1 use crate::generated_code;
2 use rustc_data_structures::sync::Lrc;
3 use rustc_lexer::{tokenize, TokenKind};
4 use rustc_session::Session;
8 pub struct SpanUtils<'a> {
12 impl<'a> SpanUtils<'a> {
13 pub fn new(sess: &'a Session) -> SpanUtils<'a> {
17 pub fn make_filename_string(&self, file: &SourceFile) -> String {
19 FileName::Real(RealFileName::LocalPath(path)) => {
20 if path.is_absolute() {
24 .map_prefix(path.into())
31 .remapped_path_if_available()
37 filename => filename.prefer_remapped().to_string(),
41 pub fn snippet(&self, span: Span) -> String {
42 match self.sess.source_map().span_to_snippet(span) {
44 Err(_) => String::new(),
48 /// Finds the span of `*` token withing the larger `span`.
49 pub fn sub_span_of_star(&self, mut span: Span) -> Option<Span> {
50 let begin = self.sess.source_map().lookup_byte_offset(span.lo());
51 let end = self.sess.source_map().lookup_byte_offset(span.hi());
52 // Make the range zero-length if the span is invalid.
53 if begin.sf.start_pos != end.sf.start_pos {
54 span = span.shrink_to_lo();
57 let sf = Lrc::clone(&begin.sf);
59 self.sess.source_map().ensure_source_file_source_present(Lrc::clone(&sf));
61 sf.src.clone().or_else(|| sf.external_src.borrow().get_source().map(Lrc::clone))?;
62 let to_index = |pos: BytePos| -> usize { (pos - sf.start_pos).0 as usize };
63 let text = &src[to_index(span.lo())..to_index(span.hi())];
72 .find(|(_pos, token)| token.kind == TokenKind::Star)?
75 let lo = span.lo() + BytePos(start_pos as u32);
76 let hi = lo + BytePos(1);
77 Some(span.with_lo(lo).with_hi(hi))
80 /// Return true if the span is generated code, and
81 /// it is not a subspan of the root callsite.
83 /// Used to filter out spans of minimal value,
84 /// such as references to macro internal variables.
85 pub fn filter_generated(&self, span: Span) -> bool {
86 if generated_code(span) {
90 //If the span comes from a fake source_file, filter it.
91 !self.sess.source_map().lookup_char_pos(span.lo()).file.is_real_file()
96 ($util: expr, $parent: expr) => {
97 if $util.filter_generated($parent) {