// Runs jest with the arguments it is given, and fails the run at once when a
// test left a timer or another open handle running. Such a handle keeps this
// process alive after the last test, so the run would hang. Jest itself only
// prints a warning one second after the run, and then keeps waiting. The test
// scripts in package.json run jest through this file, in this one process.
//
// Jest runs inside this process and writes to the terminal directly, so its
// output looks the same as a plain jest run. This file only checks each write
// to stderr for the warning below.

"use strict";

// The start of the warning that jest prints on stderr when the process has not
// exited one second after the test run.
const OPEN_HANDLE_WARNING =
    "Jest did not exit one second after the test run has completed.";

const writeStderr = process.stderr.write.bind(process.stderr);
process.stderr.write = (chunk, ...rest) => {
    const written = writeStderr(chunk, ...rest);
    if (String(chunk).includes(OPEN_HANDLE_WARNING)) {
        writeStderr(
            "script/lib/jest.js: failing the run, because a test left a " +
                "timer or another open handle running.\n",
        );
        process.exit(1);
    }
    return written;
};

// Jest's own command-line program. It reads its arguments from process.argv.
require("jest/bin/jest");