Ability to scope the TestingLoggerFactory (#147)

src/NServiceBus.Testing.Tests/ApprovalFiles/APIApprovals.Approve.approved.txt

@@ -363,6 +363,7 @@ namespace NServiceBus.Testing
     public class TestingLoggerFactory : NServiceBus.Logging.LoggingFactoryDefinition
     {
         public TestingLoggerFactory() { }
+        public System.IDisposable BeginScope(System.IO.TextWriter writer, NServiceBus.Logging.LogLevel level = 0) { }
         protected override NServiceBus.Logging.ILoggerFactory GetLoggingFactory() { }
         public void Level(NServiceBus.Logging.LogLevel level) { }
         public void WriteTo(System.IO.TextWriter writer) { }

src/NServiceBus.Testing.Tests/Logging/LoggingForFixtureTests.cs

@@ -0,0 +1,50 @@
+namespace NServiceBus.Testing.Tests.Logging
+{
+    using System;
+    using System.IO;
+    using NServiceBus.Logging;
+    using NUnit.Framework;
+
+    [TestFixture]
+    [Parallelizable]
+    public class LoggingForFixtureTests
+    {
+        StringWriter writer;
+        IDisposable scope;
+
+        [SetUp]
+        public void Setup()
+        {
+            writer = new StringWriter();
+
+            this.scope = LogManager.Use<TestingLoggerFactory>()
+                .BeginScope(writer);
+        }
+
+        [Test]
+        public void Should_write_first_independent_from_other()
+        {
+            var Logger = LogManager.GetLogger<LoggingForFixtureTests>();
+            Logger.Debug("First");
+
+            StringAssert.Contains("NServiceBus.Testing.Tests.Logging.LoggingForFixtureTests First", writer.ToString());
+            StringAssert.DoesNotContain("NServiceBus.Testing.Tests.Logging.LoggingForFixtureTests Second", writer.ToString());
+        }
+
+        [Test]
+        public void Should_write_second_independent_from_other()
+        {
+            var Logger = LogManager.GetLogger<LoggingForFixtureTests>();
+            Logger.Debug("Second");
+
+            StringAssert.Contains("NServiceBus.Testing.Tests.Logging.LoggingForFixtureTests Second", writer.ToString());
+            StringAssert.DoesNotContain("NServiceBus.Testing.Tests.Logging.LoggingForFixtureTests First", writer.ToString());
+        }
+
+        [TearDown]
+        public void Teardown()
+        {
+            scope.Dispose();
+        }
+    }
+}

