ember-source/dist/packages/@ember/object/lib/computed/reduce_computed_macros.js

A JavaScript framework for creating ambitious web applications

/**
@module @ember/object
*/
import { DEBUG } from '@glimmer/env';
import { assert } from '@ember/debug';
import { autoComputed, isElementDescriptor } from '@ember/-internals/metal';
import { computed, get } from '@ember/object';
import { compare } from '@ember/utils';
import EmberArray, { A as emberA, uniqBy as uniqByArray } from '@ember/array';
function isNativeOrEmberArray(obj) {
  return Array.isArray(obj) || EmberArray.detect(obj);
}
function reduceMacro(dependentKey, callback, initialValue, name) {
  assert(`Dependent key passed to \`${name}\` computed macro shouldn't contain brace expanding pattern.`, !/[[\]{}]/g.test(dependentKey));
  return computed(`${dependentKey}.[]`, function () {
    let arr = get(this, dependentKey);
    if (arr === null || typeof arr !== 'object') {
      return initialValue;
    }
    return arr.reduce(callback, initialValue, this);
  }).readOnly();
}
function arrayMacro(dependentKey, additionalDependentKeys, callback) {
  // This is a bit ugly
  let propertyName;
  if (/@each/.test(dependentKey)) {
    propertyName = dependentKey.replace(/\.@each.*$/, '');
  } else {
    propertyName = dependentKey;
    dependentKey += '.[]';
  }
  return computed(dependentKey, ...additionalDependentKeys, function () {
    let value = get(this, propertyName);
    if (isNativeOrEmberArray(value)) {
      return emberA(callback.call(this, value));
    } else {
      return emberA();
    }
  }).readOnly();
}
function multiArrayMacro(_dependentKeys, callback, name) {
  assert(`Dependent keys passed to \`${name}\` computed macro shouldn't contain brace expanding pattern.`, _dependentKeys.every(dependentKey => !/[[\]{}]/g.test(dependentKey)));
  let dependentKeys = _dependentKeys.map(key => `${key}.[]`);
  return computed(...dependentKeys, function () {
    return emberA(callback.call(this, _dependentKeys));
  }).readOnly();
}
/**
  A computed property that returns the sum of the values in the dependent array.

  Example:

  ```javascript
  import { sum } from '@ember/object/computed';

  class Invoice {
    lineItems = [1.00, 2.50, 9.99];

    @sum('lineItems') total;
  }

  let invoice = new Invoice();

  invoice.total; // 13.49
  ```

  @method sum
  @for @ember/object/computed
  @static
  @param {String} dependentKey
  @return {ComputedProperty} computes the sum of all values in the
  dependentKey's array
  @since 1.4.0
  @public
*/
export function sum(dependentKey) {
  assert('You attempted to use @sum as a decorator directly, but it requires a `dependentKey` parameter', !isElementDescriptor(Array.prototype.slice.call(arguments)));
  return reduceMacro(dependentKey, (sum, item) => sum + item, 0, 'sum');
}
/**
  A computed property that calculates the maximum value in the dependent array.
  This will return `-Infinity` when the dependent array is empty.

  Example:

  ```javascript
  import { set } from '@ember/object';
  import { mapBy, max } from '@ember/object/computed';

  class Person {
    children = [];

    @mapBy('children', 'age') childAges;
    @max('childAges') maxChildAge;
  }

  let lordByron = new Person();

  lordByron.maxChildAge; // -Infinity

  set(lordByron, 'children', [
    {
      name: 'Augusta Ada Byron',
      age: 7
    }
  ]);
  lordByron.maxChildAge; // 7

  set(lordByron, 'children', [
    ...lordByron.children,
    {
      name: 'Allegra Byron',
      age: 5
    }, {
      name: 'Elizabeth Medora Leigh',
      age: 8
    }
  ]);
  lordByron.maxChildAge; // 8
  ```

  If the types of the arguments are not numbers, they will be converted to
  numbers and the type of the return value will always be `Number`. For example,
  the max of a list of Date objects will be the highest timestamp as a `Number`.
  This behavior is consistent with `Math.max`.

