test(logging): 添加采样过滤器和统计附加器的单元测试

- 为SamplingFilter添加完整的单元测试覆盖采样率、时间窗口、线程安全等功能
- 为StatisticsAppender添加全面的单元测试验证统计计算、错误率跟踪、报告生成功能
- 测试各个日志级别和记录器的独立状态维护
- 验证多线程环境下的数据一致性
- 包含边界条件和异常情况的测试用例

GFramework.Core.Tests/logging/SamplingFilterTests.cs

@@ -0,0 +1,133 @@
+using GFramework.Core.Abstractions.logging;
+using GFramework.Core.logging.filters;
+using NUnit.Framework;
+
+namespace GFramework.Core.Tests.logging;
+
+[TestFixture]
+public class SamplingFilterTests
+{
+    [Test]
+    public void SamplingFilter_Should_Sample_Logs_By_Rate()
+    {
+        var filter = new SamplingFilter(sampleRate: 3, timeWindow: TimeSpan.FromMinutes(1));
+        var entry = new LogEntry(
+            DateTime.UtcNow,
+            LogLevel.Info,
+            "TestLogger",
+            "Test message",
+            null,
+            null
+        );
+
+        // 前 3 条：第 1 条通过，第 2、3 条被过滤
+        Assert.That(filter.ShouldLog(entry), Is.True); // 1st
+        Assert.That(filter.ShouldLog(entry), Is.False); // 2nd
+        Assert.That(filter.ShouldLog(entry), Is.False); // 3rd
+
+        // 第 4 条通过（新周期）
+        Assert.That(filter.ShouldLog(entry), Is.True); // 4th
+        Assert.That(filter.ShouldLog(entry), Is.False); // 5th
+        Assert.That(filter.ShouldLog(entry), Is.False); // 6th
+    }
+
+    [Test]
+    public void SamplingFilter_Should_Reset_After_Time_Window()
+    {
+        var filter = new SamplingFilter(sampleRate: 2, timeWindow: TimeSpan.FromMilliseconds(100));
+        var entry = new LogEntry(
+            DateTime.UtcNow,
+            LogLevel.Info,
+            "TestLogger",
+            "Test message",
+            null,
+            null
+        );
+
+        // 第一个窗口
+        Assert.That(filter.ShouldLog(entry), Is.True); // 1st
+        Assert.That(filter.ShouldLog(entry), Is.False); // 2nd
+
+        // 等待时间窗口过期
+        Thread.Sleep(150);
+
+        // 新窗口应该重置计数
+        Assert.That(filter.ShouldLog(entry), Is.True); // 1st in new window
+        Assert.That(filter.ShouldLog(entry), Is.False); // 2nd in new window
+    }
+
+    [Test]
+    public void SamplingFilter_Should_Maintain_Separate_State_Per_Logger()
+    {
+        var filter = new SamplingFilter(sampleRate: 2, timeWindow: TimeSpan.FromMinutes(1));
+
+        var entry1 = new LogEntry(DateTime.UtcNow, LogLevel.Info, "Logger1", "Message", null, null);
+        var entry2 = new LogEntry(DateTime.UtcNow, LogLevel.Info, "Logger2", "Message", null, null);
+
+        // Logger1 的第一条
+        Assert.That(filter.ShouldLog(entry1), Is.True);
+
+        // Logger2 的第一条（独立计数）
+        Assert.That(filter.ShouldLog(entry2), Is.True);
+
+        // Logger1 的第二条
+        Assert.That(filter.ShouldLog(entry1), Is.False);
+
+        // Logger2 的第二条
+        Assert.That(filter.ShouldLog(entry2), Is.False);
+    }
+
+    [Test]
+    public void SamplingFilter_Should_Throw_When_SampleRate_Is_Invalid()
+    {
+        Assert.Throws<ArgumentException>(() =>
+        {
+            new SamplingFilter(sampleRate: 0, timeWindow: TimeSpan.FromMinutes(1));
+        });
+
+        Assert.Throws<ArgumentException>(() =>
+        {
+            new SamplingFilter(sampleRate: -1, timeWindow: TimeSpan.FromMinutes(1));
+        });
+    }
+
+    [Test]
+    public void SamplingFilter_Should_Throw_When_TimeWindow_Is_Invalid()
+    {
+        Assert.Throws<ArgumentException>(() => { new SamplingFilter(sampleRate: 2, timeWindow: TimeSpan.Zero); });
+
+        Assert.Throws<ArgumentException>(() =>
+        {
+            new SamplingFilter(sampleRate: 2, timeWindow: TimeSpan.FromSeconds(-1));
+        });
+    }
+
+    [Test]
+    public void SamplingFilter_Should_Be_Thread_Safe()
+    {
+        var filter = new SamplingFilter(sampleRate: 10, timeWindow: TimeSpan.FromMinutes(1));
+        var entry = new LogEntry(DateTime.UtcNow, LogLevel.Info, "TestLogger", "Message", null, null);
+
+        var passedCount = 0;
+        var tasks = new List<Task>();
+
+        for (int i = 0; i < 10; i++)
+        {
+            tasks.Add(Task.Run(() =>
+            {
+                for (int j = 0; j < 100; j++)
+                {
+                    if (filter.ShouldLog(entry))
+                    {
+                        Interlocked.Increment(ref passedCount);
+                    }
+                }
+            }));
+        }
+
+        Task.WaitAll(tasks.ToArray());
+
+        // 1000 条日志，采样率 10，应该通过约 100 条
+        Assert.That(passedCount, Is.InRange(90, 110));
+    }
+}

