.defaultStyle = options['defaultStyle'] || null;
  this.styleAliases = compileStyleAliases(options['styleAliases'] || null);

  if (YAML_NODE_KINDS.indexOf(this.kind) === -1) {
    throw new exception('Unknown kind "' + this.kind + '" is specified for "' + tag + '" YAML type.');
  }
}

var type = Type$1;

/*eslint-disable max-len*/


function compileList(schema, name, result) {
  var exclude = [];
  schema.include.forEach(function (includedSchema) {
    result = compileList(includedSchema, name, result);
  });
  schema[name].forEach(function (currentType) {
    result.forEach(function (previousType, previousIndex) {
      if (previousType.tag === currentType.tag && previousType.kind === currentType.kind) {
        exclude.push(previousIndex);
      }
    });
    result.push(currentType);
  });
  return result.filter(function (type$$1, index) {
    return exclude.indexOf(index) === -1;
  });
}

function compileMap()
/* lists... */
{
  var result = {
    scalar: {},
    sequence: {},
    mapping: {},
    fallback: {}
  },
      index,
      length;

  function collectType(type$$1) {
    result[type$$1.kind][type$$1.tag] = result['fallback'][type$$1.tag] = type$$1;
  }

  for (index = 0, length = arguments.length; index < length; index += 1) {
    arguments[index].forEach(collectType);
  }

  return result;
}

function Schema$1(definition) {
  this.include = definition.include || [];
  this.implicit = definition.implicit || [];
  this.explicit = definition.explicit || [];
  this.implicit.forEach(function (type$$1) {
    if (type$$1.loadKind && type$$1.loadKind !== 'scalar') {
      throw new exception('There is a non-scalar type in the implicit list of a schema. Implicit resolving of such types is not supported.');
    }
  });
  this.compiledImplicit = compileList(this, 'implicit', []);
  this.compiledExplicit = compileList(this, 'explicit', []);
  this.compiledTypeMap = compileMap(this.compiledImplicit, this.compiledExplicit);
}

Schema$1.DEFAULT = null;

Schema$1.create = function createSchema() {
  var schemas, types;

  switch (arguments.length) {
    case 1:
      schemas = Schema$1.DEFAULT;
      types = arguments[0];
      break;

    case 2:
      schemas = arguments[0];
      types = arguments[1];
      break;

    default:
      throw new exception('Wrong number of arguments for Schema.create function');
  }

  schemas = common.toArray(schemas);
  types = common.toArray(types);

  if (!schemas.every(function (schema) {
    return schema instanceof Schema$1;
  })) {
    throw new exception('Specified list of super schemas (or a single Schema object) contains a non-Schema object.');
  }

  if (!types.every(function (type$$1) {
    return type$$1 instanceof type;
  })) {
    throw new exception('Specified list of YAML types (or a single Type object) contains a non-Type object.');
  }

  return new Schema$1({
    include: schemas,
    explicit: types
  });
};

var schema = Schema$1;

var str = new type('tag:yaml.org,2002:str', {
  kind: 'scalar',
  construct: function construct(data) {
    return data !== null ? data : '';
  }
});

var seq = new type('tag:yaml.org,2002:seq', {
  kind: 'sequence',
  construct: function construct(data) {
    return data !== null ? data : [];
  }
});

var map = new type('tag:yaml.org,2002:map', {
  kind: 'mapping',
  construct: function construct(data) {
    return data !== null ? data : {};
  }
});

var failsafe = new schema({
  explicit: [str, seq, map]
});

function resolveYamlNull(data) {
  if (data === null) return true;
  var max = data.length;
  return max === 1 && data === '~' || max === 4 && (data === 'null' || data === 'Null' || data === 'NULL');
}

function constructYamlNull() {
  return null;
}

function isNull(object) {
  return object === null;
}

var _null = new type('tag:yaml.org,2002:null', {
  kind: 'scalar',
  resolve: resolveYamlNull,
  construct: constructYamlNull,
  predicate: isNull,
  represent: {
    canonical: function canonical() {
      return '~';
    },
    lowercase: function lowercase() {
      return 'null';
    },
    uppercase: function uppercase() {
      return 'NULL';
    },
    camelcase: function camelcase() {
      return 'Null';
    }
  },
  defaultStyle: 'lowercase'
});

function resolveYamlBoolean(data) {
  if (data === null) return false;
  var max = data.length;
  return max === 4 && (data === 'true' || data === 'True' || data === 'TRUE') || max === 5 && (data === 'false' || data === 'False' || data === 'FALSE');
}

function constructYamlBoolean(data) {
  return data === 'true' || data === 'True' || data === 'TRUE';
}

function isBoolean(object) {
  return Object.prototype.toString.call(object) === '[object Boolean]';
}

var bool = new type('tag:yaml.org,2002:bool', {
  kind: 'scalar',
  resolve: resolveYamlBoolean,
  construct: constructYamlBoolean,
  predicate: isBoolean,
  represent: {
    lowercase: function lowercase(object) {
      return object ? 'true' : 'false';
    },
    uppercase: function uppercase(object) {
      return object ? 'TRUE' : 'FALSE';
    },
    camelcase: function camelcase(object) {
      return object ? 'True' : 'False';
    }
  },
  defaultStyle: 'lowercase'
});

function isHexCode(c) {
  return 0x30
  /* 0 */
  <= c && c <= 0x39
  /* 9 */
  || 0x41
  /* A */
  <= c && c <= 0x46
  /* F */
  || 0x61
  /* a */
  <= c && c <= 0x66
  /* f */
  ;
}

function isOctCode(c) {
  return 0x30
  /* 0 */
  <= c && c <= 0x37
  /* 7 */
  ;
}

function isDecCode(c) {
  return 0x30
  /* 0 */
  <= c && c <= 0x39
  /* 9 */
  ;
}

function resolveYamlInteger(data) {
  if (data === null) return false;
  var max = data.length,
      index = 0,
      hasDigits = false,
      ch;
  if (!max) return false;
  ch = data[index]; // sign

  if (ch === '-' || ch === '+') {
    ch = data[++index];
  }

  if (ch === '0') {
    // 0
    if (index + 1 === max) return true;
    ch = data[++index]; // base 2, base 8, base 16

    if (ch === 'b') {
      // base 2
      index++;

      for (; index < max; index++) {
        ch = data[index];
        if (ch === '_') continue;
        if (ch !== '0' && ch !== '1') return false;
        hasDigits = true;
      }

      return hasDigits && ch !== '_';
    }

    if (ch === 'x') {
      // base 16
      index++;

      for (; index < max; index++) {
        ch = data[index];
        if (ch === '_') continue;
        if (!isHexCode(data.charCodeAt(index))) return false;
        hasDigits = true;
      }

      return hasDigits && ch !== '_';
    } // base 8


    for (; index < max; index++) {
      ch = data[index];
      if (ch === '_') continue;
      if (!isOctCode(data.charCodeAt(index))) return false;
      hasDigits = true;
    }

    return hasDigits && ch !== '_';
  } // base 10 (except 0) or base 60
  // value should not start with `_`;


  if (ch === '_') return false;

  for (; index < max; index++) {
    ch = data[index];
    if (ch === '_') continue;
    if (ch === ':') break;

    if (!isDecCode(data.charCodeAt(index))) {
      return false;
    }

    hasDigits = true;
  } // Should have digits and should not end with `_`


  if (!hasDigits || ch === '_') return false; // if !base60 - done;

  if (ch !== ':') return true; // base60 almost not used, no needs to optimize

  return /^(:[0-5]?[0-9])+$/.test(data.slice(index));
}

function constructYamlInteger(data) {
  var value = data,
      sign = 1,
      ch,
      base,
      digits = [];

  if (value.indexOf('_') !== -1) {
    value = value.replace(/_/g, '');
  }

  ch = value[0];

  if (ch === '-' || ch === '+') {
    if (ch === '-') sign = -1;
    value = value.slice(1);
    ch = value[0];
  }

  if (value === '0') return 0;

  if (ch === '0') {
    if (value[1] === 'b') return sign * parseInt(value.slice(2), 2);
    if (value[1] === 'x') return sign * parseInt(value, 16);
    return sign * parseInt(value, 8);
  }

  if (value.indexOf(':') !== -1) {
    value.split(':').forEach(function (v) {
      digits.unshift(parseInt(v, 10));
    });
    value = 0;
    base = 1;
    digits.forEach(function (d) {
      value += d * base;
      base *= 60;
    });
    return sign * value;
  }

  return sign * parseInt(value, 10);
}

function isInteger(object) {
  return Object.prototype.toString.call(object) === '[object Number]' && object % 1 === 0 && !common.isNegativeZero(object);
}

var int_1 = new type('tag:yaml.org,2002:int', {
  kind: 'scalar',
  resolve: resolveYamlInteger,
  construct: constructYamlInteger,
  predicate: isInteger,
  represent: {
    binary: function binary(obj) {
      return obj >= 0 ? '0b' + obj.toString(2) : '-0b' + obj.toString(2).slice(1);
    },
    octal: function octal(obj) {
      return obj >= 0 ? '0' + obj.toString(8) : '-0' + obj.toString(8).slice(1);
    },
    decimal: function decimal(obj) {
      return obj.toString(10);
    },

    /* eslint-disable max-len */
    hexadecimal: function hexadecimal(obj) {
      return obj >= 0 ? '0x' + obj.toString(16).toUpperCase() : '-0x' + obj.toString(16).toUpperCase().slice(1);
    }
  },
  defaultStyle: 'decimal',
  styleAliases: {
    binary: [2, 'bin'],
    octal: [8, 'oct'],
    decimal: [10, 'dec'],
    hexadecimal: [16, 'hex']
  }
});

var YAML_FLOAT_PATTERN = new RegExp( // 2.5e4, 2.5 and integers
'^(?:[-+]?(?:0|[1-9][0-9_]*)(?:\\.[0-9_]*)?(?:[eE][-+]?[0-9]+)?' + // .2e4, .2
// special case, seems not from spec
'|\\.[0-9_]+(?:[eE][-+]?[0-9]+)?' + // 20:59
'|[-+]?[0-9][0-9_]*(?::[0-5]?[0-9])+\\.[0-9_]*' + // .inf
'|[-+]?\\.(?:inf|Inf|INF)' + // .nan
'|\\.(?:nan|NaN|NAN))$');

function resolveYamlFloat(data) {
  if (data === null) return false;

  if (!YAML_FLOAT_PATTERN.test(data) || // Quick hack to not allow integers end with `_`
  // Probably should update regexp & check speed
  data[data.length - 1] === '_') {
    return false;
  }

  return true;
}

function constructYamlFloat(data) {
  var value, sign, base, digits;
  value = data.replace(/_/g, '').toLowerCase();
  sign = value[0] === '-' ? -1 : 1;
  digits = [];

  if ('+-'.indexOf(value[0]) >= 0) {
    value = value.slice(1);
  }

  if (value === '.inf') {
    return sign === 1 ? Number.POSITIVE_INFINITY : Number.NEGATIVE_INFINITY;
  } else if (value === '.nan') {
    return NaN;
  } else if (value.indexOf(':') >= 0) {
    value.split(':').forEach(function (v) {
      digits.unshift(parseFloat(v, 10));
    });
    value = 0.0;
    base = 1;
    digits.forEach(function (d) {
      value += d * base;
      base *= 60;
    });
    return sign * value;
  }

  return sign * parseFloat(value, 10);
}

var SCIENTIFIC_WITHOUT_DOT = /^[-+]?[0-9]+e/;

function representYamlFloat(object, style) {
  var res;

  if (isNaN(object)) {
    switch (style) {
      case 'lowercase':
        return '.nan';

      case 'uppercase':
        return '.NAN';

      case 'camelcase':
        return '.NaN';
    }
  } else if (Number.POSITIVE_INFINITY === object) {
    switch (style) {
      case 'lowercase':
        return '.inf';

      case 'uppercase':
        return '.INF';

      case 'camelcase':
        return '.Inf';
    }
  } else if (Number.NEGATIVE_INFINITY === object) {
    switch (style) {
      case 'lowercase':
        return '-.inf';

      case 'uppercase':
        return '-.INF';

      case 'camelcase':
        return '-.Inf';
    }
  } else if (common.isNegativeZero(object)) {
    return '-0.0';
  }

  res = object.toString(10); // JS stringifier can build scientific format without dots: 5e-100,
  // while YAML requres dot: 5.e-100. Fix it with simple hack

  return SCIENTIFIC_WITHOUT_DOT.test(res) ? res.replace('e', '.e') : res;
}

function isFloat(object) {
  return Object.prototype.toString.call(object) === '[object Number]' && (object % 1 !== 0 || common.isNegativeZero(object));
}

var float_1 = new type('tag:yaml.org,2002:float', {
  kind: 'scalar',
  resolve: resolveYamlFloat,
  construct: constructYamlFloat,
  predicate: isFloat,
  represent: representYamlFloat,
  defaultStyle: 'lowercase'
});

var json = new schema({
  include: [failsafe],
  implicit: [_null, bool, int_1, float_1]
});

var core = new schema({
  include: [json]
});

var YAML_DATE_REGEXP = new RegExp('^([0-9][0-9][0-9][0-9])' + // [1] year
'-([0-9][0-9])' + // [2] month
'-([0-9][0-9])$'); // [3] day

var YAML_TIMESTAMP_REGEXP = new RegExp('^([0-9][0-9][0-9][0-9])' + // [1] year
'-([0-9][0-9]?)' + // [2] month
'-([0-9][0-9]?)' + // [3] day
'(?:[Tt]|[ \\t]+)' + // ...
'([0-9][0-9]?)' + // [4] hour
':([0-9][0-9])' + // [5] minute
':([0-9][0-9])' + // [6] second
'(?:\\.([0-9]*))?' + // [7] fraction
'(?:[ \\t]*(Z|([-+])([0-9][0-9]?)' + // [8] tz [9] tz_sign [10] tz_hour
'(?::([0-9][0-9]))?))?$'); // [11] tz_minute

function resolveYamlTimestamp(data) {
  if (data === null) return false;
  if (YAML_DATE_REGEXP.exec(data) !== null) return true;
  if (YAML_TIMESTAMP_REGEXP.exec(data) !== null) return true;
  return false;
}

function constructYamlTimestamp(data) {
  var match,
      year,
      month,
      day,
      hour,
      minute,
      second,
      fraction = 0,
      delta = null,
      tz_hour,
      tz_minute,
      date;
  match = YAML_DATE_REGEXP.exec(data);
  if (match === null) match = YAML_TIMESTAMP_REGEXP.exec(data);
  if (match === null) throw new Error('Date resolve error'); // match: [1] year [2] month [3] day

  year = +match[1];
  month = +match[2] - 1; // JS month starts with 0

  day = +match[3];

  if (!match[4]) {
    // no hour
    return new Date(Date.UTC(year, month, day));
  } // match: [4] hour [5] minute [6] second [7] fraction


  hour = +match[4];
  minute = +match[5];
  second = +match[6];

  if (match[7]) {
    fraction = match[7].slice(0, 3);

    while (fraction.length < 3) {
      // milli-seconds
      fraction += '0';
    }

    fraction = +fraction;
  } // match: [8] tz [9] tz_sign [10] tz_hour [11] tz_minute


  if (match[9]) {
    tz_hour = +match[10];
    tz_minute = +(match[11] || 0);
    delta = (tz_hour * 60 + tz_minute) * 60000; // delta in mili-seconds

    if (match[9] === '-') delta = -delta;
  }

  date = new Date(Date.UTC(year, month, day, hour, minute, second, fraction));
  if (delta) date.setTime(date.getTime() - delta);
  return date;
}

function representYamlTimestamp(object
/*, style*/
) {
  return object.toISOString();
}

var timestamp = new type('tag:yaml.org,2002:timestamp', {
  kind: 'scalar',
  resolve: resolveYamlTimestamp,
  construct: constructYamlTimestamp,
  instanceOf: Date,
  represent: representYamlTimestamp
});

function resolveYamlMerge(data) {
  return data === '<<' || data === null;
}

var merge = new type('tag:yaml.org,2002:merge', {
  kind: 'scalar',
  resolve: resolveYamlMerge
});

