dist/scripts/vendor.min.js
function sanitizeAndConfigure(scope, options) {
        var selectEl = element.find('md-select-menu');

        if (!options.target) {
          throw new Error($mdUtil.supplant(ERROR_TARGET_EXPECTED, [options.target]));
        }

        angular.extend(options, {
          isRemoved: false,
          target: angular.element(options.target), //make sure it's not a naked dom node
          parent: angular.element(options.parent),
          selectEl: selectEl,
          contentEl: element.find('md-content'),
          optionNodes: selectEl[0].getElementsByTagName('md-option')
        });
      }
function sanitizeAndConfigure(scope, options) {
        var selectEl = element.find('md-select-menu');

        if (!options.target) {
          throw new Error($mdUtil.supplant(ERROR_TARGET_EXPECTED, [options.target]));
        }

        angular.extend(options, {
          isRemoved: false,
          target: angular.element(options.target), //make sure it's not a naked dom node
          parent: angular.element(options.parent),
          selectEl: selectEl,
          contentEl: element.find('md-content'),
          optionNodes: selectEl[0].getElementsByTagName('md-option')
        });
      }
Check for valid opts and set some sane defaults