Fix string.Length translation after SqlQuery

src/EFCore.Cosmos/Query/Internal/CosmosStringMemberTranslator.cs

@@ -37,11 +37,11 @@ public CosmosStringMemberTranslator(ISqlExpressionFactory sqlExpressionFactory)
         IDiagnosticsLogger<DbLoggerCategory.Query> logger)
     {
         if (member.Name == nameof(string.Length)
-            && instance?.Type == typeof(string))
+            && member.DeclaringType == typeof(string))
         {
             return _sqlExpressionFactory.Function(
                 "LENGTH",
-                new[] { instance },
+                new[] { instance! },
                 returnType);
         }
 

src/EFCore.SqlServer/Query/Internal/SqlServerStringMemberTranslator.cs

@@ -39,12 +39,12 @@ public SqlServerStringMemberTranslator(ISqlExpressionFactory sqlExpressionFactor
         IDiagnosticsLogger<DbLoggerCategory.Query> logger)
     {
         if (member.Name == nameof(string.Length)
-            && instance?.Type == typeof(string))
+            && member.DeclaringType == typeof(string))
         {
             return _sqlExpressionFactory.Convert(
                 _sqlExpressionFactory.Function(
                     "LEN",
-                    new[] { instance },
+                    new[] { instance! },
                     nullable: true,
                     argumentsPropagateNullability: new[] { true },
                     typeof(long)),

src/EFCore.Sqlite.Core/Query/Internal/SqliteStringLengthTranslator.cs

@@ -37,11 +37,11 @@ public SqliteStringLengthTranslator(ISqlExpressionFactory sqlExpressionFactory)
         MemberInfo member,
         Type returnType,
         IDiagnosticsLogger<DbLoggerCategory.Query> logger)
-        => instance?.Type == typeof(string)
+        => member.DeclaringType == typeof(string)
             && member.Name == nameof(string.Length)
                 ? _sqlExpressionFactory.Function(
                     "length",
-                    new[] { instance },
+                    new[] { instance! },
                     nullable: true,
                     argumentsPropagateNullability: new[] { true },
                     returnType)

test/EFCore.Relational.Specification.Tests/Query/SqlQueryTestBase.cs

@@ -1221,6 +1221,42 @@ public virtual void Ad_hoc_type_with_unmapped_property_throws()
                 () => context.Database.SqlQueryRaw<Person>(NormalizeDelimitersInRawString(@"SELECT * FROM [People]"))).Message);
     }
 
+    [ConditionalTheory]
+    [MemberData(nameof(IsAsyncData))]
+    public virtual async Task SqlQueryRaw_then_String_Length(bool async)
+    {
+        using var context = CreateContext();
+        var rawQuery = NormalizeDelimitersInRawString("SELECT 'x' AS [Value] FROM [Customers]");
+        var query = context.Database.SqlQueryRaw<string>(rawQuery).Where(s => s.Length == 0);
+
+        if (async)
+        {
+            await query.LoadAsync();
+        }
+        else
+        {
+            query.Load();
+        }
+    }
+
+    [ConditionalTheory]
+    [MemberData(nameof(IsAsyncData))]
+    public virtual async Task SqlQueryRaw_then_String_ToUpper_String_Length(bool async)
+    {
+        using var context = CreateContext();
+        var rawQuery = NormalizeDelimitersInRawString("SELECT 'x' AS [Value] FROM [Customers]");
+        var query = context.Database.SqlQueryRaw<string>(rawQuery).Where(s => s.ToUpper().Length == 0);
+
+        if (async)
+        {
+            await query.LoadAsync();
+        }
+        else
+        {
+            query.Load();
+        }
+    }
+
     protected class Blog
     {
         public int Id { get; set; }

test/EFCore.SqlServer.FunctionalTests/Query/SqlQuerySqlServerTest.cs

@@ -785,6 +785,34 @@ public override async Task SqlQueryRaw_composed_with_common_table_expression(boo
         Assert.Equal(RelationalStrings.FromSqlNonComposable, exception.Message);
     }
 
+    public override async Task SqlQueryRaw_then_String_Length(bool async)
+    {
+        await base.SqlQueryRaw_then_String_Length(async);
+
+        AssertSql(
+            """
+SELECT [s].[Value]
+FROM (
+    SELECT 'x' AS "Value" FROM "Customers"
+) AS [s]
+WHERE CAST(LEN([s].[Value]) AS int) = 0
+""");
+    }
+
+    public override async Task SqlQueryRaw_then_String_ToUpper_String_Length(bool async)
+    {
+        await base.SqlQueryRaw_then_String_ToUpper_String_Length(async);
+
+        AssertSql(
+            """
+SELECT [s].[Value]
+FROM (
+    SELECT 'x' AS "Value" FROM "Customers"
+) AS [s]
+WHERE CAST(LEN(UPPER([s].[Value])) AS int) = 0
+""");
+    }
+
     protected override DbParameter CreateDbParameter(string name, object value)
         => new SqlParameter { ParameterName = name, Value = value };
 

test/EFCore.Sqlite.FunctionalTests/Query/SqlQuerySqliteTest.cs

@@ -79,6 +79,34 @@ WHERE instr("m"."ContactName", 'z') > 0
 """);
     }
 
+    public override async Task SqlQueryRaw_then_String_Length(bool async)
+    {
+        await base.SqlQueryRaw_then_String_Length(async);
+
+        AssertSql(
+            """
+SELECT "s"."Value"
+FROM (
+    SELECT 'x' AS "Value" FROM "Customers"
+) AS "s"
+WHERE length("s"."Value") = 0
+""");
+    }
+
+    public override async Task SqlQueryRaw_then_String_ToUpper_String_Length(bool async)
+    {
+        await base.SqlQueryRaw_then_String_ToUpper_String_Length(async);
+
+        AssertSql(
+            """
+SELECT "s"."Value"
+FROM (
+    SELECT 'x' AS "Value" FROM "Customers"
+) AS "s"
+WHERE length(upper("s"."Value")) = 0
+""");
+    }
+
     protected override DbParameter CreateDbParameter(string name, object value)
         => new SqliteParameter { ParameterName = name, Value = value };