/*eslint-disable no-bitwise*/


var NodeBuffer;

try {
  // A trick for browserified version, to not include `Buffer` shim
  var _require = commonjsRequire;
  NodeBuffer = _require('buffer').Buffer;
} catch (__) {} // [ 64, 65, 66 ] -> [ padding, CR, LF ]


var BASE64_MAP = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=\n\r';

function resolveYamlBinary(data) {
  if (data === null) return false;
  var code,
      idx,
      bitlen = 0,
      max = data.length,
      map = BASE64_MAP; // Convert one by one.

  for (idx = 0; idx < max; idx++) {
    code = map.indexOf(data.charAt(idx)); // Skip CR/LF

    if (code > 64) continue; // Fail on illegal characters

    if (code < 0) return false;
    bitlen += 6;
  } // If there are any bits left, source was corrupted


  return bitlen % 8 === 0;
}

function constructYamlBinary(data) {
  var idx,
      tailbits,
      input = data.replace(/[\r\n=]/g, ''),
      // remove CR/LF & padding to simplify scan
  max = input.length,
      map = BASE64_MAP,
      bits = 0,
      result = []; // Collect by 6*4 bits (3 bytes)

  for (idx = 0; idx < max; idx++) {
    if (idx % 4 === 0 && idx) {
      result.push(bits >> 16 & 0xFF);
      result.push(bits >> 8 & 0xFF);
      result.push(bits & 0xFF);
    }

    bits = bits << 6 | map.indexOf(input.charAt(idx));
  } // Dump tail


  tailbits = max % 4 * 6;

  if (tailbits === 0) {
    result.push(bits >> 16 & 0xFF);
    result.push(bits >> 8 & 0xFF);
    result.push(bits & 0xFF);
  } else if (tailbits === 18) {
    result.push(bits >> 10 & 0xFF);
    result.push(bits >> 2 & 0xFF);
  } else if (tailbits === 12) {
    result.push(bits >> 4 & 0xFF);
  } // Wrap into Buffer for NodeJS and leave Array for browser


  if (NodeBuffer) {
    // Support node 6.+ Buffer API when available
    return NodeBuffer.from ? NodeBuffer.from(result) : new NodeBuffer(result);
  }

  return result;
}

function representYamlBinary(object
/*, style*/
) {
  var result = '',
      bits = 0,
      idx,
      tail,
      max = object.length,
      map = BASE64_MAP; // Convert every three bytes to 4 ASCII characters.

  for (idx = 0; idx < max; idx++) {
    if (idx % 3 === 0 && idx) {
      result += map[bits >> 18 & 0x3F];
      result += map[bits >> 12 & 0x3F];
      result += map[bits >> 6 & 0x3F];
      result += map[bits & 0x3F];
    }

    bits = (bits << 8) + object[idx];
  } // Dump tail


  tail = max % 3;

  if (tail === 0) {
    result += map[bits >> 18 & 0x3F];
    result += map[bits >> 12 & 0x3F];
    result += map[bits >> 6 & 0x3F];
    result += map[bits & 0x3F];
  } else if (tail === 2) {
    result += map[bits >> 10 & 0x3F];
    result += map[bits >> 4 & 0x3F];
    result += map[bits << 2 & 0x3F];
    result += map[64];
  } else if (tail === 1) {
    result += map[bits >> 2 & 0x3F];
    result += map[bits << 4 & 0x3F];
    result += map[64];
    result += map[64];
  }

  return result;
}

function isBinary(object) {
  return NodeBuffer && NodeBuffer.isBuffer(object);
}

var binary = new type('tag:yaml.org,2002:binary', {
  kind: 'scalar',
  resolve: resolveYamlBinary,
  construct: constructYamlBinary,
  predicate: isBinary,
  represent: representYamlBinary
});

var _hasOwnProperty$1 = Object.prototype.hasOwnProperty;
var _toString = Object.prototype.toString;

function resolveYamlOmap(data) {
  if (data === null) return true;
  var objectKeys = [],
      index,
      length,
      pair,
      pairKey,
      pairHasKey,
      object = data;

  for (index = 0, length = object.length; index < length; index += 1) {
    pair = object[index];
    pairHasKey = false;
    if (_toString.call(pair) !== '[object Object]') return false;

    for (pairKey in pair) {
      if (_hasOwnProperty$1.call(pair, pairKey)) {
        if (!pairHasKey) pairHasKey = true;else return false;
      }
    }

    if (!pairHasKey) return false;
    if (objectKeys.indexOf(pairKey) === -1) objectKeys.push(pairKey);else return false;
  }

  return true;
}

function constructYamlOmap(data) {
  return data !== null ? data : [];
}

var omap = new type('tag:yaml.org,2002:omap', {
  kind: 'sequence',
  resolve: resolveYamlOmap,
  construct: constructYamlOmap
});

var _toString$1 = Object.prototype.toString;

function resolveYamlPairs(data) {
  if (data === null) return true;
  var index,
      length,
      pair,
      keys,
      result,
      object = data;
  result = new Array(object.length);

  for (index = 0, length = object.length; index < length; index += 1) {
    pair = object[index];
    if (_toString$1.call(pair) !== '[object Object]') return false;
    keys = Object.keys(pair);
    if (keys.length !== 1) return false;
    result[index] = [keys[0], pair[keys[0]]];
  }

  return true;
}

function constructYamlPairs(data) {
  if (data === null) return [];
  var index,
      length,
      pair,
      keys,
      result,
      object = data;
  result = new Array(object.length);

  for (index = 0, length = object.length; index < length; index += 1) {
    pair = object[index];
    keys = Object.keys(pair);
    result[index] = [keys[0], pair[keys[0]]];
  }

  return result;
}

var pairs = new type('tag:yaml.org,2002:pairs', {
  kind: 'sequence',
  resolve: resolveYamlPairs,
  construct: constructYamlPairs
});

var _hasOwnProperty$2 = Object.prototype.hasOwnProperty;

function resolveYamlSet(data) {
  if (data === null) return true;
  var key,
      object = data;

  for (key in object) {
    if (_hasOwnProperty$2.call(object, key)) {
      if (object[key] !== null) return false;
    }
  }

  return true;
}

function constructYamlSet(data) {
  return data !== null ? data : {};
}

var set$1 = new type('tag:yaml.org,2002:set', {
  kind: 'mapping',
  resolve: resolveYamlSet,
  construct: constructYamlSet
});

var default_safe = new schema({
  include: [core],
  implicit: [timestamp, merge],
  explicit: [binary, omap, pairs, set$1]
});

function resolveJavascriptUndefined() {
  return true;
}

function constructJavascriptUndefined() {
  /*eslint-disable no-undefined*/
  return undefined;
}

function representJavascriptUndefined() {
  return '';
}

function isUndefined(object) {
  return typeof object === 'undefined';
}

var _undefined = new type('tag:yaml.org,2002:js/undefined', {
  kind: 'scalar',
  resolve: resolveJavascriptUndefined,
  construct: constructJavascriptUndefined,
  predicate: isUndefined,
  represent: representJavascriptUndefined
});

function resolveJavascriptRegExp(data) {
  if (data === null) return false;
  if (data.length === 0) return false;
  var regexp = data,
      tail = /\/([gim]*)$/.exec(data),
      modifiers = ''; // if regexp starts with '/' it can have modifiers and must be properly closed
  // `/foo/gim` - modifiers tail can be maximum 3 chars

  if (regexp[0] === '/') {
    if (tail) modifiers = tail[1];
    if (modifiers.length > 3) return false; // if expression starts with /, is should be properly terminated

    if (regexp[regexp.length - modifiers.length - 1] !== '/') return false;
  }

  return true;
}

function constructJavascriptRegExp(data) {
  var regexp = data,
      tail = /\/([gim]*)$/.exec(data),
      modifiers = ''; // `/foo/gim` - tail can be maximum 4 chars

  if (regexp[0] === '/') {
    if (tail) modifiers = tail[1];
    regexp = regexp.slice(1, regexp.length - modifiers.length - 1);
  }

  return new RegExp(regexp, modifiers);
}

function representJavascriptRegExp(object
/*, style*/
) {
  var result = '/' + object.source + '/';
  if (object.global) result += 'g';
  if (object.multiline) result += 'm';
  if (object.ignoreCase) result += 'i';
  return result;
}

function isRegExp(object) {
  return Object.prototype.toString.call(object) === '[object RegExp]';
}

var regexp = new type('tag:yaml.org,2002:js/regexp', {
  kind: 'scalar',
  resolve: resolveJavascriptRegExp,
  construct: constructJavascriptRegExp,
  predicate: isRegExp,
  represent: representJavascriptRegExp
});

var esprima; // Browserified version does not have esprima
//
// 1. For node.js just require module as deps
// 2. For browser try to require mudule via external AMD system.
//    If not found - try to fallback to window.esprima. If not
//    found too - then fail to parse.
//

try {
  // workaround to exclude package from browserify list.
  var _require$1 = commonjsRequire;
  esprima = _require$1('esprima');
} catch (_) {
  /*global window */
  if (typeof window !== 'undefined') esprima = window.esprima;
}

function resolveJavascriptFunction(data) {
  if (data === null) return false;

  try {
    var source = '(' + data + ')',
        ast = esprima.parse(source, {
      range: true
    });

    if (ast.type !== 'Program' || ast.body.length !== 1 || ast.body[0].type !== 'ExpressionStatement' || ast.body[0].expression.type !== 'ArrowFunctionExpression' && ast.body[0].expression.type !== 'FunctionExpression') {
      return false;
    }

    return true;
  } catch (err) {
    return false;
  }
}

function constructJavascriptFunction(data) {
  /*jslint evil:true*/
  var source = '(' + data + ')',
      ast = esprima.parse(source, {
    range: true
  }),
      params = [],
      body;

  if (ast.type !== 'Program' || ast.body.length !== 1 || ast.body[0].type !== 'ExpressionStatement' || ast.body[0].expression.type !== 'ArrowFunctionExpression' && ast.body[0].expression.type !== 'FunctionExpression') {
    throw new Error('Failed to resolve function');
  }

  ast.body[0].expression.params.forEach(function (param) {
    params.push(param.name);
  });
  body = ast.body[0].expression.body.range; // Esprima's ranges include the first '{' and the last '}' characters on
  // function expressions. So cut them out.

  if (ast.body[0].expression.body.type === 'BlockStatement') {
    /*eslint-disable no-new-func*/
    return new Function(params, source.slice(body[0] + 1, body[1] - 1));
  } // ES6 arrow functions can omit the BlockStatement. In that case, just return
  // the body.

  /*eslint-disable no-new-func*/


  return new Function(params, 'return ' + source.slice(body[0], body[1]));
}

function representJavascriptFunction(object
/*, style*/
) {
  return object.toString();
}

function isFunction(object) {
  return Object.prototype.toString.call(object) === '[object Function]';
}

var _function = new type('tag:yaml.org,2002:js/function', {
  kind: 'scalar',
  resolve: resolveJavascriptFunction,
  construct: constructJavascriptFunction,
  predicate: isFunction,
  represent: representJavascriptFunction
});

var default_full = schema.DEFAULT = new schema({
  include: [default_safe],
  explicit: [_undefined, regexp, _function]
});

/*eslint-disable max-len,no-use-before-define*/


var _hasOwnProperty = Object.prototype.hasOwnProperty;
var CONTEXT_FLOW_IN = 1;
var CONTEXT_FLOW_OUT = 2;
var CONTEXT_BLOCK_IN = 3;
var CONTEXT_BLOCK_OUT = 4;
var CHOMPING_CLIP = 1;
var CHOMPING_STRIP = 2;
var CHOMPING_KEEP = 3;
var PATTERN_NON_PRINTABLE = /[\x00-\x08\x0B\x0C\x0E-\x1F\x7F-\x84\x86-\x9F\uFFFE\uFFFF]|[\uD800-\uDBFF](?![\uDC00-\uDFFF])|(?:[^\uD800-\uDBFF]|^)[\uDC00-\uDFFF]/;
var PATTERN_NON_ASCII_LINE_BREAKS = /[\x85\u2028\u2029]/;
var PATTERN_FLOW_INDICATORS = /[,\[\]\{\}]/;
var PATTERN_TAG_HANDLE = /^(?:!|!!|![a-z\-]+!)$/i;
var PATTERN_TAG_URI = /^(?:!|[^,\[\]\{\}])(?:%[0-9a-f]{2}|[0-9a-z\-#;\/\?:@&=\+\$,_\.!~\*'\(\)\[\]])*$/i;

function _class(obj) {
  return Object.prototype.toString.call(obj);
}

function is_EOL(c) {
  return c === 0x0A
  /* LF */
  || c === 0x0D
  /* CR */
  ;
}

function is_WHITE_SPACE(c) {
  return c === 0x09
  /* Tab */
  || c === 0x20
  /* Space */
  ;
}

function is_WS_OR_EOL(c) {
  return c === 0x09
  /* Tab */
  || c === 0x20
  /* Space */
  || c === 0x0A
  /* LF */
  || c === 0x0D
  /* CR */
  ;
}

function is_FLOW_INDICATOR(c) {
  return c === 0x2C
  /* , */
  || c === 0x5B
  /* [ */
  || c === 0x5D
  /* ] */
  || c === 0x7B
  /* { */
  || c === 0x7D
  /* } */
  ;
}

function fromHexCode(c) {
  var lc;

  if (0x30
  /* 0 */
  <= c && c <= 0x39
  /* 9 */
  ) {
    return c - 0x30;
  }
  /*eslint-disable no-bitwise*/


  lc = c | 0x20;

  if (0x61
  /* a */
  <= lc && lc <= 0x66
  /* f */
  ) {
    return lc - 0x61 + 10;
  }

  return -1;
}

function escapedHexLen(c) {
  if (c === 0x78
  /* x */
  ) {
      return 2;
    }

  if (c === 0x75
  /* u */
  ) {
      return 4;
    }

  if (c === 0x55
  /* U */
  ) {
      return 8;
    }

  return 0;
}

function fromDecimalCode(c) {
  if (0x30
  /* 0 */
  <= c && c <= 0x39
  /* 9 */
  ) {
    return c - 0x30;
  }

  return -1;
}

function simpleEscapeSequence(c) {
  /* eslint-disable indent */
  return c === 0x30
  /* 0 */
  ? '\x00' : c === 0x61
  /* a */
  ? '\x07' : c === 0x62
  /* b */
  ? '\x08' : c === 0x74
  /* t */
  ? '\x09' : c === 0x09
  /* Tab */
  ? '\x09' : c === 0x6E
  /* n */
  ? '\x0A' : c === 0x76
  /* v */
  ? '\x0B' : c === 0x66
  /* f */
  ? '\x0C' : c === 0x72
  /* r */
  ? '\x0D' : c === 0x65
  /* e */
  ? '\x1B' : c === 0x20
  /* Space */
  ? ' ' : c === 0x22
  /* " */
  ? '\x22' : c === 0x2F
  /* / */
  ? '/' : c === 0x5C
  /* \ */
  ? '\x5C' : c === 0x4E
  /* N */
  ? '\x85' : c === 0x5F
  /* _ */
  ? '\xA0' : c === 0x4C
  /* L */
  ? '\u2028' : c === 0x50
  /* P */
  ? '\u2029' : '';
}

function charFromCodepoint(c) {
  if (c <= 0xFFFF) {
    return String.fromCharCode(c);
  } // Encode UTF-16 surrogate pair
  // https://en.wikipedia.org/wiki/UTF-16#Code_points_U.2B010000_to_U.2B10FFFF


  return String.fromCharCode((c - 0x010000 >> 10) + 0xD800, (c - 0x010000 & 0x03FF) + 0xDC00);
}

var simpleEscapeCheck = new Array(256); // integer, for fast access

var simpleEscapeMap = new Array(256);

for (var i = 0; i < 256; i++) {
  simpleEscapeCheck[i] = simpleEscapeSequence(i) ? 1 : 0;
  simpleEscapeMap[i] = simpleEscapeSequence(i);
}

function State(input, options) {
  this.input = input;
  this.filename = options['filename'] || null;
  this.schema = options['schema'] || default_full;
  this.onWarning = options['onWarning'] || null;
  this.legacy = options['legacy'] || false;
  this.json = options['json'] || false;
  this.listener = options['listener'] || null;
  this.implicitTypes = this.schema.compiledImplicit;
  this.typeMap = this.schema.compiledTypeMap;
  this.length = input.length;
  this.position = 0;
  this.line = 0;
  this.lineStart = 0;
  this.lineIndent = 0;
  this.documents = [];
  /*
  this.version;
  this.checkLineBreaks;
  this.tagMap;
  this.anchorMap;
  this.tag;
  this.anchor;
  this.kind;
  this.result;*/
}

