1 // Copyright 2012-2013 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 //! The source positions and related helper functions
15 //! This API is completely unstable and subject to change.
17 #![crate_name = "syntax_pos"]
18 #![crate_type = "dylib"]
19 #![crate_type = "rlib"]
20 #![doc(html_logo_url = "https://www.rust-lang.org/logos/rust-logo-128x128-blk-v2.png",
21 html_favicon_url = "https://doc.rust-lang.org/favicon.ico",
22 html_root_url = "https://doc.rust-lang.org/nightly/")]
26 #![feature(custom_attribute)]
27 #![feature(i128_type)]
28 #![feature(optin_builtin_traits)]
29 #![allow(unused_attributes)]
30 #![feature(specialization)]
33 use std::cell::{Cell, RefCell};
36 use std::hash::Hasher;
37 use std::ops::{Add, Sub};
40 use rustc_data_structures::stable_hasher::StableHasher;
42 extern crate rustc_data_structures;
44 use serialize::{Encodable, Decodable, Encoder, Decoder};
46 extern crate serialize;
47 extern crate serialize as rustc_serialize; // used by deriving
50 pub use hygiene::{SyntaxContext, ExpnInfo, ExpnFormat, NameAndSpan};
54 pub type FileName = String;
56 /// Spans represent a region of code, used for error reporting. Positions in spans
57 /// are *absolute* positions from the beginning of the codemap, not positions
58 /// relative to FileMaps. Methods on the CodeMap can be used to relate spans back
59 /// to the original source.
60 /// You must be careful if the span crosses more than one file - you will not be
61 /// able to use many of the functions on spans in codemap and you cannot assume
62 /// that the length of the span = hi - lo; there may be space in the BytePos
63 /// range between files.
64 #[derive(Clone, Copy, Hash, PartialEq, Eq, Ord, PartialOrd)]
68 /// Information about where the macro came from, if this piece of
69 /// code was created by a macro expansion.
70 pub ctxt: SyntaxContext,
73 /// A collection of spans. Spans have two orthogonal attributes:
75 /// - they can be *primary spans*. In this case they are the locus of
76 /// the error, and would be rendered with `^^^`.
77 /// - they can have a *label*. In this case, the label is written next
78 /// to the mark in the snippet when we render.
79 #[derive(Clone, Debug, Hash, PartialEq, Eq, RustcEncodable, RustcDecodable)]
80 pub struct MultiSpan {
81 primary_spans: Vec<Span>,
82 span_labels: Vec<(Span, String)>,
86 /// Returns a new span representing just the end-point of this span
87 pub fn end_point(self) -> Span {
88 let lo = cmp::max(self.hi.0 - 1, self.lo.0);
89 Span { lo: BytePos(lo), ..self }
92 /// Returns a new span representing the next character after the end-point of this span
93 pub fn next_point(self) -> Span {
94 let lo = cmp::max(self.hi.0, self.lo.0 + 1);
95 Span { lo: BytePos(lo), hi: BytePos(lo), ..self }
98 /// Returns `self` if `self` is not the dummy span, and `other` otherwise.
99 pub fn substitute_dummy(self, other: Span) -> Span {
100 if self.source_equal(&DUMMY_SP) { other } else { self }
103 /// Return true if `self` fully encloses `other`.
104 pub fn contains(self, other: Span) -> bool {
105 self.lo <= other.lo && other.hi <= self.hi
108 /// Return true if the spans are equal with regards to the source text.
110 /// Use this instead of `==` when either span could be generated code,
111 /// and you only care that they point to the same bytes of source text.
112 pub fn source_equal(&self, other: &Span) -> bool {
113 self.lo == other.lo && self.hi == other.hi
116 /// Returns `Some(span)`, where the start is trimmed by the end of `other`
117 pub fn trim_start(self, other: Span) -> Option<Span> {
118 if self.hi > other.hi {
119 Some(Span { lo: cmp::max(self.lo, other.hi), .. self })
125 /// Return the source span - this is either the supplied span, or the span for
126 /// the macro callsite that expanded to it.
