log4js-node/test/tap/recordingAppender-test.js

const { test } = require("tap");
const log4js = require("../../lib/log4js");

test("recording appender", t => {
  log4js.configure({
    appenders: { rec: { type: 'recording' } },
    categories: { default: { appenders: [ 'rec' ], 'level': 'debug' } }
  });

  const logger = log4js.getLogger();
  logger.level = 'debug';
  logger.debug('This will go to the recording!');
  logger.debug('Another one');

  const recording = log4js.recording();
  const loggingEvents = recording.playback();

  t.equal(loggingEvents.length, 2, "There should be 2 recorded events");
  t.equal(loggingEvents[0].data[0], "This will go to the recording!");
  t.equal(loggingEvents[1].data[0], "Another one");

  recording.reset();
  const loggingEventsPostReset = recording.playback();

  t.equal(loggingEventsPostReset.length, 0, "There should be 0 recorded events");

  t.end();
});