GFramework.Core.Tests/logging/StatisticsAppenderTests.cs

@@ -0,0 +1,186 @@
+using GFramework.Core.Abstractions.logging;
+using GFramework.Core.logging.appenders;
+using NUnit.Framework;
+
+namespace GFramework.Core.Tests.logging;
+
+[TestFixture]
+public class StatisticsAppenderTests
+{
+    [SetUp]
+    public void SetUp()
+    {
+        _appender = new StatisticsAppender();
+    }
+
+    [TearDown]
+    public void TearDown()
+    {
+    }
+
+    private StatisticsAppender _appender = null!;
+
+    [Test]
+    public void StatisticsAppender_Should_Count_Total_Logs()
+    {
+        var entry = CreateLogEntry(LogLevel.Info, "TestLogger", "Message");
+
+        _appender.Append(entry);
+        _appender.Append(entry);
+        _appender.Append(entry);
+
+        Assert.That(_appender.TotalCount, Is.EqualTo(3));
+    }
+
+    [Test]
+    public void StatisticsAppender_Should_Count_Errors()
+    {
+        _appender.Append(CreateLogEntry(LogLevel.Info, "Logger", "Info"));
+        _appender.Append(CreateLogEntry(LogLevel.Error, "Logger", "Error"));
+        _appender.Append(CreateLogEntry(LogLevel.Fatal, "Logger", "Fatal"));
+        _appender.Append(CreateLogEntry(LogLevel.Warning, "Logger", "Warning"));
+
+        Assert.That(_appender.ErrorCount, Is.EqualTo(2)); // Error + Fatal
+        Assert.That(_appender.TotalCount, Is.EqualTo(4));
+    }
+
+    [Test]
+    public void StatisticsAppender_Should_Calculate_Error_Rate()
+    {
+        _appender.Append(CreateLogEntry(LogLevel.Info, "Logger", "Info"));
+        _appender.Append(CreateLogEntry(LogLevel.Error, "Logger", "Error"));
+        _appender.Append(CreateLogEntry(LogLevel.Info, "Logger", "Info"));
+        _appender.Append(CreateLogEntry(LogLevel.Info, "Logger", "Info"));
+
+        // 1 error out of 4 total = 0.25
+        Assert.That(_appender.ErrorRate, Is.EqualTo(0.25).Within(0.001));
+    }
+
+    [Test]
+    public void StatisticsAppender_Should_Count_By_Level()
+    {
+        _appender.Append(CreateLogEntry(LogLevel.Info, "Logger", "Info1"));
+        _appender.Append(CreateLogEntry(LogLevel.Info, "Logger", "Info2"));
+        _appender.Append(CreateLogEntry(LogLevel.Error, "Logger", "Error"));
+        _appender.Append(CreateLogEntry(LogLevel.Warning, "Logger", "Warning"));
+
+        Assert.That(_appender.GetCountByLevel(LogLevel.Info), Is.EqualTo(2));
+        Assert.That(_appender.GetCountByLevel(LogLevel.Error), Is.EqualTo(1));
+        Assert.That(_appender.GetCountByLevel(LogLevel.Warning), Is.EqualTo(1));
+        Assert.That(_appender.GetCountByLevel(LogLevel.Debug), Is.EqualTo(0));
+    }
+
+    [Test]
+    public void StatisticsAppender_Should_Count_By_Logger()
+    {
+        _appender.Append(CreateLogEntry(LogLevel.Info, "Logger1", "Message"));
+        _appender.Append(CreateLogEntry(LogLevel.Info, "Logger1", "Message"));
+        _appender.Append(CreateLogEntry(LogLevel.Info, "Logger2", "Message"));
+
+        Assert.That(_appender.GetCountByLogger("Logger1"), Is.EqualTo(2));
+        Assert.That(_appender.GetCountByLogger("Logger2"), Is.EqualTo(1));
+        Assert.That(_appender.GetCountByLogger("Logger3"), Is.EqualTo(0));
+    }
+
+    [Test]
+    public void StatisticsAppender_Should_Track_Uptime()
+    {
+        var startTime = _appender.StartTime;
+        Thread.Sleep(100);
+
+        Assert.That(_appender.Uptime, Is.GreaterThanOrEqualTo(TimeSpan.FromMilliseconds(100)));
