public void UpdateFileTimeFromEntry_FileBusyForShortTime_Retries()
{
// Arrange
string tempFile = Path.GetTempFileName();
using CancellationTokenSource cts = new();
FileStream fileStream = null;
try
{
// At the time this test was written, UpdateFileTimeFromEntry's retry delay is exponential, with the max retries waiting
// Math.Pow(2, MaxRetries) - 1 milliseconds. Given this test depends on timing of multiple tasks that are not synchronised,
// this test is at high risk of being flakey, especially when tests are run in parallel, meaning the CPU is busy and might
// not run continuations as soon as they're ready. Therefore, use 13 retries so retries keep happening for about 8.2 seconds
// which should be plenty given the simulated AV locks the file for only 5 milliseconds + task scheduling latency.
Mock <IEnvironmentVariableReader> environmentVariableReader = new Mock <IEnvironmentVariableReader>();
environmentVariableReader.Setup(x => x.GetEnvironmentVariable("NUGET_UPDATEFILETIME_MAXRETRIES"))
.Returns("13");
ZipArchiveExtensions.Testable zipArchiveExtensions = new ZipArchiveExtensions.Testable(environmentVariableReader.Object);
using MemoryStream memoryStream = new();
using ZipArchive zipArchive = new(memoryStream, ZipArchiveMode.Create);
ZipArchiveEntry zipEntry = zipArchive.CreateEntry("test.file");
DateTime expectedTime = DateTime.UtcNow.AddHours(-5);
zipEntry.LastWriteTime = expectedTime;
fileStream = File.Open(tempFile, FileMode.Open, FileAccess.Read, FileShare.Read | FileShare.Delete);
Task avSimulation = Task.Run(async() =>
{
await Task.Delay(5, cts.Token);
fileStream.Dispose();
});
// Act
zipArchiveExtensions.UpdateFileTimeFromEntry(zipEntry, tempFile, NullLogger.Instance);
// Assert
DateTime fileLastWriteTime = File.GetLastWriteTimeUtc(tempFile);
Assert.Equal(expectedTime, fileLastWriteTime);
}
finally
{
fileStream?.Dispose();
cts.Cancel();
File.Delete(tempFile);
}
}
public async Task UpdateFileTimeFromEntry_FileBusyForLongTime_Throws()
{
// Arrange
string tempFile = Path.GetTempFileName();
try
{
Mock <IEnvironmentVariableReader> environmentVariableReader = new Mock <IEnvironmentVariableReader>();
ZipArchiveExtensions.Testable zipArchiveExtensions = new ZipArchiveExtensions.Testable(environmentVariableReader.Object);
using MemoryStream memoryStream = new();
using ZipArchive zipArchive = new(memoryStream, ZipArchiveMode.Create);
ZipArchiveEntry zipEntry = zipArchive.CreateEntry("test.file");
DateTime expectedTime = DateTime.UtcNow.AddHours(-5);
zipEntry.LastWriteTime = expectedTime;
using FileStream fileStream = File.Open(tempFile, FileMode.Open, FileAccess.Read, FileShare.Read | FileShare.Delete);
// Act & Assert
await Assert.ThrowsAsync <IOException>(async() =>
{
Task task = Task.Run(() => zipEntry.UpdateFileTimeFromEntry(tempFile, NullLogger.Instance));
// If the above deadlocks until the file is unlocked, then we need another way to fail the test within a reasonable time.
using CancellationTokenSource cts = new();
Task delay = Task.Delay(TimeSpan.FromSeconds(10), cts.Token);
var completed = await Task.WhenAny(task, delay);
cts.Cancel();
if (completed == delay)
{
throw new TimeoutException();
}
await completed;
});
}
finally
{
File.Delete(tempFile);
}
}