function generateError(state, message) {
  return new exception(message, new mark(state.filename, state.input, state.position, state.line, state.position - state.lineStart));
}

function throwError(state, message) {
  throw generateError(state, message);
}

function throwWarning(state, message) {
  if (state.onWarning) {
    state.onWarning.call(null, generateError(state, message));
  }
}

var directiveHandlers = {
  YAML: function handleYamlDirective(state, name, args) {
    var match, major, minor;

    if (state.version !== null) {
      throwError(state, 'duplication of %YAML directive');
    }

    if (args.length !== 1) {
      throwError(state, 'YAML directive accepts exactly one argument');
    }

    match = /^([0-9]+)\.([0-9]+)$/.exec(args[0]);

    if (match === null) {
      throwError(state, 'ill-formed argument of the YAML directive');
    }

    major = parseInt(match[1], 10);
    minor = parseInt(match[2], 10);

    if (major !== 1) {
      throwError(state, 'unacceptable YAML version of the document');
    }

    state.version = args[0];
    state.checkLineBreaks = minor < 2;

    if (minor !== 1 && minor !== 2) {
      throwWarning(state, 'unsupported YAML version of the document');
    }
  },
  TAG: function handleTagDirective(state, name, args) {
    var handle, prefix;

    if (args.length !== 2) {
      throwError(state, 'TAG directive accepts exactly two arguments');
    }

    handle = args[0];
    prefix = args[1];

    if (!PATTERN_TAG_HANDLE.test(handle)) {
      throwError(state, 'ill-formed tag handle (first argument) of the TAG directive');
    }

    if (_hasOwnProperty.call(state.tagMap, handle)) {
      throwError(state, 'there is a previously declared suffix for "' + handle + '" tag handle');
    }

    if (!PATTERN_TAG_URI.test(prefix)) {
      throwError(state, 'ill-formed tag prefix (second argument) of the TAG directive');
    }

    state.tagMap[handle] = prefix;
  }
};

function captureSegment(state, start, end, checkJson) {
  var _position, _length, _character, _result;

  if (start < end) {
    _result = state.input.slice(start, end);

    if (checkJson) {
      for (_position = 0, _length = _result.length; _position < _length; _position += 1) {
        _character = _result.charCodeAt(_position);

        if (!(_character === 0x09 || 0x20 <= _character && _character <= 0x10FFFF)) {
          throwError(state, 'expected valid JSON character');
        }
      }
    } else if (PATTERN_NON_PRINTABLE.test(_result)) {
      throwError(state, 'the stream contains non-printable characters');
    }

    state.result += _result;
  }
}

function mergeMappings(state, destination, source, overridableKeys) {
  var sourceKeys, key, index, quantity;

  if (!common.isObject(source)) {
    throwError(state, 'cannot merge mappings; the provided source object is unacceptable');
  }

  sourceKeys = Object.keys(source);

  for (index = 0, quantity = sourceKeys.length; index < quantity; index += 1) {
    key = sourceKeys[index];

    if (!_hasOwnProperty.call(destination, key)) {
      destination[key] = source[key];
      overridableKeys[key] = true;
    }
  }
}

function storeMappingPair(state, _result, overridableKeys, keyTag, keyNode, valueNode, startLine, startPos) {
  var index, quantity; // The output is a plain object here, so keys can only be strings.
  // We need to convert keyNode to a string, but doing so can hang the process
  // (deeply nested arrays that explode exponentially using aliases).

  if (Array.isArray(keyNode)) {
    keyNode = Array.prototype.slice.call(keyNode);

    for (index = 0, quantity = keyNode.length; index < quantity; index += 1) {
      if (Array.isArray(keyNode[index])) {
        throwError(state, 'nested arrays are not supported inside keys');
      }

      if (typeof keyNode === 'object' && _class(keyNode[index]) === '[object Object]') {
        keyNode[index] = '[object Object]';
      }
    }
  } // Avoid code execution in load() via toString property
  // (still use its own toString for arrays, timestamps,
  // and whatever user schema extensions happen to have @@toStringTag)


  if (typeof keyNode === 'object' && _class(keyNode) === '[object Object]') {
    keyNode = '[object Object]';
  }

  keyNode = String(keyNode);

  if (_result === null) {
    _result = {};
  }

  if (keyTag === 'tag:yaml.org,2002:merge') {
    if (Array.isArray(valueNode)) {
      for (index = 0, quantity = valueNode.length; index < quantity; index += 1) {
        mergeMappings(state, _result, valueNode[index], overridableKeys);
      }
    } else {
      mergeMappings(state, _result, valueNode, overridableKeys);
    }
  } else {
    if (!state.json && !_hasOwnProperty.call(overridableKeys, keyNode) && _hasOwnProperty.call(_result, keyNode)) {
      state.line = startLine || state.line;
      state.position = startPos || state.position;
      throwError(state, 'duplicated mapping key');
    }

    _result[keyNode] = valueNode;
    delete overridableKeys[keyNode];
  }

  return _result;
}

function readLineBreak(state) {
  var ch;
  ch = state.input.charCodeAt(state.position);

  if (ch === 0x0A
  /* LF */
  ) {
      state.position++;
    } else if (ch === 0x0D
  /* CR */
  ) {
      state.position++;

      if (state.input.charCodeAt(state.position) === 0x0A
      /* LF */
      ) {
          state.position++;
        }
    } else {
    throwError(state, 'a line break is expected');
  }

  state.line += 1;
  state.lineStart = state.position;
}

function skipSeparationSpace(state, allowComments, checkIndent) {
  var lineBreaks = 0,
      ch = state.input.charCodeAt(state.position);

  while (ch !== 0) {
    while (is_WHITE_SPACE(ch)) {
      ch = state.input.charCodeAt(++state.position);
    }

    if (allowComments && ch === 0x23
    /* # */
    ) {
        do {
          ch = state.input.charCodeAt(++state.position);
        } while (ch !== 0x0A
        /* LF */
        && ch !== 0x0D
        /* CR */
        && ch !== 0);
      }

    if (is_EOL(ch)) {
      readLineBreak(state);
      ch = state.input.charCodeAt(state.position);
      lineBreaks++;
      state.lineIndent = 0;

      while (ch === 0x20
      /* Space */
      ) {
        state.lineIndent++;
        ch = state.input.charCodeAt(++state.position);
      }
    } else {
      break;
    }
  }

  if (checkIndent !== -1 && lineBreaks !== 0 && state.lineIndent < checkIndent) {
    throwWarning(state, 'deficient indentation');
  }

  return lineBreaks;
}

function testDocumentSeparator(state) {
  var _position = state.position,
      ch;
  ch = state.input.charCodeAt(_position); // Condition state.position === state.lineStart is tested
  // in parent on each call, for efficiency. No needs to test here again.

  if ((ch === 0x2D
  /* - */
  || ch === 0x2E
  /* . */
  ) && ch === state.input.charCodeAt(_position + 1) && ch === state.input.charCodeAt(_position + 2)) {
    _position += 3;
    ch = state.input.charCodeAt(_position);

    if (ch === 0 || is_WS_OR_EOL(ch)) {
      return true;
    }
  }

  return false;
}

function writeFoldedLines(state, count) {
  if (count === 1) {
    state.result += ' ';
  } else if (count > 1) {
    state.result += common.repeat('\n', count - 1);
  }
}

function readPlainScalar(state, nodeIndent, withinFlowCollection) {
  var preceding,
      following,
      captureStart,
      captureEnd,
      hasPendingContent,
      _line,
      _lineStart,
      _lineIndent,
      _kind = state.kind,
      _result = state.result,
      ch;

  ch = state.input.charCodeAt(state.position);

  if (is_WS_OR_EOL(ch) || is_FLOW_INDICATOR(ch) || ch === 0x23
  /* # */
  || ch === 0x26
  /* & */
  || ch === 0x2A
  /* * */
  || ch === 0x21
  /* ! */
  || ch === 0x7C
  /* | */
  || ch === 0x3E
  /* > */
  || ch === 0x27
  /* ' */
  || ch === 0x22
  /* " */
  || ch === 0x25
  /* % */
  || ch === 0x40
  /* @ */
  || ch === 0x60
  /* ` */
  ) {
      return false;
    }

  if (ch === 0x3F
  /* ? */
  || ch === 0x2D
  /* - */
  ) {
      following = state.input.charCodeAt(state.position + 1);

      if (is_WS_OR_EOL(following) || withinFlowCollection && is_FLOW_INDICATOR(following)) {
        return false;
      }
    }

  state.kind = 'scalar';
  state.result = '';
  captureStart = captureEnd = state.position;
  hasPendingContent = false;

  while (ch !== 0) {
    if (ch === 0x3A
    /* : */
    ) {
        following = state.input.charCodeAt(state.position + 1);

        if (is_WS_OR_EOL(following) || withinFlowCollection && is_FLOW_INDICATOR(following)) {
          break;
        }
      } else if (ch === 0x23
    /* # */
    ) {
        preceding = state.input.charCodeAt(state.position - 1);

        if (is_WS_OR_EOL(preceding)) {
          break;
        }
      } else if (state.position === state.lineStart && testDocumentSeparator(state) || withinFlowCollection && is_FLOW_INDICATOR(ch)) {
      break;
    } else if (is_EOL(ch)) {
      _line = state.line;
      _lineStart = state.lineStart;
      _lineIndent = state.lineIndent;
      skipSeparationSpace(state, false, -1);

      if (state.lineIndent >= nodeIndent) {
        hasPendingContent = true;
        ch = state.input.charCodeAt(state.position);
        continue;
      } else {
        state.position = captureEnd;
        state.line = _line;
        state.lineStart = _lineStart;
        state.lineIndent = _lineIndent;
        break;
      }
    }

    if (hasPendingContent) {
      captureSegment(state, captureStart, captureEnd, false);
      writeFoldedLines(state, state.line - _line);
      captureStart = captureEnd = state.position;
      hasPendingContent = false;
    }

    if (!is_WHITE_SPACE(ch)) {
      captureEnd = state.position + 1;
    }

    ch = state.input.charCodeAt(++state.position);
  }

  captureSegment(state, captureStart, captureEnd, false);

  if (state.result) {
    return true;
  }

  state.kind = _kind;
  state.result = _result;
  return false;
}

function readSingleQuotedScalar(state, nodeIndent) {
  var ch, captureStart, captureEnd;
  ch = state.input.charCodeAt(state.position);

  if (ch !== 0x27
  /* ' */
  ) {
      return false;
    }

  state.kind = 'scalar';
  state.result = '';
  state.position++;
  captureStart = captureEnd = state.position;

  while ((ch = state.input.charCodeAt(state.position)) !== 0) {
    if (ch === 0x27
    /* ' */
    ) {
        captureSegment(state, captureStart, state.position, true);
        ch = state.input.charCodeAt(++state.position);

        if (ch === 0x27
        /* ' */
        ) {
            captureStart = state.position;
            state.position++;
            captureEnd = state.position;
          } else {
          return true;
        }
      } else if (is_EOL(ch)) {
      captureSegment(state, captureStart, captureEnd, true);
      writeFoldedLines(state, skipSeparationSpace(state, false, nodeIndent));
      captureStart = captureEnd = state.position;
    } else if (state.position === state.lineStart && testDocumentSeparator(state)) {
      throwError(state, 'unexpected end of the document within a single quoted scalar');
    } else {
      state.position++;
      captureEnd = state.position;
    }
  }

  throwError(state, 'unexpected end of the stream within a single quoted scalar');
}

function readDoubleQuotedScalar(state, nodeIndent) {
  var captureStart, captureEnd, hexLength, hexResult, tmp, ch;
  ch = state.input.charCodeAt(state.position);

  if (ch !== 0x22
  /* " */
  ) {
      return false;
    }

  state.kind = 'scalar';
  state.result = '';
  state.position++;
  captureStart = captureEnd = state.position;

  while ((ch = state.input.charCodeAt(state.position)) !== 0) {
    if (ch === 0x22
    /* " */
    ) {
        captureSegment(state, captureStart, state.position, true);
        state.position++;
        return true;
      } else if (ch === 0x5C
    /* \ */
    ) {
        captureSegment(state, captureStart, state.position, true);
        ch = state.input.charCodeAt(++state.position);

        if (is_EOL(ch)) {
          skipSeparationSpace(state, false, nodeIndent); // TODO: rework to inline fn with no type cast?
        } else if (ch < 256 && simpleEscapeCheck[ch]) {
          state.result += simpleEscapeMap[ch];
          state.position++;
        } else if ((tmp = escapedHexLen(ch)) > 0) {
          hexLength = tmp;
          hexResult = 0;

          for (; hexLength > 0; hexLength--) {
            ch = state.input.charCodeAt(++state.position);

            if ((tmp = fromHexCode(ch)) >= 0) {
              hexResult = (hexResult << 4) + tmp;
            } else {
              throwError(state, 'expected hexadecimal character');
            }
          }

          state.result += charFromCodepoint(hexResult);
          state.position++;
        } else {
          throwError(state, 'unknown escape sequence');
        }

        captureStart = captureEnd = state.position;
      } else if (is_EOL(ch)) {
      captureSegment(state, captureStart, captureEnd, true);
      writeFoldedLines(state, skipSeparationSpace(state, false, nodeIndent));
      captureStart = captureEnd = state.position;
    } else if (state.position === state.lineStart && testDocumentSeparator(state)) {
      throwError(state, 'unexpected end of the document within a double quoted scalar');
    } else {
      state.position++;
      captureEnd = state.position;
    }
  }

  throwError(state, 'unexpected end of the stream within a double quoted scalar');
}

function readFlowCollection(state, nodeIndent) {
  var readNext = true,
      _line,
      _tag = state.tag,
      _result,
      _anchor = state.anchor,
      following,
      terminator,
      isPair,
      isExplicitPair,
      isMapping,
      overridableKeys = {},
      keyNode,
      keyTag,
      valueNode,
      ch;

  ch = state.input.charCodeAt(state.position);

  if (ch === 0x5B
  /* [ */
  ) {
      terminator = 0x5D;
      /* ] */

      isMapping = false;
      _result = [];
    } else if (ch === 0x7B
  /* { */
  ) {
      terminator = 0x7D;
      /* } */

      isMapping = true;
      _result = {};
    } else {
    return false;
  }

  if (state.anchor !== null) {
    state.anchorMap[state.anchor] = _result;
  }

  ch = state.input.charCodeAt(++state.position);

  while (ch !== 0) {
    skipSeparationSpace(state, true, nodeIndent);
    ch = state.input.charCodeAt(state.position);

    if (ch === terminator) {
      state.position++;
      state.tag = _tag;
      state.anchor = _anchor;
      state.kind = isMapping ? 'mapping' : 'sequence';
      state.result = _result;
      return true;
    } else if (!readNext) {
      throwError(state, 'missed comma between flow collection entries');
    }

    keyTag = keyNode = valueNode = null;
    isPair = isExplicitPair = false;

    if (ch === 0x3F
    /* ? */
    ) {
        following = state.input.charCodeAt(state.position + 1);

        if (is_WS_OR_EOL(following)) {
          isPair = isExplicitPair = true;
          state.position++;
          skipSeparationSpace(state, true, nodeIndent);
        }
      }

