Cosmos: Avoid reading default values from database (#21821)

Resolves #21678

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

@@ -385,7 +385,10 @@ protected override ShapedQueryExpression TranslateCount(ShapedQueryExpression so
 
  selectExpression.ClearOrdering();
  selectExpression.ReplaceProjectionMapping(projectionMapping);
- return source.UpdateShaperExpression(new ProjectionBindingExpression(source.QueryExpression, new ProjectionMember(), typeof(int)));
+ return source.UpdateShaperExpression(
+ Expression.Convert(
+ new ProjectionBindingExpression(source.QueryExpression, new ProjectionMember(), typeof(int?)),
+ typeof(int)));
  }
 
  /// <summary>
@@ -631,7 +634,10 @@ protected override ShapedQueryExpression TranslateLongCount(ShapedQueryExpressio
 
  selectExpression.ClearOrdering();
  selectExpression.ReplaceProjectionMapping(projectionMapping);
- return source.UpdateShaperExpression(new ProjectionBindingExpression(source.QueryExpression, new ProjectionMember(), typeof(long)));
+ return source.UpdateShaperExpression(
+ Expression.Convert(
+ new ProjectionBindingExpression(source.QueryExpression, new ProjectionMember(), typeof(long?)),
+ typeof(long)));
  }
 
  /// <summary>
@@ -1132,8 +1138,7 @@ private ShapedQueryExpression AggregateResultShaper(
  selectExpression.ClearOrdering();
 
  var nullableResultType = resultType.MakeNullable();
- Expression shaper = new ProjectionBindingExpression(
- source.QueryExpression, new ProjectionMember(), throwOnNullResult ? nullableResultType : projection.Type);
+ Expression shaper = new ProjectionBindingExpression(source.QueryExpression, new ProjectionMember(), nullableResultType);
 
  if (throwOnNullResult)
  {

src/EFCore.Cosmos/Query/Internal/CosmosShapedQueryCompilingExpressionVisitor.CosmosProjectionBindingRemovingExpressionVisitorBase.cs

@@ -640,7 +640,9 @@ private Expression CreateGetValueExpression(
  return Expression.Default(clrType);
  }
 
- return CreateGetValueExpression(jObjectExpression, storeName, clrType, property.GetTypeMapping());
+ return Expression.Convert(
+ CreateGetValueExpression(jObjectExpression, storeName, clrType.MakeNullable(), property.GetTypeMapping()),
+ clrType);
  }
 
  private Expression CreateGetValueExpression(
@@ -649,6 +651,8 @@ private Expression CreateGetValueExpression(
  Type clrType,
  CoreTypeMapping typeMapping = null)
  {
+ Check.DebugAssert(clrType.IsNullableType(), "Must read nullable type from JObject.");
+
  var innerExpression = jObjectExpression;
  if (_projectionBindings.TryGetValue(jObjectExpression, out var innerVariable))
  {

src/EFCore.Relational/Query/Internal/RelationalProjectionBindingExpressionVisitor.cs

@@ -30,6 +30,7 @@ private static readonly MethodInfo _getParameterValueMethodInfo
 
  private readonly RelationalQueryableMethodTranslatingExpressionVisitor _queryableMethodTranslatingExpressionVisitor;
  private readonly RelationalSqlTranslatingExpressionVisitor _sqlTranslator;
+ private readonly IncludeFindingExpressionVisitor _includeFindingExpressionVisitor;
 
  private SelectExpression _selectExpression;
  private SqlExpression[] _existingProjections;
@@ -52,6 +53,7 @@ public RelationalProjectionBindingExpressionVisitor(
  {
  _queryableMethodTranslatingExpressionVisitor = queryableMethodTranslatingExpressionVisitor;
  _sqlTranslator = sqlTranslatingExpressionVisitor;
+ _includeFindingExpressionVisitor = new IncludeFindingExpressionVisitor();
  }
 
  /// <summary>
@@ -367,7 +369,8 @@ protected override Expression VisitMember(MemberExpression memberExpression)
  Expression updatedMemberExpression = memberExpression.Update(
  expression != null ? MatchTypes(expression, memberExpression.Expression.Type) : expression);
 
- if (expression?.Type.IsNullableValueType() == true)
+ if (expression?.Type.IsNullableType() == true
+ && !_includeFindingExpressionVisitor.ContainsInclude(expression))
  {
  var nullableReturnType = memberExpression.Type.MakeNullable();
  if (!memberExpression.Type.IsNullableType())
@@ -591,5 +594,33 @@ private static Expression MatchTypes(Expression expression, Type targetType)
  private static T GetParameterValue<T>(QueryContext queryContext, string parameterName)
 #pragma warning restore IDE0052 // Remove unread private members
  => (T)queryContext.ParameterValues[parameterName];
+
+ private sealed class IncludeFindingExpressionVisitor : ExpressionVisitor
+ {
+ private bool _containsInclude;
+
+ public bool ContainsInclude(Expression expression)
+ {
+ _containsInclude = false;
+
+ Visit(expression);
+
+ return _containsInclude;
+ }
+
+ public override Expression Visit(Expression expression) => _containsInclude ? expression : base.Visit(expression);
+
+ protected override Expression VisitExtension(Expression extensionExpression)
+ {
+ if (extensionExpression is IncludeExpression)
+ {
+ _containsInclude = true;
+
+ return extensionExpression;
+ }
+
+ return base.VisitExtension(extensionExpression);
+ }
+ }
  }
 }

test/EFCore.Cosmos.FunctionalTests/BuiltInDataTypesCosmosTest.cs

@@ -80,12 +80,6 @@ FROM root c
 WHERE ((c[""Discriminator""] = ""BuiltInDataTypes"") AND (c[""Id""] = 13))");
  }
 
