@ramda/uniqby/uniqBy.js

R.uniqBy exported as a module

//  Ramda v0.26.1
//  https://github.com/ramda/ramda
//  (c) 2013-2019 Scott Sauyet, Michael Hurley, and David Chambers
//  Ramda may be freely distributed under the MIT license.

(function (global, factory) {
  typeof exports === 'object' && typeof module !== 'undefined' ? factory(exports) :
  typeof define === 'function' && define.amd ? define(['exports'], factory) :
  (factory((global.R = {})));
}(this, (function (exports) { 'use strict';

  function _isPlaceholder(a) {
    return a != null &&
           typeof a === 'object' &&
           a['@@functional/placeholder'] === true;
  }

  /**
   * Optimized internal one-arity curry function.
   *
   * @private
   * @category Function
   * @param {Function} fn The function to curry.
   * @return {Function} The curried function.
   */
  function _curry1(fn) {
    return function f1(a) {
      if (arguments.length === 0 || _isPlaceholder(a)) {
        return f1;
      } else {
        return fn.apply(this, arguments);
      }
    };
  }

  /**
   * Optimized internal two-arity curry function.
   *
   * @private
   * @category Function
   * @param {Function} fn The function to curry.
   * @return {Function} The curried function.
   */
  function _curry2(fn) {
    return function f2(a, b) {
      switch (arguments.length) {
        case 0:
          return f2;
        case 1:
          return _isPlaceholder(a)
            ? f2
            : _curry1(function(_b) { return fn(a, _b); });
        default:
          return _isPlaceholder(a) && _isPlaceholder(b)
            ? f2
            : _isPlaceholder(a)
              ? _curry1(function(_a) { return fn(_a, b); })
              : _isPlaceholder(b)
                ? _curry1(function(_b) { return fn(a, _b); })
                : fn(a, b);
      }
    };
  }

  function _arrayFromIterator(iter) {
    var list = [];
    var next;
    while (!(next = iter.next()).done) {
      list.push(next.value);
    }
    return list;
  }

  function _includesWith(pred, x, list) {
    var idx = 0;
    var len = list.length;

    while (idx < len) {
      if (pred(x, list[idx])) {
        return true;
      }
      idx += 1;
    }
    return false;
  }

  function _functionName(f) {
    // String(x => x) evaluates to "x => x", so the pattern may not match.
    var match = String(f).match(/^function (\w*)/);
    return match == null ? '' : match[1];
  }

  function _has(prop, obj) {
    return Object.prototype.hasOwnProperty.call(obj, prop);
  }

  // Based on https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/is
  function _objectIs(a, b) {
    // SameValue algorithm
    if (a === b) { // Steps 1-5, 7-10
      // Steps 6.b-6.e: +0 != -0
      return a !== 0 || 1 / a === 1 / b;
    } else {
      // Step 6.a: NaN == NaN
      return a !== a && b !== b;
    }
  }

  var _objectIs$1 = typeof Object.is === 'function' ? Object.is : _objectIs;

  var toString = Object.prototype.toString;
  var _isArguments = (function() {
    return toString.call(arguments) === '[object Arguments]' ?
      function _isArguments(x) { return toString.call(x) === '[object Arguments]'; } :
      function _isArguments(x) { return _has('callee', x); };
  }());

  // cover IE < 9 keys issues
  var hasEnumBug = !({toString: null}).propertyIsEnumerable('toString');
  var nonEnumerableProps = [
    'constructor', 'valueOf', 'isPrototypeOf', 'toString',
    'propertyIsEnumerable', 'hasOwnProperty', 'toLocaleString'
  ];
  // Safari bug
  var hasArgsEnumBug = (function() {
    return arguments.propertyIsEnumerable('length');
  }());

  var contains = function contains(list, item) {
    var idx = 0;
    while (idx < list.length) {
      if (list[idx] === item) {
        return true;
      }
      idx += 1;
    }
    return false;
  };