    _line = state.line;
    composeNode(state, nodeIndent, CONTEXT_FLOW_IN, false, true);
    keyTag = state.tag;
    keyNode = state.result;
    skipSeparationSpace(state, true, nodeIndent);
    ch = state.input.charCodeAt(state.position);

    if ((isExplicitPair || state.line === _line) && ch === 0x3A
    /* : */
    ) {
        isPair = true;
        ch = state.input.charCodeAt(++state.position);
        skipSeparationSpace(state, true, nodeIndent);
        composeNode(state, nodeIndent, CONTEXT_FLOW_IN, false, true);
        valueNode = state.result;
      }

    if (isMapping) {
      storeMappingPair(state, _result, overridableKeys, keyTag, keyNode, valueNode);
    } else if (isPair) {
      _result.push(storeMappingPair(state, null, overridableKeys, keyTag, keyNode, valueNode));
    } else {
      _result.push(keyNode);
    }

    skipSeparationSpace(state, true, nodeIndent);
    ch = state.input.charCodeAt(state.position);

    if (ch === 0x2C
    /* , */
    ) {
        readNext = true;
        ch = state.input.charCodeAt(++state.position);
      } else {
      readNext = false;
    }
  }

  throwError(state, 'unexpected end of the stream within a flow collection');
}

function readBlockScalar(state, nodeIndent) {
  var captureStart,
      folding,
      chomping = CHOMPING_CLIP,
      didReadContent = false,
      detectedIndent = false,
      textIndent = nodeIndent,
      emptyLines = 0,
      atMoreIndented = false,
      tmp,
      ch;
  ch = state.input.charCodeAt(state.position);

  if (ch === 0x7C
  /* | */
  ) {
      folding = false;
    } else if (ch === 0x3E
  /* > */
  ) {
      folding = true;
    } else {
    return false;
  }

  state.kind = 'scalar';
  state.result = '';

  while (ch !== 0) {
    ch = state.input.charCodeAt(++state.position);

    if (ch === 0x2B
    /* + */
    || ch === 0x2D
    /* - */
    ) {
        if (CHOMPING_CLIP === chomping) {
          chomping = ch === 0x2B
          /* + */
          ? CHOMPING_KEEP : CHOMPING_STRIP;
        } else {
          throwError(state, 'repeat of a chomping mode identifier');
        }
      } else if ((tmp = fromDecimalCode(ch)) >= 0) {
      if (tmp === 0) {
        throwError(state, 'bad explicit indentation width of a block scalar; it cannot be less than one');
      } else if (!detectedIndent) {
        textIndent = nodeIndent + tmp - 1;
        detectedIndent = true;
      } else {
        throwError(state, 'repeat of an indentation width identifier');
      }
    } else {
      break;
    }
  }

  if (is_WHITE_SPACE(ch)) {
    do {
      ch = state.input.charCodeAt(++state.position);
    } while (is_WHITE_SPACE(ch));

    if (ch === 0x23
    /* # */
    ) {
        do {
          ch = state.input.charCodeAt(++state.position);
        } while (!is_EOL(ch) && ch !== 0);
      }
  }

  while (ch !== 0) {
    readLineBreak(state);
    state.lineIndent = 0;
    ch = state.input.charCodeAt(state.position);

    while ((!detectedIndent || state.lineIndent < textIndent) && ch === 0x20
    /* Space */
    ) {
      state.lineIndent++;
      ch = state.input.charCodeAt(++state.position);
    }

    if (!detectedIndent && state.lineIndent > textIndent) {
      textIndent = state.lineIndent;
    }

    if (is_EOL(ch)) {
      emptyLines++;
      continue;
    } // End of the scalar.


    if (state.lineIndent < textIndent) {
      // Perform the chomping.
      if (chomping === CHOMPING_KEEP) {
        state.result += common.repeat('\n', didReadContent ? 1 + emptyLines : emptyLines);
      } else if (chomping === CHOMPING_CLIP) {
        if (didReadContent) {
          // i.e. only if the scalar is not empty.
          state.result += '\n';
        }
      } // Break this `while` cycle and go to the funciton's epilogue.


      break;
    } // Folded style: use fancy rules to handle line breaks.


    if (folding) {
      // Lines starting with white space characters (more-indented lines) are not folded.
      if (is_WHITE_SPACE(ch)) {
        atMoreIndented = true; // except for the first content line (cf. Example 8.1)

        state.result += common.repeat('\n', didReadContent ? 1 + emptyLines : emptyLines); // End of more-indented block.
      } else if (atMoreIndented) {
        atMoreIndented = false;
        state.result += common.repeat('\n', emptyLines + 1); // Just one line break - perceive as the same line.
      } else if (emptyLines === 0) {
        if (didReadContent) {
          // i.e. only if we have already read some scalar content.
          state.result += ' ';
        } // Several line breaks - perceive as different lines.

      } else {
        state.result += common.repeat('\n', emptyLines);
      } // Literal style: just add exact number of line breaks between content lines.

    } else {
      // Keep all line breaks except the header line break.
      state.result += common.repeat('\n', didReadContent ? 1 + emptyLines : emptyLines);
    }

    didReadContent = true;
    detectedIndent = true;
    emptyLines = 0;
    captureStart = state.position;

    while (!is_EOL(ch) && ch !== 0) {
      ch = state.input.charCodeAt(++state.position);
    }

    captureSegment(state, captureStart, state.position, false);
  }

  return true;
}

function readBlockSequence(state, nodeIndent) {
  var _line,
      _tag = state.tag,
      _anchor = state.anchor,
      _result = [],
      following,
      detected = false,
      ch;

  if (state.anchor !== null) {
    state.anchorMap[state.anchor] = _result;
  }

  ch = state.input.charCodeAt(state.position);

  while (ch !== 0) {
    if (ch !== 0x2D
    /* - */
    ) {
        break;
      }

    following = state.input.charCodeAt(state.position + 1);

    if (!is_WS_OR_EOL(following)) {
      break;
    }

    detected = true;
    state.position++;

    if (skipSeparationSpace(state, true, -1)) {
      if (state.lineIndent <= nodeIndent) {
        _result.push(null);

        ch = state.input.charCodeAt(state.position);
        continue;
      }
    }

    _line = state.line;
    composeNode(state, nodeIndent, CONTEXT_BLOCK_IN, false, true);

    _result.push(state.result);

    skipSeparationSpace(state, true, -1);
    ch = state.input.charCodeAt(state.position);

    if ((state.line === _line || state.lineIndent > nodeIndent) && ch !== 0) {
      throwError(state, 'bad indentation of a sequence entry');
    } else if (state.lineIndent < nodeIndent) {
      break;
    }
  }

  if (detected) {
    state.tag = _tag;
    state.anchor = _anchor;
    state.kind = 'sequence';
    state.result = _result;
    return true;
  }

  return false;
}

function readBlockMapping(state, nodeIndent, flowIndent) {
  var following,
      allowCompact,
      _line,
      _pos,
      _tag = state.tag,
      _anchor = state.anchor,
      _result = {},
      overridableKeys = {},
      keyTag = null,
      keyNode = null,
      valueNode = null,
      atExplicitKey = false,
      detected = false,
      ch;

  if (state.anchor !== null) {
    state.anchorMap[state.anchor] = _result;
  }

  ch = state.input.charCodeAt(state.position);

  while (ch !== 0) {
    following = state.input.charCodeAt(state.position + 1);
    _line = state.line; // Save the current line.

    _pos = state.position; //
    // Explicit notation case. There are two separate blocks:
    // first for the key (denoted by "?") and second for the value (denoted by ":")
    //

    if ((ch === 0x3F
    /* ? */
    || ch === 0x3A
    /* : */
    ) && is_WS_OR_EOL(following)) {
      if (ch === 0x3F
      /* ? */
      ) {
          if (atExplicitKey) {
            storeMappingPair(state, _result, overridableKeys, keyTag, keyNode, null);
            keyTag = keyNode = valueNode = null;
          }

          detected = true;
          atExplicitKey = true;
          allowCompact = true;
        } else if (atExplicitKey) {
        // i.e. 0x3A/* : */ === character after the explicit key.
        atExplicitKey = false;
        allowCompact = true;
      } else {
        throwError(state, 'incomplete explicit mapping pair; a key node is missed; or followed by a non-tabulated empty line');
      }

      state.position += 1;
      ch = following; //
      // Implicit notation case. Flow-style node as the key first, then ":", and the value.
      //
    } else if (composeNode(state, flowIndent, CONTEXT_FLOW_OUT, false, true)) {
      if (state.line === _line) {
        ch = state.input.charCodeAt(state.position);

        while (is_WHITE_SPACE(ch)) {
          ch = state.input.charCodeAt(++state.position);
        }

        if (ch === 0x3A
        /* : */
        ) {
            ch = state.input.charCodeAt(++state.position);

            if (!is_WS_OR_EOL(ch)) {
              throwError(state, 'a whitespace character is expected after the key-value separator within a block mapping');
            }

            if (atExplicitKey) {
              storeMappingPair(state, _result, overridableKeys, keyTag, keyNode, null);
              keyTag = keyNode = valueNode = null;
            }

            detected = true;
            atExplicitKey = false;
            allowCompact = false;
            keyTag = state.tag;
            keyNode = state.result;
          } else if (detected) {
          throwError(state, 'can not read an implicit mapping pair; a colon is missed');
        } else {
          state.tag = _tag;
          state.anchor = _anchor;
          return true; // Keep the result of `composeNode`.
        }
      } else if (detected) {
        throwError(state, 'can not read a block mapping entry; a multiline key may not be an implicit key');
      } else {
        state.tag = _tag;
        state.anchor = _anchor;
        return true; // Keep the result of `composeNode`.
      }
    } else {
        break; // Reading is done. Go to the epilogue.
      } //
    // Common reading code for both explicit and implicit notations.
    //


    if (state.line === _line || state.lineIndent > nodeIndent) {
      if (composeNode(state, nodeIndent, CONTEXT_BLOCK_OUT, true, allowCompact)) {
        if (atExplicitKey) {
          keyNode = state.result;
        } else {
          valueNode = state.result;
        }
      }

      if (!atExplicitKey) {
        storeMappingPair(state, _result, overridableKeys, keyTag, keyNode, valueNode, _line, _pos);
        keyTag = keyNode = valueNode = null;
      }

      skipSeparationSpace(state, true, -1);
      ch = state.input.charCodeAt(state.position);
    }

    if (state.lineIndent > nodeIndent && ch !== 0) {
      throwError(state, 'bad indentation of a mapping entry');
    } else if (state.lineIndent < nodeIndent) {
      break;
    }
  } //
  // Epilogue.
  //
  // Special case: last mapping's node contains only the key in explicit notation.


  if (atExplicitKey) {
    storeMappingPair(state, _result, overridableKeys, keyTag, keyNode, null);
  } // Expose the resulting mapping.


  if (detected) {
    state.tag = _tag;
    state.anchor = _anchor;
    state.kind = 'mapping';
    state.result = _result;
  }

  return detected;
}

function readTagProperty(state) {
  var _position,
      isVerbatim = false,
      isNamed = false,
      tagHandle,
      tagName,
      ch;

  ch = state.input.charCodeAt(state.position);
  if (ch !== 0x21
  /* ! */
  ) return false;

  if (state.tag !== null) {
    throwError(state, 'duplication of a tag property');
  }

  ch = state.input.charCodeAt(++state.position);

  if (ch === 0x3C
  /* < */
  ) {
      isVerbatim = true;
      ch = state.input.charCodeAt(++state.position);
    } else if (ch === 0x21
  /* ! */
  ) {
      isNamed = true;
      tagHandle = '!!';
      ch = state.input.charCodeAt(++state.position);
    } else {
    tagHandle = '!';
  }

  _position = state.position;

  if (isVerbatim) {
    do {
      ch = state.input.charCodeAt(++state.position);
    } while (ch !== 0 && ch !== 0x3E
    /* > */
    );

    if (state.position < state.length) {
      tagName = state.input.slice(_position, state.position);
      ch = state.input.charCodeAt(++state.position);
    } else {
      throwError(state, 'unexpected end of the stream within a verbatim tag');
    }
  } else {
    while (ch !== 0 && !is_WS_OR_EOL(ch)) {
      if (ch === 0x21
      /* ! */
      ) {
          if (!isNamed) {
            tagHandle = state.input.slice(_position - 1, state.position + 1);

            if (!PATTERN_TAG_HANDLE.test(tagHandle)) {
              throwError(state, 'named tag handle cannot contain such characters');
            }

            isNamed = true;
            _position = state.position + 1;
          } else {
            throwError(state, 'tag suffix cannot contain exclamation marks');
          }
        }

      ch = state.input.charCodeAt(++state.position);
    }

    tagName = state.input.slice(_position, state.position);

    if (PATTERN_FLOW_INDICATORS.test(tagName)) {
      throwError(state, 'tag suffix cannot contain flow indicator characters');
    }
  }

  if (tagName && !PATTERN_TAG_URI.test(tagName)) {
    throwError(state, 'tag name cannot contain such characters: ' + tagName);
  }

  if (isVerbatim) {
    state.tag = tagName;
  } else if (_hasOwnProperty.call(state.tagMap, tagHandle)) {
    state.tag = state.tagMap[tagHandle] + tagName;
  } else if (tagHandle === '!') {
    state.tag = '!' + tagName;
  } else if (tagHandle === '!!') {
    state.tag = 'tag:yaml.org,2002:' + tagName;
  } else {
    throwError(state, 'undeclared tag handle "' + tagHandle + '"');
  }

  return true;
}

function readAnchorProperty(state) {
  var _position, ch;

  ch = state.input.charCodeAt(state.position);
  if (ch !== 0x26
  /* & */
  ) return false;

  if (state.anchor !== null) {
    throwError(state, 'duplication of an anchor property');
  }

  ch = state.input.charCodeAt(++state.position);
  _position = state.position;

  while (ch !== 0 && !is_WS_OR_EOL(ch) && !is_FLOW_INDICATOR(ch)) {
    ch = state.input.charCodeAt(++state.position);
  }

  if (state.position === _position) {
    throwError(state, 'name of an anchor node must contain at least one character');
  }

  state.anchor = state.input.slice(_position, state.position);
  return true;
}

function readAlias(state) {
  var _position, alias, ch;

  ch = state.input.charCodeAt(state.position);
  if (ch !== 0x2A
  /* * */
  ) return false;
  ch = state.input.charCodeAt(++state.position);
  _position = state.position;

  while (ch !== 0 && !is_WS_OR_EOL(ch) && !is_FLOW_INDICATOR(ch)) {
    ch = state.input.charCodeAt(++state.position);
  }

  if (state.position === _position) {
    throwError(state, 'name of an alias node must contain at least one character');
  }

  alias = state.input.slice(_position, state.position);

  if (!state.anchorMap.hasOwnProperty(alias)) {
    throwError(state, 'unidentified alias "' + alias + '"');
  }

  state.result = state.anchorMap[alias];
  skipSeparationSpace(state, true, -1);
  return true;
}

function composeNode(state, parentIndent, nodeContext, allowToSeek, allowCompact) {
  var allowBlockStyles,
      allowBlockScalars,
      allowBlockCollections,
      indentStatus = 1,
      // 1: this>parent, 0: this=parent, -1: this<parent
  atNewLine = false,
      hasContent = false,
      typeIndex,
      typeQuantity,
      type,
      flowIndent,
      blockIndent;

  if (state.listener !== null) {
    state.listener('open', state);
  }

  state.tag = null;
  state.anchor = null;
  state.kind = null;
  state.result = null;
  allowBlockStyles = allowBlockScalars = allowBlockCollections = CONTEXT_BLOCK_OUT === nodeContext || CONTEXT_BLOCK_IN === nodeContext;

  if (allowToSeek) {
    if (skipSeparationSpace(state, true, -1)) {
      atNewLine = true;

      if (state.lineIndent > parentIndent) {
        indentStatus = 1;
      } else if (state.lineIndent === parentIndent) {
        indentStatus = 0;
      } else if (state.lineIndent < parentIndent) {
        indentStatus = -1;
      }
    }
  }

  if (indentStatus === 1) {
    while (readTagProperty(state) || readAnchorProperty(state)) {
      if (skipSeparationSpace(state, true, -1)) {
        atNewLine = true;
        allowBlockCollections = allowBlockStyles;

        if (state.lineIndent > parentIndent) {
          indentStatus = 1;
        } else if (state.lineIndent === parentIndent) {
          indentStatus = 0;
        } else if (state.lineIndent < parentIndent) {
          indentStatus = -1;
        }
      } else {
        allowBlockCollections = false;
      }
    }
  }

  if (allowBlockCollections) {
    allowBlockCollections = atNewLine || allowCompact;
  }

  if (indentStatus === 1 || CONTEXT_BLOCK_OUT === nodeContext) {
    if (CONTEXT_FLOW_IN === nodeContext || CONTEXT_FLOW_OUT === nodeContext) {
      flowIndent = parentIndent;
    } else {
      flowIndent = parentIndent + 1;
    }

    blockIndent = state.position - state.lineStart;

    if (indentStatus === 1) {
      if (allowBlockCollections && (readBlockSequence(state, blockIndent) || readBlockMapping(state, blockIndent, flowIndent)) || readFlowCollection(state, flowIndent)) {
        hasContent = true;
      } else {
        if (allowBlockScalars && readBlockScalar(state, flowIndent) || readSingleQuotedScalar(state, flowIndent) || readDoubleQuotedScalar(state, flowIndent)) {
          hasContent = true;
        } else if (readAlias(state)) {
          hasContent = true;

          if (state.tag !== null || state.anchor !== null) {
            throwError(state, 'alias node should not have any properties');
          }
        } else if (readPlainScalar(state, flowIndent, CONTEXT_FLOW_IN === nodeContext)) {
          hasContent = true;

          if (state.tag === null) {
            state.tag = '?';
          }
        }

        if (state.anchor !== null) {
          state.anchorMap[state.anchor] = state.result;
        }
      }
    } else if (indentStatus === 0) {
      // Special case: block sequences are allowed to have same indentation level as the parent.
      // http://www.yaml.org/spec/1.2/spec.html#id2799784
      hasContent = allowBlockCollections && readBlockSequence(state, blockIndent);
    }
  }

  if (state.tag !== null && state.tag !== '!') {
    if (state.tag === '?') {
      for (typeIndex = 0, typeQuantity = state.implicitTypes.length; typeIndex < typeQuantity; typeIndex += 1) {
        type = state.implicitTypes[typeIndex]; // Implicit resolving is not allowed for non-scalar types, and '?'
        // non-specific tag is only assigned to plain scalars. So, it isn't
        // needed to check for 'kind' conformity.