  @method max
  @for @ember/object/computed
  @static
  @param {String} dependentKey
  @return {ComputedProperty} computes the largest value in the dependentKey's
  array
  @public
*/
export function max(dependentKey) {
  assert('You attempted to use @max as a decorator directly, but it requires a `dependentKey` parameter', !isElementDescriptor(Array.prototype.slice.call(arguments)));
  return reduceMacro(dependentKey, (max, item) => Math.max(max, item), -Infinity, 'max');
}
/**
  A computed property that calculates the minimum value in the dependent array.
  This will return `Infinity` when the dependent array is empty.

  Example:

  ```javascript
  import { set } from '@ember/object';
  import { mapBy, min } from '@ember/object/computed';

  class Person {
    children = [];

    @mapBy('children', 'age') childAges;
    @min('childAges') minChildAge;
  }

  let lordByron = Person.create({ children: [] });

  lordByron.minChildAge; // Infinity

  set(lordByron, 'children', [
    {
      name: 'Augusta Ada Byron',
      age: 7
    }
  ]);
  lordByron.minChildAge; // 7

  set(lordByron, 'children', [
    ...lordByron.children,
    {
      name: 'Allegra Byron',
      age: 5
    }, {
      name: 'Elizabeth Medora Leigh',
      age: 8
    }
  ]);
  lordByron.minChildAge; // 5
  ```

  If the types of the arguments are not numbers, they will be converted to
  numbers and the type of the return value will always be `Number`. For example,
  the min of a list of Date objects will be the lowest timestamp as a `Number`.
  This behavior is consistent with `Math.min`.

  @method min
  @for @ember/object/computed
  @static
  @param {String} dependentKey
  @return {ComputedProperty} computes the smallest value in the dependentKey's array
  @public
*/
export function min(dependentKey) {
  assert('You attempted to use @min as a decorator directly, but it requires a `dependentKey` parameter', !isElementDescriptor(Array.prototype.slice.call(arguments)));
  return reduceMacro(dependentKey, (min, item) => Math.min(min, item), Infinity, 'min');
}
export function map(dependentKey, additionalDependentKeysOrCallback, callback) {
  assert('You attempted to use @map as a decorator directly, but it requires atleast `dependentKey` and `callback` parameters', !isElementDescriptor(Array.prototype.slice.call(arguments)));
  assert('The final parameter provided to map must be a callback function', typeof callback === 'function' || callback === undefined && typeof additionalDependentKeysOrCallback === 'function');
  assert('The second parameter provided to map must either be the callback or an array of additional dependent keys', Array.isArray(additionalDependentKeysOrCallback) || typeof additionalDependentKeysOrCallback === 'function');
  let additionalDependentKeys;
  if (typeof additionalDependentKeysOrCallback === 'function') {
    callback = additionalDependentKeysOrCallback;
    additionalDependentKeys = [];
  } else {
    additionalDependentKeys = additionalDependentKeysOrCallback;
  }
  const cCallback = callback;
  assert('[BUG] Missing callback', cCallback);
  return arrayMacro(dependentKey, additionalDependentKeys, function (value) {
    // This is so dumb...
    return Array.isArray(value) ? value.map(cCallback, this) : value.map(cCallback, this);
  });
}
/**
  Returns an array mapped to the specified key.

  Example:

  ```javascript
  import { set } from '@ember/object';
  import { mapBy } from '@ember/object/computed';

  class Person {
    children = [];

    @mapBy('children', 'age') childAges;
  }

  let lordByron = new Person();

  lordByron.childAges; // []

  set(lordByron, 'children', [
    {
      name: 'Augusta Ada Byron',
      age: 7
    }
  ]);
  lordByron.childAges; // [7]

  set(lordByron, 'children', [
    ...lordByron.children,
    {
      name: 'Allegra Byron',
      age: 5
    }, {
      name: 'Elizabeth Medora Leigh',
      age: 8
    }
  ]);
  lordByron.childAges; // [7, 5, 8]
  ```

