src/core/decorators/track.js
function track(trackingFn, options={ sendReturnValue: true }) {
  let decorator = function(target, name, descriptor) {
    const hasDescriptor = typeof descriptor.value !== "undefined";
    const fn = hasDescriptor ? descriptor.value : target;

    function trackDecorator() {
      let fnReturnValue = fn.apply(this, arguments),
          value = null;
      
      if (options.sendReturnValue) {
        value = fnReturnValue;
      }

      trackEvent(typeof trackingFn === "string" ? 
        Object.assign({ name: trackingFn, data: value }, options) : 
        trackingFn.apply(this, [value]));

      return fnReturnValue;
    };

    if (hasDescriptor) {
      descriptor.value = trackDecorator;
    }
    else {
      target = trackDecorator;
    }
  };

  decorator.sendReturnValue = function(value = true) {
    options.sendReturnValue = !!value;
    return this;
  };

  return decorator;
}
function track(trackingFn, options={ sendReturnValue: true }) {
  let decorator = function(target, name, descriptor) {
    const hasDescriptor = typeof descriptor.value !== "undefined";
    const fn = hasDescriptor ? descriptor.value : target;

    function trackDecorator() {
      let fnReturnValue = fn.apply(this, arguments),
          value = null;
      
      if (options.sendReturnValue) {
        value = fnReturnValue;
      }

      trackEvent(typeof trackingFn === "string" ? 
        Object.assign({ name: trackingFn, data: value }, options) : 
        trackingFn.apply(this, [value]));

      return fnReturnValue;
    };

    if (hasDescriptor) {
      descriptor.value = trackDecorator;
    }
    else {
      target = trackDecorator;
    }
  };

  decorator.sendReturnValue = function(value = true) {
    options.sendReturnValue = !!value;
    return this;
  };

  return decorator;
}
function track ( trackingFn , options = { sendReturnValue : true } ) { let decorator = function ( target , name , descriptor ) { const hasDescriptor = typeof descriptor . value !== "undefined" ; const fn = hasDescriptor ? descriptor . value : target ; function trackDecorator ( ) { let fnReturnValue = fn . apply ( this , arguments ) , value = null ; if ( options . sendReturnValue ) { value = fnReturnValue ; } trackEvent ( typeof trackingFn === "string" ? Object . assign ( { name : trackingFn , data : value } , options ) : trackingFn . apply ( this , [ value ] ) ) ; return fnReturnValue ; } ; if ( hasDescriptor ) { descriptor . value = trackDecorator ; } else { target = trackDecorator ; } } ; decorator . sendReturnValue = function ( value = true ) { options . sendReturnValue = ! ! value ; return this ; } ; return decorator ; }
Use when you need to track a method call w/ the `trackEvent` utility.
The value returned will be passed as `data` to `trackEvent`.
If a function is used for the `trackingFn`, it must return an object w/ a `name`, and optional `data`
@param  {Function|String} trackingFn Either a function to build up the event data or a string event name.
@param  {Object} [options] An opject of options
@param  {Boolean} [options.sendReturnValue] Whether or not to send the return value as data
@return {Function} The decorator function
@example <caption>String Tracking</caption>

class Foo {
@track("Button Clicked")
buttonClicked() {
// ...
return { some: "data" };
}
}
@example <caption>Function</caption>

import FooTracker from "./foo.tracker";

class Foo {
@track(FooTracker.clicked)
buttonClicked() {
// ...
return { some: "data" };
}
}

// foo.tracker.js

export default function clicked(data) {
// data = { some: "data" }
data.otherData = "other data";

return {
name: "Button Clicked",
data
};
}
@example <caption>String Tracking w/ sendReturnValue false</caption>

class Foo {
@track("Button Clicked").sendReturnValue(false)
buttonClicked() {
// ...
return { some: "data" };
}
}
Use when you need to track a method call w / the trackEvent utility . The value returned will be passed as data to trackEvent . If a function is used for the trackingFn it must return an object w / a name and optional data @param { Function|String } trackingFn Either a function to build up the event data or a string event name . @param { Object } [ options ] An opject of options @param { Boolean } [ options . sendReturnValue ] Whether or not to send the return value as data @return { Function } The decorator function @example <caption > String Tracking< / caption >