How do you dynamically add multiple URLs into rich text for Google Sheets using Google Apps Script?

I have multiple links to Google Drive files in an array. I need to get the links into this format in the cell:

File 1, File 2, File 3

The links should be "File 1", "File 2" and "File 3".

The number of links is not the same in each row and I can't figure out is how to dynamically add the correct number of links. The links are coming from Google Form submissions. This is what I have:

var fileList = ["www.link1.com", "www.link2.com", "www.link3.com"];  var richText = "";  for (l = 0; l < fileList.length; l++) {    if (l == 0) {      var text = "File " + l;      var newRichText = SpreadsheetApp.newRichTextValue()        .setText(text)        .setLinkUrl(0, text.length, fileList[l])        .build();    } else {      var text = ", File " + l;      var newRichText = SpreadsheetApp.newRichTextValue()        .setText(text)        .setLinkUrl(richText.length+2, text.length, fileList[l])        .build();    }    richText = richText + newRichText;

Also tried for loops in the middle of the RichTextValueBuilder thing and there's also a copy() thing but neither worked for me. Those bits of code were gone hours ago so I can't post them here.

I'm not really that good at JS so it's possible I'm making a basic mistake.