127 pub fn source_callsite(self) -> Span {
128 self.ctxt.outer().expn_info().map(|info| info.call_site.source_callsite()).unwrap_or(self)
131 /// Return the source callee.
133 /// Returns None if the supplied span has no expansion trace,
134 /// else returns the NameAndSpan for the macro definition
135 /// corresponding to the source callsite.
136 pub fn source_callee(self) -> Option<NameAndSpan> {
137 fn source_callee(info: ExpnInfo) -> NameAndSpan {
138 match info.call_site.ctxt.outer().expn_info() {
139 Some(info) => source_callee(info),
143 self.ctxt.outer().expn_info().map(source_callee)
146 /// Check if a span is "internal" to a macro in which #[unstable]
147 /// items can be used (that is, a macro marked with
148 /// `#[allow_internal_unstable]`).
149 pub fn allows_unstable(&self) -> bool {
150 match self.ctxt.outer().expn_info() {
151 Some(info) => info.callee.allow_internal_unstable,
156 pub fn macro_backtrace(mut self) -> Vec<MacroBacktrace> {
157 let mut prev_span = DUMMY_SP;
158 let mut result = vec![];
160 let info = match self.ctxt.outer().expn_info() {
165 let (pre, post) = match info.callee.format {
166 ExpnFormat::MacroAttribute(..) => ("#[", "]"),
167 ExpnFormat::MacroBang(..) => ("", "!"),
168 ExpnFormat::CompilerDesugaring(..) => ("desugaring of `", "`"),
170 let macro_decl_name = format!("{}{}{}", pre, info.callee.name(), post);
171 let def_site_span = info.callee.span;
173 // Don't print recursive invocations
174 if !info.call_site.source_equal(&prev_span) {
175 result.push(MacroBacktrace {
176 call_site: info.call_site,
177 macro_decl_name: macro_decl_name,
178 def_site_span: def_site_span,
183 self = info.call_site;
188 /// Return a `Span` that would enclose both `self` and `end`.
189 pub fn to(self, end: Span) -> Span {
191 lo: cmp::min(self.lo, end.lo),
192 hi: cmp::max(self.hi, end.hi),
193 // FIXME(jseyfried): self.ctxt should always equal end.ctxt here (c.f. issue #23480)
194 ctxt: if self.ctxt == SyntaxContext::empty() {
202 /// Return a `Span` between the end of `self` to the beginning of `end`.
203 pub fn between(self, end: Span) -> Span {
207 ctxt: if end.ctxt == SyntaxContext::empty() {
215 /// Return a `Span` between the beginning of `self` to the beginning of `end`.
216 pub fn until(self, end: Span) -> Span {
220 ctxt: if end.ctxt == SyntaxContext::empty() {
229 #[derive(Clone, Debug)]
230 pub struct SpanLabel {
231 /// The span we are going to include in the final snippet.
234 /// Is this a primary span? This is the "locus" of the message,
235 /// and is indicated with a `^^^^` underline, versus `----`.
236 pub is_primary: bool,
238 /// What label should we attach to this span (if any)?
