public virtual SyntaxTokenList VisitList(SyntaxTokenList list)
{
SyntaxTokenListBuilder alternate = null;
var count = list.Count;
var index = -1;
foreach (var item in list)
{
index++;
var visited = this.VisitToken(item);
if (item != visited && alternate == null)
{
alternate = new SyntaxTokenListBuilder(count);
alternate.Add(list, 0, index);
}
if (alternate != null && visited.CSharpKind() != SyntaxKind.None) //skip the null check since SyntaxToken is a value type
{
alternate.Add(visited);
}
}
if (alternate != null)
{
return(alternate.ToList());
}
return(list);
}
/// <summary>
/// Insert one or more tokens in the list at the specified index.
/// </summary>
/// <returns>A new list with the tokens inserted.</returns>
public static SyntaxTokenList Insert(this SyntaxTokenList list, int index, params SyntaxToken[] items)
{
if (index < 0 || index > list.Count)
{
throw new ArgumentOutOfRangeException(nameof(index));
}
if (items == null)
{
throw new ArgumentNullException(nameof(items));
}
if (items.Length == 0)
{
return(list);
}
if (list.Count == 0)
{
var first = (Syntax.InternalSyntax.InternalSyntaxToken)items[0].Node;
return(first.Language.SyntaxFactory.TokenList(items));
}
else
{
var builder = new SyntaxTokenListBuilder(list.Count + items.Length);
if (index > 0)
{
builder.Add(list, 0, index);
}
builder.Add(items);
if (index < list.Count)
{
builder.Add(list, index, list.Count - index);
}
return(builder.ToList());
}
}
private static GreenNode CreateNode(SyntaxToken[] tokens)
{
if (tokens == null)
{
return(null);
}
// TODO: we could remove the unnecessary builder allocations here and go directly
// from the array to the List nodes.
var builder = new SyntaxTokenListBuilder(tokens.Length);
for (int i = 0; i < tokens.Length; i++)
{
builder.Add(tokens[i].Node);
}
return(builder.ToList().Node);
}