        if (type.resolve(state.result)) {
          // `state.result` updated in resolver if matched
          state.result = type.construct(state.result);
          state.tag = type.tag;

          if (state.anchor !== null) {
            state.anchorMap[state.anchor] = state.result;
          }

          break;
        }
      }
    } else if (_hasOwnProperty.call(state.typeMap[state.kind || 'fallback'], state.tag)) {
      type = state.typeMap[state.kind || 'fallback'][state.tag];

      if (state.result !== null && type.kind !== state.kind) {
        throwError(state, 'unacceptable node kind for !<' + state.tag + '> tag; it should be "' + type.kind + '", not "' + state.kind + '"');
      }

      if (!type.resolve(state.result)) {
        // `state.result` updated in resolver if matched
        throwError(state, 'cannot resolve a node with !<' + state.tag + '> explicit tag');
      } else {
        state.result = type.construct(state.result);

        if (state.anchor !== null) {
          state.anchorMap[state.anchor] = state.result;
        }
      }
    } else {
      throwError(state, 'unknown tag !<' + state.tag + '>');
    }
  }

  if (state.listener !== null) {
    state.listener('close', state);
  }

  return state.tag !== null || state.anchor !== null || hasContent;
}

function readDocument(state) {
  var documentStart = state.position,
      _position,
      directiveName,
      directiveArgs,
      hasDirectives = false,
      ch;

  state.version = null;
  state.checkLineBreaks = state.legacy;
  state.tagMap = {};
  state.anchorMap = {};

  while ((ch = state.input.charCodeAt(state.position)) !== 0) {
    skipSeparationSpace(state, true, -1);
    ch = state.input.charCodeAt(state.position);

    if (state.lineIndent > 0 || ch !== 0x25
    /* % */
    ) {
        break;
      }

    hasDirectives = true;
    ch = state.input.charCodeAt(++state.position);
    _position = state.position;

    while (ch !== 0 && !is_WS_OR_EOL(ch)) {
      ch = state.input.charCodeAt(++state.position);
    }

    directiveName = state.input.slice(_position, state.position);
    directiveArgs = [];

    if (directiveName.length < 1) {
      throwError(state, 'directive name must not be less than one character in length');
    }

    while (ch !== 0) {
      while (is_WHITE_SPACE(ch)) {
        ch = state.input.charCodeAt(++state.position);
      }

      if (ch === 0x23
      /* # */
      ) {
          do {
            ch = state.input.charCodeAt(++state.position);
          } while (ch !== 0 && !is_EOL(ch));

          break;
        }

      if (is_EOL(ch)) break;
      _position = state.position;

      while (ch !== 0 && !is_WS_OR_EOL(ch)) {
        ch = state.input.charCodeAt(++state.position);
      }

      directiveArgs.push(state.input.slice(_position, state.position));
    }

    if (ch !== 0) readLineBreak(state);

    if (_hasOwnProperty.call(directiveHandlers, directiveName)) {
      directiveHandlers[directiveName](state, directiveName, directiveArgs);
    } else {
      throwWarning(state, 'unknown document directive "' + directiveName + '"');
    }
  }

  skipSeparationSpace(state, true, -1);

  if (state.lineIndent === 0 && state.input.charCodeAt(state.position) === 0x2D
  /* - */
  && state.input.charCodeAt(state.position + 1) === 0x2D
  /* - */
  && state.input.charCodeAt(state.position + 2) === 0x2D
  /* - */
  ) {
      state.position += 3;
      skipSeparationSpace(state, true, -1);
    } else if (hasDirectives) {
    throwError(state, 'directives end mark is expected');
  }

  composeNode(state, state.lineIndent - 1, CONTEXT_BLOCK_OUT, false, true);
  skipSeparationSpace(state, true, -1);

  if (state.checkLineBreaks && PATTERN_NON_ASCII_LINE_BREAKS.test(state.input.slice(documentStart, state.position))) {
    throwWarning(state, 'non-ASCII line breaks are interpreted as content');
  }

  state.documents.push(state.result);

  if (state.position === state.lineStart && testDocumentSeparator(state)) {
    if (state.input.charCodeAt(state.position) === 0x2E
    /* . */
    ) {
        state.position += 3;
        skipSeparationSpace(state, true, -1);
      }

    return;
  }

  if (state.position < state.length - 1) {
    throwError(state, 'end of the stream or a document separator is expected');
  } else {
    return;
  }
}

function loadDocuments(input, options) {
  input = String(input);
  options = options || {};

  if (input.length !== 0) {
    // Add tailing `\n` if not exists
    if (input.charCodeAt(input.length - 1) !== 0x0A
    /* LF */
    && input.charCodeAt(input.length - 1) !== 0x0D
    /* CR */
    ) {
        input += '\n';
      } // Strip BOM


    if (input.charCodeAt(0) === 0xFEFF) {
      input = input.slice(1);
    }
  }

  var state = new State(input, options); // Use 0 as string terminator. That significantly simplifies bounds check.

  state.input += '\0';

  while (state.input.charCodeAt(state.position) === 0x20
  /* Space */
  ) {
    state.lineIndent += 1;
    state.position += 1;
  }

  while (state.position < state.length - 1) {
    readDocument(state);
  }

  return state.documents;
}

function loadAll$1(input, iterator, options) {
  var documents = loadDocuments(input, options),
      index,
      length;

  if (typeof iterator !== 'function') {
    return documents;
  }

  for (index = 0, length = documents.length; index < length; index += 1) {
    iterator(documents[index]);
  }
}

function load$1(input, options) {
  var documents = loadDocuments(input, options);

  if (documents.length === 0) {
    /*eslint-disable no-undefined*/
    return undefined;
  } else if (documents.length === 1) {
    return documents[0];
  }

  throw new exception('expected a single document in the stream, but found more');
}

function safeLoadAll$1(input, output, options) {
  if (typeof output === 'function') {
    loadAll$1(input, output, common.extend({
      schema: default_safe
    }, options));
  } else {
    return loadAll$1(input, common.extend({
      schema: default_safe
    }, options));
  }
}

function safeLoad$1(input, options) {
  return load$1(input, common.extend({
    schema: default_safe
  }, options));
}

var loadAll_1 = loadAll$1;
var load_1 = load$1;
var safeLoadAll_1 = safeLoadAll$1;
var safeLoad_1 = safeLoad$1;
var loader = {
  loadAll: loadAll_1,
  load: load_1,
  safeLoadAll: safeLoadAll_1,
  safeLoad: safeLoad_1
};

/*eslint-disable no-use-before-define*/


var _toString$2 = Object.prototype.toString;
var _hasOwnProperty$3 = Object.prototype.hasOwnProperty;
var CHAR_TAB = 0x09;
/* Tab */

var CHAR_LINE_FEED = 0x0A;
/* LF */

var CHAR_SPACE = 0x20;
/* Space */

var CHAR_EXCLAMATION = 0x21;
/* ! */

var CHAR_DOUBLE_QUOTE = 0x22;
/* " */

var CHAR_SHARP = 0x23;
/* # */

var CHAR_PERCENT = 0x25;
/* % */

var CHAR_AMPERSAND = 0x26;
/* & */

var CHAR_SINGLE_QUOTE = 0x27;
/* ' */

var CHAR_ASTERISK = 0x2A;
/* * */

var CHAR_COMMA = 0x2C;
/* , */

var CHAR_MINUS = 0x2D;
/* - */

var CHAR_COLON = 0x3A;
/* : */

var CHAR_GREATER_THAN = 0x3E;
/* > */

var CHAR_QUESTION = 0x3F;
/* ? */

var CHAR_COMMERCIAL_AT = 0x40;
/* @ */

var CHAR_LEFT_SQUARE_BRACKET = 0x5B;
/* [ */

var CHAR_RIGHT_SQUARE_BRACKET = 0x5D;
/* ] */

var CHAR_GRAVE_ACCENT = 0x60;
/* ` */

var CHAR_LEFT_CURLY_BRACKET = 0x7B;
/* { */

var CHAR_VERTICAL_LINE = 0x7C;
/* | */

var CHAR_RIGHT_CURLY_BRACKET = 0x7D;
/* } */

var ESCAPE_SEQUENCES = {};
ESCAPE_SEQUENCES[0x00] = '\\0';
ESCAPE_SEQUENCES[0x07] = '\\a';
ESCAPE_SEQUENCES[0x08] = '\\b';
ESCAPE_SEQUENCES[0x09] = '\\t';
ESCAPE_SEQUENCES[0x0A] = '\\n';
ESCAPE_SEQUENCES[0x0B] = '\\v';
ESCAPE_SEQUENCES[0x0C] = '\\f';
ESCAPE_SEQUENCES[0x0D] = '\\r';
ESCAPE_SEQUENCES[0x1B] = '\\e';
ESCAPE_SEQUENCES[0x22] = '\\"';
ESCAPE_SEQUENCES[0x5C] = '\\\\';
ESCAPE_SEQUENCES[0x85] = '\\N';
ESCAPE_SEQUENCES[0xA0] = '\\_';
ESCAPE_SEQUENCES[0x2028] = '\\L';
ESCAPE_SEQUENCES[0x2029] = '\\P';
var DEPRECATED_BOOLEANS_SYNTAX = ['y', 'Y', 'yes', 'Yes', 'YES', 'on', 'On', 'ON', 'n', 'N', 'no', 'No', 'NO', 'off', 'Off', 'OFF'];

function compileStyleMap(schema, map) {
  var result, keys, index, length, tag, style, type;
  if (map === null) return {};
  result = {};
  keys = Object.keys(map);

  for (index = 0, length = keys.length; index < length; index += 1) {
    tag = keys[index];
    style = String(map[tag]);

    if (tag.slice(0, 2) === '!!') {
      tag = 'tag:yaml.org,2002:' + tag.slice(2);
    }

    type = schema.compiledTypeMap['fallback'][tag];

    if (type && _hasOwnProperty$3.call(type.styleAliases, style)) {
      style = type.styleAliases[style];
    }

    result[tag] = style;
  }

  return result;
}

function encodeHex(character) {
  var string, handle, length;
  string = character.toString(16).toUpperCase();

  if (character <= 0xFF) {
    handle = 'x';
    length = 2;
  } else if (character <= 0xFFFF) {
    handle = 'u';
    length = 4;
  } else if (character <= 0xFFFFFFFF) {
    handle = 'U';
    length = 8;
  } else {
    throw new exception('code point within a string may not be greater than 0xFFFFFFFF');
  }

  return '\\' + handle + common.repeat('0', length - string.length) + string;
}

function State$1(options) {
  this.schema = options['schema'] || default_full;
  this.indent = Math.max(1, options['indent'] || 2);
  this.noArrayIndent = options['noArrayIndent'] || false;
  this.skipInvalid = options['skipInvalid'] || false;
  this.flowLevel = common.isNothing(options['flowLevel']) ? -1 : options['flowLevel'];
  this.styleMap = compileStyleMap(this.schema, options['styles'] || null);
  this.sortKeys = options['sortKeys'] || false;
  this.lineWidth = options['lineWidth'] || 80;
  this.noRefs = options['noRefs'] || false;
  this.noCompatMode = options['noCompatMode'] || false;
  this.condenseFlow = options['condenseFlow'] || false;
  this.implicitTypes = this.schema.compiledImplicit;
  this.explicitTypes = this.schema.compiledExplicit;
  this.tag = null;
  this.result = '';
  this.duplicates = [];
  this.usedDuplicates = null;
} // Indents every line in a string. Empty lines (\n only) are not indented.


function indentString(string, spaces) {
  var ind = common.repeat(' ', spaces),
      position = 0,
      next = -1,
      result = '',
      line,
      length = string.length;

  while (position < length) {
    next = string.indexOf('\n', position);

    if (next === -1) {
      line = string.slice(position);
      position = length;
    } else {
      line = string.slice(position, next + 1);
      position = next + 1;
    }

    if (line.length && line !== '\n') result += ind;
    result += line;
  }

  return result;
}

function generateNextLine(state, level) {
  return '\n' + common.repeat(' ', state.indent * level);
}

function testImplicitResolving(state, str) {
  var index, length, type;

  for (index = 0, length = state.implicitTypes.length; index < length; index += 1) {
    type = state.implicitTypes[index];

    if (type.resolve(str)) {
      return true;
    }
  }

  return false;
} // [33] s-white ::= s-space | s-tab


function isWhitespace(c) {
  return c === CHAR_SPACE || c === CHAR_TAB;
} // Returns true if the character can be printed without escaping.
// From YAML 1.2: "any allowed characters known to be non-printable
// should also be escaped. [However,] This isn’t mandatory"
// Derived from nb-char - \t - #x85 - #xA0 - #x2028 - #x2029.


function isPrintable(c) {
  return 0x00020 <= c && c <= 0x00007E || 0x000A1 <= c && c <= 0x00D7FF && c !== 0x2028 && c !== 0x2029 || 0x0E000 <= c && c <= 0x00FFFD && c !== 0xFEFF
  /* BOM */
  || 0x10000 <= c && c <= 0x10FFFF;
} // Simplified test for values allowed after the first character in plain style.


function isPlainSafe(c) {
  // Uses a subset of nb-char - c-flow-indicator - ":" - "#"
  // where nb-char ::= c-printable - b-char - c-byte-order-mark.
  return isPrintable(c) && c !== 0xFEFF // - c-flow-indicator
  && c !== CHAR_COMMA && c !== CHAR_LEFT_SQUARE_BRACKET && c !== CHAR_RIGHT_SQUARE_BRACKET && c !== CHAR_LEFT_CURLY_BRACKET && c !== CHAR_RIGHT_CURLY_BRACKET // - ":" - "#"
  && c !== CHAR_COLON && c !== CHAR_SHARP;
} // Simplified test for values allowed as the first character in plain style.


function isPlainSafeFirst(c) {
  // Uses a subset of ns-char - c-indicator
  // where ns-char = nb-char - s-white.
  return isPrintable(c) && c !== 0xFEFF && !isWhitespace(c) // - s-white
  // - (c-indicator ::=
  // “-” | “?” | “:” | “,” | “[” | “]” | “{” | “}”
  && c !== CHAR_MINUS && c !== CHAR_QUESTION && c !== CHAR_COLON && c !== CHAR_COMMA && c !== CHAR_LEFT_SQUARE_BRACKET && c !== CHAR_RIGHT_SQUARE_BRACKET && c !== CHAR_LEFT_CURLY_BRACKET && c !== CHAR_RIGHT_CURLY_BRACKET // | “#” | “&” | “*” | “!” | “|” | “>” | “'” | “"”
  && c !== CHAR_SHARP && c !== CHAR_AMPERSAND && c !== CHAR_ASTERISK && c !== CHAR_EXCLAMATION && c !== CHAR_VERTICAL_LINE && c !== CHAR_GREATER_THAN && c !== CHAR_SINGLE_QUOTE && c !== CHAR_DOUBLE_QUOTE // | “%” | “@” | “`”)
  && c !== CHAR_PERCENT && c !== CHAR_COMMERCIAL_AT && c !== CHAR_GRAVE_ACCENT;
} // Determines whether block indentation indicator is required.