239 pub label: Option<String>,
242 impl Default for Span {
243 fn default() -> Self {
248 impl serialize::UseSpecializedEncodable for Span {
249 fn default_encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
250 s.emit_struct("Span", 2, |s| {
251 s.emit_struct_field("lo", 0, |s| {
255 s.emit_struct_field("hi", 1, |s| {
262 impl serialize::UseSpecializedDecodable for Span {
263 fn default_decode<D: Decoder>(d: &mut D) -> Result<Span, D::Error> {
264 d.read_struct("Span", 2, |d| {
265 let lo = d.read_struct_field("lo", 0, Decodable::decode)?;
266 let hi = d.read_struct_field("hi", 1, Decodable::decode)?;
267 Ok(Span { lo: lo, hi: hi, ctxt: NO_EXPANSION })
272 fn default_span_debug(span: Span, f: &mut fmt::Formatter) -> fmt::Result {
273 write!(f, "Span {{ lo: {:?}, hi: {:?}, ctxt: {:?} }}",
274 span.lo, span.hi, span.ctxt)
277 impl fmt::Debug for Span {
278 fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
279 SPAN_DEBUG.with(|span_debug| span_debug.get()(*self, f))
283 pub const DUMMY_SP: Span = Span { lo: BytePos(0), hi: BytePos(0), ctxt: NO_EXPANSION };
286 pub fn new() -> MultiSpan {
288 primary_spans: vec![],
293 pub fn from_span(primary_span: Span) -> MultiSpan {
295 primary_spans: vec![primary_span],
300 pub fn from_spans(vec: Vec<Span>) -> MultiSpan {
307 pub fn push_span_label(&mut self, span: Span, label: String) {
308 self.span_labels.push((span, label));
311 /// Selects the first primary span (if any)
312 pub fn primary_span(&self) -> Option<Span> {
313 self.primary_spans.first().cloned()
316 /// Returns all primary spans.
317 pub fn primary_spans(&self) -> &[Span] {
321 /// Replaces all occurrences of one Span with another. Used to move Spans in areas that don't
322 /// display well (like std macros). Returns true if replacements occurred.
323 pub fn replace(&mut self, before: Span, after: Span) -> bool {
324 let mut replacements_occurred = false;
325 for primary_span in &mut self.primary_spans {
326 if *primary_span == before {
327 *primary_span = after;
328 replacements_occurred = true;
331 for span_label in &mut self.span_labels {
332 if span_label.0 == before {
333 span_label.0 = after;
334 replacements_occurred = true;
337 replacements_occurred
340 /// Returns the strings to highlight. We always ensure that there
341 /// is an entry for each of the primary spans -- for each primary
342 /// span P, if there is at least one label with span P, we return
343 /// those labels (marked as primary). But otherwise we return
344 /// `SpanLabel` instances with empty labels.
345 pub fn span_labels(&self) -> Vec<SpanLabel> {
346 let is_primary = |span| self.primary_spans.contains(&span);
347 let mut span_labels = vec![];
349 for &(span, ref label) in &self.span_labels {
350 span_labels.push(SpanLabel {
352 is_primary: is_primary(span),
353 label: Some(label.clone())
357 for &span in &self.primary_spans {
358 if !span_labels.iter().any(|sl| sl.span == span) {
359 span_labels.push(SpanLabel {
371 impl From<Span> for MultiSpan {
372 fn from(span: Span) -> MultiSpan {
373 MultiSpan::from_span(span)
377 pub const NO_EXPANSION: SyntaxContext = SyntaxContext::empty();
379 /// Identifies an offset of a multi-byte character in a FileMap
380 #[derive(Copy, Clone, RustcEncodable, RustcDecodable, Eq, PartialEq)]
381 pub struct MultiByteChar {
382 /// The absolute offset of the character in the CodeMap
384 /// The number of bytes, >=2
388 /// The state of the lazy external source loading mechanism of a FileMap.
389 #[derive(PartialEq, Eq, Clone)]
390 pub enum ExternalSource {
391 /// The external source has been loaded already.
393 /// No attempt has been made to load the external source.
395 /// A failed attempt has been made to load the external source.
397 /// No external source has to be loaded, since the FileMap represents a local crate.
401 impl ExternalSource {
402 pub fn is_absent(&self) -> bool {
404 ExternalSource::Present(_) => false,
409 pub fn get_source(&self) -> Option<&str> {
411 ExternalSource::Present(ref src) => Some(src),
417 /// A single source in the CodeMap.
420 /// The name of the file that the source came from, source that doesn't
421 /// originate from files has names between angle brackets by convention,
424 /// True if the `name` field above has been modified by -Zremap-path-prefix
425 pub name_was_remapped: bool,
426 /// Indicates which crate this FileMap was imported from.
427 pub crate_of_origin: u32,
428 /// The complete source code
429 pub src: Option<Rc<String>>,
430 /// The source code's hash
432 /// The external source code (used for external crates, which will have a `None`
433 /// value as `self.src`.