src/NServiceBus.Testing.Tests/Logging/LoggingTests.cs

@@ -0,0 +1,144 @@
+namespace NServiceBus.Testing.Tests.Logging
+{
+    using System;
+    using System.IO;
+    using NServiceBus.Logging;
+    using NUnit.Framework;
+
+    [TestFixture]
+    public class LoggingTests
+    {
+        [TearDown]
+        public void Teardown()
+        {
+            SomeClassThatUsesStaticLogger.Reset();
+        }
+
+        [Test]
+        public void Scoped_Writer_should_be_honored()
+        {
+            var firstStringWriter = new StringWriter();
+            var loggerFactory = LogManager.Use<TestingLoggerFactory>();
+            using (loggerFactory.BeginScope(firstStringWriter))
+            {
+                var firstInstance = new SomeClassThatUsesStaticLogger();
+                firstInstance.DoSomething();
+            }
+
+            var secondStringWriter = new StringWriter();
+            using (loggerFactory.BeginScope(secondStringWriter))
+            {
+                var secondInstance = new SomeClassThatUsesStaticLogger();
+                secondInstance.DoSomething();
+            }
+
+            var firstLogString = firstStringWriter.ToString();
+            var secondLogString = secondStringWriter.ToString();
+
+            Assert.AreNotEqual(firstLogString, secondLogString);
+            StringAssert.Contains("NServiceBus.Testing.Tests.Logging.LoggingTests+SomeClassThatUsesStaticLogger 0", firstLogString);
+            StringAssert.DoesNotContain("NServiceBus.Testing.Tests.Logging.LoggingTests+SomeClassThatUsesStaticLogger 1", firstLogString);
+            StringAssert.Contains("NServiceBus.Testing.Tests.Logging.LoggingTests+SomeClassThatUsesStaticLogger 1", secondLogString);
+            StringAssert.DoesNotContain("NServiceBus.Testing.Tests.Logging.LoggingTests+SomeClassThatUsesStaticLogger 0", secondLogString);
+        }
+
+        [Test]
+        public void Scoped_Loglevel_should_be_honored()
+        {
+            var firstStringWriter = new StringWriter();
+            var loggerFactory = LogManager.Use<TestingLoggerFactory>();
+            using (loggerFactory.BeginScope(firstStringWriter, LogLevel.Warn))
+            {
+                var firstInstance = new SomeClassThatUsesStaticLogger();
+                firstInstance.DoSomething();
+            }
+
+            var secondStringWriter = new StringWriter();
+            using (loggerFactory.BeginScope(secondStringWriter))
+            {
+                var secondInstance = new SomeClassThatUsesStaticLogger();
+                secondInstance.DoSomething();
+            }
+
+            var firstLogString = firstStringWriter.ToString();
+            var secondLogString = secondStringWriter.ToString();
+
+            Assert.AreNotEqual(firstLogString, secondLogString);
+            Assert.IsEmpty(firstLogString);
+            StringAssert.Contains("NServiceBus.Testing.Tests.Logging.LoggingTests+SomeClassThatUsesStaticLogger 1", secondLogString);
+        }
+
+        [Test]
+        public void Global_Writer_should_be_honored()
+        {
+            var loggerFactory = LogManager.Use<TestingLoggerFactory>();
+            var globalWriter = new StringWriter();
+            loggerFactory.WriteTo(globalWriter);
+
+            var firstInstance = new SomeClassThatUsesStaticLogger();
+            firstInstance.DoSomething();
+
+            var secondStringWriter = new StringWriter();
+            using (loggerFactory.BeginScope(secondStringWriter))
+            {
+                var secondInstance = new SomeClassThatUsesStaticLogger();
+                secondInstance.DoSomething();
+            }
+
+            var globalLogString = globalWriter.ToString();
+            var scopedLogString = secondStringWriter.ToString();
+
+            Assert.AreNotEqual(globalLogString, scopedLogString);
+            StringAssert.Contains("NServiceBus.Testing.Tests.Logging.LoggingTests+SomeClassThatUsesStaticLogger 0", globalLogString);
+            StringAssert.DoesNotContain("NServiceBus.Testing.Tests.Logging.LoggingTests+SomeClassThatUsesStaticLogger 1", globalLogString);
+            StringAssert.Contains("NServiceBus.Testing.Tests.Logging.LoggingTests+SomeClassThatUsesStaticLogger 1", scopedLogString);
+            StringAssert.DoesNotContain("NServiceBus.Testing.Tests.Logging.LoggingTests+SomeClassThatUsesStaticLogger 0", scopedLogString);
+        }
+
+        [Test]
+        public void Scope_cannot_be_nested()
+        {
+            Assert.Throws<InvalidOperationException>(() =>
+            {
+                var loggerFactory = LogManager.Use<TestingLoggerFactory>();
+                using (loggerFactory.BeginScope(new StringWriter()))
+                using (loggerFactory.BeginScope(new StringWriter()))
+                {
+                }
+            });
+        }
+
+        [Test]
+        public void NoScope_does_work()
+        {
+            LogManager.Use<TestingLoggerFactory>();
+
+            var secondInstance = new SomeClassThatUsesStaticLogger();
+            secondInstance.DoSomething();
+        }
+
+        class SomeClassThatUsesStaticLogger
+        {
+            public SomeClassThatUsesStaticLogger()
+            {
+                InstanceCounter = instanceCounter++;
+            }
+
+            public int InstanceCounter { get; }
+
+            public void DoSomething()
+            {
+                Logger.Debug(InstanceCounter.ToString());
+            }
+
+            public static void Reset()
+            {
+                instanceCounter = 0;
+            }
+
+            static int instanceCounter;
+
+            static ILog Logger = LogManager.GetLogger<SomeClassThatUsesStaticLogger>();
+        }
+    }
+}