  /**
   * Returns a list containing the names of all the enumerable own properties of
   * the supplied object.
   * Note that the order of the output array is not guaranteed to be consistent
   * across different JS platforms.
   *
   * @func
   * @memberOf R
   * @since v0.1.0
   * @category Object
   * @sig {k: v} -> [k]
   * @param {Object} obj The object to extract properties from
   * @return {Array} An array of the object's own properties.
   * @see R.keysIn, R.values
   * @example
   *
   *      R.keys({a: 1, b: 2, c: 3}); //=> ['a', 'b', 'c']
   */
  var keys = typeof Object.keys === 'function' && !hasArgsEnumBug ?
    _curry1(function keys(obj) {
      return Object(obj) !== obj ? [] : Object.keys(obj);
    }) :
    _curry1(function keys(obj) {
      if (Object(obj) !== obj) {
        return [];
      }
      var prop, nIdx;
      var ks = [];
      var checkArgsLength = hasArgsEnumBug && _isArguments(obj);
      for (prop in obj) {
        if (_has(prop, obj) && (!checkArgsLength || prop !== 'length')) {
          ks[ks.length] = prop;
        }
      }
      if (hasEnumBug) {
        nIdx = nonEnumerableProps.length - 1;
        while (nIdx >= 0) {
          prop = nonEnumerableProps[nIdx];
          if (_has(prop, obj) && !contains(ks, prop)) {
            ks[ks.length] = prop;
          }
          nIdx -= 1;
        }
      }
      return ks;
    });

  /**
   * Gives a single-word string description of the (native) type of a value,
   * returning such answers as 'Object', 'Number', 'Array', or 'Null'. Does not
   * attempt to distinguish user Object types any further, reporting them all as
   * 'Object'.
   *
   * @func
   * @memberOf R
   * @since v0.8.0
   * @category Type
   * @sig (* -> {*}) -> String
   * @param {*} val The value to test
   * @return {String}
   * @example
   *
   *      R.type({}); //=> "Object"
   *      R.type(1); //=> "Number"
   *      R.type(false); //=> "Boolean"
   *      R.type('s'); //=> "String"
   *      R.type(null); //=> "Null"
   *      R.type([]); //=> "Array"
   *      R.type(/[A-z]/); //=> "RegExp"
   *      R.type(() => {}); //=> "Function"
   *      R.type(undefined); //=> "Undefined"
   */
  var type = _curry1(function type(val) {
    return val === null
      ? 'Null'
      : val === undefined
        ? 'Undefined'
        : Object.prototype.toString.call(val).slice(8, -1);
  });

  /**
   * private _uniqContentEquals function.
   * That function is checking equality of 2 iterator contents with 2 assumptions
   * - iterators lengths are the same
   * - iterators values are unique
   *
   * false-positive result will be returned for comparision of, e.g.
   * - [1,2,3] and [1,2,3,4]
   * - [1,1,1] and [1,2,3]
   * */

  function _uniqContentEquals(aIterator, bIterator, stackA, stackB) {
    var a = _arrayFromIterator(aIterator);
    var b = _arrayFromIterator(bIterator);

    function eq(_a, _b) {
      return _equals(_a, _b, stackA.slice(), stackB.slice());
    }

    // if *a* array contains any element that is not included in *b*
    return !_includesWith(function(b, aItem) {
      return !_includesWith(eq, aItem, b);
    }, b, a);
  }

  function _equals(a, b, stackA, stackB) {
    if (_objectIs$1(a, b)) {
      return true;
    }

    var typeA = type(a);

    if (typeA !== type(b)) {
      return false;
    }

    if (a == null || b == null) {
      return false;
    }

    if (typeof a['fantasy-land/equals'] === 'function' || typeof b['fantasy-land/equals'] === 'function') {
      return typeof a['fantasy-land/equals'] === 'function' && a['fantasy-land/equals'](b) &&
        typeof b['fantasy-land/equals'] === 'function' && b['fantasy-land/equals'](a);
    }

    if (typeof a.equals === 'function' || typeof b.equals === 'function') {
      return typeof a.equals === 'function' && a.equals(b) &&
        typeof b.equals === 'function' && b.equals(a);
    }

    switch (typeA) {
      case 'Arguments':
      case 'Array':
      case 'Object':
        if (typeof a.constructor === 'function' &&
          _functionName(a.constructor) === 'Promise') {
          return a === b;
        }
        break;
      case 'Boolean':
      case 'Number':
      case 'String':
        if (!(typeof a === typeof b && _objectIs$1(a.valueOf(), b.valueOf()))) {
          return false;
        }
        break;
      case 'Date':
        if (!_objectIs$1(a.valueOf(), b.valueOf())) {
          return false;
        }
        break;
      case 'Error':
        return a.name === b.name && a.message === b.message;
      case 'RegExp':
        if (!(a.source === b.source &&
            a.global === b.global &&
            a.ignoreCase === b.ignoreCase &&
            a.multiline === b.multiline &&
            a.sticky === b.sticky &&
            a.unicode === b.unicode)) {
          return false;
        }
        break;
    }