  @method mapBy
  @for @ember/object/computed
  @static
  @param {String} dependentKey
  @param {String} propertyKey
  @return {ComputedProperty} an array mapped to the specified key
  @public
*/
export function mapBy(dependentKey, propertyKey) {
  assert('You attempted to use @mapBy as a decorator directly, but it requires `dependentKey` and `propertyKey` parameters', !isElementDescriptor(Array.prototype.slice.call(arguments)));
  assert('`mapBy` computed macro expects a property string for its second argument, ' + 'perhaps you meant to use "map"', typeof propertyKey === 'string');
  assert(`Dependent key passed to \`mapBy\` computed macro shouldn't contain brace expanding pattern.`, !/[[\]{}]/g.test(dependentKey));
  return map(`${dependentKey}.@each.${propertyKey}`, item => get(item, propertyKey));
}
export function filter(dependentKey, additionalDependentKeysOrCallback, callback) {
  assert('You attempted to use @filter as a decorator directly, but it requires atleast `dependentKey` and `callback` parameters', !isElementDescriptor(Array.prototype.slice.call(arguments)));
  assert('The final parameter provided to filter must be a callback function', typeof callback === 'function' || callback === undefined && typeof additionalDependentKeysOrCallback === 'function');
  assert('The second parameter provided to filter must either be the callback or an array of additional dependent keys', Array.isArray(additionalDependentKeysOrCallback) || typeof additionalDependentKeysOrCallback === 'function');
  let additionalDependentKeys;
  if (typeof additionalDependentKeysOrCallback === 'function') {
    callback = additionalDependentKeysOrCallback;
    additionalDependentKeys = [];
  } else {
    additionalDependentKeys = additionalDependentKeysOrCallback;
  }
  const cCallback = callback;
  return arrayMacro(dependentKey, additionalDependentKeys, function (value) {
    // This is a really silly way to keep TS happy
    return Array.isArray(value) ? value.filter(cCallback, this) : value.filter(cCallback, this);
  });
}
/**
  Filters the array by the property and value.

  Example:

  ```javascript
  import { set } from '@ember/object';
  import { filterBy } from '@ember/object/computed';

  class Hamster {
    constructor(chores) {
      set(this, 'chores', chores);
    }

    @filterBy('chores', 'done', false) remainingChores;
  }

  let hamster = new Hamster([
    { name: 'cook', done: true },
    { name: 'clean', done: true },
    { name: 'write more unit tests', done: false }
  ]);

  hamster.remainingChores; // [{ name: 'write more unit tests', done: false }]
  ```

  @method filterBy
  @for @ember/object/computed
  @static
  @param {String} dependentKey
  @param {String} propertyKey
  @param {*} value
  @return {ComputedProperty} the filtered array
  @public
*/
export function filterBy(dependentKey, propertyKey, value) {
  assert('You attempted to use @filterBy as a decorator directly, but it requires atleast `dependentKey` and `propertyKey` parameters', !isElementDescriptor(Array.prototype.slice.call(arguments)));
  assert(`Dependent key passed to \`filterBy\` computed macro shouldn't contain brace expanding pattern.`, !/[[\]{}]/g.test(dependentKey));
  let callback;
  if (arguments.length === 2) {
    callback = item => get(item, propertyKey);
  } else {
    callback = item => get(item, propertyKey) === value;
  }
  return filter(`${dependentKey}.@each.${propertyKey}`, callback);
}
/**
  A computed property which returns a new array with all the unique elements
  from one or more dependent arrays.

