Minor code cleanup in SqlTranslatingEV

src/EFCore.Relational/Query/RelationalSqlTranslatingExpressionVisitor.cs

@@ -173,9 +173,9 @@ protected override Expression VisitMember(MemberExpression memberExpression)
  return result;
  }
 
- return TranslationFailed(memberExpression.Expression, innerExpression)
+ return TranslationFailed(memberExpression.Expression, innerExpression, out var sqlInnerExpression)
  ? null
- : Dependencies.MemberTranslatorProvider.Translate((SqlExpression)innerExpression, memberExpression.Member, memberExpression.Type);
+ : Dependencies.MemberTranslatorProvider.Translate(sqlInnerExpression, memberExpression.Member, memberExpression.Type);
  }
 
  private bool TryBindMember(Expression source, MemberIdentity member, out Expression expression)
@@ -329,24 +329,23 @@ protected override Expression VisitMethodCall(MethodCallExpression methodCallExp
  }
 
  // MethodCall translators
- var @object = Visit(methodCallExpression.Object);
- if (TranslationFailed(methodCallExpression.Object, @object))
+ if (TranslationFailed(methodCallExpression.Object, Visit(methodCallExpression.Object), out var sqlObject))
  {
  return null;
  }
 
  var arguments = new SqlExpression[methodCallExpression.Arguments.Count];
  for (var i = 0; i < arguments.Length; i++)
  {
- var argument = Visit(methodCallExpression.Arguments[i]);
- if (TranslationFailed(methodCallExpression.Arguments[i], argument))
+ var argument = methodCallExpression.Arguments[i];
+ if (TranslationFailed(argument, Visit(argument), out var sqlArgument))
  {
  return null;
  }
- arguments[i] = (SqlExpression)argument;
+ arguments[i] = sqlArgument;
  }
 
- return Dependencies.MethodCallTranslatorProvider.Translate(_model, (SqlExpression)@object, methodCallExpression.Method, arguments);
+ return Dependencies.MethodCallTranslatorProvider.Translate(_model, sqlObject, methodCallExpression.Method, arguments);
  }
 
  private static Expression TryRemoveImplicitConvert(Expression expression)
@@ -427,19 +426,16 @@ protected override Expression VisitBinary(BinaryExpression binaryExpression)
  var left = TryRemoveImplicitConvert(binaryExpression.Left);
  var right = TryRemoveImplicitConvert(binaryExpression.Right);
 
- left = Visit(left);
- right = Visit(right);
-
- if (TranslationFailed(binaryExpression.Left, left)
- || TranslationFailed(binaryExpression.Right, right))
+ if (TranslationFailed(binaryExpression.Left, Visit(left), out var sqlLeft)
+ || TranslationFailed(binaryExpression.Right, Visit(right), out var sqlRight))
  {
  return null;
  }
 
  return _sqlExpressionFactory.MakeBinary(
  binaryExpression.NodeType,
- (SqlExpression)left,
- (SqlExpression)right,
+ sqlLeft,
+ sqlRight,
  null);
  }
 
@@ -493,19 +489,14 @@ protected override Expression VisitConditional(ConditionalExpression conditional
  var ifTrue = Visit(conditionalExpression.IfTrue);
  var ifFalse = Visit(conditionalExpression.IfFalse);
 
- if (TranslationFailed(conditionalExpression.Test, test)
- || TranslationFailed(conditionalExpression.IfTrue, ifTrue)
- || TranslationFailed(conditionalExpression.IfFalse, ifFalse))
+ if (TranslationFailed(conditionalExpression.Test, test, out var sqlTest)
+ || TranslationFailed(conditionalExpression.IfTrue, ifTrue, out var sqlIfTrue)
+ || TranslationFailed(conditionalExpression.IfFalse, ifFalse, out var sqlIfFalse))
  {
  return null;
  }
 
- return _sqlExpressionFactory.Case(
- new[]
- {
- new CaseWhenClause((SqlExpression)test,(SqlExpression) ifTrue)
- },
- (SqlExpression)ifFalse);
+ return _sqlExpressionFactory.Case(new[] { new CaseWhenClause(sqlTest, sqlIfTrue) }, sqlIfFalse);
  }
 
  protected override Expression VisitUnary(UnaryExpression unaryExpression)
@@ -517,12 +508,11 @@ protected override Expression VisitUnary(UnaryExpression unaryExpression)
  return unaryExpression.Update(operand);
  }
 
- if (TranslationFailed(unaryExpression.Operand, operand))
+ if (TranslationFailed(unaryExpression.Operand, operand, out var sqlOperand))
  {
  return null;
  }
 
- var sqlOperand = (SqlExpression)operand;
  switch (unaryExpression.NodeType)
  {
  case ExpressionType.Not:
@@ -557,7 +547,16 @@ protected override Expression VisitUnary(UnaryExpression unaryExpression)
  }
 
  [DebuggerStepThrough]
- private bool TranslationFailed(Expression original, Expression translation)
- => original != null && !(translation is SqlExpression);
+ private bool TranslationFailed(Expression original, Expression translation, out SqlExpression castTranslation)
+ {
+ if (original != null && !(translation is SqlExpression))
+ {
+ castTranslation = null;
+ return true;
+ }
+
+ castTranslation = translation as SqlExpression;
+ return false;
+ }
  }
 }