private (Expression operand, NavigationExpansionExpressionState state) ApplyIncludes(NavigationExpansionExpression navigationExpansionExpression)
{
var includeFinder = new PendingIncludeFindingVisitor();
includeFinder.Visit(navigationExpansionExpression.State.PendingSelector.Body);
var includeRewriter = new PendingSelectorIncludeRewriter();
var rewrittenBody = includeRewriter.Visit(navigationExpansionExpression.State.PendingSelector.Body);
if (navigationExpansionExpression.State.PendingSelector.Body != rewrittenBody)
{
navigationExpansionExpression.State.PendingSelector = Expression.Lambda(rewrittenBody, navigationExpansionExpression.State.PendingSelector.Parameters[0]);
navigationExpansionExpression.State.ApplyPendingSelector = true;
}
if (includeFinder.PendingIncludes.Count > 0)
{
var result = (source : navigationExpansionExpression.Operand, parameter : navigationExpansionExpression.State.CurrentParameter);
foreach (var pendingIncludeNode in includeFinder.PendingIncludes)
{
result = NavigationExpansionHelpers.AddNavigationJoin(
result.source,
result.parameter,
pendingIncludeNode.Value,
pendingIncludeNode.Key,
navigationExpansionExpression.State,
new List <INavigation>(),
include: true);
}
var pendingSelector = navigationExpansionExpression.State.PendingSelector;
if (navigationExpansionExpression.State.CurrentParameter != result.parameter)
{
var pendingSelectorBody = new ExpressionReplacingVisitor(navigationExpansionExpression.State.CurrentParameter, result.parameter).Visit(navigationExpansionExpression.State.PendingSelector.Body);
pendingSelector = Expression.Lambda(pendingSelectorBody, result.parameter);
}
var newState = new NavigationExpansionExpressionState(
result.parameter,
navigationExpansionExpression.State.SourceMappings,
pendingSelector,
applyPendingSelector: true,
navigationExpansionExpression.State.PendingOrderings,
navigationExpansionExpression.State.PendingIncludeChain,
navigationExpansionExpression.State.PendingCardinalityReducingOperator,
navigationExpansionExpression.State.PendingTags,
navigationExpansionExpression.State.CustomRootMappings,
navigationExpansionExpression.State.MaterializeCollectionNavigation);
return(operand : result.source, state : newState);
}
return(operand : navigationExpansionExpression.Operand, state : navigationExpansionExpression.State);
}
protected override Expression VisitExtension(Expression extensionExpression)
{
if (extensionExpression is NavigationBindingExpression navigationBindingExpression)
{
var result = navigationBindingExpression.RootParameter.BuildPropertyAccess(navigationBindingExpression.NavigationTreeNode.ToMapping);
return(result);
}
if (extensionExpression is NavigationExpansionRootExpression navigationExpansionRootExpression)
{
return(Visit(navigationExpansionRootExpression.Unwrap()));
}
if (extensionExpression is NavigationExpansionExpression navigationExpansionExpression)
{
var includeResult = ApplyIncludes(navigationExpansionExpression);
var state = includeResult.state;
var result = Visit(includeResult.operand);
if (!state.ApplyPendingSelector &&
state.PendingOrderings.Count == 0 &&
state.PendingTags.Count == 0 &&
state.PendingCardinalityReducingOperator == null &&
state.MaterializeCollectionNavigation == null)
{
return(result);
}
var parameter = Expression.Parameter(result.Type.GetSequenceType());
foreach (var pendingOrdering in state.PendingOrderings)
{
var remappedKeySelectorBody = new ExpressionReplacingVisitor(pendingOrdering.keySelector.Parameters[0], state.CurrentParameter).Visit(pendingOrdering.keySelector.Body);
var newSelectorBody = new NavigationPropertyUnbindingVisitor(state.CurrentParameter).Visit(remappedKeySelectorBody);
var newSelector = Expression.Lambda(newSelectorBody, state.CurrentParameter);
var orderingMethod = pendingOrdering.method.MakeGenericMethod(state.CurrentParameter.Type, newSelectorBody.Type);
result = Expression.Call(orderingMethod, result, newSelector);
}
if (state.ApplyPendingSelector)
{
var pendingSelector = (LambdaExpression) new NavigationPropertyUnbindingVisitor(state.CurrentParameter).Visit(state.PendingSelector);
var pendingSelectorBodyType = pendingSelector.Type.GetGenericArguments()[1];
var pendingSelectMathod = result.Type.IsGenericType && (result.Type.GetGenericTypeDefinition() == typeof(IEnumerable <>) || result.Type.GetGenericTypeDefinition() == typeof(IOrderedEnumerable <>))
? LinqMethodHelpers.EnumerableSelectMethodInfo.MakeGenericMethod(parameter.Type, pendingSelectorBodyType)
: LinqMethodHelpers.QueryableSelectMethodInfo.MakeGenericMethod(parameter.Type, pendingSelectorBodyType);
result = Expression.Call(pendingSelectMathod, result, pendingSelector);
parameter = Expression.Parameter(result.Type.GetSequenceType());
}
if (state.PendingTags.Count > 0)
{
var withTagMethodInfo = EntityFrameworkQueryableExtensions.TagWithMethodInfo.MakeGenericMethod(parameter.Type);
