BHoM_Engine: Handle nulls

BHoM_Engine/Query/Geometry.cs

@@ -46,6 +46,12 @@ public static IGeometry IGeometry(this IBHoMObject obj)
 
         public static IGeometry Geometry(this CustomObject obj)
         {
+            if(obj == null)
+            {
+                BH.Engine.Reflection.Compute.RecordError("Cannot query the geometry of a null custom object.");
+                return null;
+            }
+
             List<IGeometry> geometries = new List<IGeometry>();
 
             foreach (object item in obj.CustomData.Values)

BHoM_Engine/Query/Geometry3D.cs

@@ -53,6 +53,12 @@ public static IGeometry IGeometry3D(this IObject obj)
 
         public static IGeometry Geometry3D(this CustomObject obj)
         {
+            if(obj == null)
+            {
+                BH.Engine.Reflection.Compute.RecordError("Cannot query the 3D Geometry of a null custom object.");
+                return null;
+            }
+
             List<IGeometry> geometries = new List<IGeometry>();
 
             foreach (object item in obj.CustomData.Values)

BHoM_Engine/Query/GetAllFragments.cs

@@ -43,6 +43,9 @@ public static partial class Query
         [Output("fragmentList", "A deep copy of the fragments is returned for immutability.")]
         public static List<IFragment> GetAllFragments(this IBHoMObject iBHoMObject, Type parentType = null)
         {
+            if (iBHoMObject == null)
+                return new List<IFragment>();
+
             List<IFragment> fragments = new List<IFragment>();
 
             if (parentType == null)

BHoM_Engine/Query/Hash.cs

@@ -51,6 +51,12 @@ public static partial class Query
         [Input("hashFromFragment", "If true, if the object is a BHoMObject storing a HashFragment, retrieve the hash from it instead of computing the hash.")]
         public static string Hash(this IObject iObj, ComparisonConfig comparisonConfig = null, bool hashFromFragment = false)
         {
+            if(iObj == null)
+            {
+                BH.Engine.Reflection.Compute.RecordError("Cannot query the hash of a null object.");
+                return "";
+            }
+
             if (hashFromFragment && iObj is IBHoMObject)
             {
                 // Instead of computing the Hash, first tryGet the hash in HashFragment

BHoM_Engine/Query/UniquenessRestrictions.cs

@@ -41,6 +41,9 @@ public static partial class Query
         [Input("type", "The type of object you want to apply the fragment to.")]
         public static List<Type> UniquenessRestrictions(this Type type)
         {
+            if (type == null)
+                return new List<Type>();
+
             // Do not cover value types
             if (type.IsValueType)
                 return new List<Type>();