first commit

NitroxModel/Helper/Validate.cs

@@ -0,0 +1,57 @@
+extern alias JB;
+using System;
+using System.Runtime.CompilerServices;
+using JB::JetBrains.Annotations;
+using NitroxModel.DataStructures.Util;
+
+namespace NitroxModel.Helper;
+
+public static class Validate
+{
+    // "where T : class" prevents non-nullable valuetypes from getting boxed to objects.
+    // In other words: Error when trying to assert non-null on something that can't be null in the first place.
+    [ContractAnnotation("o:null => halt")]
+    public static void NotNull<T>(T o, [CallerArgumentExpression("o")] string argumentExpression = null) where T : class
+    {
+        if (o != null)
+        {
+            return;
+        }
+
+        throw new ArgumentNullException(argumentExpression);
+    }
+
+    public static void IsTrue(bool b, [CallerArgumentExpression("b")] string argumentExpression = null)
+    {
+        if (!b)
+        {
+            throw new ArgumentException(argumentExpression);
+        }
+    }
+
+    public static void IsFalse(bool b, [CallerArgumentExpression("b")] string argumentExpression = null)
+    {
+        if (b)
+        {
+            throw new ArgumentException(argumentExpression);
+        }
+    }
+
+    public static T IsPresent<T>(Optional<T> opt) where T : class
+    {
+        if (!opt.HasValue)
+        {
+            throw new OptionalEmptyException<T>();
+        }
+        return opt.Value;
+    }
+
+    public static T IsPresent<T>(Optional<T> opt, string message) where T : class
+    {
+        if (!opt.HasValue)
+        {
+            throw new OptionalEmptyException<T>(message);
+        }
+        return opt.Value;
+    }
+}