1 // Copyright 2012-2015 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 #![crate_name = "rustc_errors"]
12 #![unstable(feature = "rustc_private", issue = "27812")]
13 #![crate_type = "dylib"]
14 #![crate_type = "rlib"]
15 #![doc(html_logo_url = "https://www.rust-lang.org/logos/rust-logo-128x128-blk-v2.png",
16 html_favicon_url = "https://doc.rust-lang.org/favicon.ico",
17 html_root_url = "https://doc.rust-lang.org/nightly/")]
20 #![feature(custom_attribute)]
21 #![allow(unused_attributes)]
22 #![feature(rustc_private)]
23 #![feature(staged_api)]
24 #![feature(range_contains)]
29 extern crate serialize as rustc_serialize;
30 extern crate syntax_pos;
32 pub use emitter::ColorConfig;
36 use emitter::{Emitter, EmitterWriter};
38 use std::cell::{RefCell, Cell};
39 use std::{error, fmt};
43 pub mod diagnostic_builder;
47 pub mod styled_buffer;
50 use syntax_pos::{BytePos, Loc, FileLinesResult, FileName, MultiSpan, Span, NO_EXPANSION};
52 #[derive(Clone, Debug, PartialEq, RustcEncodable, RustcDecodable)]
54 /// A FullSpan renders with both with an initial line for the
55 /// message, prefixed by file:linenum, followed by a summary of
56 /// the source code covered by the span.
59 /// A suggestion renders with both with an initial line for the
60 /// message, prefixed by file:linenum, followed by a summary
61 /// of hypothetical source code, where each `String` is spliced
62 /// into the lines in place of the code covered by each span.
63 Suggestion(CodeSuggestion),
66 #[derive(Clone, Debug, PartialEq, RustcEncodable, RustcDecodable)]
67 pub struct CodeSuggestion {
69 pub substitutes: Vec<String>,
72 pub trait CodeMapper {
73 fn lookup_char_pos(&self, pos: BytePos) -> Loc;
74 fn span_to_lines(&self, sp: Span) -> FileLinesResult;
75 fn span_to_string(&self, sp: Span) -> String;
76 fn span_to_filename(&self, sp: Span) -> FileName;
77 fn merge_spans(&self, sp_lhs: Span, sp_rhs: Span) -> Option<Span>;
81 /// Returns the assembled code suggestion.
82 pub fn splice_lines(&self, cm: &CodeMapper) -> String {
83 use syntax_pos::{CharPos, Loc, Pos};
85 fn push_trailing(buf: &mut String,
86 line_opt: Option<&str>,
88 hi_opt: Option<&Loc>) {
89 let (lo, hi_opt) = (lo.col.to_usize(), hi_opt.map(|hi| hi.col.to_usize()));
90 if let Some(line) = line_opt {
91 if let Some(lo) = line.char_indices().map(|(i, _)| i).nth(lo) {
92 let hi_opt = hi_opt.and_then(|hi| line.char_indices().map(|(i, _)| i).nth(hi));
93 buf.push_str(match hi_opt {
94 Some(hi) => &line[lo..hi],
98 if let None = hi_opt {
104 let mut primary_spans = self.msp.primary_spans().to_owned();
106 assert_eq!(primary_spans.len(), self.substitutes.len());
107 if primary_spans.is_empty() {
111 // Assumption: all spans are in the same file, and all spans
112 // are disjoint. Sort in ascending order.
113 primary_spans.sort_by_key(|sp| sp.lo);
115 // Find the bounding span.
