private void ValidateParentAllowsPlainTag(MarkupTagBlockSyntax tagBlock)
{
var tagName = tagBlock.GetTagName();
// Treat partial tags such as '</' which have no tag names as content.
if (string.IsNullOrEmpty(tagName))
{
var firstChild = tagBlock.Children.First();
Debug.Assert(firstChild is MarkupTextLiteralSyntax || firstChild is MarkupTransitionSyntax);
ValidateParentAllowsContent(tagBlock.Children.First());
return;
}
if (!HasAllowedChildren())
{
return;
}
var tagHelperBinding = _tagHelperBinder.GetBinding(
tagName,
attributes: Array.Empty <KeyValuePair <string, string> >(),
parentTagName: CurrentParentTagName,
parentIsTagHelper: CurrentParentIsTagHelper);
// If we found a binding for the current tag, then it is a tag helper. Use the prefixed allowed children to compare.
var allowedChildren = tagHelperBinding != null ? CurrentTagHelperTracker.PrefixedAllowedChildren : CurrentTagHelperTracker.AllowedChildren;
if (!allowedChildren.Contains(tagName, StringComparer.OrdinalIgnoreCase))
{
OnAllowedChildrenTagError(CurrentTagHelperTracker, tagName, tagBlock, _errorSink, _source);
}
}
public static bool IsVoidElement(this MarkupTagBlockSyntax tagBlock)
{
if (tagBlock == null)
{
throw new ArgumentNullException(nameof(tagBlock));
}
return(VoidElements.Contains(tagBlock.GetTagName()));
}
public TagBlockTracker(MarkupTagBlockSyntax tagBlock)
{
TagBlock = tagBlock;
TagName = tagBlock.GetTagName();
Children = new List <RazorSyntaxNode>();
}
private bool TryRewriteTagHelperEnd(MarkupTagBlockSyntax tagBlock, out MarkupTagHelperEndTagSyntax rewritten)
{
rewritten = null;
var tagName = tagBlock.GetTagName();
// Could not determine tag name, it can't be a TagHelper, continue on and track the element.
if (tagName == null)
{
return(false);
}
var tracker = CurrentTagHelperTracker;
var tagNameScope = tracker?.TagName ?? string.Empty;
if (!IsPotentialTagHelper(tagName, tagBlock))
{
return(false);
}
// Validate that our end tag matches the currently scoped tag, if not we may need to error.
if (tagNameScope.Equals(tagName, StringComparison.OrdinalIgnoreCase))
{
// If there are additional end tags required before we can build our block it means we're in a
// situation like this: <myth req="..."><myth></myth></myth> where we're at the inside </myth>.
if (tracker.OpenMatchingTags > 0)
{
tracker.OpenMatchingTags--;
return(false);
}
ValidateTagSyntax(tagName, tagBlock);
_trackerStack.Pop();
}
else
{
var tagHelperBinding = _tagHelperBinder.GetBinding(
tagName,
attributes: Array.Empty <KeyValuePair <string, string> >(),
parentTagName: CurrentParentTagName,
parentIsTagHelper: CurrentParentIsTagHelper);
// If there are not TagHelperDescriptors associated with the end tag block that also have no
// required attributes then it means we can't be a TagHelper, bail out.
if (tagHelperBinding == null)
{
return(false);
}
foreach (var descriptor in tagHelperBinding.Descriptors)
{
var boundRules = tagHelperBinding.GetBoundRules(descriptor);
var invalidRule = boundRules.FirstOrDefault(rule => rule.TagStructure == TagStructure.WithoutEndTag);
if (invalidRule != null)
{
// End tag TagHelper that states it shouldn't have an end tag.
_errorSink.OnError(
RazorDiagnosticFactory.CreateParsing_TagHelperMustNotHaveAnEndTag(
new SourceSpan(SourceLocationTracker.Advance(tagBlock.GetSourceLocation(_source), "</"), tagName.Length),
tagName,
descriptor.DisplayName,
invalidRule.TagStructure));
return(false);
}
}
}
rewritten = SyntaxFactory.MarkupTagHelperEndTag(tagBlock.Children);
return(true);
}
private bool TryRewriteTagHelperStart(MarkupTagBlockSyntax tagBlock, out MarkupTagHelperStartTagSyntax rewritten, out TagHelperInfo tagHelperInfo)
{
rewritten = null;
tagHelperInfo = null;
// Get tag name of the current block
var tagName = tagBlock.GetTagName();
// Could not determine tag name, it can't be a TagHelper, continue on and track the element.
if (tagName == null)
{
return(false);
}
TagHelperBinding tagHelperBinding;
if (!IsPotentialTagHelper(tagName, tagBlock))
{
return(false);
}
var tracker = CurrentTagHelperTracker;
var tagNameScope = tracker?.TagName ?? string.Empty;
// We're now in a start tag block, we first need to see if the tag block is a tag helper.
var elementAttributes = GetAttributeNameValuePairs(tagBlock);
tagHelperBinding = _tagHelperBinder.GetBinding(
tagName,
elementAttributes,
CurrentParentTagName,
CurrentParentIsTagHelper);
// If there aren't any TagHelperDescriptors registered then we aren't a TagHelper
if (tagHelperBinding == null)
{
// If the current tag matches the current TagHelper scope it means the parent TagHelper matched
// all the required attributes but the current one did not; therefore, we need to increment the
// OpenMatchingTags counter for current the TagHelperBlock so we don't end it too early.
// ex: <myth req="..."><myth></myth></myth> We don't want the first myth to close on the inside
// tag.
if (string.Equals(tagNameScope, tagName, StringComparison.OrdinalIgnoreCase))
{
tracker.OpenMatchingTags++;
}
return(false);
}
ValidateParentAllowsTagHelper(tagName, tagBlock);
ValidateBinding(tagHelperBinding, tagName, tagBlock);
// We're in a start TagHelper block.
var validTagStructure = ValidateTagSyntax(tagName, tagBlock);
var startTag = TagHelperBlockRewriter.Rewrite(
tagName,
validTagStructure,
_featureFlags,
tagBlock,
tagHelperBinding,
_errorSink,
_source);
var tagMode = TagHelperBlockRewriter.GetTagMode(tagBlock, tagHelperBinding, _errorSink);
tagHelperInfo = new TagHelperInfo(tagName, tagMode, tagHelperBinding);
rewritten = startTag;
return(true);
}