private static IList <TagHelperAttributeNode> GetTagAttributes(
string tagName,
bool validStructure,
Block tagBlock,
TagHelperBinding bindingResult,
ErrorSink errorSink)
{
var attributes = new List <TagHelperAttributeNode>();
// We skip the first child "<tagname" and take everything up to the ending portion of the tag ">" or "/>".
// The -2 accounts for both the start and end tags. If the tag does not have a valid structure then there's
// no end tag to ignore.
var symbolOffset = validStructure ? 2 : 1;
var attributeChildren = tagBlock.Children.Skip(1).Take(tagBlock.Children.Count() - symbolOffset);
var processedBoundAttributeNames = new HashSet <string>(StringComparer.OrdinalIgnoreCase);
foreach (var child in attributeChildren)
{
TryParseResult result;
if (child.IsBlock)
{
result = TryParseBlock(tagName, (Block)child, bindingResult.Descriptors, errorSink, processedBoundAttributeNames);
}
else
{
result = TryParseSpan((Span)child, bindingResult.Descriptors, errorSink, processedBoundAttributeNames);
}
// Only want to track the attribute if we succeeded in parsing its corresponding Block/Span.
if (result != null)
{
SourceLocation?errorLocation = null;
// Check if it's a bound attribute that is minimized or if it's a bound non-string attribute that
// is null or whitespace.
if ((result.IsBoundAttribute && result.AttributeValueNode == null) ||
(result.IsBoundNonStringAttribute &&
IsNullOrWhitespaceAttributeValue(result.AttributeValueNode)))
{
errorLocation = GetAttributeNameStartLocation(child);
errorSink.OnError(
errorLocation.Value,
LegacyResources.FormatRewriterError_EmptyTagHelperBoundAttribute(
result.AttributeName,
tagName,
GetPropertyType(result.AttributeName, bindingResult.Descriptors)),
result.AttributeName.Length);
}
// Check if the attribute was a prefix match for a tag helper dictionary property but the
// dictionary key would be the empty string.
if (result.IsMissingDictionaryKey)
{
if (!errorLocation.HasValue)
{
errorLocation = GetAttributeNameStartLocation(child);
}
errorSink.OnError(
errorLocation.Value,
LegacyResources.FormatTagHelperBlockRewriter_IndexerAttributeNameMustIncludeKey(
result.AttributeName,
tagName),
result.AttributeName.Length);
}
var attributeNode = new TagHelperAttributeNode(
result.AttributeName,
result.AttributeValueNode,
result.AttributeStructure);
attributes.Add(attributeNode);
}
else
{
// Error occured while parsing the attribute. Don't try parsing the rest to avoid misleading errors.
break;
}
}
return(attributes);
}
