In the event object for an onEdit trigger how is it that range get's defined as a real range object and a property identifier at the same time?

I believe your goal as follows.

• You want to create an event object like the event object returned with OnEdit event trigger using Google Apps Script.

For this, how about this answer?

I think that the event object from the OnEdit event trigger is returned from the internal server at Google side. So I'm not sure about the actual script for this. So in this answer, I would like to propose the method for creating the pseudo event object as you say.

In this answer, I used the JavaScript classes which can be used with V8. But I'm not sure whether this is the direction you expect.

Sample script:

In order to use this script, please copy and paste the following script to the script editor, and save it. Then, please edit the cell. By this, onEdit is run by the OnEdit event trigger.

const createEventObject = obj => {
  // Class for creating the range object.
  class createRangeObject {
    constructor(obj) {
      this.columnEnd = obj.columnEnd;
      this.columnStart = obj.columnStart;
      this.rowEnd = obj.rowEnd;
      this.rowStart = obj.rowStart;
    }

    getA1Notation() {
      return SpreadsheetApp
        .getActiveSheet()
        .getRange(this.rowStart, this.columnStart, this.rowEnd - this.rowStart + 1, this.columnEnd - this.columnStart + 1)
        .getA1Notation();
    }

    getSheet() {
      return SpreadsheetApp
        .getActiveSheet();
    }
  }

  // Main script of createEventObject.
  class main {
    constructor(obj) {
      this.obj = obj;
    }

    get range() {
      return new createRangeObject(this.obj);
    }
  }
  return new main(obj);
}

// This function is run by editing cells.
function onEdit(e) {
  // This is your object.
  var myObj={range:{columnStart:e.range.columnStart,rowStart:e.range.rowStart,columnEnd:e.range.columnEnd,rowEnd:e.range.rowEnd}};

  // Create the pseudo event object.
  const obj = createEventObject(myObj.range);

  console.log(obj.range)
  console.log(obj.range.getA1Notation())
  console.log(obj.range.getSheet().getSheetName())
}

Result:

In above sample script, for example, when the cells "B3:C5" are edited, the following result are retrieved.

• obj.range is { columnEnd: 3, columnStart: 2, rowEnd: 5, rowStart: 3 }.
• obj.range.getA1Notation() is B3:C5.
• obj.range.getSheet().getSheetName() is Sheet1 which is the active sheet.

Note:

• This answer, which uses the JavaScript classes, is one methodology. So I think that there might be more simpler methods.
• This is a simple script for explaining of this workaround. So when you want to use this for your actual situation, please modify this.
• Please use this script with V8.

Reference:

• Classes

The first function here is executed with the RunOnXdit button in the sidebar and it called the onXdit() function passing a psuedo onEdit trigger event object along with a mode property so that I can distinguish between running in test mode and running in live mode.

function onXditTest(row) {
  var row=row||2;
  console.log('row: ' + row);
  const ss=SpreadsheetApp.getActive();
  const sh=ss.getSheetByName('OnEditTest');
  const v=sh.getRange(row,1,1,sh.getLastColumn()).getValues()[0];
  const xsh=ss.getSheetByName(v[5]);
  const xrg=xsh.getRange(v[0],v[2],v[1]-v[0]+1,v[3]-v[2]+1);
  var evobj={value:v[4]?"TRUE":"FALSE",source:ss,mode:true};
  evobj.range=xrg;//assign Class Range Object
  evobj.range.rowStart=v[0];
  evobj.range.rowEnd=v[1];
  evobj.range.columnEnd=v[3];
  evobj.range.columnStart=v[2]
  onXdit(evobj);
}

The second function can be run from the above function or it can be run from the onEdit trigger with the same code. The above function is generating a psuedo onEdit trigger event object. I was totally shocked to realize how easy it was to create it.

function onXdit(e) {
//function onEdit(e) {
  e.source.toast('Entry');
  console.log(JSON.stringify(e));
  const sh=e.range.getSheet();
  if(sh.getName()=="Sheet2" && e.range.columnStart==4 && e.range.rowStart!=5 && e.value=="TRUE") {
    e.source.toast('Section 2');
    sh.getRange(1,1).setValue(JSON.stringify(e));
    e.range.offset(0,1).setValue('CheckBoxIsOff')
    e.range.setValue("FALSE");
  }
  if(sh.getName()=="Sheet2" && e.range.columnStart==4 && e.range.rowStart==5  && e.value=="TRUE") {
    e.source.toast('Section 2');
    sh.getRange(2,4,4,1).setValue(e.mode?"TRUE":"FALSE");
    //sh.getRange(5,4,1,1).setValue("FALSE");
    sh.getRange(2,5,4,1).setValue("");
  }
}

This is Sheet2 which the sheet that is to be connected to the onEdit tester

This is Sheet2 after pressing the Run OnXdit Button

It does exactly what I would have wanted the onEdit() with the same code to have done. I guess my big problem was thinking about it too much.

The image above is just a simple table for providing the appropriate event object for the onXdit() function.

Animation: