SystemExtensions/SystemExtensions.DependencyInjection.Tests/Logging/CVLoggerTests.cs

using FluentAssertions;
using Microsoft.Extensions.Logging;
using Microsoft.VisualStudio.TestTools.UnitTesting;
using Moq;
using System;
using System.Logging;

namespace SystemExtensions.DependencyInjection.Tests.Logging
{
    [TestClass]
    public class CVLoggerTests
    {
        private readonly Mock<ICVLoggerProvider> cvLoggerProviderMock = new();
        private CVLogger cVLogger;

        [TestInitialize]
        public void TestInitialize()
        {
            this.cVLogger = new CVLogger(string.Empty, this.cvLoggerProviderMock.Object);
        }

        [TestMethod]
        public void BeginScope_ReturnsNull()
        {
            var scope = this.cVLogger.BeginScope(string.Empty);

            scope.Should().BeNull();
        }

        [TestMethod]
        [DataRow(LogLevel.Debug)]
        [DataRow(LogLevel.Trace)]
        [DataRow(LogLevel.Information)]
        [DataRow(LogLevel.Warning)]
        [DataRow(LogLevel.Error)]
        [DataRow(LogLevel.Critical)]
        public void IsEnabled_OnAllLogLevels_ReturnsTrue(LogLevel logLevel)
        {
            var enabled = this.cVLogger.IsEnabled(logLevel);

            enabled.Should().BeTrue();
        }

        [TestMethod]
        public void Log_CallsFormatter()
        {
            var called = false;
            Func<string, Exception, string> messageFormatter = new((state, exception) =>
            {
                called = true;
                return string.Empty;
            });

            this.cVLogger.Log(LogLevel.Debug, new EventId(), "Some message", new Exception(), messageFormatter);

            called.Should().BeTrue();
        }

        [TestMethod]
        public void Log_CallsLogsProvider()
        {
            this.SetupLoggerProvider();

            this.cVLogger.Log(LogLevel.Debug, new EventId(), "Some message", new Exception(), new Func<string, Exception, string>((s, e) => string.Empty));

            this.cvLoggerProviderMock.Verify();
        }

        private void SetupLoggerProvider()
        {
            this.cvLoggerProviderMock
                .Setup(u => u.LogEntry(It.IsAny<Log>()))
                .Verifiable();
        }
    }
}