public IEnumerable <TNodeOrToken> QueryAll(TNodeOrToken current, SyntaxQuery query)
{
switch (query.Axis)
{
case SyntaxQueryAxis.Self:
return(QuerySelf(current, query));
case SyntaxQueryAxis.Child:
return(QueryAllChildrenOrDescendants(current, query, descendants: false));
case SyntaxQueryAxis.Descendant:
return(QueryAllChildrenOrDescendants(current, query, descendants: true));
case SyntaxQueryAxis.Parent:
var parent = ToNodeOrToken(GetParent(current));
if (MatchesIgnoringAxis(parent, query))
{
return(Enumerable.Repeat(parent, 1));
}
return(Enumerable.Empty <TNodeOrToken>());
default:
throw new ArgumentException($"Unsupported query axis: {query.Axis}.", nameof(query));
}
}
private bool MatchesIgnoringAxis(TNodeOrToken node, SyntaxQuery query)
{
if (IsExpressionStatement(node, out var expression))
{
return(MatchesIgnoringAxis(ToNodeOrToken(expression), query));
}
if (IsSwitchSection(node, out var labels))
{
foreach (var label in labels)
{
if (MatchesNodeTypeAndFilter(node, ToNodeOrToken(label), query))
{
return(true);
}
}
}
if (IsPredefinedType(node, out var keyword))
{
return(MatchesNodeTypeAndFilter(node, keyword, query));
}
if (HasOtherNodeTypeDefiningChildNode(node, out var nodeTypeChild))
{
return(MatchesNodeTypeAndFilter(node, nodeTypeChild, query));
}
return(MatchesNodeTypeAndFilter(node, node, query));
}
private IEnumerable <TNodeOrToken> QuerySelf(TNodeOrToken nodeOrToken, SyntaxQuery query)
{
var node = AsNode(nodeOrToken);
if (node != null && ShouldJumpOver(node))
{
foreach (var child in GetChildren(nodeOrToken, noFirstJump: true))
{
if (MatchesIgnoringAxis(child, query))
{
yield return(child);
}
}
yield break;
}
if (MatchesIgnoringAxis(nodeOrToken, query))
{
yield return(nodeOrToken);
}
}
private IEnumerable <TNodeOrToken> QueryAllChildrenOrDescendants(TNodeOrToken node, SyntaxQuery query, bool descendants)
{
foreach (var child in GetChildren(node))
{
if (MatchesIgnoringAxis(child, query))
{
yield return(child);
continue;
}
if (descendants)
{
foreach (var descendant in QueryAllChildrenOrDescendants(child, query, descendants: true))
{
yield return(descendant);
}
}
}
}
protected abstract bool MatchesNodeType(TNodeOrToken node, SyntaxQuery query);
private bool MatchesNodeTypeAndFilter(TNodeOrToken node, TNodeOrToken typeFromNode, SyntaxQuery query)
{
return(MatchesNodeType(typeFromNode, query) &&
MatchesFilter(node, query.Filter));
}