- [ConditionalFact(Skip = "Issue#21678")]
- public override void Optional_datetime_reading_null_from_database()
- {
- base.Optional_datetime_reading_null_from_database();
- }
-
  private void AssertSql(params string[] expected)
  => Fixture.TestSqlLoggerFactory.AssertBaseline(expected);
 

test/EFCore.Cosmos.FunctionalTests/CustomConvertersCosmosTest.cs

@@ -152,12 +152,6 @@ public override void Optional_owned_with_converter_reading_non_nullable_column()
  base.Optional_owned_with_converter_reading_non_nullable_column();
  }
 
- [ConditionalFact(Skip = "Issue#21678")]
- public override void Optional_datetime_reading_null_from_database()
- {
- base.Optional_datetime_reading_null_from_database();
- }
-
  private void AssertSql(params string[] expected)
  => Fixture.TestSqlLoggerFactory.AssertBaseline(expected);
 

test/EFCore.Cosmos.FunctionalTests/Query/NorthwindMiscellaneousQueryCosmosTest.cs

@@ -2308,12 +2308,10 @@ FROM root c
 WHERE (c[""Discriminator""] = ""Customer"")");
  }
 
+ [ConditionalTheory(Skip = "Issue#13168")]
  public override Task Where_bitwise_or_with_logical_or(bool async)
  {
- // #13168
- //await base.Where_bitwise_or_with_logical_or(async);
-
- return Task.CompletedTask;
+ return base.Where_bitwise_or_with_logical_or(async);
  }
 
  public override async Task Where_bitwise_and_with_logical_and(bool async)
@@ -2326,12 +2324,10 @@ FROM root c
 WHERE ((c[""Discriminator""] = ""Customer"") AND (((c[""CustomerID""] = ""ALFKI"") & (c[""CustomerID""] = ""ANATR"")) AND (c[""CustomerID""] = ""ANTON"")))");
  }
 
+ [ConditionalTheory(Skip = "Issue#13168")]
  public override Task Where_bitwise_or_with_logical_and(bool async)
  {
- // #13168
- //await base.Where_bitwise_or_with_logical_and(async);
-
- return Task.CompletedTask;
+ return base.Where_bitwise_or_with_logical_and(async);
  }
 
  public override async Task Where_bitwise_and_with_logical_or(bool async)
@@ -2409,12 +2405,10 @@ FROM root c
 WHERE (c[""Discriminator""] = ""Customer"")");
  }
 
+ [ConditionalTheory(Skip = "Issue#13159")]
  public override Task Parameter_extraction_short_circuits_1(bool async)
  {
- // #13159
- //await base.Parameter_extraction_short_circuits_1(async);
-
- return Task.CompletedTask;
+ return base.Parameter_extraction_short_circuits_1(async);
  }
 
  [ConditionalTheory(Skip = "Issue #17246")]
@@ -2428,12 +2422,10 @@ FROM root c
 WHERE (c[""Discriminator""] = ""Order"")");
  }
 
+ [ConditionalTheory(Skip = "Issue#13159")]
  public override Task Parameter_extraction_short_circuits_3(bool async)
  {
- // #13159
- //await base.Parameter_extraction_short_circuits_3(async);
-
- return Task.CompletedTask;
+ return base.Parameter_extraction_short_circuits_3(async);
  }
 
  [ConditionalTheory(Skip = "Issue #17246")]
@@ -4151,24 +4143,18 @@ public override Task Select_distinct_Select_with_client_bindings(bool async)
  return base.Select_distinct_Select_with_client_bindings(async);
  }
 
- [ConditionalTheory(Skip = "Issue#21678")]
- public override Task Non_nullable_property_through_optional_navigation(bool async)
+ [ConditionalTheory(Skip = "Non embedded collection subquery Issue#17246")]
+ public override Task Pending_selector_in_cardinality_reducing_method_is_applied_before_expanding_collection_navigation_member(bool async)
  {
- return base.Non_nullable_property_through_optional_navigation(async);
+ return base.Pending_selector_in_cardinality_reducing_method_is_applied_before_expanding_collection_navigation_member(async);
  }
 
- [ConditionalTheory(Skip = "Issue#21678")]
+ [ConditionalTheory(Skip = "Non embedded collection subquery Issue#17246")]
  public override Task Max_on_empty_sequence_throws(bool async)
  {
  return base.Max_on_empty_sequence_throws(async);
  }
 
- [ConditionalTheory(Skip = "Non embedded collection subquery Issue#17246")]
- public override Task Pending_selector_in_cardinality_reducing_method_is_applied_before_expanding_collection_navigation_member(bool async)
- {
- return base.Pending_selector_in_cardinality_reducing_method_is_applied_before_expanding_collection_navigation_member(async);
- }
-
  private void AssertSql(params string[] expected)
  => Fixture.TestSqlLoggerFactory.AssertBaseline(expected);