116 let lo = primary_spans.iter().map(|sp| sp.lo).min().unwrap();
117 let hi = primary_spans.iter().map(|sp| sp.hi).min().unwrap();
118 let bounding_span = Span {
123 let lines = cm.span_to_lines(bounding_span).unwrap();
124 assert!(!lines.lines.is_empty());
126 // To build up the result, we do this for each span:
127 // - push the line segment trailing the previous span
128 // (at the beginning a "phantom" span pointing at the start of the line)
129 // - push lines between the previous and current span (if any)
130 // - if the previous and current span are not on the same line
131 // push the line segment leading up to the current span
132 // - splice in the span substitution
134 // Finally push the trailing line segment of the last span
135 let fm = &lines.file;
136 let mut prev_hi = cm.lookup_char_pos(bounding_span.lo);
137 prev_hi.col = CharPos::from_usize(0);
139 let mut prev_line = fm.get_line(lines.lines[0].line_index);
140 let mut buf = String::new();
142 for (sp, substitute) in primary_spans.iter().zip(self.substitutes.iter()) {
143 let cur_lo = cm.lookup_char_pos(sp.lo);
144 if prev_hi.line == cur_lo.line {
145 push_trailing(&mut buf, prev_line, &prev_hi, Some(&cur_lo));
147 push_trailing(&mut buf, prev_line, &prev_hi, None);
148 // push lines between the previous and current span (if any)
149 for idx in prev_hi.line..(cur_lo.line - 1) {
150 if let Some(line) = fm.get_line(idx) {
155 if let Some(cur_line) = fm.get_line(cur_lo.line - 1) {
156 buf.push_str(&cur_line[..cur_lo.col.to_usize()]);
159 buf.push_str(substitute);
160 prev_hi = cm.lookup_char_pos(sp.hi);
161 prev_line = fm.get_line(prev_hi.line - 1);
163 push_trailing(&mut buf, prev_line, &prev_hi, None);
164 // remove trailing newline
170 /// Used as a return value to signify a fatal error occurred. (It is also
171 /// used as the argument to panic at the moment, but that will eventually
173 #[derive(Copy, Clone, Debug)]
175 pub struct FatalError;
177 impl fmt::Display for FatalError {
178 fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
179 write!(f, "parser fatal error")
183 impl error::Error for FatalError {
184 fn description(&self) -> &str {
185 "The parser has encountered a fatal error"
189 /// Signifies that the compiler died with an explicit call to `.bug`
190 /// or `.span_bug` rather than a failed assertion, etc.
191 #[derive(Copy, Clone, Debug)]
192 pub struct ExplicitBug;
194 impl fmt::Display for ExplicitBug {
195 fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
196 write!(f, "parser internal bug")
200 impl error::Error for ExplicitBug {
201 fn description(&self) -> &str {
202 "The parser has encountered an internal bug"
206 pub use diagnostic::{Diagnostic, SubDiagnostic};
207 pub use diagnostic_builder::DiagnosticBuilder;
209 /// A handler deals with errors; certain errors
210 /// (fatal, bug, unimpl) may cause immediate exit,
211 /// others log errors for later reporting.
213 err_count: Cell<usize>,
214 emitter: RefCell<Box<Emitter>>,
215 pub can_emit_warnings: bool,
216 treat_err_as_bug: bool,
217 continue_after_error: Cell<bool>,
218 delayed_span_bug: RefCell<Option<(MultiSpan, String)>>,
222 pub fn with_tty_emitter(color_config: ColorConfig,
223 can_emit_warnings: bool,
224 treat_err_as_bug: bool,
225 cm: Option<Rc<CodeMapper>>)
227 let emitter = Box::new(EmitterWriter::stderr(color_config, cm));
228 Handler::with_emitter(can_emit_warnings, treat_err_as_bug, emitter)
231 pub fn with_emitter(can_emit_warnings: bool,
232 treat_err_as_bug: bool,
236 err_count: Cell::new(0),
237 emitter: RefCell::new(e),
238 can_emit_warnings: can_emit_warnings,
239 treat_err_as_bug: treat_err_as_bug,
240 continue_after_error: Cell::new(true),
241 delayed_span_bug: RefCell::new(None),
245 pub fn set_continue_after_error(&self, continue_after_error: bool) {
246 self.continue_after_error.set(continue_after_error);
249 pub fn struct_dummy<'a>(&'a self) -> DiagnosticBuilder<'a> {
