From 77054ff586d2c723114862347b798bd89f8e0c56 Mon Sep 17 00:00:00 2001
From: MartinGC94 <42123497+MartinGC94@users.noreply.github.com>
Date: Wed, 16 Jun 2021 01:56:14 +0200
Subject: [PATCH] Fix splatting being treated as positional parameter (#14623)

---
 .../engine/CommandCompletion/PseudoParameterBinder.cs      | 7 +++++++
 test/powershell/Host/TabCompletion/TabCompletion.Tests.ps1 | 7 +++++++
 2 files changed, 14 insertions(+)

diff --git a/src/System.Management.Automation/engine/CommandCompletion/PseudoParameterBinder.cs b/src/System.Management.Automation/engine/CommandCompletion/PseudoParameterBinder.cs
index 0d19528023..c98be4ccac 100644
--- a/src/System.Management.Automation/engine/CommandCompletion/PseudoParameterBinder.cs
+++ b/src/System.Management.Automation/engine/CommandCompletion/PseudoParameterBinder.cs
@@ -1862,6 +1862,13 @@ namespace System.Management.Automation.Language
             while (unboundArgumentsIndex < unboundArgumentsCollection.Count)
             {
                 AstParameterArgumentPair argument = unboundArgumentsCollection[unboundArgumentsIndex++];
+                if (argument is AstPair astPair
+                    && astPair.Argument is VariableExpressionAst argumentVariable
+                    && argumentVariable.Splatted)
+                {
+                    continue;
+                }
+
                 if (!argument.ParameterSpecified)
                 {
                     result = argument;
diff --git a/test/powershell/Host/TabCompletion/TabCompletion.Tests.ps1 b/test/powershell/Host/TabCompletion/TabCompletion.Tests.ps1
index 01f58f06bf..356101256b 100644
--- a/test/powershell/Host/TabCompletion/TabCompletion.Tests.ps1
+++ b/test/powershell/Host/TabCompletion/TabCompletion.Tests.ps1
@@ -1022,6 +1022,13 @@ dir -Recurse `
             $res.CompletionMatches | Should -HaveCount 4
             [string]::Join(',', ($res.CompletionMatches.completiontext | Sort-Object)) | Should -BeExactly "-wa,-Wait,-WarningAction,-WarningVariable"
         }
+
+        It "Test completion with splatted variable" {
+            $inputStr = 'Get-Content @Splat -P'
+            $res = TabExpansion2 -inputScript $inputStr -cursorColumn $inputStr.Length
+            $res.CompletionMatches | Should -HaveCount 4
+            [string]::Join(',', ($res.CompletionMatches.completiontext | Sort-Object)) | Should -BeExactly "-Path,-PipelineVariable,-PSPath,-pv"
+        }
     }
 
     Context "Module completion for 'using module'" {