Exporting Multiple Artboards Names

I recently ran across this same issue and couldn't determine a way to set the name correctly before saving/exporting so I instead just rename the files after the save/export. The code below will export the artboard(s) you specify in the `artboardsToExport` array (0-index), then rename the exported file(s) to just "Artboad X.ai". The `baseName` variable is just so I know how to exactly recreate the path for renaming.

doc = app.activeDocument;
exportFiles("TEST");

function exportFiles(baseName) {
  var expOptions = new IllustratorSaveOptions();
  expOptions.flattenOutput = OutputFlattening.PRESERVEAPPEARANCE;
  expOptions.saveMultipleArtboards = true;

  var artboardsToExport = [1, 2];
  var ab, tempFile, finalFile, testFile;
  for (var i = 0; i < artboardsToExport.length; i++) {
    ab = doc.artboards[artboardsToExport[i]];

    // When exporting specific artboards, the api only allows specifying the first part of
    // the file name, then it appends `_Artboard Name` and add the extension which result in:
    //`{baseName}_Artboard X.{extension}`
    tempFile = new File(doc.path + "/" + baseName);

    // To be able to correctly name the exported file(s), I am recreating the known
    // naming convention with a new `file` object to that path
    finalFile = new File(doc.path + "/" + baseName + "_" + ab.name + ".ai");

    // Since the export exported file path and the preferred file path are different the built-in
    // file overwrite protection will not prompt you so and the `rename` method would not
    // overwrite the existing file. So, here I do the checking and prompt if needed.
    testFile = new File(doc.path + "/" + ab.name + ".ai");
    if (testFile.exists) {
      if (
        !Window.confirm(
          "File already exists!\nOverwrite " + ab.name + ".ai?",
          "noAsDflt",
          "File Already Exists"
        )
      ) {
        // If you choose not to overwrite I just remove the exported artboard
        finalFile.remove();
        continue;
      } else {
        // Otherwise, I remove the file at that path so the rename works
        testFile.remove();
      }
    }

    // Export the file
    expOptions.artboardRange = artboardsToExport[i] + 1 + "";
    doc.saveAs(tempFile, expOptions);

    // Rename the file
    finalFile.rename(ab.name + ".ai");
  }

  doc.close(SaveOptions.DONOTSAVECHANGES);
}