434 pub external_src: RefCell<ExternalSource>,
435 /// The start position of this source in the CodeMap
436 pub start_pos: BytePos,
437 /// The end position of this source in the CodeMap
438 pub end_pos: BytePos,
439 /// Locations of lines beginnings in the source code
440 pub lines: RefCell<Vec<BytePos>>,
441 /// Locations of multi-byte characters in the source code
442 pub multibyte_chars: RefCell<Vec<MultiByteChar>>,
445 impl Encodable for FileMap {
446 fn encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
447 s.emit_struct("FileMap", 7, |s| {
448 s.emit_struct_field("name", 0, |s| self.name.encode(s))?;
449 s.emit_struct_field("name_was_remapped", 1, |s| self.name_was_remapped.encode(s))?;
450 s.emit_struct_field("src_hash", 6, |s| self.src_hash.encode(s))?;
451 s.emit_struct_field("start_pos", 2, |s| self.start_pos.encode(s))?;
452 s.emit_struct_field("end_pos", 3, |s| self.end_pos.encode(s))?;
453 s.emit_struct_field("lines", 4, |s| {
454 let lines = self.lines.borrow();
456 s.emit_u32(lines.len() as u32)?;
458 if !lines.is_empty() {
459 // In order to preserve some space, we exploit the fact that
460 // the lines list is sorted and individual lines are
461 // probably not that long. Because of that we can store lines
462 // as a difference list, using as little space as possible
463 // for the differences.
464 let max_line_length = if lines.len() == 1 {
468 .map(|w| w[1] - w[0])
469 .map(|bp| bp.to_usize())
474 let bytes_per_diff: u8 = match max_line_length {
476 0x100 ... 0xFFFF => 2,
480 // Encode the number of bytes used per diff.
481 bytes_per_diff.encode(s)?;
483 // Encode the first element.
486 let diff_iter = (&lines[..]).windows(2)
487 .map(|w| (w[1] - w[0]));
489 match bytes_per_diff {
490 1 => for diff in diff_iter { (diff.0 as u8).encode(s)? },
491 2 => for diff in diff_iter { (diff.0 as u16).encode(s)? },
492 4 => for diff in diff_iter { diff.0.encode(s)? },
499 s.emit_struct_field("multibyte_chars", 5, |s| {
500 (*self.multibyte_chars.borrow()).encode(s)
506 impl Decodable for FileMap {
507 fn decode<D: Decoder>(d: &mut D) -> Result<FileMap, D::Error> {
509 d.read_struct("FileMap", 6, |d| {
510 let name: String = d.read_struct_field("name", 0, |d| Decodable::decode(d))?;
511 let name_was_remapped: bool =
512 d.read_struct_field("name_was_remapped", 1, |d| Decodable::decode(d))?;
514 d.read_struct_field("src_hash", 6, |d| Decodable::decode(d))?;
515 let start_pos: BytePos =
516 d.read_struct_field("start_pos", 2, |d| Decodable::decode(d))?;
517 let end_pos: BytePos = d.read_struct_field("end_pos", 3, |d| Decodable::decode(d))?;
518 let lines: Vec<BytePos> = d.read_struct_field("lines", 4, |d| {
519 let num_lines: u32 = Decodable::decode(d)?;
520 let mut lines = Vec::with_capacity(num_lines as usize);
523 // Read the number of bytes used per diff.
524 let bytes_per_diff: u8 = Decodable::decode(d)?;
526 // Read the first element.
527 let mut line_start: BytePos = Decodable::decode(d)?;
528 lines.push(line_start);
530 for _ in 1..num_lines {
531 let diff = match bytes_per_diff {
532 1 => d.read_u8()? as u32,
533 2 => d.read_u16()? as u32,
538 line_start = line_start + BytePos(diff);
540 lines.push(line_start);
546 let multibyte_chars: Vec<MultiByteChar> =
547 d.read_struct_field("multibyte_chars", 5, |d| Decodable::decode(d))?;
550 name_was_remapped: name_was_remapped,
551 // `crate_of_origin` has to be set by the importer.