function needIndentIndicator(string) {
  var leadingSpaceRe = /^\n* /;
  return leadingSpaceRe.test(string);
}

var STYLE_PLAIN = 1;
var STYLE_SINGLE = 2;
var STYLE_LITERAL = 3;
var STYLE_FOLDED = 4;
var STYLE_DOUBLE = 5; // Determines which scalar styles are possible and returns the preferred style.
// lineWidth = -1 => no limit.
// Pre-conditions: str.length > 0.
// Post-conditions:
//    STYLE_PLAIN or STYLE_SINGLE => no \n are in the string.
//    STYLE_LITERAL => no lines are suitable for folding (or lineWidth is -1).
//    STYLE_FOLDED => a line > lineWidth and can be folded (and lineWidth != -1).

function chooseScalarStyle(string, singleLineOnly, indentPerLevel, lineWidth, testAmbiguousType) {
  var i;
  var char;
  var hasLineBreak = false;
  var hasFoldableLine = false; // only checked if shouldTrackWidth

  var shouldTrackWidth = lineWidth !== -1;
  var previousLineBreak = -1; // count the first line correctly

  var plain = isPlainSafeFirst(string.charCodeAt(0)) && !isWhitespace(string.charCodeAt(string.length - 1));

  if (singleLineOnly) {
    // Case: no block styles.
    // Check for disallowed characters to rule out plain and single.
    for (i = 0; i < string.length; i++) {
      char = string.charCodeAt(i);

      if (!isPrintable(char)) {
        return STYLE_DOUBLE;
      }

      plain = plain && isPlainSafe(char);
    }
  } else {
    // Case: block styles permitted.
    for (i = 0; i < string.length; i++) {
      char = string.charCodeAt(i);

      if (char === CHAR_LINE_FEED) {
        hasLineBreak = true; // Check if any line can be folded.

        if (shouldTrackWidth) {
          hasFoldableLine = hasFoldableLine || // Foldable line = too long, and not more-indented.
          i - previousLineBreak - 1 > lineWidth && string[previousLineBreak + 1] !== ' ';
          previousLineBreak = i;
        }
      } else if (!isPrintable(char)) {
        return STYLE_DOUBLE;
      }

      plain = plain && isPlainSafe(char);
    } // in case the end is missing a \n


    hasFoldableLine = hasFoldableLine || shouldTrackWidth && i - previousLineBreak - 1 > lineWidth && string[previousLineBreak + 1] !== ' ';
  } // Although every style can represent \n without escaping, prefer block styles
  // for multiline, since they're more readable and they don't add empty lines.
  // Also prefer folding a super-long line.


  if (!hasLineBreak && !hasFoldableLine) {
    // Strings interpretable as another type have to be quoted;
    // e.g. the string 'true' vs. the boolean true.
    return plain && !testAmbiguousType(string) ? STYLE_PLAIN : STYLE_SINGLE;
  } // Edge case: block indentation indicator can only have one digit.


  if (indentPerLevel > 9 && needIndentIndicator(string)) {
    return STYLE_DOUBLE;
  } // At this point we know block styles are valid.
  // Prefer literal style unless we want to fold.


  return hasFoldableLine ? STYLE_FOLDED : STYLE_LITERAL;
} // Note: line breaking/folding is implemented for only the folded style.
// NB. We drop the last trailing newline (if any) of a returned block scalar
//  since the dumper adds its own newline. This always works:
//    • No ending newline => unaffected; already using strip "-" chomping.
//    • Ending newline    => removed then restored.
//  Importantly, this keeps the "+" chomp indicator from gaining an extra line.


function writeScalar(state, string, level, iskey) {
  state.dump = function () {
    if (string.length === 0) {
      return "''";
    }

    if (!state.noCompatMode && DEPRECATED_BOOLEANS_SYNTAX.indexOf(string) !== -1) {
      return "'" + string + "'";
    }

    var indent = state.indent * Math.max(1, level); // no 0-indent scalars
    // As indentation gets deeper, let the width decrease monotonically
    // to the lower bound min(state.lineWidth, 40).
    // Note that this implies
    //  state.lineWidth ≤ 40 + state.indent: width is fixed at the lower bound.
    //  state.lineWidth > 40 + state.indent: width decreases until the lower bound.
    // This behaves better than a constant minimum width which disallows narrower options,
    // or an indent threshold which causes the width to suddenly increase.

    var lineWidth = state.lineWidth === -1 ? -1 : Math.max(Math.min(state.lineWidth, 40), state.lineWidth - indent); // Without knowing if keys are implicit/explicit, assume implicit for safety.

    var singleLineOnly = iskey // No block styles in flow mode.
    || state.flowLevel > -1 && level >= state.flowLevel;

    function testAmbiguity(string) {
      return testImplicitResolving(state, string);
    }

    switch (chooseScalarStyle(string, singleLineOnly, state.indent, lineWidth, testAmbiguity)) {
      case STYLE_PLAIN:
        return string;

      case STYLE_SINGLE:
        return "'" + string.replace(/'/g, "''") + "'";

      case STYLE_LITERAL:
        return '|' + blockHeader(string, state.indent) + dropEndingNewline(indentString(string, indent));

      case STYLE_FOLDED:
        return '>' + blockHeader(string, state.indent) + dropEndingNewline(indentString(foldString(string, lineWidth), indent));

      case STYLE_DOUBLE:
        return '"' + escapeString(string, lineWidth) + '"';

      default:
        throw new exception('impossible error: invalid scalar style');
    }
  }();
} // Pre-conditions: string is valid for a block scalar, 1 <= indentPerLevel <= 9.


function blockHeader(string, indentPerLevel) {
  var indentIndicator = needIndentIndicator(string) ? String(indentPerLevel) : ''; // note the special case: the string '\n' counts as a "trailing" empty line.

  var clip = string[string.length - 1] === '\n';
  var keep = clip && (string[string.length - 2] === '\n' || string === '\n');
  var chomp = keep ? '+' : clip ? '' : '-';
  return indentIndicator + chomp + '\n';
} // (See the note for writeScalar.)


function dropEndingNewline(string) {
  return string[string.length - 1] === '\n' ? string.slice(0, -1) : string;
} // Note: a long line without a suitable break point will exceed the width limit.
// Pre-conditions: every char in str isPrintable, str.length > 0, width > 0.


function foldString(string, width) {
  // In folded style, $k$ consecutive newlines output as $k+1$ newlines—
  // unless they're before or after a more-indented line, or at the very
  // beginning or end, in which case $k$ maps to $k$.
  // Therefore, parse each chunk as newline(s) followed by a content line.
  var lineRe = /(\n+)([^\n]*)/g; // first line (possibly an empty line)

  var result = function () {
    var nextLF = string.indexOf('\n');
    nextLF = nextLF !== -1 ? nextLF : string.length;
    lineRe.lastIndex = nextLF;
    return foldLine(string.slice(0, nextLF), width);
  }(); // If we haven't reached the first content line yet, don't add an extra \n.


  var prevMoreIndented = string[0] === '\n' || string[0] === ' ';
  var moreIndented; // rest of the lines

  var match;

  while (match = lineRe.exec(string)) {
    var prefix = match[1],
        line = match[2];
    moreIndented = line[0] === ' ';
    result += prefix + (!prevMoreIndented && !moreIndented && line !== '' ? '\n' : '') + foldLine(line, width);
    prevMoreIndented = moreIndented;
  }

  return result;
} // Greedy line breaking.
// Picks the longest line under the limit each time,
// otherwise settles for the shortest line over the limit.
// NB. More-indented lines *cannot* be folded, as that would add an extra \n.


function foldLine(line, width) {
  if (line === '' || line[0] === ' ') return line; // Since a more-indented line adds a \n, breaks can't be followed by a space.

  var breakRe = / [^ ]/g; // note: the match index will always be <= length-2.

  var match; // start is an inclusive index. end, curr, and next are exclusive.

  var start = 0,
      end,
      curr = 0,
      next = 0;
  var result = ''; // Invariants: 0 <= start <= length-1.
  //   0 <= curr <= next <= max(0, length-2). curr - start <= width.
  // Inside the loop:
  //   A match implies length >= 2, so curr and next are <= length-2.

  while (match = breakRe.exec(line)) {
    next = match.index; // maintain invariant: curr - start <= width

    if (next - start > width) {
      end = curr > start ? curr : next; // derive end <= length-2

      result += '\n' + line.slice(start, end); // skip the space that was output as \n

      start = end + 1; // derive start <= length-1
    }

    curr = next;
  } // By the invariants, start <= length-1, so there is something left over.
  // It is either the whole string or a part starting from non-whitespace.


  result += '\n'; // Insert a break if the remainder is too long and there is a break available.

  if (line.length - start > width && curr > start) {
    result += line.slice(start, curr) + '\n' + line.slice(curr + 1);
  } else {
    result += line.slice(start);
  }

  return result.slice(1); // drop extra \n joiner
} // Escapes a double-quoted string.


function escapeString(string) {
  var result = '';
  var char, nextChar;
  var escapeSeq;

  for (var i = 0; i < string.length; i++) {
    char = string.charCodeAt(i); // Check for surrogate pairs (reference Unicode 3.0 section "3.7 Surrogates").

    if (char >= 0xD800 && char <= 0xDBFF
    /* high surrogate */
    ) {
        nextChar = string.charCodeAt(i + 1);

        if (nextChar >= 0xDC00 && nextChar <= 0xDFFF
        /* low surrogate */
        ) {
            // Combine the surrogate pair and store it escaped.
            result += encodeHex((char - 0xD800) * 0x400 + nextChar - 0xDC00 + 0x10000); // Advance index one extra since we already used that char here.

            i++;
            continue;
          }
      }

    escapeSeq = ESCAPE_SEQUENCES[char];
    result += !escapeSeq && isPrintable(char) ? string[i] : escapeSeq || encodeHex(char);
  }

  return result;
}

function writeFlowSequence(state, level, object) {
  var _result = '',
      _tag = state.tag,
      index,
      length;

  for (index = 0, length = object.length; index < length; index += 1) {
    // Write only valid elements.
    if (writeNode(state, level, object[index], false, false)) {
      if (index !== 0) _result += ',' + (!state.condenseFlow ? ' ' : '');
      _result += state.dump;
    }
  }

  state.tag = _tag;
  state.dump = '[' + _result + ']';
}

function writeBlockSequence(state, level, object, compact) {
  var _result = '',
      _tag = state.tag,
      index,
      length;

  for (index = 0, length = object.length; index < length; index += 1) {
    // Write only valid elements.
    if (writeNode(state, level + 1, object[index], true, true)) {
      if (!compact || index !== 0) {
        _result += generateNextLine(state, level);
      }

      if (state.dump && CHAR_LINE_FEED === state.dump.charCodeAt(0)) {
        _result += '-';
      } else {
        _result += '- ';
      }

      _result += state.dump;
    }
  }

  state.tag = _tag;
  state.dump = _result || '[]'; // Empty sequence if no valid values.
}

function writeFlowMapping(state, level, object) {
  var _result = '',
      _tag = state.tag,
      objectKeyList = Object.keys(object),
      index,
      length,
      objectKey,
      objectValue,
      pairBuffer;

  for (index = 0, length = objectKeyList.length; index < length; index += 1) {
    pairBuffer = state.condenseFlow ? '"' : '';
    if (index !== 0) pairBuffer += ', ';
    objectKey = objectKeyList[index];
    objectValue = object[objectKey];

    if (!writeNode(state, level, objectKey, false, false)) {
      continue; // Skip this pair because of invalid key;
    }

    if (state.dump.length > 1024) pairBuffer += '? ';
    pairBuffer += state.dump + (state.condenseFlow ? '"' : '') + ':' + (state.condenseFlow ? '' : ' ');

    if (!writeNode(state, level, objectValue, false, false)) {
      continue; // Skip this pair because of invalid value.
    }

    pairBuffer += state.dump; // Both key and value are valid.

    _result += pairBuffer;
  }

  state.tag = _tag;
  state.dump = '{' + _result + '}';
}

function writeBlockMapping(state, level, object, compact) {
  var _result = '',
      _tag = state.tag,
      objectKeyList = Object.keys(object),
      index,
      length,
      objectKey,
      objectValue,
      explicitPair,
      pairBuffer; // Allow sorting keys so that the output file is deterministic

  if (state.sortKeys === true) {
    // Default sorting
    objectKeyList.sort();
  } else if (typeof state.sortKeys === 'function') {
    // Custom sort function
    objectKeyList.sort(state.sortKeys);
  } else if (state.sortKeys) {
    // Something is wrong
    throw new exception('sortKeys must be a boolean or a function');
  }

  for (index = 0, length = objectKeyList.length; index < length; index += 1) {
    pairBuffer = '';

    if (!compact || index !== 0) {
      pairBuffer += generateNextLine(state, level);
    }

    objectKey = objectKeyList[index];
    objectValue = object[objectKey];

    if (!writeNode(state, level + 1, objectKey, true, true, true)) {
      continue; // Skip this pair because of invalid key.
    }

    explicitPair = state.tag !== null && state.tag !== '?' || state.dump && state.dump.length > 1024;

    if (explicitPair) {
      if (state.dump && CHAR_LINE_FEED === state.dump.charCodeAt(0)) {
        pairBuffer += '?';
      } else {
        pairBuffer += '? ';
      }
    }

    pairBuffer += state.dump;

    if (explicitPair) {
      pairBuffer += generateNextLine(state, level);
    }

    if (!writeNode(state, level + 1, objectValue, true, explicitPair)) {
      continue; // Skip this pair because of invalid value.
    }

    if (state.dump && CHAR_LINE_FEED === state.dump.charCodeAt(0)) {
      pairBuffer += ':';
    } else {
      pairBuffer += ': ';
    }

    pairBuffer += state.dump; // Both key and value are valid.

    _result += pairBuffer;
  }

  state.tag = _tag;
  state.dump = _result || '{}'; // Empty mapping if no valid pairs.
}

function detectType(state, object, explicit) {
  var _result, typeList, index, length, type, style;

  typeList = explicit ? state.explicitTypes : state.implicitTypes;

  for (index = 0, length = typeList.length; index < length; index += 1) {
    type = typeList[index];

    if ((type.instanceOf || type.predicate) && (!type.instanceOf || typeof object === 'object' && object instanceof type.instanceOf) && (!type.predicate || type.predicate(object))) {
      state.tag = explicit ? type.tag : '?';

      if (type.represent) {
        style = state.styleMap[type.tag] || type.defaultStyle;

        if (_toString$2.call(type.represent) === '[object Function]') {
          _result = type.represent(object, style);
        } else if (_hasOwnProperty$3.call(type.represent, style)) {
          _result = type.represent[style](object, style);
        } else {
          throw new exception('!<' + type.tag + '> tag resolver accepts not "' + style + '" style');
        }

        state.dump = _result;
      }

      return true;
    }
  }

  return false;
} // Serializes `object` and writes it to global `result`.
// Returns true on success, or false on invalid object.
//


function writeNode(state, level, object, block, compact, iskey) {
  state.tag = null;
  state.dump = object;

  if (!detectType(state, object, false)) {
    detectType(state, object, true);
  }

  var type = _toString$2.call(state.dump);

  if (block) {
    block = state.flowLevel < 0 || state.flowLevel > level;
  }

  var objectOrArray = type === '[object Object]' || type === '[object Array]',
      duplicateIndex,
      duplicate;

  if (objectOrArray) {
    duplicateIndex = state.duplicates.indexOf(object);
    duplicate = duplicateIndex !== -1;
  }

  if (state.tag !== null && state.tag !== '?' || duplicate || state.indent !== 2 && level > 0) {
    compact = false;
  }

  if (duplicate && state.usedDuplicates[duplicateIndex]) {
    state.dump = '*ref_' + duplicateIndex;
  } else {
    if (objectOrArray && duplicate && !state.usedDuplicates[duplicateIndex]) {
      state.usedDuplicates[duplicateIndex] = true;
    }

    if (type === '[object Object]') {
      if (block && Object.keys(state.dump).length !== 0) {
        writeBlockMapping(state, level, state.dump, compact);

        if (duplicate) {
          state.dump = '&ref_' + duplicateIndex + state.dump;
        }
      } else {
        writeFlowMapping(state, level, state.dump);

        if (duplicate) {
          state.dump = '&ref_' + duplicateIndex + ' ' + state.dump;
        }
      }
    } else if (type === '[object Array]') {
      var arrayLevel = state.noArrayIndent && level > 0 ? level - 1 : level;