foreach (var pendingTag in state.PendingTags)
{
result = Expression.Call(withTagMethodInfo, result, Expression.Constant(pendingTag));
}
}
if (state.PendingCardinalityReducingOperator != null)
{
var terminatingOperatorMethodInfo = state.PendingCardinalityReducingOperator.MakeGenericMethod(parameter.Type);
result = Expression.Call(terminatingOperatorMethodInfo, result);
}
if (state.MaterializeCollectionNavigation != null)
{
var entityType = state.MaterializeCollectionNavigation.ClrType.IsGenericType
? state.MaterializeCollectionNavigation.ClrType.GetGenericArguments()[0]
: state.MaterializeCollectionNavigation.GetTargetType().ClrType;
result = Expression.Call(
NavigationExpansionHelpers.MaterializeCollectionNavigationMethodInfo.MakeGenericMethod(
state.MaterializeCollectionNavigation.ClrType,
entityType),
result,
Expression.Constant(state.MaterializeCollectionNavigation));
}
if (navigationExpansionExpression.Type != result.Type && navigationExpansionExpression.Type.IsGenericType)
{
if (navigationExpansionExpression.Type.GetGenericTypeDefinition() == typeof(IOrderedQueryable <>))
{
var toOrderedQueryableMethodInfo = ToOrderedQueryableMethod.MakeGenericMethod(parameter.Type);
return(Expression.Call(toOrderedQueryableMethodInfo, result));
}
else if (navigationExpansionExpression.Type.GetGenericTypeDefinition() == typeof(IOrderedEnumerable <>))
{
var toOrderedEnumerableMethodInfo = ToOrderedEnumerableMethod.MakeGenericMethod(parameter.Type);
return(Expression.Call(toOrderedEnumerableMethodInfo, result));
}
}
return(result);
}
return(base.VisitExtension(extensionExpression));
}
protected override Expression VisitExtension(Expression extensionExpression)
{
switch (extensionExpression)
{
case NavigationBindingExpression navigationBindingExpression:
return(navigationBindingExpression.RootParameter.BuildPropertyAccess(
navigationBindingExpression.NavigationTreeNode.ToMapping));
case NavigationExpansionRootExpression navigationExpansionRootExpression:
return(Visit(navigationExpansionRootExpression.Unwrap()));
case NavigationExpansionExpression navigationExpansionExpression:
{
var(result, state) = ApplyIncludes(navigationExpansionExpression);
result = Visit(result);
if (!state.ApplyPendingSelector &&
state.PendingOrderings.Count == 0 &&
state.PendingCardinalityReducingOperator == null &&
state.MaterializeCollectionNavigation == null)
{
return(result);
}
var parameterType = result.Type.GetSequenceType();
foreach (var pendingOrdering in state.PendingOrderings)
{
var remappedKeySelectorBody = new ExpressionReplacingVisitor(pendingOrdering.keySelector.Parameters[0], state.CurrentParameter).Visit(pendingOrdering.keySelector.Body);
var newSelectorBody = new NavigationPropertyUnbindingVisitor(state.CurrentParameter).Visit(remappedKeySelectorBody);
var newSelector = Expression.Lambda(newSelectorBody, state.CurrentParameter);
var orderingMethod = pendingOrdering.method.MakeGenericMethod(state.CurrentParameter.Type, newSelectorBody.Type);
result = Expression.Call(orderingMethod, result, newSelector);
}
if (state.ApplyPendingSelector)
{
var pendingSelector = (LambdaExpression) new NavigationPropertyUnbindingVisitor(state.CurrentParameter).Visit(state.PendingSelector);
var pendingSelectorBodyType = pendingSelector.Type.GetGenericArguments()[1];
var pendingSelectMethod = result.Type.IsGenericType && (result.Type.GetGenericTypeDefinition() == typeof(IEnumerable <>) || result.Type.GetGenericTypeDefinition() == typeof(IOrderedEnumerable <>))
? LinqMethodHelpers.EnumerableSelectMethodInfo.MakeGenericMethod(parameterType, pendingSelectorBodyType)
: LinqMethodHelpers.QueryableSelectMethodInfo.MakeGenericMethod(parameterType, pendingSelectorBodyType);
result = Expression.Call(pendingSelectMethod, result, pendingSelector);
parameterType = result.Type.GetSequenceType();
}
if (state.PendingCardinalityReducingOperator != null)
{
result = Expression.Call(state.PendingCardinalityReducingOperator, result);
}
if (state.MaterializeCollectionNavigation != null)
{
result = new MaterializeCollectionNavigationExpression(result, state.MaterializeCollectionNavigation);
}
if (navigationExpansionExpression.Type != result.Type && navigationExpansionExpression.Type.IsGenericType)
{
if (navigationExpansionExpression.Type.GetGenericTypeDefinition() == typeof(IOrderedQueryable <>))
{
var toOrderedQueryableMethodInfo = ToOrderedQueryableMethod.MakeGenericMethod(parameterType);
return(Expression.Call(toOrderedQueryableMethodInfo, result));
}
if (navigationExpansionExpression.Type.GetGenericTypeDefinition() == typeof(IOrderedEnumerable <>))
{
var toOrderedEnumerableMethodInfo = ToOrderedEnumerableMethod.MakeGenericMethod(parameterType);
return(Expression.Call(toOrderedEnumerableMethodInfo, result));
}
}
return(result);
}
}
return(base.VisitExtension(extensionExpression));
}