552 // This value matches up with rustc::hir::def_id::INVALID_CRATE.
553 // That constant is not available here unfortunately :(
554 crate_of_origin: ::std::u32::MAX - 1,
555 start_pos: start_pos,
559 external_src: RefCell::new(ExternalSource::AbsentOk),
560 lines: RefCell::new(lines),
561 multibyte_chars: RefCell::new(multibyte_chars)
567 impl fmt::Debug for FileMap {
568 fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
569 write!(fmt, "FileMap({})", self.name)
574 pub fn new(name: FileName,
575 name_was_remapped: bool,
577 start_pos: BytePos) -> FileMap {
578 remove_bom(&mut src);
580 let mut hasher: StableHasher<u128> = StableHasher::new();
581 hasher.write(src.as_bytes());
582 let src_hash = hasher.finish();
584 let end_pos = start_pos.to_usize() + src.len();
588 name_was_remapped: name_was_remapped,
590 src: Some(Rc::new(src)),
592 external_src: RefCell::new(ExternalSource::Unneeded),
593 start_pos: start_pos,
594 end_pos: Pos::from_usize(end_pos),
595 lines: RefCell::new(Vec::new()),
596 multibyte_chars: RefCell::new(Vec::new()),
600 /// EFFECT: register a start-of-line offset in the
601 /// table of line-beginnings.
602 /// UNCHECKED INVARIANT: these offsets must be added in the right
603 /// order and must be in the right places; there is shared knowledge
604 /// about what ends a line between this file and parse.rs
605 /// WARNING: pos param here is the offset relative to start of CodeMap,
606 /// and CodeMap will append a newline when adding a filemap without a newline at the end,
607 /// so the safe way to call this is with value calculated as
608 /// filemap.start_pos + newline_offset_relative_to_the_start_of_filemap.
609 pub fn next_line(&self, pos: BytePos) {
610 // the new charpos must be > the last one (or it's the first one).
611 let mut lines = self.lines.borrow_mut();
612 let line_len = lines.len();
613 assert!(line_len == 0 || ((*lines)[line_len - 1] < pos));
617 /// Add externally loaded source.
618 /// If the hash of the input doesn't match or no input is supplied via None,
619 /// it is interpreted as an error and the corresponding enum variant is set.
620 /// The return value signifies whether some kind of source is present.
621 pub fn add_external_src<F>(&self, get_src: F) -> bool
622 where F: FnOnce() -> Option<String>
624 if *self.external_src.borrow() == ExternalSource::AbsentOk {
626 let mut external_src = self.external_src.borrow_mut();
627 if let Some(src) = src {
628 let mut hasher: StableHasher<u128> = StableHasher::new();
629 hasher.write(src.as_bytes());
631 if hasher.finish() == self.src_hash {
632 *external_src = ExternalSource::Present(src);
636 *external_src = ExternalSource::AbsentErr;
641 self.src.is_some() || self.external_src.borrow().get_source().is_some()
645 /// Get a line from the list of pre-computed line-beginnings.
646 /// The line number here is 0-based.
647 pub fn get_line(&self, line_number: usize) -> Option<Cow<str>> {
648 fn get_until_newline(src: &str, begin: usize) -> &str {
649 // We can't use `lines.get(line_number+1)` because we might
650 // be parsing when we call this function and thus the current
651 // line is the last one we have line info for.
