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APX's avatar
APX
Occasional Contributor
10 years ago

How can I clone objects in TestComplete javascript?

Hi,   a simple Question: how can I clone objects, in javascript without reference,  in TestComplete(is it possible)? I don't found a methode on MSDN and the standard methode "clone()" is not suppor...
  • APX's avatar
    APX
    10 years ago

    So here is my solution for this Problem. We do not have the the option for using 'prototype' or 'constructor'. I have my doubts in terms of this kind of solution but it's better then nothing:

     

     

    function clone( other, obj)
{
    if ( (other === null) || (typeof other !== "object") )
    {
     obj=other;
     return true;
    }    
    obj = obj || {};
    for ( Key in other )
    {
      if(other.hasOwnProperty(Key))
      {                        
        if(typeof other[Key] == 'function') 
        {
           obj[Key]={};  
           eval("obj."+Key.toString()+"="+other[Key].toString());           
        }
        else if(typeof other[Key] == 'object') 
        {
          obj[Key]={};//
          clone(other[Key], obj[Key]);          
        }
        else
        {         
          obj[Key]=other[Key];
        }
      }
    }
    if(obj != null)return true;
    return false;
}

     

    Usage:

    var person={
    fName: "Max",
    lName: "Mustermann",
    hight: 181,    
    motto:{
      autor:"mySelf", 
      text:"my motto",
      printMotto: function(){
        return (this.autor+" : "+this.text);
      }
    },
    printData:function(){
      return this.fName+" ->"+this.lName+" -> "+this.hight+"->"+motto.printMotto(); 
    }
  };

var copy={};
if(clone(person, copy))
   Log.Message(person.printData()+" :: "+copy.printData());
person=null; // or you can use undefined to clear var
Log.Message(copy.printData());
Log.Message(person.printData());// here we will get an error

    I can't compare the memory address of this both variables, so it's not really 100% a deep copy 

    If you have a better way to solve that problem, post it here.

    Thanks.

APX's avatar
APX
Occasional Contributor

So here is my solution for this Problem. We do not have the the option for using 'prototype' or 'constructor'. I have my doubts in terms of this kind of solution but it's better then nothing:

 

 

function clone( other, obj)
{
    if ( (other === null) || (typeof other !== "object") )
    {
     obj=other;
     return true;
    }    
    obj = obj || {};
    for ( Key in other )
    {
      if(other.hasOwnProperty(Key))
      {                        
        if(typeof other[Key] == 'function') 
        {
           obj[Key]={};  
           eval("obj."+Key.toString()+"="+other[Key].toString());           
        }
        else if(typeof other[Key] == 'object') 
        {
          obj[Key]={};//
          clone(other[Key], obj[Key]);          
        }
        else
        {         
          obj[Key]=other[Key];
        }
      }
    }
    if(obj != null)return true;
    return false;
}

 

Usage:

var person={
    fName: "Max",
    lName: "Mustermann",
    hight: 181,    
    motto:{
      autor:"mySelf", 
      text:"my motto",
      printMotto: function(){
        return (this.autor+" : "+this.text);
      }
    },
    printData:function(){
      return this.fName+" ->"+this.lName+" -> "+this.hight+"->"+motto.printMotto(); 
    }
  };

var copy={};
if(clone(person, copy))
   Log.Message(person.printData()+" :: "+copy.printData());
person=null; // or you can use undefined to clear var
Log.Message(copy.printData());
Log.Message(person.printData());// here we will get an error

I can't compare the memory address of this both variables, so it's not really 100% a deep copy 

If you have a better way to solve that problem, post it here.

Thanks.

k_de_boer03's avatar
k_de_boer03
Contributor
10 years ago

TestComplete actually uses Jscript, so some Javascript functions and libraries are not supported here.

 

I couldn't find a one-liner solution for your problem either. Any solution I found looked similar to your implementation, though I do have a comment.

Why do you want to return a boolean? I would return the copied object, or null if something is wrong. This way you dont need the second argument to the function. Right now with your code:

 

if((other === null) || (typeof other !== "object")) {
  return true;
}

It doesn't make sense to me, why would you return true when nothing happened?

 

Also, you already do:

 

obj = obj || {};

with your second argument, and in your example code you do:

 

var copy={};
if(clone(person, copy))
...

There is no need to do var copy = {}. If you would do var copy = {//some non-empty object}, then it wouldn't be a clone anymore, so thats another reason to remove the argument.

 

I would make it something like:

 

function clone(obj)
{
    if((obj === null) || (typeof obj !== "object")){
        return null; // or throw an error
    }    
    var cloneObj = {};
    for(var prop in obj){
      if(obj.hasOwnProperty(prop)){                        
        if(typeof obj[prop] == 'object'){
          cloneObj[prop] = clone(obj[prop]);          
        } else {         
          cloneObj[prop] = obj[prop];
        }
      }
    }
    return cloneObj;
}

Note, I haven't tested this code :) 

 

  • APX's avatar
    APX
    Occasional Contributor
    10 years ago

    It is only an example...

     

    1.) the the second argument in functions head was important for me, because: 

    function clone( other, obj)

    if this function return an object to an object is that like : var myObj = otherObj; so its save the reference from otherObj to myObj and the function that I have posted  works with the real variable.( my opinion)

     

    2.) The idea is:

    this function is for objects, functions and for standard types like: string or int, float, double, therefore the function don't return false on this: 

    if((other === null) || (typeof other !== "object")) {
      obj = other;
  return true;
}

     

    thanks for answer, the code has become shorter.