Initial commit (history squashed)

src/StellaOps.Feedser.Merge.Tests/TestLogger.cs

@@ -0,0 +1,52 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using Microsoft.Extensions.Logging;
+
+namespace StellaOps.Feedser.Merge.Tests;
+
+internal sealed class TestLogger<T> : ILogger<T>
+{
+    private static readonly IDisposable NoopScope = new DisposableScope();
+
+    public List<LogEntry> Entries { get; } = new();
+
+    public IDisposable BeginScope<TState>(TState state)
+        where TState : notnull
+        => NoopScope;
+
+    public bool IsEnabled(LogLevel logLevel) => true;
+
+    public void Log<TState>(LogLevel logLevel, EventId eventId, TState state, Exception? exception, Func<TState, Exception?, string> formatter)
+    {
+        if (formatter is null)
+        {
+            throw new ArgumentNullException(nameof(formatter));
+        }
+
+        IReadOnlyList<KeyValuePair<string, object?>>? structuredState = null;
+        if (state is IReadOnlyList<KeyValuePair<string, object?>> list)
+        {
+            structuredState = list.ToArray();
+        }
+        else if (state is IEnumerable<KeyValuePair<string, object?>> enumerable)
+        {
+            structuredState = enumerable.ToArray();
+        }
+
+        Entries.Add(new LogEntry(logLevel, eventId, formatter(state, exception), structuredState));
+    }
+
+    internal sealed record LogEntry(
+        LogLevel Level,
+        EventId EventId,
+        string Message,
+        IReadOnlyList<KeyValuePair<string, object?>>? StructuredState);
+
+    private sealed class DisposableScope : IDisposable
+    {
+        public void Dispose()
+        {
+        }
+    }
+}