    var idx = stackA.length - 1;
    while (idx >= 0) {
      if (stackA[idx] === a) {
        return stackB[idx] === b;
      }
      idx -= 1;
    }

    switch (typeA) {
      case 'Map':
        if (a.size !== b.size) {
          return false;
        }

        return _uniqContentEquals(a.entries(), b.entries(), stackA.concat([a]), stackB.concat([b]));
      case 'Set':
        if (a.size !== b.size) {
          return false;
        }

        return _uniqContentEquals(a.values(), b.values(), stackA.concat([a]), stackB.concat([b]));
      case 'Arguments':
      case 'Array':
      case 'Object':
      case 'Boolean':
      case 'Number':
      case 'String':
      case 'Date':
      case 'Error':
      case 'RegExp':
      case 'Int8Array':
      case 'Uint8Array':
      case 'Uint8ClampedArray':
      case 'Int16Array':
      case 'Uint16Array':
      case 'Int32Array':
      case 'Uint32Array':
      case 'Float32Array':
      case 'Float64Array':
      case 'ArrayBuffer':
        break;
      default:
        // Values of other types are only equal if identical.
        return false;
    }

    var keysA = keys(a);
    if (keysA.length !== keys(b).length) {
      return false;
    }

    var extendedStackA = stackA.concat([a]);
    var extendedStackB = stackB.concat([b]);

    idx = keysA.length - 1;
    while (idx >= 0) {
      var key = keysA[idx];
      if (!(_has(key, b) && _equals(b[key], a[key], extendedStackA, extendedStackB))) {
        return false;
      }
      idx -= 1;
    }
    return true;
  }

  /**
   * Returns `true` if its arguments are equivalent, `false` otherwise. Handles
   * cyclical data structures.
   *
   * Dispatches symmetrically to the `equals` methods of both arguments, if
   * present.
   *
   * @func
   * @memberOf R
   * @since v0.15.0
   * @category Relation
   * @sig a -> b -> Boolean
   * @param {*} a
   * @param {*} b
   * @return {Boolean}
   * @example
   *
   *      R.equals(1, 1); //=> true
   *      R.equals(1, '1'); //=> false
   *      R.equals([1, 2, 3], [1, 2, 3]); //=> true
   *
   *      const a = {}; a.v = a;
   *      const b = {}; b.v = b;
   *      R.equals(a, b); //=> true
   */
  var equals = _curry2(function equals(a, b) {
    return _equals(a, b, [], []);
  });

  function _indexOf(list, a, idx) {
    var inf, item;
    // Array.prototype.indexOf doesn't exist below IE9
    if (typeof list.indexOf === 'function') {
      switch (typeof a) {
        case 'number':
          if (a === 0) {
            // manually crawl the list to distinguish between +0 and -0
            inf = 1 / a;
            while (idx < list.length) {
              item = list[idx];
              if (item === 0 && 1 / item === inf) {
                return idx;
              }
              idx += 1;
            }
            return -1;
          } else if (a !== a) {
            // NaN
            while (idx < list.length) {
              item = list[idx];
              if (typeof item === 'number' && item !== item) {
                return idx;
              }
              idx += 1;
            }
            return -1;
          }
          // non-zero numbers can utilise Set
          return list.indexOf(a, idx);

        // all these types can utilise Set
        case 'string':
        case 'boolean':
        case 'function':
        case 'undefined':
          return list.indexOf(a, idx);

        case 'object':
          if (a === null) {
            // null can utilise Set
            return list.indexOf(a, idx);
          }
      }
    }
    // anything else not covered above, defer to R.equals
    while (idx < list.length) {
      if (equals(list[idx], a)) {
        return idx;
      }
      idx += 1;
    }
    return -1;
  }

  function _includes(a, list) {
    return _indexOf(list, a, 0) >= 0;
  }

  function _Set() {
    /* globals Set */
    this._nativeSet = typeof Set === 'function' ? new Set() : null;
    this._items = {};
  }

  // until we figure out why jsdoc chokes on this
  // @param item The item to add to the Set
  // @returns {boolean} true if the item did not exist prior, otherwise false
  //
  _Set.prototype.add = function(item) {
    return !hasOrAdd(item, true, this);
  };

  //
  // @param item The item to check for existence in the Set
  // @returns {boolean} true if the item exists in the Set, otherwise false
  //
  _Set.prototype.has = function(item) {
    return hasOrAdd(item, false, this);
  };