  Example:

  ```javascript
  import { set } from '@ember/object';
  import { uniq } from '@ember/object/computed';

  class Hamster {
    constructor(fruits) {
      set(this, 'fruits', fruits);
    }

    @uniq('fruits') uniqueFruits;
  }

  let hamster = new Hamster([
    'banana',
    'grape',
    'kale',
    'banana'
  ]);

  hamster.uniqueFruits; // ['banana', 'grape', 'kale']
  ```

  @method uniq
  @for @ember/object/computed
  @static
  @param {String} propertyKey*
  @return {ComputedProperty} computes a new array with all the
  unique elements from the dependent array
  @public
*/
export function uniq(dependentKey, ...additionalDependentKeys) {
  assert('You attempted to use @uniq/@union as a decorator directly, but it requires atleast one dependent key parameter', !isElementDescriptor(Array.prototype.slice.call(arguments)));
  let args = [dependentKey, ...additionalDependentKeys];
  return multiArrayMacro(args, function (dependentKeys) {
    let uniq = emberA();
    let seen = new Set();
    dependentKeys.forEach(dependentKey => {
      let value = get(this, dependentKey);
      if (isNativeOrEmberArray(value)) {
        value.forEach(item => {
          if (!seen.has(item)) {
            seen.add(item);
            uniq.push(item);
          }
        });
      }
    });
    return uniq;
  }, 'uniq');
}
/**
  A computed property which returns a new array with all the unique elements
  from an array, with uniqueness determined by specific key.

  Example:

  ```javascript
  import { set } from '@ember/object';
  import { uniqBy } from '@ember/object/computed';

  class Hamster {
    constructor(fruits) {
      set(this, 'fruits', fruits);
    }

    @uniqBy('fruits', 'id') uniqueFruits;
  }

  let hamster = new Hamster([
    { id: 1, 'banana' },
    { id: 2, 'grape' },
    { id: 3, 'peach' },
    { id: 1, 'banana' }
  ]);

  hamster.uniqueFruits; // [ { id: 1, 'banana' }, { id: 2, 'grape' }, { id: 3, 'peach' }]
  ```

  @method uniqBy
  @for @ember/object/computed
  @static
  @param {String} dependentKey
  @param {String} propertyKey
  @return {ComputedProperty} computes a new array with all the
  unique elements from the dependent array
  @public
*/
export function uniqBy(dependentKey, propertyKey) {
  assert('You attempted to use @uniqBy as a decorator directly, but it requires `dependentKey` and `propertyKey` parameters', !isElementDescriptor(Array.prototype.slice.call(arguments)));
  assert(`Dependent key passed to \`uniqBy\` computed macro shouldn't contain brace expanding pattern.`, !/[[\]{}]/g.test(dependentKey));
  return computed(`${dependentKey}.[]`, function () {
    let list = get(this, dependentKey);
    return isNativeOrEmberArray(list) ? uniqByArray(list, propertyKey) : emberA();
  }).readOnly();
}
/**
  A computed property which returns a new array with all the unique elements
  from one or more dependent arrays.

  Example:

  ```javascript
  import { set } from '@ember/object';
  import { union } from '@ember/object/computed';

  class Hamster {
    constructor(fruits, vegetables) {
      set(this, 'fruits', fruits);
      set(this, 'vegetables', vegetables);
    }

    @union('fruits', 'vegetables') uniqueFruits;
  });

  let hamster = new, Hamster(
    [
      'banana',
      'grape',
      'kale',
      'banana',
      'tomato'
    ],
    [
      'tomato',
      'carrot',
      'lettuce'
    ]
  );

  hamster.uniqueFruits; // ['banana', 'grape', 'kale', 'tomato', 'carrot', 'lettuce']
  ```

  @method union
  @for @ember/object/computed
  @static
  @param {String} propertyKey*
  @return {ComputedProperty} computes a new array with all the unique elements
  from one or more dependent arrays.
  @public
*/
export let union = uniq;
/**
  A computed property which returns a new array with all the elements
  two or more dependent arrays have in common.

