FIX: Fixed custom processor display in input action asset UI after entering/exiting play mode (#1671)

* Fixed custom processor display in input asset action UI

AddTypeRegistration now supports being called twice with same details, and avoids adding an alias to itself. in editor.

It also warns if called twice with same named entry with a different type

A new test is added which failed before this change and passes after
Actions_AddingSameProcessorTwice_DoesntImpactUIHideState

Another test added to check same named processor overrides the original of same name
Actions_AddingSameNamedProcessorWithDifferentResult_OverridesOriginal

* Updated change log

* Fixed tests to run on stand alone player

And updated formatting

Author: lyndon-unity

Assets/Tests/InputSystem/CoreTests_Actions.cs

@@ -4310,7 +4310,6 @@ public void Actions_CanAddInteractionsToActions()
     {
         var gamepad = InputSystem.AddDevice<Gamepad>();
 
-        InputSystem.RegisterProcessor<ConstantVector2TestProcessor>();
         var action = new InputAction(interactions: "Tap(duration=0.123)");
         action.AddBinding("<Gamepad>/buttonSouth");
         action.Enable();
@@ -4490,6 +4489,68 @@ public void Actions_CanAddScaleProcessor()
         Assert.That(receivedValues, Has.Exactly(1).EqualTo(0.5f * 2));
     }
 
+    private class ConstantFloat1TestProcessor : InputProcessor<float>
+    {
+        public override float Process(float value, InputControl control)
+        {
+            return 1.0f;
+        }
+    }
+    private class ConstantFloat2TestProcessor : InputProcessor<float>
+    {
+        public override float Process(float value, InputControl control)
+        {
+            return 2.0f;
+        }
+    }
+
+#if UNITY_EDITOR
+    [Test]
+    [Category("Actions")]
+    public void Actions_AddingSameProcessorTwice_DoesntImpactUIHideState()
+    {
+        InputSystem.RegisterProcessor<ConstantFloat1TestProcessor>();
+        Assert.That(InputSystem.TryGetProcessor("ConstantFloat1Test"), Is.Not.EqualTo(null));
+
+        bool hide = InputSystem.s_Manager.processors.ShouldHideInUI("ConstantFloat1Test");
+        Assert.That(hide, Is.EqualTo(false));
+
+        InputSystem.RegisterProcessor<ConstantFloat1TestProcessor>();
+        // Check we haven't caused this to alias with itself and cause it to be hidden in the UI
+        hide = InputSystem.s_Manager.processors.ShouldHideInUI("ConstantFloat1Test");
+        Assert.That(hide, Is.EqualTo(false));
+    }
+
+#endif
+
+    [Test]
+    [Category("Actions")]
+    public void Actions_AddingSameNamedProcessorWithDifferentResult_OverridesOriginal()
+    {
+        var gamepad = InputSystem.AddDevice<Gamepad>();
+
+        InputSystem.RegisterProcessor<ConstantFloat1TestProcessor>("ConstantFloatTest");
+        InputSystem.RegisterProcessor<ConstantFloat2TestProcessor>("ConstantFloatTest");
+
+        var action = new InputAction(processors: "ConstantFloatTest");
+        action.AddBinding("<Gamepad>/leftTrigger");
+        action.Enable();
+
+        float? receivedValue = null;
+        action.performed +=
+            ctx =>
+        {
+            Assert.That(receivedValue, Is.Null);
+            receivedValue = ctx.ReadValue<float>();
+        };
+
+        InputSystem.QueueStateEvent(gamepad, new GamepadState { leftTrigger = 0.5f });
+        InputSystem.Update();
+
+        Assert.That(receivedValue, Is.Not.Null);
+        Assert.That(receivedValue.Value, Is.EqualTo(2.0).Within(0.00001));
+    }
+
     [Test]
     [Category("Actions")]
     public void Actions_ControlsUpdateWhenNewDeviceIsAdded()

Packages/com.unity.inputsystem/CHANGELOG.md

@@ -20,6 +20,7 @@ however, it has to be formatted properly to pass verification tests.
 
 ### Fixed
 - Fixed BindingPath String-Comparison to be culture and case insensitive (case ISXB-449).
+- Fixed custom processor display in the input action asset UI after entering/exiting play mode (previously they got hidden) ([case ISXB-445](https://issuetracker.unity3d.com/product/unity/issues/guid/ISXB-445)).
 
 ## [1.5.1] - 2023-03-15
 

Packages/com.unity.inputsystem/InputSystem/Utilities/TypeTable.cs

@@ -53,8 +53,20 @@ public void AddTypeRegistration(string name, Type type)
             var internedName = new InternedString(name);
 
             #if UNITY_EDITOR
-            if (table.ContainsValue(type))
-                aliases.Add(internedName);
+            // First check if the name has already been added to the table
+            // This allows safely calling this function multiple times with same name
+            // and prevents adding an alias to itself
+            Type originalType;
+            if (table.TryGetValue(internedName, out originalType))
+            {
+                // We don't warn about overriding any existing name/type mapping as that was previously supported
+                table.Remove(internedName);
+            }
+            else
+            {
+                if (table.ContainsValue(type))
+                    aliases.Add(internedName);
+            }
             #endif
 
             table[internedName] = type;