Query: SqlServer: Add translation for string.IndexOf(string, int)

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

@@ -37,7 +37,7 @@ public CosmosMethodCallTranslatorProvider(
  new IMethodCallTranslator[]
  {
  new EqualsTranslator(sqlExpressionFactory),
- new StringMethodTranslator(sqlExpressionFactory),
+ new CosmosStringMethodTranslator(sqlExpressionFactory),
  new ContainsTranslator(sqlExpressionFactory),
  new RandomTranslator(sqlExpressionFactory),
  new MathTranslator(sqlExpressionFactory)

src/EFCore.Cosmos/Query/Internal/StringMethodTranslator.cs → src/EFCore.Cosmos/Query/Internal/CosmosStringMethodTranslator.cs

@@ -15,7 +15,7 @@ namespace Microsoft.EntityFrameworkCore.Cosmos.Query.Internal
  /// any release. You should only use it directly in your code with extreme caution and knowing that
  /// doing so can result in application failures when updating to a new Entity Framework Core release.
  /// </summary>
- public class StringMethodTranslator : IMethodCallTranslator
+ public class CosmosStringMethodTranslator : IMethodCallTranslator
  {
  private static readonly MethodInfo _indexOfMethodInfo
  = typeof(string).GetRequiredRuntimeMethod(nameof(string.IndexOf), typeof(string));
@@ -98,7 +98,7 @@ private static readonly MethodInfo _stringComparisonWithComparisonTypeArgumentSt
  /// any release. You should only use it directly in your code with extreme caution and knowing that
  /// doing so can result in application failures when updating to a new Entity Framework Core release.
  /// </summary>
- public StringMethodTranslator(ISqlExpressionFactory sqlExpressionFactory)
+ public CosmosStringMethodTranslator(ISqlExpressionFactory sqlExpressionFactory)
  {
  _sqlExpressionFactory = sqlExpressionFactory;
  }

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

@@ -23,6 +23,9 @@ public class SqlServerStringMethodTranslator : IMethodCallTranslator
  private static readonly MethodInfo _indexOfMethodInfo
  = typeof(string).GetRequiredRuntimeMethod(nameof(string.IndexOf), typeof(string));
 
+ private static readonly MethodInfo _indexOfMethodInfoWithStartingPosition
+ = typeof(string).GetRequiredRuntimeMethod(nameof(string.IndexOf), new[] { typeof(string), typeof(int) });
+
  private static readonly MethodInfo _replaceMethodInfo
  = typeof(string).GetRequiredRuntimeMethod(nameof(string.Replace), typeof(string), typeof(string));
 
@@ -115,46 +118,12 @@ public SqlServerStringMethodTranslator(ISqlExpressionFactory sqlExpressionFactor
  {
  if (_indexOfMethodInfo.Equals(method))
  {
- var argument = arguments[0];
- var stringTypeMapping = ExpressionExtensions.InferTypeMapping(instance, argument)!;
- argument = _sqlExpressionFactory.ApplyTypeMapping(argument, stringTypeMapping);
-
- SqlExpression charIndexExpression;
- var storeType = stringTypeMapping.StoreType;
- if (string.Equals(storeType, "nvarchar(max)", StringComparison.OrdinalIgnoreCase)
- || string.Equals(storeType, "varchar(max)", StringComparison.OrdinalIgnoreCase))
- {
- charIndexExpression = _sqlExpressionFactory.Function(
- "CHARINDEX",
- new[] { argument, _sqlExpressionFactory.ApplyTypeMapping(instance, stringTypeMapping) },
- nullable: true,
- argumentsPropagateNullability: new[] { true, true },
- typeof(long));
-
- charIndexExpression = _sqlExpressionFactory.Convert(charIndexExpression, typeof(int));
- }
- else
- {
- charIndexExpression = _sqlExpressionFactory.Function(
- "CHARINDEX",
- new[] { argument, _sqlExpressionFactory.ApplyTypeMapping(instance, stringTypeMapping) },
- nullable: true,
- argumentsPropagateNullability: new[] { true, true },
- method.ReturnType);
- }
-
- charIndexExpression = _sqlExpressionFactory.Subtract(charIndexExpression, _sqlExpressionFactory.Constant(1));
+ return TranslateIndexOf(instance, method, arguments[0], null);
+ }
 
- return _sqlExpressionFactory.Case(
- new[]
- {
- new CaseWhenClause(
- _sqlExpressionFactory.Equal(
- argument,
- _sqlExpressionFactory.Constant(string.Empty, stringTypeMapping)),
- _sqlExpressionFactory.Constant(0))
- },
- charIndexExpression);
+ if (_indexOfMethodInfoWithStartingPosition.Equals(method))
+ {
+ return TranslateIndexOf(instance, method, arguments[0], arguments[1]);
  }
 
  if (_replaceMethodInfo.Equals(method))
@@ -465,6 +434,60 @@ private SqlExpression TranslateStartsEndsWith(SqlExpression instance, SqlExpress
  pattern);
  }
 
