public void Purge()

in src/DependencyManagement/DependencySnapshotPurger.cs [64:105]
35 lines of code
4 McCabe index (conditional complexity)

        public void Purge(ILogger logger)
        {
            var allSnapshotPaths = _storage.GetInstalledAndInstallingSnapshots();

            var threshold = DateTime.UtcNow - _heartbeatPeriod - _oldHeartbeatAgeMargin;

            var pathSortedByAccessTime = allSnapshotPaths
                                            .Where(path => string.CompareOrdinal(path, _currentlyUsedSnapshotPath) != 0)
                                            .Select(path => Tuple.Create(path, GetSnapshotAccessTimeUtc(path, logger)))
                                            .OrderBy(entry => entry.Item2)
                                            .ToArray();

            var snapshotsLogmessage = string.Format(
                                        PowerShellWorkerStrings.LogDependencySnapshotsInstalledAndSnapshotsToKeep,
                                        pathSortedByAccessTime.Length,
                                        _minNumberOfSnapshotsToKeep);
            logger.Log(isUserOnlyLog: false, LogLevel.Trace, snapshotsLogmessage);

            for (var i = 0; i < pathSortedByAccessTime.Length - _minNumberOfSnapshotsToKeep; ++i)
            {
                var creationTime = pathSortedByAccessTime[i].Item2;
                if (creationTime > threshold)
                {
                    break;
                }

                var pathToRemove = pathSortedByAccessTime[i].Item1;

                try
                {
                    var message = string.Format(PowerShellWorkerStrings.RemovingDependenciesFolder, pathToRemove);
                    logger.Log(isUserOnlyLog: false, LogLevel.Trace, message);

                    _storage.RemoveSnapshot(pathToRemove);
                }
                catch (IOException e)
                {
                    var message = string.Format(PowerShellWorkerStrings.FailedToRemoveDependenciesFolder, pathToRemove, e.Message);
                    logger.Log(isUserOnlyLog: false, LogLevel.Warning, message, e);
                }
            }
        }