  Example:

  ```javascript
  import { set } from '@ember/object';
  import { intersect } from '@ember/object/computed';

  class FriendGroups {
    constructor(adaFriends, charlesFriends) {
      set(this, 'adaFriends', adaFriends);
      set(this, 'charlesFriends', charlesFriends);
    }

    @intersect('adaFriends', 'charlesFriends') friendsInCommon;
  }

  let groups = new FriendGroups(
    ['Charles Babbage', 'John Hobhouse', 'William King', 'Mary Somerville'],
    ['William King', 'Mary Somerville', 'Ada Lovelace', 'George Peacock']
  );

  groups.friendsInCommon; // ['William King', 'Mary Somerville']
  ```

  @method intersect
  @for @ember/object/computed
  @static
  @param {String} propertyKey*
  @return {ComputedProperty} computes a new array with all the duplicated
  elements from the dependent arrays
  @public
*/
export function intersect(dependentKey, ...additionalDependentKeys) {
  assert('You attempted to use @intersect as a decorator directly, but it requires atleast one dependent key parameter', !isElementDescriptor(Array.prototype.slice.call(arguments)));
  let args = [dependentKey, ...additionalDependentKeys];
  return multiArrayMacro(args, function (dependentKeys) {
    let arrays = dependentKeys.map(dependentKey => {
      let array = get(this, dependentKey);
      return Array.isArray(array) ? array : [];
    });
    let firstArray = arrays.pop();
    assert('Attempted to apply multiArrayMacro for intersect without any dependentKeys', firstArray);
    let results = firstArray.filter(candidate => {
      for (let array of arrays) {
        let found = false;
        for (let item of array) {
          if (item === candidate) {
            found = true;
            break;
          }
        }
        if (found === false) {
          return false;
        }
      }
      return true;
    });
    return emberA(results);
  }, 'intersect');
}
/**
  A computed property which returns a new array with all the properties from the
  first dependent array that are not in the second dependent array.

  Example:

  ```javascript
  import { set } from '@ember/object';
  import { setDiff } from '@ember/object/computed';

  class Hamster {
    constructor(likes, fruits) {
      set(this, 'likes', likes);
      set(this, 'fruits', fruits);
    }

    @setDiff('likes', 'fruits') wants;
  }

  let hamster = new Hamster(
    [
      'banana',
      'grape',
      'kale'
    ],
    [
      'grape',
      'kale',
    ]
  );

  hamster.wants; // ['banana']
  ```

  @method setDiff
  @for @ember/object/computed
  @static
  @param {String} setAProperty
  @param {String} setBProperty
  @return {ComputedProperty} computes a new array with all the items from the
  first dependent array that are not in the second dependent array
  @public
*/
export function setDiff(setAProperty, setBProperty) {
  assert('You attempted to use @setDiff as a decorator directly, but it requires atleast one dependent key parameter', !isElementDescriptor(Array.prototype.slice.call(arguments)));
  assert('`setDiff` computed macro requires exactly two dependent arrays.', arguments.length === 2);
  assert(`Dependent keys passed to \`setDiff\` computed macro shouldn't contain brace expanding pattern.`, !/[[\]{}]/g.test(setAProperty) && !/[[\]{}]/g.test(setBProperty));
  return computed(`${setAProperty}.[]`, `${setBProperty}.[]`, function () {
    let setA = get(this, setAProperty);
    let setB = get(this, setBProperty);
    if (!isNativeOrEmberArray(setA)) {
      return emberA();
    }
    if (!isNativeOrEmberArray(setB)) {
      return setA;
    }
    return setA.filter(x => setB.indexOf(x) === -1);
  }).readOnly();
}
/**
  A computed property that returns the array of values for the provided
  dependent properties.

  Example:

  ```javascript
  import { set } from '@ember/object';
  import { collect } from '@ember/object/computed';

  class Hamster {
    @collect('hat', 'shirt') clothes;
  }

  let hamster = new Hamster();

  hamster.clothes; // [null, null]

  set(hamster, 'hat', 'Camp Hat');
  set(hamster, 'shirt', 'Camp Shirt');
  hamster.clothes; // ['Camp Hat', 'Camp Shirt']
  ```

