Ast.Entry GetEntryOrJunk(FtlParserStream ps)
{
var entryStartPos = ps.GetPosition();
ps.BeginCapture();
try
{
var entry = GetEntry(ps);
ps.ExpectNewLine();
return(entry);
}
catch (ParseException e)
{
var errorPos = ps.GetPosition();
ps.SkipToNextEntryStart();
var nextEntryStart = ps.GetPosition();
// Create a Junk instance
var junk = new Ast.Junk(ps.GetCapturedText());
if (_withSpans)
{
junk.AddSpan(entryStartPos, nextEntryStart);
}
var annot = new Ast.Annotation(e.Code, e.Args, e.Message);
annot.AddSpan(errorPos, errorPos);
junk.AddAnnotation(annot);
return(junk);
}
}
public Ast.Resource Parse(TextReader input)
{
var ps = new FtlParserStream(input);
ps.SkipBlankLines();
var entries = new List <Ast.Entry>();
Ast.Comment lastComment = null;
while (ps.Current != Eof)
{
var entry = GetEntryOrJunk(ps);
int blankLines = ps.SkipBlankLines();
// Regular Comments require special logic. Comments may be attached to
// Messages or Terms if they are followed immediately by them. However
// they should parse as standalone when they're followed by Junk.
// Consequently, we only attach Comments once we know that the Message
// or the Term parsed successfully.
if (entry is Ast.Comment comment &&
blankLines == 0 && ps.Current != Eof)
{
// Stash the comment and decide what to do with it in the next pass.
lastComment = comment;
continue;
}
if (lastComment != null)
{
if (entry is Ast.MessageTermBase mt)
{
mt.Comment = lastComment;
if (_withSpans)
{
mt.Span.Start = lastComment.Span.Start;
}
}
else
{
entries.Add(lastComment);
}
// In either case, the stashed comment has been dealt with; clear it.
lastComment = null;
}
// No special logic for other types of entries.
entries.Add(entry);
}
var res = new Ast.Resource(entries);
if (_withSpans)
{
res.AddSpan(Position.Start, ps.GetPosition());
}
return(res);
}
T SpanWrapper <T>(FtlParserStream ps, Func <T> wrappedFn) where T : Ast.SyntaxNode
{
if (!_withSpans)
{
return(wrappedFn());
}
var start = ps.GetPosition();
var node = wrappedFn();
// Don't re-add the span if the node already has it. This may happen when
// one decorated function calls another decorated function.
if (node.Span != null)
{
return(node);
}
var end = ps.GetPosition();
node.AddSpan(start, end);
return(node);
}