      if (block && state.dump.length !== 0) {
        writeBlockSequence(state, arrayLevel, state.dump, compact);

        if (duplicate) {
          state.dump = '&ref_' + duplicateIndex + state.dump;
        }
      } else {
        writeFlowSequence(state, arrayLevel, state.dump);

        if (duplicate) {
          state.dump = '&ref_' + duplicateIndex + ' ' + state.dump;
        }
      }
    } else if (type === '[object String]') {
      if (state.tag !== '?') {
        writeScalar(state, state.dump, level, iskey);
      }
    } else {
      if (state.skipInvalid) return false;
      throw new exception('unacceptable kind of an object to dump ' + type);
    }

    if (state.tag !== null && state.tag !== '?') {
      state.dump = '!<' + state.tag + '> ' + state.dump;
    }
  }

  return true;
}

function getDuplicateReferences(object, state) {
  var objects = [],
      duplicatesIndexes = [],
      index,
      length;
  inspectNode(object, objects, duplicatesIndexes);

  for (index = 0, length = duplicatesIndexes.length; index < length; index += 1) {
    state.duplicates.push(objects[duplicatesIndexes[index]]);
  }

  state.usedDuplicates = new Array(length);
}

function inspectNode(object, objects, duplicatesIndexes) {
  var objectKeyList, index, length;

  if (object !== null && typeof object === 'object') {
    index = objects.indexOf(object);

    if (index !== -1) {
      if (duplicatesIndexes.indexOf(index) === -1) {
        duplicatesIndexes.push(index);
      }
    } else {
      objects.push(object);

      if (Array.isArray(object)) {
        for (index = 0, length = object.length; index < length; index += 1) {
          inspectNode(object[index], objects, duplicatesIndexes);
        }
      } else {
        objectKeyList = Object.keys(object);

        for (index = 0, length = objectKeyList.length; index < length; index += 1) {
          inspectNode(object[objectKeyList[index]], objects, duplicatesIndexes);
        }
      }
    }
  }
}

function dump$1(input, options) {
  options = options || {};
  var state = new State$1(options);
  if (!state.noRefs) getDuplicateReferences(input, state);
  if (writeNode(state, 0, input, true, true)) return state.dump + '\n';
  return '';
}

function safeDump$1(input, options) {
  return dump$1(input, common.extend({
    schema: default_safe
  }, options));
}

var dump_1 = dump$1;
var safeDump_1 = safeDump$1;
var dumper = {
  dump: dump_1,
  safeDump: safeDump_1
};

function deprecated(name) {
  return function () {
    throw new Error('Function ' + name + ' is deprecated and cannot be used.');
  };
}

var Type = type;
var Schema = schema;
var FAILSAFE_SCHEMA = failsafe;
var JSON_SCHEMA = json;
var CORE_SCHEMA = core;
var DEFAULT_SAFE_SCHEMA = default_safe;
var DEFAULT_FULL_SCHEMA = default_full;
var load = loader.load;
var loadAll = loader.loadAll;
var safeLoad = loader.safeLoad;
var safeLoadAll = loader.safeLoadAll;
var dump = dumper.dump;
var safeDump = dumper.safeDump;
var YAMLException = exception; // Deprecated schema names from JS-YAML 2.0.x

var MINIMAL_SCHEMA = failsafe;
var SAFE_SCHEMA = default_safe;
var DEFAULT_SCHEMA = default_full; // Deprecated functions from JS-YAML 1.x.x

var scan = deprecated('scan');
var parse = deprecated('parse');
var compose = deprecated('compose');
var addConstructor = deprecated('addConstructor');
var jsYaml$2 = {
  Type: Type,
  Schema: Schema,
  FAILSAFE_SCHEMA: FAILSAFE_SCHEMA,
  JSON_SCHEMA: JSON_SCHEMA,
  CORE_SCHEMA: CORE_SCHEMA,
  DEFAULT_SAFE_SCHEMA: DEFAULT_SAFE_SCHEMA,
  DEFAULT_FULL_SCHEMA: DEFAULT_FULL_SCHEMA,
  load: load,
  loadAll: loadAll,
  safeLoad: safeLoad,
  safeLoadAll: safeLoadAll,
  dump: dump,
  safeDump: safeDump,
  YAMLException: YAMLException,
  MINIMAL_SCHEMA: MINIMAL_SCHEMA,
  SAFE_SCHEMA: SAFE_SCHEMA,
  DEFAULT_SCHEMA: DEFAULT_SCHEMA,
  scan: scan,
  parse: parse,
  compose: compose,
  addConstructor: addConstructor
};

var jsYaml = jsYaml$2;

var resolveFrom_1 = createCommonjsModule(function (module) {
  'use strict';

  var resolveFrom = function resolveFrom(fromDir, moduleId, silent) {
    if (typeof fromDir !== 'string') {
      throw new TypeError(`Expected \`fromDir\` to be of type \`string\`, got \`${typeof fromDir}\``);
    }

    if (typeof moduleId !== 'string') {
      throw new TypeError(`Expected \`moduleId\` to be of type \`string\`, got \`${typeof moduleId}\``);
    }

    fromDir = path.resolve(fromDir);
    var fromFile = path.join(fromDir, 'noop.js');

    var resolveFileName = function resolveFileName() {
      return module$1._resolveFilename(moduleId, {
        id: fromFile,
        filename: fromFile,
        paths: module$1._nodeModulePaths(fromDir)
      });
    };

    if (silent) {
      try {
        return resolveFileName();
      } catch (err) {
        return null;
      }
    }

    return resolveFileName();
  };

  module.exports = function (fromDir, moduleId) {
    return resolveFrom(fromDir, moduleId);
  };

  module.exports.silent = function (fromDir, moduleId) {
    return resolveFrom(fromDir, moduleId, true);
  };
});

var callsites = createCommonjsModule(function (module) {
  'use strict';

  module.exports = function () {
    var _ = Error.prepareStackTrace;

    Error.prepareStackTrace = function (_, stack) {
      return stack;
    };

    var stack = new Error().stack.slice(1);
    Error.prepareStackTrace = _;
    return stack;
  };
});

var callerCallsite = createCommonjsModule(function (module) {
  'use strict';

  module.exports = function () {
    var c = callsites();
    var caller;

    for (var i = 0; i < c.length; i++) {
      var hasReceiver = c[i].getTypeName() !== null;

      if (hasReceiver) {
        caller = i;
        break;
      }
    }

    return c[caller];
  };
});

var callerPath = function callerPath() {
  return callerCallsite().getFileName();
};

var importFresh = createCommonjsModule(function (module) {
  'use strict';

  module.exports = function (moduleId) {
    if (typeof moduleId !== 'string') {
      throw new TypeError('Expected a string');
    }

    var filePath = resolveFrom_1(path.dirname(callerPath()), moduleId); // Delete itself from module parent

    if (require.cache[filePath] && require.cache[filePath].parent) {
      var i = require.cache[filePath].parent.children.length;

      while (i--) {
        if (require.cache[filePath].parent.children[i].id === filePath) {
          require.cache[filePath].parent.children.splice(i, 1);
        }
      }
    } // Delete module from cache


    delete require.cache[filePath]; // Return fresh module

    return require(filePath);
  };
});

function loadJs(filepath) {
  var result = importFresh(filepath);
  return result;
}

function loadJson(filepath, content) {
  try {
    return parseJson(content);
  } catch (err) {
    err.message = `JSON Error in ${filepath}:\n${err.message}`;
    throw err;
  }
}

function loadYaml(filepath, content) {
  return jsYaml.safeLoad(content, {
    filename: filepath
  });
}

var loaders = {
  loadJs,
  loadJson,
  loadYaml
};

function readFile(filepath, options) {
  options = options || {};
  var throwNotFound = options.throwNotFound || false;
  return new Promise(function (resolve, reject) {
    fs.readFile(filepath, 'utf8', function (err, content) {
      if (err && err.code === 'ENOENT' && !throwNotFound) {
        return resolve(null);
      }

      if (err) return reject(err);
      resolve(content);
    });
  });
}

readFile.sync = function readFileSync(filepath, options) {
  options = options || {};
  var throwNotFound = options.throwNotFound || false;

  try {
    return fs.readFileSync(filepath, 'utf8');
  } catch (err) {
    if (err.code === 'ENOENT' && !throwNotFound) {
      return null;
    }

    throw err;
  }
};

var readFile_1 = readFile;

//      
function cacheWrapper(cache, key, fn) {
  if (!cache) {
    return fn();
  }

  var cached = cache.get(key);

  if (cached !== undefined) {
    return cached;
  }

  var result = fn();
  cache.set(key, result);
  return result;
}

var cacheWrapper_1 = cacheWrapper;

/**
 * async
 */


function isDirectory(filepath, cb) {
  if (typeof cb !== 'function') {
    throw new Error('expected a callback function');
  }

  if (typeof filepath !== 'string') {
    cb(new Error('expected filepath to be a string'));
    return;
  }

  fs.stat(filepath, function (err, stats) {
    if (err) {
      if (err.code === 'ENOENT') {
        cb(null, false);
        return;
      }

      cb(err);
      return;
    }

    cb(null, stats.isDirectory());
  });
}
/**
 * sync
 */


isDirectory.sync = function isDirectorySync(filepath) {
  if (typeof filepath !== 'string') {
    throw new Error('expected filepath to be a string');
  }

  try {
    var stat = fs.statSync(filepath);
    return stat.isDirectory();
  } catch (err) {
    if (err.code === 'ENOENT') {
      return false;
    } else {
      throw err;
    }
  }

  return false;
};
/**
 * Expose `isDirectory`
 */


var isDirectory_1 = isDirectory;

function getDirectory(filepath) {
  return new Promise(function (resolve, reject) {
    return isDirectory_1(filepath, function (err, filepathIsDirectory) {
      if (err) {
        return reject(err);
      }

      return resolve(filepathIsDirectory ? filepath : path.dirname(filepath));
    });
  });
}

getDirectory.sync = function getDirectorySync(filepath) {
  return isDirectory_1.sync(filepath) ? filepath : path.dirname(filepath);
};

var getDirectory_1 = getDirectory;

var MODE_SYNC = 'sync'; // An object value represents a config object.
// null represents that the loader did not find anything relevant.
// undefined represents that the loader found something relevant
// but it was empty.

var Explorer =
/*#__PURE__*/
function () {
  function Explorer(options) {
    _classCallCheck(this, Explorer);

    this.loadCache = options.cache ? new Map() : null;
    this.loadSyncCache = options.cache ? new Map() : null;
    this.searchCache = options.cache ? new Map() : null;
    this.searchSyncCache = options.cache ? new Map() : null;
    this.config = options;
    this.validateConfig();
  }

  _createClass(Explorer, [{
    key: "clearLoadCache",
    value: function clearLoadCache() {
      if (this.loadCache) {
        this.loadCache.clear();
      }

      if (this.loadSyncCache) {
        this.loadSyncCache.clear();
      }
    }
  }, {
    key: "clearSearchCache",
    value: function clearSearchCache() {
      if (this.searchCache) {
        this.searchCache.clear();
      }

      if (this.searchSyncCache) {
        this.searchSyncCache.clear();
      }
    }
  }, {
    key: "clearCaches",
    value: function clearCaches() {
      this.clearLoadCache();
      this.clearSearchCache();
    }
  }, {
    key: "validateConfig",
    value: function validateConfig() {
      var config = this.config;
      config.searchPlaces.forEach(function (place) {
        var loaderKey = path.extname(place) || 'noExt';
        var loader = config.loaders[loaderKey];

        if (!loader) {
          throw new Error(`No loader specified for ${getExtensionDescription(place)}, so searchPlaces item "${place}" is invalid`);
        }
      });
    }
  }, {
    key: "search",
    value: function search(searchFrom) {
      var _this = this;

      searchFrom = searchFrom || process.cwd();
      return getDirectory_1(searchFrom).then(function (dir) {
        return _this.searchFromDirectory(dir);
      });
    }
  }, {
    key: "searchFromDirectory",
    value: function searchFromDirectory(dir) {
      var _this2 = this;

      var absoluteDir = path.resolve(process.cwd(), dir);

      var run = function run() {
        return _this2.searchDirectory(absoluteDir).then(function (result) {
          var nextDir = _this2.nextDirectoryToSearch(absoluteDir, result);

          if (nextDir) {
            return _this2.searchFromDirectory(nextDir);
          }

          return _this2.config.transform(result);
        });
      };

      if (this.searchCache) {
        return cacheWrapper_1(this.searchCache, absoluteDir, run);
      }

      return run();
    }
  }, {
    key: "searchSync",
    value: function searchSync(searchFrom) {
      searchFrom = searchFrom || process.cwd();
      var dir = getDirectory_1.sync(searchFrom);
      return this.searchFromDirectorySync(dir);
    }
  }, {
    key: "searchFromDirectorySync",
    value: function searchFromDirectorySync(dir) {
      var _this3 = this;

      var absoluteDir = path.resolve(process.cwd(), dir);

      var run = function run() {
        var result = _this3.searchDirectorySync(absoluteDir);

        var nextDir = _this3.nextDirectoryToSearch(absoluteDir, result);

        if (nextDir) {
          return _this3.searchFromDirectorySync(nextDir);
        }

        return _this3.config.transform(result);
      };

      if (this.searchSyncCache) {
        return cacheWrapper_1(this.searchSyncCache, absoluteDir, run);
      }

      return run();
    }
  }, {
    key: "searchDirectory",
    value: function searchDirectory(dir) {
      var _this4 = this;

      return this.config.searchPlaces.reduce(function (prevResultPromise, place) {
        return prevResultPromise.then(function (prevResult) {
          if (_this4.shouldSearchStopWithResult(prevResult)) {
            return prevResult;
          }

          return _this4.loadSearchPlace(dir, place);
        });
      }, Promise.resolve(null));
    }
  }, {
    key: "searchDirectorySync",
    value: function searchDirectorySync(dir) {
      var result = null;
      var _iteratorNormalCompletion = true;
      var _didIteratorError = false;
      var _iteratorError = undefined;

      try {
        for (var _iterator = this.config.searchPlaces[Symbol.iterator](), _step; !(_iteratorNormalCompletion = (_step = _iterator.next()).done); _iteratorNormalCompletion = true) {
          var place = _step.value;
          result = this.loadSearchPlaceSync(dir, place);
          if (this.shouldSearchStopWithResult(result)) break;
        }
      } catch (err) {
        _didIteratorError = true;
        _iteratorError = err;
      } finally {
        try {
          if (!_iteratorNormalCompletion && _iterator.return != null) {
            _iterator.return();
          }
        } finally {
          if (_didIteratorError) {
            throw _iteratorError;
          }
        }
      }

      return result;
    }
  }, {
    key: "shouldSearchStopWithResult",
    value: function shouldSearchStopWithResult(result) {
      if (result === null) return false;
      if (result.isEmpty && this.config.ignoreEmptySearchPlaces) return false;
      return true;
    }
  }, {
    key: "loadSearchPlace",
    value: function loadSearchPlace(dir, place) {
      var _this5 = this;

      var filepath = path.join(dir, place);
      return readFile_1(filepath).then(function (content) {
        return _this5.createCosmiconfigResult(filepath, content);
      });
    }
  }, {
    key: "loadSearchPlaceSync",
    value: function loadSearchPlaceSync(dir, place) {
      var filepath = path.join(dir, place);
      var content = readFile_1.sync(filepath);
      return this.createCosmiconfigResultSync(filepath, content);
    }
  }, {
    key: "nextDirectoryToSearch",
    value: function nextDirectoryToSearch(currentDir, currentResult) {
      if (this.shouldSearchStopWithResult(currentResult)) {
        return null;
      }

      var nextDir = nextDirUp(currentDir);

      if (nextDir === currentDir || currentDir === this.config.stopDir) {
        return null;
      }

      return nextDir;
    }
  }, {
    key: "loadPackageProp",
    value: function loadPackageProp(filepath, content) {
      var parsedContent = loaders.loadJson(filepath, content);
      var packagePropValue = parsedContent[this.config.packageProp];
      return packagePropValue || null;
    }
  }, {
    key: "getLoaderEntryForFile",
    value: function getLoaderEntryForFile(filepath) {
      if (path.basename(filepath) === 'package.json') {
        var loader = this.loadPackageProp.bind(this);
        return {
          sync: loader,
          async: loader
        };
      }

