appendRow returns [Ljava.lang.Object;@ instead of values

Question

I want to copy form submissions over to a different sheet so that the copied data can be edited without affecting the original submissions.

I have the following code:

function copy2(){
  var responses = SpreadsheetApp.getActiveSpreadsheet().getSheetByName("from");
  var tracker =  SpreadsheetApp.getActiveSpreadsheet().getSheetByName("to");
  var lastrow = responses.getLastRow();
  var col = responses.getLastColumn();
  var row = responses.getRange(lastrow, 1, 1, col).getValues();

  tracker.appendRow([null,row[0]]);

Using null in appendRow helps you move the info over to the next column. However, it doesn't quite work with the row[0] array. If I remove the null it works fine, but I want the info copied on a column different that the first one.

Answer 1

Why Ljava.lang.Object?

Because you are using the older Rhino runtime that was written in Java. Hence when something unexpected happens you get a glimpse of the infrastructure GAS is built upon. Now, the java.lang.object is a base class in Java from which other objects, including arrays, are derived.

Since the appendRow method signature's only parameter accepts a one-dimensional array of values, your row[0], which contains an array (see what getvalues method returns), made it to the sheet as a string tag indicating that this was an object at runtime.

What to do in Rhino?

All solutions depend on taking [ null ] as your base array and using concat to append the rest of the first row, something like this: [ null ].concat(row[0]). You can also use push with a simple for loop for better performance.

What to do in V8⁰?

As the other answer mentioned, your best bet is the spread syntax. You can also do a push(...row[0]) to avoid concatenation of arrays (since you immediately use and discard the copy resulting from [ null, ...row[0] ]).

---

⁰ See official docs on how to migrate to V8 to take advantage of new language features and improved speed.