Using flat() on array works only during debugging, otherwise getting error

[Kamil Tamaka]

Hello,

I encounter with following problem. Let's assume code. It grabbs data from M2:M, and filter empty rows.

function foo() {

  var sheet = SpreadsheetApp.getActiveSheet();

  var row = 2;

  var column = 13;

  var data;

  data = sheet.getRange(row, column, sheet.getLastRow() - 1).getValues().flat().filter(Boolean);

}

When I debug code, it looks pretty nice. Empty rows are filtered and instead hundreds of rows, only filled shows:

However, when I run that function, I am getting "TypeError: The flat function could not be found in the object" (translated, despite English on Google services, errors shows in my national language for unkown reason).

I noticed this issue when I wanted to receive data using POST it shown as response.

Why does it only happen during execution, not debugging? How can I fix it?
Thank you in advance.

[Dametrius King]

I see from the first screenshot that you're using the Rhino runtime. Do you get the same error when you Enable Chrome V8 runtime?

[Kamil Tamaka]

Oh, I didn't notice it might be caused by the Rhino rountime. I though flat() is not part of that engine.
Meanwhile I made workaround for myself:

     data = sheet.getRange(row, column, sheet.getLastRow() - 1).getValues().filter(function(row) {

      return row[0] !== '';

    });

which got the job done.

However, I enabled it tested and code works now with flat(). Thank you for fast answer :)