Minor fixes

Author: arimger

Assets/Editor Toolbox/Editor/Drawers/Regular/FormattedNumberAttributeDrawer.cs

@@ -55,7 +55,11 @@ protected override void OnGUISafe(Rect position, SerializedProperty property, GU
             }
             else
             {
+#if UNITY_2019_2_OR_NEWER
                 position.xMin += EditorGUIUtility.labelWidth + EditorGUIUtility.standardVerticalSpacing;
+#else
+                position.xMin += EditorGUIUtility.labelWidth;
+#endif
             }
 
             var targetAttribute = attribute as FormattedNumberAttribute;

Assets/Editor Toolbox/Editor/Internal/TypeConstraintContext.cs

@@ -16,7 +16,13 @@ public TypeConstraintContext(Type targetType)
 
         public virtual bool IsSatisfied(Type type)
         {
+#if UNITY_2019_2_OR_NEWER
             return type.IsVisible;
+#else
+            return type.IsVisible && (targetType.IsGenericType
+                ? targetType.IsAssignableFromGeneric(type)
+                : targetType.IsAssignableFrom(type));
+#endif
         }
 
         public virtual void ApplyTarget(Type type)

Assets/Editor Toolbox/Editor/Internal/TypeConstraintStandard.cs

@@ -22,7 +22,7 @@ public override bool IsSatisfied(Type type)
             return base.IsSatisfied(type) &&
                 //NOTE: consider moving allowAbstract && allowObsolete properties to the TypeSettings enum
                 (!type.IsClass || Settings.HasFlag(TypeSettings.Class)) &&
-                (!type.IsAbstract || Settings.HasFlag(TypeSettings.Interface) || AllowAbstract) &&
+                (!type.IsAbstract || (Settings.HasFlag(TypeSettings.Interface) && type.IsInterface) || AllowAbstract) &&
                 (!type.IsInterface || Settings.HasFlag(TypeSettings.Interface)) &&
                 (!Attribute.IsDefined(type, typeof(ObsoleteAttribute)) || AllowObsolete);
         }

Assets/Editor Toolbox/Editor/Utilities/TypeUtilities.cs

@@ -1,6 +1,7 @@
 using System;
 using System.Collections.Generic;
 using System.Linq;
+using System.Reflection;
 
 using UnityEditor;
 
@@ -42,20 +43,7 @@ public static TypesCachedCollection GetCollection(TypeConstraintContext constrai
                 return new TypesCachedCollection();
             }
 
-            var typesCache = TypeCache.GetTypesDerivedFrom(parentType);
-            var typesList = typesCache.ToList();
-            typesList.Add(parentType);
-            for (var i = typesList.Count - 1; i >= 0; i--)
-            {
-                var type = typesList[i];
-                if (constraint.IsSatisfied(type))
-                {
-                    continue;
-                }
-
-                typesList.RemoveAt(i);
-            }
-
+            var typesList = FindTypes(constraint);
             return cachedCollections[key] = new TypesCachedCollection(typesList);
         }
 
@@ -90,5 +78,51 @@ public static bool TryGetTypeFromManagedReferenceFullTypeName(string managedRefe
 
             return false;
         }
+
+        public static List<Type> FindTypes(TypeConstraintContext constraint)
+        {
+#if UNITY_2019_2_OR_NEWER
+            var parentType = constraint.TargetType;
+            var typesCache = TypeCache.GetTypesDerivedFrom(parentType);
+            var typesList = typesCache.ToList();
+            typesList.Add(parentType);
+            for (var i = typesList.Count - 1; i >= 0; i--)
+            {
+                var type = typesList[i];
+                if (constraint.IsSatisfied(type))
+                {
+                    continue;
+                }
+
+                typesList.RemoveAt(i);
+            }
+#else
+            var typesList = new List<Type>();
+            var assemblies = AppDomain.CurrentDomain.GetAssemblies();
+            foreach (var assembly in assemblies)
+            {
+                typesList.AddRange(FindTypes(constraint, assembly));
+            }
+
+            typesList.Sort((a, b) => a.FullName.CompareTo(b.FullName));
+#endif
+            return typesList;
+        }
+
+        public static List<Type> FindTypes(TypeConstraintContext constraint, Assembly assembly)
+        {
+            var types = new List<Type>();
+            foreach (var type in assembly.GetTypes())
+            {
+                if (!constraint.IsSatisfied(type))
+                {
+                    continue;
+                }
+
+                types.Add(type);
+            }
+
+            return types;
+        }
     }
 }

Assets/Editor Toolbox/Tests/Editor/TypesFilteringTest.cs

@@ -115,7 +115,7 @@ public void TestStandardConstraintPass5()
         [Test]
         public void TestStandardConstraintPass6()
         {
-            var constraint = new TypeConstraintStandard(typeof(ClassBase), TypeSettings.Class | TypeSettings.Interface, true, false);
+            var constraint = new TypeConstraintStandard(typeof(ClassBase), TypeSettings.Class | TypeSettings.Interface, false, false);
             var collection = TypeUtilities.GetCollection(constraint);
             Assert.IsFalse(collection.Contains(typeof(ClassBase)));
             Assert.IsTrue(collection.Contains(typeof(ClassWithInterface1)));

Assets/Examples/Scripts/SampleBehaviour6.cs

@@ -6,10 +6,12 @@
 [AddComponentMenu("Editor Toolbox/Cheat Sheet 6 (Serialize Reference)")]
 public class SampleBehaviour6 : MonoBehaviour
 {
+#if UNITY_2019_3_OR_NEWER
     [SerializeReference, ReferencePicker]
     public Interface1 var1;
     [SerializeReference, ReferencePicker]
     public ClassWithInterfaceBase var2;
+#endif
 
     public interface Interface1 { }