Script to convert Zotero items from Journal Article to Preprint.

arxiv.js

/*
 * Previously, preprints were added to Zotero as items of the "Journal Article"
 * type, but it now has a dedicated "Preprint" item type. This script finds all
 * articles that look like arXiv preprints and converts them to the new type. If
 * your items have categories in the publication name, you may need to remove
 * them.
 *
 * Select all the articles you want to convert, go to Tools -> Developer -> Run
 * JavaScript, check "Run as async function", paste this script on the left side,
 * and press "Run". It may take a while, but eventually the right side should
 * display a summary of all the affected items.
 *
 * There doesn't appear to be any way to undo this process, so you should make a
 * backup of your library, and test this script on a single article first.
 */

const selectedItems = ZoteroPane.getSelectedItems();
const titles = [];

for (const item of selectedItems) {
    if (item.getType() != Zotero.ItemTypes.getID('journalArticle')) {
        continue;
    }

    if (!item.getField('publicationTitle').startsWith('arXiv:')) {
        continue;
    }

    const archive_id = item.getField('publicationTitle');
    item.setType(Zotero.ItemTypes.getID('preprint'));
    item.setField('repository', 'arXiv');
    item.setField('archiveID', archive_id);
    await item.saveTx();

    titles.push(archive_id + ': ' + item.getField('title'));
}

return titles.join('\n');