From 4f7c38c77b2cf019af703ea657b3bb97e0bbaf89 Mon Sep 17 00:00:00 2001
From: Arthur Vickers <ajcvickers@hotmail.com>
Date: Fri, 17 Dec 2021 10:52:26 +0000
Subject: [PATCH] Updated to return constant hash codes.

---
 .../Query/SqlExpressions/SelectExpression.Helper.cs  | 11 +----------
 .../Query/SqlExpressions/TableExpressionBase.cs      | 12 +-----------
 2 files changed, 2 insertions(+), 21 deletions(-)

diff --git a/src/EFCore.Relational/Query/SqlExpressions/SelectExpression.Helper.cs b/src/EFCore.Relational/Query/SqlExpressions/SelectExpression.Helper.cs
index da76365e0dd..3d23e2430dc 100644
--- a/src/EFCore.Relational/Query/SqlExpressions/SelectExpression.Helper.cs
+++ b/src/EFCore.Relational/Query/SqlExpressions/SelectExpression.Helper.cs
@@ -340,7 +340,6 @@ public AliasUniquifier(HashSet<string> usedAliases)
 
     private sealed class TableReferenceExpression : Expression
     {
-        private int? _hashCode;
         private SelectExpression _selectExpression;
 
         public TableReferenceExpression(SelectExpression selectExpression, string alias)
@@ -393,15 +392,7 @@ private bool Equals(TableReferenceExpression tableReferenceExpression)
 
         /// <inheritdoc />
         public override int GetHashCode()
-        {
-            // ReSharper disable NonReadonlyMemberInGetHashCode
-            // Ensure hashcode does not change after it has been created for this object.
-            Check.DebugAssert(
-                _hashCode == null || _hashCode == HashCode.Combine(Alias),
-                "Hashed value has mutated.");
-
-            return _hashCode ??= HashCode.Combine(Alias);
-        }
+            => 0;
     }
 
     private sealed class ConcreteColumnExpression : ColumnExpression
diff --git a/src/EFCore.Relational/Query/SqlExpressions/TableExpressionBase.cs b/src/EFCore.Relational/Query/SqlExpressions/TableExpressionBase.cs
index ac772b95859..768ceacd41b 100644
--- a/src/EFCore.Relational/Query/SqlExpressions/TableExpressionBase.cs
+++ b/src/EFCore.Relational/Query/SqlExpressions/TableExpressionBase.cs
@@ -14,8 +14,6 @@ namespace Microsoft.EntityFrameworkCore.Query.SqlExpressions;
 /// </summary>
 public abstract class TableExpressionBase : Expression, IPrintableExpression
 {
-    private int? _hashCode;
-
     /// <summary>
     ///     Creates a new instance of the <see cref="TableExpressionBase" /> class.
     /// </summary>
@@ -64,13 +62,5 @@ private bool Equals(TableExpressionBase tableExpressionBase)
 
     /// <inheritdoc />
     public override int GetHashCode()
-    {
-        // ReSharper disable NonReadonlyMemberInGetHashCode
-        // Ensure hashcode does not change after it has been created for this object.
-        Check.DebugAssert(
-            _hashCode == null || _hashCode == HashCode.Combine(Alias),
-            "Hashed value has mutated.");
-
-        return _hashCode ??= HashCode.Combine(Alias);
-    }
+        => 0;
 }