  @method collect
  @for @ember/object/computed
  @static
  @param {String} dependentKey*
  @return {ComputedProperty} computed property which maps values of all passed
  in properties to an array.
  @public
*/
export function collect(dependentKey, ...additionalDependentKeys) {
  assert('You attempted to use @collect as a decorator directly, but it requires atleast one dependent key parameter', !isElementDescriptor(Array.prototype.slice.call(arguments)));
  let dependentKeys = [dependentKey, ...additionalDependentKeys];
  return multiArrayMacro(dependentKeys, function () {
    let res = dependentKeys.map(key => {
      let val = get(this, key);
      return val === undefined ? null : val;
    });
    return emberA(res);
  }, 'collect');
}
export function sort(itemsKey, additionalDependentKeysOrDefinition, sortDefinition) {
  assert('You attempted to use @sort as a decorator directly, but it requires atleast an `itemsKey` parameter', !isElementDescriptor(Array.prototype.slice.call(arguments)));
  if (DEBUG) {
    let argumentsValid = false;
    if (arguments.length === 2) {
      argumentsValid = typeof itemsKey === 'string' && (typeof additionalDependentKeysOrDefinition === 'string' || typeof additionalDependentKeysOrDefinition === 'function');
    }
    if (arguments.length === 3) {
      argumentsValid = typeof itemsKey === 'string' && Array.isArray(additionalDependentKeysOrDefinition) && typeof sortDefinition === 'function';
    }
    assert('The `sort` computed macro can either be used with an array of sort properties or with a sort function. If used with an array of sort properties, it must receive exactly two arguments: the key of the array to sort, and the key of the array of sort properties. If used with a sort function, it may receive up to three arguments: the key of the array to sort, an optional additional array of dependent keys for the computed property, and the sort function.', argumentsValid);
  }
  let additionalDependentKeys;
  let sortDefinitionOrString;
  if (Array.isArray(additionalDependentKeysOrDefinition)) {
    additionalDependentKeys = additionalDependentKeysOrDefinition;
    sortDefinitionOrString = sortDefinition;
  } else {
    additionalDependentKeys = [];
    sortDefinitionOrString = additionalDependentKeysOrDefinition;
  }
  if (typeof sortDefinitionOrString === 'function') {
    return customSort(itemsKey, additionalDependentKeys, sortDefinitionOrString);
  } else {
    return propertySort(itemsKey, sortDefinitionOrString);
  }
}
function customSort(itemsKey, additionalDependentKeys, comparator) {
  return arrayMacro(itemsKey, additionalDependentKeys, function (value) {
    return value.slice().sort((x, y) => comparator.call(this, x, y));
  });
}
// This one needs to dynamically set up and tear down observers on the itemsKey
// depending on the sortProperties
function propertySort(itemsKey, sortPropertiesKey) {
  let cp = autoComputed(function (key) {
    let sortProperties = get(this, sortPropertiesKey);
    assert(`The sort definition for '${key}' on ${this} must be a function or an array of strings`, function (arr) {
      return isNativeOrEmberArray(arr) && arr.every(s => typeof s === 'string');
    }(sortProperties));
    let itemsKeyIsAtThis = itemsKey === '@this';
    let normalizedSortProperties = normalizeSortProperties(sortProperties);
    let items = itemsKeyIsAtThis ? this : get(this, itemsKey);
    if (!isNativeOrEmberArray(items)) {
      return emberA();
    }
    if (normalizedSortProperties.length === 0) {
      return emberA(items.slice());
    } else {
      return sortByNormalizedSortProperties(items, normalizedSortProperties);
    }
  }).readOnly();
  return cp;
}
function normalizeSortProperties(sortProperties) {
  let callback = p => {
    let [prop, direction] = p.split(':');
    direction = direction || 'asc';
    // SAFETY: There will always be at least one value returned by split
    return [prop, direction];
  };
  // This nonsense is necessary since technically the two map implementations diverge.
  return Array.isArray(sortProperties) ? sortProperties.map(callback) : sortProperties.map(callback);
}
function sortByNormalizedSortProperties(items, normalizedSortProperties) {
  return emberA(items.slice().sort((itemA, itemB) => {
    for (let [prop, direction] of normalizedSortProperties) {
      let result = compare(get(itemA, prop), get(itemB, prop));
      if (result !== 0) {
        return direction === 'desc' ? -1 * result : result;
      }
    }
    return 0;
  }));
}