From 04b93af4ae333013e4fe00013a196268d314cb00 Mon Sep 17 00:00:00 2001
From: Steve Lee <slee@microsoft.com>
Date: Mon, 3 Apr 2023 09:36:36 -0700
Subject: [PATCH] Enable type conversion of `AutomationNull` to `$null` for
 assignment (#19415)

---
 .../engine/LanguagePrimitives.cs                     |  6 ++++++
 .../Language/Scripting/Scripting.Followup.Tests.ps1  | 12 ++++++++++++
 2 files changed, 18 insertions(+)

diff --git a/src/System.Management.Automation/engine/LanguagePrimitives.cs b/src/System.Management.Automation/engine/LanguagePrimitives.cs
index b1c7cab0ac..ac3c1c1a70 100644
--- a/src/System.Management.Automation/engine/LanguagePrimitives.cs
+++ b/src/System.Management.Automation/engine/LanguagePrimitives.cs
@@ -4691,6 +4691,12 @@ namespace System.Management.Automation
                                     }
                                 }
 
+                                // treat AutomationNull.Value as null for consistency
+                                if (propValue == AutomationNull.Value)
+                                {
+                                    propValue = null;
+                                }
+
                                 property.Value = propValue;
                             }
                             else
diff --git a/test/powershell/Language/Scripting/Scripting.Followup.Tests.ps1 b/test/powershell/Language/Scripting/Scripting.Followup.Tests.ps1
index 888c43b357..fff4993ffe 100644
--- a/test/powershell/Language/Scripting/Scripting.Followup.Tests.ps1
+++ b/test/powershell/Language/Scripting/Scripting.Followup.Tests.ps1
@@ -30,6 +30,18 @@ Describe "Scripting.Followup.Tests" -Tags "CI" {
         $arraylist.Count | Should -Be 0
     }
 
+    It 'AutomationNull should be same as null for type conversion' {
+        $result = pwsh -noprofile -command {
+            class Example {
+                [string[]]$LogMessage
+            }
+
+            [Example] @{ LogMessage = [System.Management.Automation.Internal.AutomationNull]::Value }
+        }
+
+        $result.LogMessage | Should -BeNullOrEmpty
+    }
+
     ## fix https://github.com/PowerShell/PowerShell/issues/17165
     It "([bool] `$var = 42) should return the varaible value" {
         ([bool]$var = 42).GetType().FullName | Should -Be "System.Boolean"