tests.js

const whileHeapList = () => {
	var heapNode = null;
	var currTimestamp = null;
	var nextMinTimestamp = null;
	if (minheap.heapList.length) {
		heapNode = minheap.popMin();
		currTimestamp = heapNode['ts'];
		printer.print(heapNode.data);
		nextMinTimestamp = minheap.getPeakTimestamp();
		const whileCurrTimestampLTENextMinTimestamp = () => {
			if (currTimestamp <= nextMinTimestamp) {
				logSources[heapNode['source']].popAsync().then(log => {
					if (log) {
						let logtime = log.date.getTime();
						if (logtime <= nextMinTimestamp) {
							printer.print(log);
							currTimestamp = logtime;
						} else {
							minheap.insert({
								ts: logtime,
								source: heapNode["source"],
								data: log
							});
						}
						setTimeout(whileHeapList ,0);
					}
				}).catch(err => {
					console.log(err);
					console.log(err.stack);
				});
				// continue iteration
				setTimeout(whileCurrTimestampLTENextMinTimestamp, 0);
			}
		};
		// first iteration of whileCurrTimestampLTENextMinTimestamp
		whileCurrTimestampLTENextMinTimestamp();
		// continue iteration
		setTimeout(whileHeapList, 0)
	} else {
		console.log('Drained: ' + heapNode['source']);
		heapNode = minheap.popMin();
		printer.print(heapNode.data);
		currTimestamp = heapNode['ts'];
		if (minheap.heapList.length) {
			nextMinTimestamp = minheap.getPeakTimestamp();
		} else {
			const whileTrue = () => {
				logSources[heapNode['source']].popAsync().then(m => {
					if (m) {
						printer.print(m);
						setTimeout(whileTrue, 0);
					} else {
						console.log('Drained: ' + heapNode['source']);
					}
				});
			};
			// first iteration of whileTrue
			setTimeout(whileTrue, 0);
		}
	}
};
// first iteration of whileHeapList
whileHeapList();