  //
  // Combines the logic for checking whether an item is a member of the set and
  // for adding a new item to the set.
  //
  // @param item       The item to check or add to the Set instance.
  // @param shouldAdd  If true, the item will be added to the set if it doesn't
  //                   already exist.
  // @param set        The set instance to check or add to.
  // @return {boolean} true if the item already existed, otherwise false.
  //
  function hasOrAdd(item, shouldAdd, set) {
    var type = typeof item;
    var prevSize, newSize;
    switch (type) {
      case 'string':
      case 'number':
        // distinguish between +0 and -0
        if (item === 0 && 1 / item === -Infinity) {
          if (set._items['-0']) {
            return true;
          } else {
            if (shouldAdd) {
              set._items['-0'] = true;
            }
            return false;
          }
        }
        // these types can all utilise the native Set
        if (set._nativeSet !== null) {
          if (shouldAdd) {
            prevSize = set._nativeSet.size;
            set._nativeSet.add(item);
            newSize = set._nativeSet.size;
            return newSize === prevSize;
          } else {
            return set._nativeSet.has(item);
          }
        } else {
          if (!(type in set._items)) {
            if (shouldAdd) {
              set._items[type] = {};
              set._items[type][item] = true;
            }
            return false;
          } else if (item in set._items[type]) {
            return true;
          } else {
            if (shouldAdd) {
              set._items[type][item] = true;
            }
            return false;
          }
        }

      case 'boolean':
        // set._items['boolean'] holds a two element array
        // representing [ falseExists, trueExists ]
        if (type in set._items) {
          var bIdx = item ? 1 : 0;
          if (set._items[type][bIdx]) {
            return true;
          } else {
            if (shouldAdd) {
              set._items[type][bIdx] = true;
            }
            return false;
          }
        } else {
          if (shouldAdd) {
            set._items[type] = item ? [false, true] : [true, false];
          }
          return false;
        }

      case 'function':
        // compare functions for reference equality
        if (set._nativeSet !== null) {
          if (shouldAdd) {
            prevSize = set._nativeSet.size;
            set._nativeSet.add(item);
            newSize = set._nativeSet.size;
            return newSize === prevSize;
          } else {
            return set._nativeSet.has(item);
          }
        } else {
          if (!(type in set._items)) {
            if (shouldAdd) {
              set._items[type] = [item];
            }
            return false;
          }
          if (!_includes(item, set._items[type])) {
            if (shouldAdd) {
              set._items[type].push(item);
            }
            return false;
          }
          return true;
        }

      case 'undefined':
        if (set._items[type]) {
          return true;
        } else {
          if (shouldAdd) {
            set._items[type] = true;
          }
          return false;
        }

      case 'object':
        if (item === null) {
          if (!set._items['null']) {
            if (shouldAdd) {
              set._items['null'] = true;
            }
            return false;
          }
          return true;
        }
      /* falls through */
      default:
        // reduce the search size of heterogeneous sets by creating buckets
        // for each type.
        type = Object.prototype.toString.call(item);
        if (!(type in set._items)) {
          if (shouldAdd) {
            set._items[type] = [item];
          }
          return false;
        }
        // scan through all previously applied items
        if (!_includes(item, set._items[type])) {
          if (shouldAdd) {
            set._items[type].push(item);
          }
          return false;
        }
        return true;
    }
  }

  /**
   * Returns a new list containing only one copy of each element in the original
   * list, based upon the value returned by applying the supplied function to
   * each list element. Prefers the first item if the supplied function produces
   * the same value on two items. [`R.equals`](#equals) is used for comparison.
   *
   * @func
   * @memberOf R
   * @since v0.16.0
   * @category List
   * @sig (a -> b) -> [a] -> [a]
   * @param {Function} fn A function used to produce a value to use during comparisons.
   * @param {Array} list The array to consider.
   * @return {Array} The list of unique items.
   * @example
   *
   *      R.uniqBy(Math.abs, [-1, -5, 2, 10, 1, 2]); //=> [-1, -5, 2, 10]
   */
  var uniqBy = _curry2(function uniqBy(fn, list) {
    var set = new _Set();
    var result = [];
    var idx = 0;
    var appliedItem, item;

    while (idx < list.length) {
      item = list[idx];
      appliedItem = fn(item);
      if (set.add(appliedItem)) {
        result.push(item);
      }
      idx += 1;
    }
    return result;
  });

  exports.uniqBy = uniqBy;

  Object.defineProperty(exports, '__esModule', { value: true });

})));