1 // Copyright 2016 The Rust Project Developers. See the COPYRIGHT
2 // file at the top-level directory of this distribution and at
3 // http://rust-lang.org/COPYRIGHT.
5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8 // option. This file may not be copied, modified, or distributed
9 // except according to those terms.
11 //! This module contains utilities that work with the `SourceMap` from `libsyntax`/`syntex_syntax`.
12 //! This includes extension traits and methods for looking up spans and line ranges for AST nodes.
14 use config::file_lines::LineRange;
15 use syntax::source_map::{BytePos, SourceMap, Span};
16 use visitor::SnippetProvider;
18 use comment::FindUncommented;
21 fn span_after(&self, original: Span, needle: &str) -> BytePos;
22 fn span_after_last(&self, original: Span, needle: &str) -> BytePos;
23 fn span_before(&self, original: Span, needle: &str) -> BytePos;
24 fn opt_span_after(&self, original: Span, needle: &str) -> Option<BytePos>;
25 fn opt_span_before(&self, original: Span, needle: &str) -> Option<BytePos>;
28 pub trait LineRangeUtils {
29 /// Returns the `LineRange` that corresponds to `span` in `self`.
33 /// Panics if `span` crosses a file boundary, which shouldn't happen.
34 fn lookup_line_range(&self, span: Span) -> LineRange;
37 impl<'a> SpanUtils for SnippetProvider<'a> {
38 fn span_after(&self, original: Span, needle: &str) -> BytePos {
39 self.opt_span_after(original, needle).expect("bad span")
42 fn span_after_last(&self, original: Span, needle: &str) -> BytePos {
43 let snippet = self.span_to_snippet(original).unwrap();
46 while let Some(additional_offset) = snippet[offset..].find_uncommented(needle) {
47 offset += additional_offset + needle.len();
50 original.lo() + BytePos(offset as u32)
53 fn span_before(&self, original: Span, needle: &str) -> BytePos {
54 self.opt_span_before(original, needle).expect(&format!(
57 self.span_to_snippet(original).unwrap()
61 fn opt_span_after(&self, original: Span, needle: &str) -> Option<BytePos> {
62 self.opt_span_before(original, needle)
63 .map(|bytepos| bytepos + BytePos(needle.len() as u32))
66 fn opt_span_before(&self, original: Span, needle: &str) -> Option<BytePos> {
67 let snippet = self.span_to_snippet(original)?;
68 let offset = snippet.find_uncommented(needle)?;
70 Some(original.lo() + BytePos(offset as u32))
74 impl LineRangeUtils for SourceMap {
75 fn lookup_line_range(&self, span: Span) -> LineRange {
76 let lo = self.lookup_line(span.lo()).unwrap();
77 let hi = self.lookup_line(span.hi()).unwrap();
80 lo.fm.name, hi.fm.name,
81 "span crossed file boundary: lo: {:?}, hi: {:?}",
85 // Line numbers start at 1