+ private SqlExpression TranslateIndexOf(SqlExpression instance, MethodInfo method, SqlExpression searchExpression, SqlExpression? startIndex)
+ {
+ var stringTypeMapping = ExpressionExtensions.InferTypeMapping(instance, searchExpression)!;
+ searchExpression = _sqlExpressionFactory.ApplyTypeMapping(searchExpression, stringTypeMapping);
+ instance = _sqlExpressionFactory.ApplyTypeMapping(instance, stringTypeMapping);
+
+ var charIndexArguments = new List<SqlExpression> { searchExpression, instance };
+
+ if (startIndex is not null)
+ {
+ charIndexArguments.Add(_sqlExpressionFactory.Add(startIndex, _sqlExpressionFactory.Constant(1)));
+ }
+
+ var argumentsPropagateNullability = Enumerable.Repeat(true, charIndexArguments.Count);
+
+ SqlExpression charIndexExpression;
+ var storeType = stringTypeMapping.StoreType;
+ if (string.Equals(storeType, "nvarchar(max)", StringComparison.OrdinalIgnoreCase)
+ || string.Equals(storeType, "varchar(max)", StringComparison.OrdinalIgnoreCase))
+ {
+ charIndexExpression = _sqlExpressionFactory.Function(
+ "CHARINDEX",
+ charIndexArguments,
+ nullable: true,
+ argumentsPropagateNullability,
+ typeof(long));
+
+ charIndexExpression = _sqlExpressionFactory.Convert(charIndexExpression, typeof(int));
+ }
+ else
+ {
+ charIndexExpression = _sqlExpressionFactory.Function(
+ "CHARINDEX",
+ charIndexArguments,
+ nullable: true,
+ argumentsPropagateNullability,
+ method.ReturnType);
+ }
+
+ charIndexExpression = _sqlExpressionFactory.Subtract(charIndexExpression, _sqlExpressionFactory.Constant(1));
+
+ return _sqlExpressionFactory.Case(
+ new[]
+ {
+ new CaseWhenClause(
+ _sqlExpressionFactory.Equal(
+ searchExpression,
+ _sqlExpressionFactory.Constant(string.Empty, stringTypeMapping)),
+ _sqlExpressionFactory.Constant(0))
+ },
+ charIndexExpression);
+ }
+
+
  // See https://docs.microsoft.com/en-us/sql/t-sql/language-elements/like-transact-sql
  private bool IsLikeWildChar(char c)
  => c == '%' || c == '_' || c == '[';

test/EFCore.Specification.Tests/Query/NorthwindFunctionsQueryTestBase.cs

@@ -1561,6 +1561,15 @@ public virtual Task Indexof_with_emptystring(bool async)
  ss => ss.Set<Customer>().Where(c => c.CustomerID == "ALFKI").Select(c => c.ContactName.IndexOf(string.Empty)));
  }
 
+ [ConditionalTheory]
+ [MemberData(nameof(IsAsyncData))]
+ public virtual Task Indexof_with_one_arg(bool async)
+ {
+ return AssertQueryScalar(
+ async,
+ ss => ss.Set<Customer>().Where(c => c.CustomerID == "ALFKI").Select(c => c.ContactName.IndexOf("a")));
+ }
+
  [ConditionalTheory]
  [MemberData(nameof(IsAsyncData))]
  public virtual Task Indexof_with_starting_position(bool async)

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

@@ -1528,13 +1528,28 @@ FROM [Customers] AS [c]
 WHERE [c].[CustomerID] = N'ALFKI'");
  }
 
- [ConditionalTheory(Skip = "issue #25396")]
+ public override async Task Indexof_with_one_arg(bool async)
+ {
+ await base.Indexof_with_one_arg(async);
+
+ AssertSql(
+ @"SELECT CASE
+ WHEN N'a' = N'' THEN 0
+ ELSE CAST(CHARINDEX(N'a', [c].[ContactName]) AS int) - 1
+END
+FROM [Customers] AS [c]
+WHERE [c].[CustomerID] = N'ALFKI'");
+ }
+
  public override async Task Indexof_with_starting_position(bool async)
  {
  await base.Indexof_with_starting_position(async);
 
  AssertSql(
- @"SELECT [c].[ContactName]
+ @"SELECT CASE
+ WHEN N'a' = N'' THEN 0
+ ELSE CAST(CHARINDEX(N'a', [c].[ContactName], 3 + 1) AS int) - 1
+END
 FROM [Customers] AS [c]
 WHERE [c].[CustomerID] = N'ALFKI'");
  }