private void ProcessDuplicates(IntermediateNode parent)
{
// Reverse order because we will remove nodes.
//
// Each 'property' node could be duplicated if there are multiple tag helpers that match that
// particular attribute. This is likely to happen when a component also defines something like
// OnClick. We want to remove the 'onclick' and let it fall back to be handled by the component.
for (var i = parent.Children.Count - 1; i >= 0; i--)
{
var eventHandler = parent.Children[i] as TagHelperPropertyIntermediateNode;
if (eventHandler != null &&
eventHandler.TagHelper != null &&
eventHandler.TagHelper.IsEventHandlerTagHelper())
{
for (var j = 0; j < parent.Children.Count; j++)
{
var componentAttribute = parent.Children[j] as ComponentAttributeIntermediateNode;
if (componentAttribute != null &&
componentAttribute.TagHelper != null &&
componentAttribute.TagHelper.IsComponentTagHelper() &&
componentAttribute.AttributeName == eventHandler.AttributeName)
{
// Found a duplicate - remove the 'fallback' in favor of the component's own handling.
parent.Children.RemoveAt(i);
break;
}
}
}
}
// If we still have duplicates at this point then they are genuine conflicts.
var duplicates = parent.Children
.OfType <TagHelperDirectiveAttributeIntermediateNode>()
.Where(p => p.TagHelper?.IsEventHandlerTagHelper() ?? false)
.GroupBy(p => p.AttributeName)
.Where(g => g.Count() > 1);
foreach (var duplicate in duplicates)
{
parent.Diagnostics.Add(ComponentDiagnosticFactory.CreateEventHandler_Duplicates(
parent.Source,
duplicate.Key,
duplicate.ToArray()));
foreach (var property in duplicate)
{
parent.Children.Remove(property);
}
}
var parameterDuplicates = parent.Children
.OfType <TagHelperDirectiveAttributeParameterIntermediateNode>()
.Where(p => p.TagHelper?.IsEventHandlerTagHelper() ?? false)
.GroupBy(p => p.AttributeName)
.Where(g => g.Count() > 1);
foreach (var duplicate in parameterDuplicates)
{
parent.Diagnostics.Add(ComponentDiagnosticFactory.CreateEventHandlerParameter_Duplicates(
parent.Source,
duplicate.Key,
duplicate.ToArray()));
foreach (var property in duplicate)
{
parent.Children.Remove(property);
}
}
}
