[automated] Merge branch 'release/10.0' => 'main'

src/EFCore/Query/Internal/ExpressionTreeFuncletizer.cs

@@ -2101,7 +2101,7 @@ bool PreserveConvertNode(Expression expression)
             // In many databases, parameter names must start with a letter or underscore.
             // The same is true for C# variable names, from which we derive the parameter name, so in principle we shouldn't see an issue;
             // but just in case, prepend an underscore if the parameter name doesn't start with a letter or underscore.
-            if (!char.IsLetter(parameterName[0]) && parameterName[0] != '_')
+            if (parameterName.Length > 0 && !char.IsLetter(parameterName[0]) && parameterName[0] != '_')
             {
                 parameterName = "_" + parameterName;
             }
@@ -2215,7 +2215,7 @@ static string SanitizeCompilerGeneratedName(string s)
         {
             // Compiler-generated field names intentionally contain illegal characters, specifically angle brackets <>.
             // In cases where there's something within the angle brackets, that tends to be the original user-provided variable name
-            // (e.g. <PropertyName>k__BackingField). If we see angle brackets, extract that out, or it the angle brackets contain no
+            // (e.g. <PropertyName>k__BackingField). If we see angle brackets, extract that out, or if the angle brackets contain no
             // content, strip them out entirely and take what comes after.
             var closingBracket = s.IndexOf('>');
             if (closingBracket == -1)

src/EFCore/Query/Internal/NavigationExpandingExpressionVisitor.cs

@@ -58,6 +58,7 @@ private static readonly PropertyInfo QueryContextContextPropertyInfo
 
     private readonly Dictionary<string, object?> _parameters = new();
 
+
     /// <summary>
     ///     This is an internal API that supports the Entity Framework Core infrastructure and not subject to
     ///     the same compatibility standards as public APIs. It may be changed or removed without notice in
@@ -1082,11 +1083,18 @@ private Expression ProcessExecuteUpdate(NavigationExpansionExpression source, Me
 
         // Apply any pending selector before processing the ExecuteUpdate setters; this adds a Select() (if necessary) before
         // ExecuteUpdate, to avoid the pending selector flowing into each setter lambda and making it more complicated.
+        // However, only do this when the pending selector produces entity/structural type references (i.e. the snapshot is not just
+        // a DefaultExpression). When the pending selector projects only scalar values (e.g. select new { p.Used, n.Qty }),
+        // applying it would lose the connection between the projected scalar and the original entity property, breaking
+        // ExecuteUpdate's property selector recognition (#37771).
         var newStructure = SnapshotExpression(source.PendingSelector);
-        var queryable = Reduce(source);
-        var navigationTree = new NavigationTreeExpression(newStructure);
-        var parameterName = source.CurrentParameter.Name ?? GetParameterName("e");
-        source = new NavigationExpansionExpression(queryable, navigationTree, navigationTree, parameterName);
+        if (newStructure is not DefaultExpression)
+        {
+            var queryable = Reduce(source);
+            var navigationTree = new NavigationTreeExpression(newStructure);
+            var parameterName = source.CurrentParameter.Name ?? GetParameterName("e");
+            source = new NavigationExpansionExpression(queryable, navigationTree, navigationTree, parameterName);
+        }
 
         NewArrayExpression settersArray;
         switch (setters)

test/EFCore.Relational.Specification.Tests/BulkUpdates/NorthwindBulkUpdatesRelationalTestBase.cs

@@ -99,6 +99,44 @@ FROM [Customers]
                 }
             });
 
+    [ConditionalTheory, MemberData(nameof(IsAsyncData))] // #37771
+    public virtual Task Update_with_select_mixed_entity_scalar_anonymous_projection(bool async)
+        => TestHelpers.ExecuteWithStrategyInTransactionAsync(
+            () => Fixture.CreateContext(),
+            (facade, transaction) => Fixture.UseTransaction(facade, transaction),
+            async context =>
+            {
+                var queryable = context.Set<Customer>().Select(c => new { Entity = c, c.ContactName });
+
+                if (async)
+                {
+                    await queryable.ExecuteUpdateAsync(s => s.SetProperty(c => c.Entity.ContactName, "Updated"));
+                }
+                else
+                {
+                    queryable.ExecuteUpdate(s => s.SetProperty(c => c.Entity.ContactName, "Updated"));
+                }
+            });
+
+    [ConditionalTheory, MemberData(nameof(IsAsyncData))] // #37771
+    public virtual Task Update_with_select_scalar_anonymous_projection(bool async)
+        => TestHelpers.ExecuteWithStrategyInTransactionAsync(
+            () => Fixture.CreateContext(),
+            (facade, transaction) => Fixture.UseTransaction(facade, transaction),
+            async context =>
+            {
+                var queryable = context.Set<Customer>().Select(c => new { c.ContactName, c.City });
+
+                if (async)
+                {
+                    await queryable.ExecuteUpdateAsync(s => s.SetProperty(c => c.ContactName, "Updated"));
+                }
+                else
+                {
+                    queryable.ExecuteUpdate(s => s.SetProperty(c => c.ContactName, "Updated"));
+                }
+            });
+
     protected static async Task AssertTranslationFailed(string details, Func<Task> query)
     {
         var exception = await Assert.ThrowsAsync<InvalidOperationException>(query);

test/EFCore.SqlServer.FunctionalTests/BulkUpdates/NorthwindBulkUpdatesSqlServerTest.cs

@@ -1665,6 +1665,34 @@ OFFSET @p ROWS
 """);
     }
 
+    public override async Task Update_with_select_mixed_entity_scalar_anonymous_projection(bool async)
+    {
+        await base.Update_with_select_mixed_entity_scalar_anonymous_projection(async);
+
+        AssertSql(
+            """
+@p='Updated' (Size = 30)
+
+UPDATE [c]
+SET [c].[ContactName] = @p
+FROM [Customers] AS [c]
+""");
+    }
+
+    public override async Task Update_with_select_scalar_anonymous_projection(bool async)
+    {
+        await base.Update_with_select_scalar_anonymous_projection(async);
+
+        AssertSql(
+            """
+@p='Updated' (Size = 30)
+
+UPDATE [c]
+SET [c].[ContactName] = @p
+FROM [Customers] AS [c]
+""");
+    }
+
     private void AssertSql(params string[] expected)
         => Fixture.TestSqlLoggerFactory.AssertBaseline(expected);
 

test/EFCore.Sqlite.FunctionalTests/BulkUpdates/NorthwindBulkUpdatesSqliteTest.cs

@@ -1571,6 +1571,32 @@ ORDER BY "o"."OrderID"
 """);
     }
 
+    public override async Task Update_with_select_mixed_entity_scalar_anonymous_projection(bool async)
+    {
+        await base.Update_with_select_mixed_entity_scalar_anonymous_projection(async);
+
+        AssertSql(
+            """
+@p='Updated' (Size = 7)
+
+UPDATE "Customers" AS "c"
+SET "ContactName" = @p
+""");
+    }
+
+    public override async Task Update_with_select_scalar_anonymous_projection(bool async)
+    {
+        await base.Update_with_select_scalar_anonymous_projection(async);
+
+        AssertSql(
+            """
+@p='Updated' (Size = 7)
+
+UPDATE "Customers" AS "c"
+SET "ContactName" = @p
+""");
+    }
+
     private void AssertSql(params string[] expected)
         => Fixture.TestSqlLoggerFactory.AssertBaseline(expected);