Ef Core 5 Preview: OrderBy(x => x.IndexOf(searchTerm)) error

[alienwareone]

https://github.com/alienwareone/EfCoreOrderByIndexOfBug

This was working in v3.1.x

var searchTerm = "Na";
var names = applicationDbContext.Categories
    .Select(x => x.Name)
    .Distinct()
    .OrderBy(x => x.IndexOf(searchTerm))
    .ThenBy(x => x)
    .Take(10)
    .ToList();

Value cannot be null. (Parameter 'operand')

   at Microsoft.EntityFrameworkCore.Utilities.Check.NotNull[T](T value, String parameterName)
   at Microsoft.EntityFrameworkCore.Query.SqlExpressions.CaseExpression..ctor(SqlExpression operand, IReadOnlyList`1 whenClauses, SqlExpression elseResult)
   at Microsoft.EntityFrameworkCore.Query.SqlExpressions.CaseExpression.VisitChildren(ExpressionVisitor visitor)
   at System.Linq.Expressions.ExpressionVisitor.VisitExtension(Expression node)
   at System.Linq.Expressions.Expression.Accept(ExpressionVisitor visitor)
   at Microsoft.EntityFrameworkCore.Query.SqlExpressions.SelectExpression.SqlRemappingVisitor.Visit(Expression expression)
   at Microsoft.EntityFrameworkCore.Query.SqlExpressions.SelectExpression.SqlRemappingVisitor.Remap(SqlExpression sqlExpression)
   at Microsoft.EntityFrameworkCore.Query.SqlExpressions.SelectExpression.ApplyOrdering(OrderingExpression orderingExpression)
   at Microsoft.EntityFrameworkCore.Query.RelationalQueryableMethodTranslatingExpressionVisitor.TranslateOrderBy(ShapedQueryExpression source, LambdaExpression keySelector, Boolean ascending)
   at Microsoft.EntityFrameworkCore.Query.QueryableMethodTranslatingExpressionVisitor.VisitMethodCall(MethodCallExpression methodCallExpression)
   at System.Linq.Expressions.MethodCallExpression.Accept(ExpressionVisitor visitor)
   at System.Linq.Expressions.ExpressionVisitor.Visit(Expression node)
   at Microsoft.EntityFrameworkCore.Query.QueryableMethodTranslatingExpressionVisitor.VisitMethodCall(MethodCallExpression methodCallExpression)
   at System.Linq.Expressions.MethodCallExpression.Accept(ExpressionVisitor visitor)
   at System.Linq.Expressions.ExpressionVisitor.Visit(Expression node)
   at Microsoft.EntityFrameworkCore.Query.QueryableMethodTranslatingExpressionVisitor.VisitMethodCall(MethodCallExpression methodCallExpression)
   at System.Linq.Expressions.MethodCallExpression.Accept(ExpressionVisitor visitor)
   at System.Linq.Expressions.ExpressionVisitor.Visit(Expression node)
   at Microsoft.EntityFrameworkCore.Query.QueryCompilationContext.CreateQueryExecutor[TResult](Expression query)
   at Microsoft.EntityFrameworkCore.Storage.Database.CompileQuery[TResult](Expression query, Boolean async)
   at Microsoft.EntityFrameworkCore.Query.Internal.QueryCompiler.CompileQueryCore[TResult](IDatabase database, Expression query, IModel model, Boolean async)
   at Microsoft.EntityFrameworkCore.Query.Internal.QueryCompiler.<>c__DisplayClass9_0`1.<Execute>b__0()
   at Microsoft.EntityFrameworkCore.Query.Internal.CompiledQueryCache.GetOrAddQuery[TResult](Object cacheKey, Func`1 compiler)
   at Microsoft.EntityFrameworkCore.Query.Internal.QueryCompiler.Execute[TResult](Expression query)
   at Microsoft.EntityFrameworkCore.Query.Internal.EntityQueryProvider.Execute[TResult](Expression expression)
   at Microsoft.EntityFrameworkCore.Query.Internal.EntityQueryable`1.GetEnumerator()
   at System.Collections.Generic.List`1..ctor(IEnumerable`1 collection)
   at System.Linq.Enumerable.ToList[TSource](IEnumerable`1 source)