652 let slice = &src[begin..];
653 match slice.find('\n') {
654 Some(e) => &slice[..e],
659 let lines = self.lines.borrow();
660 let line = if let Some(line) = lines.get(line_number) {
665 let begin: BytePos = *line - self.start_pos;
666 let begin = begin.to_usize();
668 if let Some(ref src) = self.src {
669 Some(Cow::from(get_until_newline(src, begin)))
670 } else if let Some(src) = self.external_src.borrow().get_source() {
671 Some(Cow::Owned(String::from(get_until_newline(src, begin))))
677 pub fn record_multibyte_char(&self, pos: BytePos, bytes: usize) {
678 assert!(bytes >=2 && bytes <= 4);
679 let mbc = MultiByteChar {
683 self.multibyte_chars.borrow_mut().push(mbc);
686 pub fn is_real_file(&self) -> bool {
687 !(self.name.starts_with("<") &&
688 self.name.ends_with(">"))
691 pub fn is_imported(&self) -> bool {
695 pub fn byte_length(&self) -> u32 {
696 self.end_pos.0 - self.start_pos.0
698 pub fn count_lines(&self) -> usize {
699 self.lines.borrow().len()
702 /// Find the line containing the given position. The return value is the
703 /// index into the `lines` array of this FileMap, not the 1-based line
704 /// number. If the filemap is empty or the position is located before the
705 /// first line, None is returned.
706 pub fn lookup_line(&self, pos: BytePos) -> Option<usize> {
707 let lines = self.lines.borrow();
708 if lines.len() == 0 {
712 let line_index = lookup_line(&lines[..], pos);
713 assert!(line_index < lines.len() as isize);
715 Some(line_index as usize)
721 pub fn line_bounds(&self, line_index: usize) -> (BytePos, BytePos) {
722 if self.start_pos == self.end_pos {
723 return (self.start_pos, self.end_pos);
726 let lines = self.lines.borrow();
727 assert!(line_index < lines.len());
728 if line_index == (lines.len() - 1) {
729 (lines[line_index], self.end_pos)
731 (lines[line_index], lines[line_index + 1])
736 /// Remove utf-8 BOM if any.
737 fn remove_bom(src: &mut String) {
738 if src.starts_with("\u{feff}") {
743 // _____________________________________________________________________________
744 // Pos, BytePos, CharPos
748 fn from_usize(n: usize) -> Self;
749 fn to_usize(&self) -> usize;
752 /// A byte offset. Keep this small (currently 32-bits), as AST contains
754 #[derive(Clone, Copy, PartialEq, Eq, Hash, PartialOrd, Ord, Debug)]
755 pub struct BytePos(pub u32);
757 /// A character offset. Because of multibyte utf8 characters, a byte offset
758 /// is not equivalent to a character offset. The CodeMap will convert BytePos
759 /// values to CharPos values as necessary.
760 #[derive(Copy, Clone, PartialEq, Eq, Hash, PartialOrd, Ord, Debug)]
761 pub struct CharPos(pub usize);
763 // FIXME: Lots of boilerplate in these impls, but so far my attempts to fix
764 // have been unsuccessful
766 impl Pos for BytePos {
767 fn from_usize(n: usize) -> BytePos { BytePos(n as u32) }
768 fn to_usize(&self) -> usize { let BytePos(n) = *self; n as usize }
771 impl Add for BytePos {
772 type Output = BytePos;
774 fn add(self, rhs: BytePos) -> BytePos {
775 BytePos((self.to_usize() + rhs.to_usize()) as u32)
779 impl Sub for BytePos {
780 type Output = BytePos;
782 fn sub(self, rhs: BytePos) -> BytePos {
783 BytePos((self.to_usize() - rhs.to_usize()) as u32)
787 impl Encodable for BytePos {
788 fn encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
793 impl Decodable for BytePos {
794 fn decode<D: Decoder>(d: &mut D) -> Result<BytePos, D::Error> {
795 Ok(BytePos(d.read_u32()?))
799 impl Pos for CharPos {
800 fn from_usize(n: usize) -> CharPos { CharPos(n) }
801 fn to_usize(&self) -> usize { let CharPos(n) = *self; n }
804 impl Add for CharPos {
805 type Output = CharPos;
807 fn add(self, rhs: CharPos) -> CharPos {
808 CharPos(self.to_usize() + rhs.to_usize())
812 impl Sub for CharPos {
813 type Output = CharPos;
815 fn sub(self, rhs: CharPos) -> CharPos {
816 CharPos(self.to_usize() - rhs.to_usize())
820 // _____________________________________________________________________________
821 // Loc, LocWithOpt, FileMapAndLine, FileMapAndBytePos
824 /// A source code location used for error reporting
825 #[derive(Debug, Clone)]
827 /// Information about the original source
828 pub file: Rc<FileMap>,
829 /// The (1-based) line number
831 /// The (0-based) column offset
835 /// A source code location used as the result of lookup_char_pos_adj
836 // Actually, *none* of the clients use the filename *or* file field;
837 // perhaps they should just be removed.
