delete_stale_merged_branch.js

const clean = (timeToWait, includeAbandoned = false) => {
    if (!window.location.href.includes("/branches/stale")) {
        return;
    }
    const branches = () => Array.from(document.querySelectorAll("li.Box-row.js-branch-row"));
    const isMerged = (branch) => branch.querySelector("a.State.State--purple") !== null;
    const isClosed = (branch) => branch.querySelector("a.State.State--red") !== null;
    const isAbandoned = (branch) => branch.querySelector("a.btn.test-compare-link");
    const isMergedOrClosed = (branch) => isMerged(branch) || isClosed(branch);
    const isMergedClosedOrAbandoned = (branch) => isMergedOrClosed(branch) || isAbandoned(branch);
    const deleteBranch = branch => branch.querySelector("button.btn-link.js-branch-delete-target.text-red")?.click();
    const branchesToDelete = branches().filter(includeAbandoned ? isMergedClosedOrAbandoned : isMergedOrClosed);
    if (branchesToDelete.length === 0) {
        // go to page - 1
        const url = new URL(window.location.href);
        const page = parseInt(url.searchParams.get("page") ? url.searchParams.get("page") : "1", 10);
        if (page <= 0) {
            return;
        }
        url.searchParams.set("page", (page - 1).toString());
        window.location.href = url.href;
        return;
    }
    branchesToDelete.forEach(deleteBranch);
    setTimeout(() => {
        window.location.reload();
    }, timeToWait);
};
clean(3000, false);