      var loaderKey = path.extname(filepath) || 'noExt';
      return this.config.loaders[loaderKey] || {};
    }
  }, {
    key: "getSyncLoaderForFile",
    value: function getSyncLoaderForFile(filepath) {
      var entry = this.getLoaderEntryForFile(filepath);

      if (!entry.sync) {
        throw new Error(`No sync loader specified for ${getExtensionDescription(filepath)}`);
      }

      return entry.sync;
    }
  }, {
    key: "getAsyncLoaderForFile",
    value: function getAsyncLoaderForFile(filepath) {
      var entry = this.getLoaderEntryForFile(filepath);
      var loader = entry.async || entry.sync;

      if (!loader) {
        throw new Error(`No async loader specified for ${getExtensionDescription(filepath)}`);
      }

      return loader;
    }
  }, {
    key: "loadFileContent",
    value: function loadFileContent(mode, filepath, content) {
      if (content === null) {
        return null;
      }

      if (content.trim() === '') {
        return undefined;
      }

      var loader = mode === MODE_SYNC ? this.getSyncLoaderForFile(filepath) : this.getAsyncLoaderForFile(filepath);
      return loader(filepath, content);
    }
  }, {
    key: "loadedContentToCosmiconfigResult",
    value: function loadedContentToCosmiconfigResult(filepath, loadedContent) {
      if (loadedContent === null) {
        return null;
      }

      if (loadedContent === undefined) {
        return {
          filepath,
          config: undefined,
          isEmpty: true
        };
      }

      return {
        config: loadedContent,
        filepath
      };
    }
  }, {
    key: "createCosmiconfigResult",
    value: function createCosmiconfigResult(filepath, content) {
      var _this6 = this;

      return Promise.resolve().then(function () {
        return _this6.loadFileContent('async', filepath, content);
      }).then(function (loaderResult) {
        return _this6.loadedContentToCosmiconfigResult(filepath, loaderResult);
      });
    }
  }, {
    key: "createCosmiconfigResultSync",
    value: function createCosmiconfigResultSync(filepath, content) {
      var loaderResult = this.loadFileContent('sync', filepath, content);
      return this.loadedContentToCosmiconfigResult(filepath, loaderResult);
    }
  }, {
    key: "validateFilePath",
    value: function validateFilePath(filepath) {
      if (!filepath) {
        throw new Error('load and loadSync must pass a non-empty string');
      }
    }
  }, {
    key: "load",
    value: function load(filepath) {
      var _this7 = this;

      return Promise.resolve().then(function () {
        _this7.validateFilePath(filepath);

        var absoluteFilePath = path.resolve(process.cwd(), filepath);
        return cacheWrapper_1(_this7.loadCache, absoluteFilePath, function () {
          return readFile_1(absoluteFilePath, {
            throwNotFound: true
          }).then(function (content) {
            return _this7.createCosmiconfigResult(absoluteFilePath, content);
          }).then(_this7.config.transform);
        });
      });
    }
  }, {
    key: "loadSync",
    value: function loadSync(filepath) {
      var _this8 = this;

      this.validateFilePath(filepath);
      var absoluteFilePath = path.resolve(process.cwd(), filepath);
      return cacheWrapper_1(this.loadSyncCache, absoluteFilePath, function () {
        var content = readFile_1.sync(absoluteFilePath, {
          throwNotFound: true
        });

        var result = _this8.createCosmiconfigResultSync(absoluteFilePath, content);

        return _this8.config.transform(result);
      });
    }
  }]);

  return Explorer;
}();

var createExplorer = function createExplorer(options) {
  var explorer = new Explorer(options);
  return {
    search: explorer.search.bind(explorer),
    searchSync: explorer.searchSync.bind(explorer),
    load: explorer.load.bind(explorer),
    loadSync: explorer.loadSync.bind(explorer),
    clearLoadCache: explorer.clearLoadCache.bind(explorer),
    clearSearchCache: explorer.clearSearchCache.bind(explorer),
    clearCaches: explorer.clearCaches.bind(explorer)
  };
};

function nextDirUp(dir) {
  return path.dirname(dir);
}

function getExtensionDescription(filepath) {
  var ext = path.extname(filepath);
  return ext ? `extension "${ext}"` : 'files without extensions';
}

var dist = cosmiconfig;

function cosmiconfig(moduleName, options) {
  options = options || {};
  var defaults = {
    packageProp: moduleName,
    searchPlaces: ['package.json', `.${moduleName}rc`, `.${moduleName}rc.json`, `.${moduleName}rc.yaml`, `.${moduleName}rc.yml`, `.${moduleName}rc.js`, `${moduleName}.config.js`],
    ignoreEmptySearchPlaces: true,
    stopDir: os.homedir(),
    cache: true,
    transform: identity
  };
  var normalizedOptions = Object.assign({}, defaults, options, {
    loaders: normalizeLoaders(options.loaders)
  });
  return createExplorer(normalizedOptions);
}

cosmiconfig.loadJs = loaders.loadJs;
cosmiconfig.loadJson = loaders.loadJson;
cosmiconfig.loadYaml = loaders.loadYaml;

function normalizeLoaders(rawLoaders) {
  var defaults = {
    '.js': {
      sync: loaders.loadJs,
      async: loaders.loadJs
    },
    '.json': {
      sync: loaders.loadJson,
      async: loaders.loadJson
    },
    '.yaml': {
      sync: loaders.loadYaml,
      async: loaders.loadYaml
    },
    '.yml': {
      sync: loaders.loadYaml,
      async: loaders.loadYaml
    },
    noExt: {
      sync: loaders.loadYaml,
      async: loaders.loadYaml
    }
  };

  if (!rawLoaders) {
    return defaults;
  }

  return Object.keys(rawLoaders).reduce(function (result, ext) {
    var entry = rawLoaders && rawLoaders[ext];

    if (typeof entry === 'function') {
      result[ext] = {
        sync: entry,
        async: entry
      };
    } else {
      result[ext] = entry;
    }

    return result;
  }, defaults);
}

function identity(x) {
  return x;
}

var findParentDir$1 = createCommonjsModule(function (module, exports) {
  'use strict';

  var exists = fs.exists || path.exists,
      existsSync = fs.existsSync || path.existsSync;

  function splitPath(path$$2) {
    var parts = path$$2.split(/(\/|\\)/);
    if (!parts.length) return parts; // when path starts with a slash, the first part is empty string

    return !parts[0].length ? parts.slice(1) : parts;
  }

  exports = module.exports = function (currentFullPath, clue, cb) {
    function testDir(parts) {
      if (parts.length === 0) return cb(null, null);
      var p = parts.join('');
      exists(path.join(p, clue), function (itdoes) {
        if (itdoes) return cb(null, p);
        testDir(parts.slice(0, -1));
      });
    }

    testDir(splitPath(currentFullPath));
  };

  exports.sync = function (currentFullPath, clue) {
    function testDir(parts) {
      if (parts.length === 0) return null;
      var p = parts.join('');
      var itdoes = existsSync(path.join(p, clue));
      return itdoes ? p : testDir(parts.slice(0, -1));
    }

    return testDir(splitPath(currentFullPath));
  };
});

var bufferStream = createCommonjsModule(function (module) {
  'use strict';

  var PassThrough = stream.PassThrough;

  module.exports = function (opts) {
    opts = Object.assign({}, opts);
    var array = opts.array;
    var encoding = opts.encoding;
    var buffer = encoding === 'buffer';
    var objectMode = false;

    if (array) {
      objectMode = !(encoding || buffer);
    } else {
      encoding = encoding || 'utf8';
    }

    if (buffer) {
      encoding = null;
    }

    var len = 0;
    var ret = [];
    var stream$$1 = new PassThrough({
      objectMode
    });

    if (encoding) {
      stream$$1.setEncoding(encoding);
    }

    stream$$1.on('data', function (chunk) {
      ret.push(chunk);

      if (objectMode) {
        len = ret.length;
      } else {
        len += chunk.length;
      }
    });

    stream$$1.getBufferedValue = function () {
      if (array) {
        return ret;
      }

      return buffer ? Buffer.concat(ret, len) : ret.join('');
    };

    stream$$1.getBufferedLength = function () {
      return len;
    };

    return stream$$1;
  };
});

function getStream(inputStream, opts) {
  if (!inputStream) {
    return Promise.reject(new Error('Expected a stream'));
  }

  opts = Object.assign({
    maxBuffer: Infinity
  }, opts);
  var maxBuffer = opts.maxBuffer;
  var stream$$1;
  var clean;
  var p = new Promise(function (resolve, reject) {
    var error = function error(err) {
      if (err) {
        // null check
        err.bufferedData = stream$$1.getBufferedValue();
      }

      reject(err);
    };

    stream$$1 = bufferStream(opts);
    inputStream.once('error', error);
    inputStream.pipe(stream$$1);
    stream$$1.on('data', function () {
      if (stream$$1.getBufferedLength() > maxBuffer) {
        reject(new Error('maxBuffer exceeded'));
      }
    });
    stream$$1.once('error', error);
    stream$$1.on('end', resolve);

    clean = function clean() {
      // some streams doesn't implement the `stream.Readable` interface correctly
      if (inputStream.unpipe) {
        inputStream.unpipe(stream$$1);
      }
    };
  });
  p.then(clean, clean);
  return p.then(function () {
    return stream$$1.getBufferedValue();
  });
}

var getStream_1 = getStream;

var buffer = function buffer(stream$$1, opts) {
  return getStream(stream$$1, Object.assign({}, opts, {
    encoding: 'buffer'
  }));
};

var array = function array(stream$$1, opts) {
  return getStream(stream$$1, Object.assign({}, opts, {
    array: true
  }));
};

getStream_1.buffer = buffer;
getStream_1.array = array;

var vendors = [{
  "name": "AppVeyor",
  "constant": "APPVEYOR",
  "env": "APPVEYOR",
  "pr": "APPVEYOR_PULL_REQUEST_NUMBER"
}, {
  "name": "Azure Pipelines",
  "constant": "AZURE_PIPELINES",
  "env": "SYSTEM_TEAMFOUNDATIONCOLLECTIONURI",
  "pr": "SYSTEM_PULLREQUEST_PULLREQUESTID"
}, {
  "name": "Bamboo",
  "constant": "BAMBOO",
  "env": "bamboo_planKey"
}, {
  "name": "Bitbucket Pipelines",
  "constant": "BITBUCKET",
  "env": "BITBUCKET_COMMIT",
  "pr": "BITBUCKET_PR_ID"
}, {
  "name": "Bitrise",
  "constant": "BITRISE",
  "env": "BITRISE_IO",
  "pr": "BITRISE_PULL_REQUEST"
}, {
  "name": "Buddy",
  "constant": "BUDDY",
  "env": "BUDDY_WORKSPACE_ID",
  "pr": "BUDDY_EXECUTION_PULL_REQUEST_ID"
}, {
  "name": "Buildkite",
  "constant": "BUILDKITE",
  "env": "BUILDKITE",
  "pr": {
    "env": "BUILDKITE_PULL_REQUEST",
    "ne": "false"
  }
}, {
  "name": "CircleCI",
  "constant": "CIRCLE",
  "env": "CIRCLECI",
  "pr": "CIRCLE_PULL_REQUEST"
}, {
  "name": "Cirrus CI",
  "constant": "CIRRUS",
  "env": "CIRRUS_CI",
  "pr": "CIRRUS_PR"
}, {
  "name": "AWS CodeBuild",
  "constant": "CODEBUILD",
  "env": "CODEBUILD_BUILD_ARN"
}, {
  "name": "Codeship",
  "constant": "CODESHIP",
  "env": {
    "CI_NAME": "codeship"
  }
}, {
  "name": "Drone",
  "constant": "DRONE",
  "env": "DRONE",
  "pr": {
    "DRONE_BUILD_EVENT": "pull_request"
  }
}, {
  "name": "dsari",
  "constant": "DSARI",
  "env": "DSARI"
}, {
  "name": "GitLab CI",
  "constant": "GITLAB",
  "env": "GITLAB_CI"
}, {
  "name": "GoCD",
  "constant": "GOCD",
  "env": "GO_PIPELINE_LABEL"
}, {
  "name": "Hudson",
  "constant": "HUDSON",
  "env": "HUDSON_URL"
}, {
  "name": "Jenkins",
  "constant": "JENKINS",
  "env": ["JENKINS_URL", "BUILD_ID"],
  "pr": {
    "any": ["ghprbPullId", "CHANGE_ID"]
  }
}, {
  "name": "Magnum CI",
  "constant": "MAGNUM",
  "env": "MAGNUM"
}, {
  "name": "Netlify CI",
  "constant": "NETLIFY",
  "env": "NETLIFY_BUILD_BASE",
  "pr": {
    "env": "PULL_REQUEST",
    "ne": "false"
  }
}, {
  "name": "Sail CI",
  "constant": "SAIL",
  "env": "SAILCI",
  "pr": "SAIL_PULL_REQUEST_NUMBER"
}, {
  "name": "Semaphore",
  "constant": "SEMAPHORE",
  "env": "SEMAPHORE",
  "pr": "PULL_REQUEST_NUMBER"
}, {
  "name": "Shippable",
  "constant": "SHIPPABLE",
  "env": "SHIPPABLE",
  "pr": {
    "IS_PULL_REQUEST": "true"
  }
}, {
  "name": "Solano CI",
  "constant": "SOLANO",
  "env": "TDDIUM",
  "pr": "TDDIUM_PR_ID"
}, {
  "name": "Strider CD",
  "constant": "STRIDER",
  "env": "STRIDER"
}, {
  "name": "TaskCluster",
  "constant": "TASKCLUSTER",
  "env": ["TASK_ID", "RUN_ID"]
}, {
  "name": "TeamCity",
  "constant": "TEAMCITY",
  "env": "TEAMCITY_VERSION"
}, {
  "name": "Travis CI",
  "constant": "TRAVIS",
  "env": "TRAVIS",
  "pr": {
    "env": "TRAVIS_PULL_REQUEST",
    "ne": "false"
  }
}];

var vendors$1 = Object.freeze({
	default: vendors
});

var vendors$2 = ( vendors$1 && vendors ) || vendors$1;

var ciInfo = createCommonjsModule(function (module, exports) {
  'use strict';

  var env = process.env; // Used for testing only

  Object.defineProperty(exports, '_vendors', {
    value: vendors$2.map(function (v) {
      return v.constant;
    })
  });
  exports.name = null;
  exports.isPR = null;
  vendors$2.forEach(function (vendor) {
    var envs = Array.isArray(vendor.env) ? vendor.env : [vendor.env];
    var isCI = envs.every(function (obj) {
      return checkEnv(obj);
    });
    exports[vendor.constant] = isCI;

    if (isCI) {
      exports.name = vendor.name;

      switch (typeof vendor.pr) {
        case 'string':
          // "pr": "CIRRUS_PR"
          exports.isPR = !!env[vendor.pr];
          break;

        case 'object':
          if ('env' in vendor.pr) {
            // "pr": { "env": "BUILDKITE_PULL_REQUEST", "ne": "false" }
            exports.isPR = vendor.pr.env in env && env[vendor.pr.env] !== vendor.pr.ne;
          } else if ('any' in vendor.pr) {
            // "pr": { "any": ["ghprbPullId", "CHANGE_ID"] }
            exports.isPR = vendor.pr.any.some(function (key) {
              return !!env[key];
            });
          } else {
            // "pr": { "DRONE_BUILD_EVENT": "pull_request" }
            exports.isPR = checkEnv(vendor.pr);
          }

          break;

        default:
          // PR detection not supported for this vendor
          exports.isPR = null;
      }
    }
  });
  exports.isCI = !!(env.CI || // Travis CI, CircleCI, Cirrus CI, Gitlab CI, Appveyor, CodeShip, dsari
  env.CONTINUOUS_INTEGRATION || // Travis CI, Cirrus CI
  env.BUILD_NUMBER || // Jenkins, TeamCity
  env.RUN_ID || // TaskCluster, dsari
  exports.name || false);

  function checkEnv(obj) {
    if (typeof obj === 'string') return !!env[obj];
    return Object.keys(obj).every(function (k) {
      return env[k] === obj[k];
    });
  }
});

var isCi = ciInfo.isCI;

var findParentDir = findParentDir$1.sync;
var thirdParty = {
  cosmiconfig: dist,
  findParentDir,
  getStream: getStream_1,
  isCI:
  /* istanbul ignore next */
  function isCI() {
    return isCi;
  }
};

module.exports = thirdParty;