839 pub struct LocWithOpt {
840 pub filename: FileName,
843 pub file: Option<Rc<FileMap>>,
846 // used to be structural records. Better names, anyone?
848 pub struct FileMapAndLine { pub fm: Rc<FileMap>, pub line: usize }
850 pub struct FileMapAndBytePos { pub fm: Rc<FileMap>, pub pos: BytePos }
852 #[derive(Copy, Clone, Debug, PartialEq, Eq)]
853 pub struct LineInfo {
854 /// Index of line, starting from 0.
855 pub line_index: usize,
857 /// Column in line where span begins, starting from 0.
858 pub start_col: CharPos,
860 /// Column in line where span ends, starting from 0, exclusive.
861 pub end_col: CharPos,
864 pub struct FileLines {
865 pub file: Rc<FileMap>,
866 pub lines: Vec<LineInfo>
869 thread_local!(pub static SPAN_DEBUG: Cell<fn(Span, &mut fmt::Formatter) -> fmt::Result> =
870 Cell::new(default_span_debug));
873 pub struct MacroBacktrace {
874 /// span where macro was applied to generate this code
877 /// name of macro that was applied (e.g., "foo!" or "#[derive(Eq)]")
878 pub macro_decl_name: String,
880 /// span where macro was defined (if known)
881 pub def_site_span: Option<Span>,
884 // _____________________________________________________________________________
885 // SpanLinesError, SpanSnippetError, DistinctSources, MalformedCodemapPositions
888 pub type FileLinesResult = Result<FileLines, SpanLinesError>;
890 #[derive(Clone, PartialEq, Eq, Debug)]
891 pub enum SpanLinesError {
893 DistinctSources(DistinctSources),
896 #[derive(Clone, PartialEq, Eq, Debug)]
897 pub enum SpanSnippetError {
899 DistinctSources(DistinctSources),
900 MalformedForCodemap(MalformedCodemapPositions),
901 SourceNotAvailable { filename: String }
904 #[derive(Clone, PartialEq, Eq, Debug)]
905 pub struct DistinctSources {
906 pub begin: (String, BytePos),
907 pub end: (String, BytePos)
910 #[derive(Clone, PartialEq, Eq, Debug)]
911 pub struct MalformedCodemapPositions {
913 pub source_len: usize,
914 pub begin_pos: BytePos,
918 // Given a slice of line start positions and a position, returns the index of
919 // the line the position is on. Returns -1 if the position is located before
921 fn lookup_line(lines: &[BytePos], pos: BytePos) -> isize {
922 match lines.binary_search(&pos) {
923 Ok(line) => line as isize,
924 Err(line) => line as isize - 1
930 use super::{lookup_line, BytePos};
933 fn test_lookup_line() {
935 let lines = &[BytePos(3), BytePos(17), BytePos(28)];
937 assert_eq!(lookup_line(lines, BytePos(0)), -1);
938 assert_eq!(lookup_line(lines, BytePos(3)), 0);
939 assert_eq!(lookup_line(lines, BytePos(4)), 0);
941 assert_eq!(lookup_line(lines, BytePos(16)), 0);
942 assert_eq!(lookup_line(lines, BytePos(17)), 1);
943 assert_eq!(lookup_line(lines, BytePos(18)), 1);
945 assert_eq!(lookup_line(lines, BytePos(28)), 2);
946 assert_eq!(lookup_line(lines, BytePos(29)), 2);