RepeatParserService.js

/**
 * Parses "repeat" attribute.
 *
 * Taken from AngularJS ngRepeat source code
 * See https://github.com/angular/angular.js/blob/v1.2.15/src/ng/directive/ngRepeat.js#L211
 *
 * Original discussion about parsing "repeat" attribute instead of fully relying on ng-repeat:
 * https://github.com/angular-ui/ui-select/commit/5dd63ad#commitcomment-5504697
 */

uis.service('RepeatParser', ['uiSelectMinErr','$parse', function(uiSelectMinErr, $parse) {
  var self = this;

  /**
   * Example:
   * expression = "address in addresses | filter: {street: $select.search} track by $index"
   * itemName = "address",
   * source = "addresses | filter: {street: $select.search}",
   * trackByExp = "$index",
   */
  self.parse = function(expression) {

    var match = expression.match(/^\s*(?:([\s\S]+?)\s+as\s+)?([\S]+?)\s+in\s+([\s\S]+?)(?:\s+track\s+by\s+([\s\S]+?))?\s*$/);

    if (!match) {
      throw uiSelectMinErr('iexp', "Expected expression in form of '_item_ in _collection_[ track by _id_]' but got '{0}'.",
              expression);
    }

    return {
      itemName: match[2], // (lhs) Left-hand side,
      source: $parse(match[3]),
      trackByExp: match[4],
      modelMapper: $parse(match[1] || match[2])
    };

  };

  self.getGroupNgRepeatExpression = function() {
    return '$group in $select.groups';
  };

  self.getNgRepeatExpression = function(itemName, source, trackByExp, grouped) {
    var expression = itemName + ' in ' + (grouped ? '$group.items' : source);
    if (trackByExp) {
      expression += ' track by ' + trackByExp;
    }
    return expression;
  };
}]);