+        Assert.That(_appender.StartTime, Is.EqualTo(startTime));
+    }
+
+    [Test]
+    public void StatisticsAppender_Should_Reset_Statistics()
+    {
+        _appender.Append(CreateLogEntry(LogLevel.Info, "Logger", "Message"));
+        _appender.Append(CreateLogEntry(LogLevel.Error, "Logger", "Error"));
+
+        Assert.That(_appender.TotalCount, Is.EqualTo(2));
+        Assert.That(_appender.ErrorCount, Is.EqualTo(1));
+
+        var oldStartTime = _appender.StartTime;
+        Thread.Sleep(10);
+        _appender.Reset();
+
+        Assert.That(_appender.TotalCount, Is.EqualTo(0));
+        Assert.That(_appender.ErrorCount, Is.EqualTo(0));
+        Assert.That(_appender.GetLevelCounts().Count, Is.EqualTo(0));
+        Assert.That(_appender.GetLoggerCounts().Count, Is.EqualTo(0));
+        Assert.That(_appender.StartTime, Is.GreaterThan(oldStartTime));
+    }
+
+    [Test]
+    public void StatisticsAppender_Should_Generate_Report()
+    {
+        _appender.Append(CreateLogEntry(LogLevel.Info, "Logger1", "Info"));
+        _appender.Append(CreateLogEntry(LogLevel.Error, "Logger2", "Error"));
+        _appender.Append(CreateLogEntry(LogLevel.Warning, "Logger1", "Warning"));
+
+        var report = _appender.GenerateReport();
+
+        Assert.That(report, Does.Contain("总日志数: 3"));
+        Assert.That(report, Does.Contain("错误日志数: 1"));
+        Assert.That(report, Does.Contain("Info"));
+        Assert.That(report, Does.Contain("Error"));
+        Assert.That(report, Does.Contain("Warning"));
+        Assert.That(report, Does.Contain("Logger1"));
+        Assert.That(report, Does.Contain("Logger2"));
+    }
+
+    [Test]
+    public void StatisticsAppender_Should_Return_Empty_Collections_When_No_Data()
+    {
+        Assert.That(_appender.TotalCount, Is.EqualTo(0));
+        Assert.That(_appender.ErrorCount, Is.EqualTo(0));
+        Assert.That(_appender.ErrorRate, Is.EqualTo(0));
+        Assert.That(_appender.GetLevelCounts().Count, Is.EqualTo(0));
+        Assert.That(_appender.GetLoggerCounts().Count, Is.EqualTo(0));
+    }
+
+    [Test]
+    public void StatisticsAppender_Should_Be_Thread_Safe()
+    {
+        var tasks = new List<Task>();
+
+        for (int i = 0; i < 10; i++)
+        {
+            var loggerId = i;
+            tasks.Add(Task.Run(() =>
+            {
+                for (int j = 0; j < 100; j++)
+                {
+                    var level = j % 2 == 0 ? LogLevel.Info : LogLevel.Error;
+                    _appender.Append(CreateLogEntry(level, $"Logger{loggerId}", "Message"));
+                }
+            }));
+        }
+
+        Task.WaitAll(tasks.ToArray());
+
+        Assert.That(_appender.TotalCount, Is.EqualTo(1000));
+        Assert.That(_appender.ErrorCount, Is.EqualTo(500));
+        Assert.That(_appender.GetCountByLevel(LogLevel.Info), Is.EqualTo(500));
+        Assert.That(_appender.GetCountByLevel(LogLevel.Error), Is.EqualTo(500));
+    }
+
+    [Test]
+    public void Flush_Should_Not_Throw()
+    {
+        Assert.DoesNotThrow(() => _appender.Flush());
+    }
+
+    private static LogEntry CreateLogEntry(LogLevel level, string loggerName, string message)
+    {
+        return new LogEntry(
+            DateTime.UtcNow,
+            level,
+            loggerName,
+            message,
+            null,
+            null
+        );
+    }
+}