SAVEPOINT

Src/FluentAssertions/AssertionEngine.cs

@@ -0,0 +1,86 @@
+using System;
+using System.Linq;
+using System.Reflection;
+using FluentAssertions.Extensibility;
+using JetBrains.Annotations;
+
+namespace FluentAssertions;
+
+public static class AssertionEngine
+{
+    private static readonly object Lockable = new();
+    private static bool isInitialized;
+
+    static AssertionEngine()
+    {
+        EnsureInitialized();
+    }
+
+    [PublicAPI]
+    public static void ResetToDefaults()
+    {
+        isInitialized = false;
+        EnsureInitialized();
+    }
+
+    internal static void EnsureInitialized()
+    {
+        if (isInitialized)
+        {
+            return;
+        }
+
+        lock (Lockable)
+        {
+            if (!isInitialized)
+            {
+                ExecuteCustomInitializers();
+            }
+        }
+    }
+
+    private static void ExecuteCustomInitializers()
+    {
+        var currentAssembly = Assembly.GetExecutingAssembly();
+        var currentAssemblyName = currentAssembly.GetName();
+
+        AssertionEngineInitializerAttribute[] attributes = [];
+
+        try
+        {
+            attributes = AppDomain.CurrentDomain
+                .GetAssemblies()
+                .Where(assembly => assembly != currentAssembly && !assembly.IsDynamic && !IsFramework(assembly))
+                .Where(a => a.GetReferencedAssemblies().Any(r => r.FullName == currentAssemblyName.FullName))
+                .SelectMany(a => a.GetCustomAttributes<AssertionEngineInitializerAttribute>())
+                .ToArray();
+        }
+        catch
+        {
+            // Just ignore any exceptions that might happen while trying to find the attributes
+        }
+
+        foreach (var attribute in attributes)
+        {
+            try
+            {
+                attribute.Initialize();
+            }
+            catch
+            {
+                // Just ignore any exceptions that might happen while trying to find the attributes
+            }
+        }
+    }
+
+    private static bool IsFramework(Assembly assembly)
+    {
+#if NET6_0_OR_GREATER
+        return assembly!.FullName?.StartsWith("Microsoft.", StringComparison.OrdinalIgnoreCase) == true ||
+            assembly.FullName?.StartsWith("System.", StringComparison.OrdinalIgnoreCase) == true;
+#else
+        return assembly.FullName.StartsWith("Microsoft.", StringComparison.OrdinalIgnoreCase) ||
+            assembly.FullName.StartsWith("System.", StringComparison.OrdinalIgnoreCase);
+#endif
+    }
+}