250 DiagnosticBuilder::new(self, Level::Cancelled, "")
253 pub fn struct_span_warn<'a, S: Into<MultiSpan>>(&'a self,
256 -> DiagnosticBuilder<'a> {
257 let mut result = DiagnosticBuilder::new(self, Level::Warning, msg);
259 if !self.can_emit_warnings {
264 pub fn struct_span_warn_with_code<'a, S: Into<MultiSpan>>(&'a self,
268 -> DiagnosticBuilder<'a> {
269 let mut result = DiagnosticBuilder::new(self, Level::Warning, msg);
271 result.code(code.to_owned());
272 if !self.can_emit_warnings {
277 pub fn struct_warn<'a>(&'a self, msg: &str) -> DiagnosticBuilder<'a> {
278 let mut result = DiagnosticBuilder::new(self, Level::Warning, msg);
279 if !self.can_emit_warnings {
284 pub fn struct_span_err<'a, S: Into<MultiSpan>>(&'a self,
287 -> DiagnosticBuilder<'a> {
288 let mut result = DiagnosticBuilder::new(self, Level::Error, msg);
292 pub fn struct_span_err_with_code<'a, S: Into<MultiSpan>>(&'a self,
296 -> DiagnosticBuilder<'a> {
297 let mut result = DiagnosticBuilder::new(self, Level::Error, msg);
299 result.code(code.to_owned());
302 pub fn struct_err<'a>(&'a self, msg: &str) -> DiagnosticBuilder<'a> {
303 DiagnosticBuilder::new(self, Level::Error, msg)
305 pub fn struct_span_fatal<'a, S: Into<MultiSpan>>(&'a self,
308 -> DiagnosticBuilder<'a> {
309 let mut result = DiagnosticBuilder::new(self, Level::Fatal, msg);
313 pub fn struct_span_fatal_with_code<'a, S: Into<MultiSpan>>(&'a self,
317 -> DiagnosticBuilder<'a> {
318 let mut result = DiagnosticBuilder::new(self, Level::Fatal, msg);
320 result.code(code.to_owned());
323 pub fn struct_fatal<'a>(&'a self, msg: &str) -> DiagnosticBuilder<'a> {
324 DiagnosticBuilder::new(self, Level::Fatal, msg)
327 pub fn cancel(&self, err: &mut DiagnosticBuilder) {
331 fn panic_if_treat_err_as_bug(&self) {
332 if self.treat_err_as_bug {
333 panic!("encountered error with `-Z treat_err_as_bug");
337 pub fn span_fatal<S: Into<MultiSpan>>(&self, sp: S, msg: &str) -> FatalError {
338 self.emit(&sp.into(), msg, Fatal);
339 self.panic_if_treat_err_as_bug();
342 pub fn span_fatal_with_code<S: Into<MultiSpan>>(&self,
347 self.emit_with_code(&sp.into(), msg, code, Fatal);
348 self.panic_if_treat_err_as_bug();
351 pub fn span_err<S: Into<MultiSpan>>(&self, sp: S, msg: &str) {
352 self.emit(&sp.into(), msg, Error);
353 self.panic_if_treat_err_as_bug();
355 pub fn mut_span_err<'a, S: Into<MultiSpan>>(&'a self,
358 -> DiagnosticBuilder<'a> {
359 let mut result = DiagnosticBuilder::new(self, Level::Error, msg);
363 pub fn span_err_with_code<S: Into<MultiSpan>>(&self, sp: S, msg: &str, code: &str) {
364 self.emit_with_code(&sp.into(), msg, code, Error);
365 self.panic_if_treat_err_as_bug();
367 pub fn span_warn<S: Into<MultiSpan>>(&self, sp: S, msg: &str) {
368 self.emit(&sp.into(), msg, Warning);
370 pub fn span_warn_with_code<S: Into<MultiSpan>>(&self, sp: S, msg: &str, code: &str) {
371 self.emit_with_code(&sp.into(), msg, code, Warning);
373 pub fn span_bug<S: Into<MultiSpan>>(&self, sp: S, msg: &str) -> ! {
374 self.emit(&sp.into(), msg, Bug);
377 pub fn delay_span_bug<S: Into<MultiSpan>>(&self, sp: S, msg: &str) {
378 let mut delayed = self.delayed_span_bug.borrow_mut();
379 *delayed = Some((sp.into(), msg.to_string()));
381 pub fn span_bug_no_panic<S: Into<MultiSpan>>(&self, sp: S, msg: &str) {
382 self.emit(&sp.into(), msg, Bug);
384 pub fn span_note_without_error<S: Into<MultiSpan>>(&self, sp: S, msg: &str) {
385 self.emit(&sp.into(), msg, Note);
387 pub fn span_unimpl<S: Into<MultiSpan>>(&self, sp: S, msg: &str) -> ! {
388 self.span_bug(sp, &format!("unimplemented {}", msg));
390 pub fn fatal(&self, msg: &str) -> FatalError {
391 if self.treat_err_as_bug {
394 let mut db = DiagnosticBuilder::new(self, Fatal, msg);
398 pub fn err(&self, msg: &str) {
399 if self.treat_err_as_bug {
402 let mut db = DiagnosticBuilder::new(self, Error, msg);
405 pub fn warn(&self, msg: &str) {
406 let mut db = DiagnosticBuilder::new(self, Warning, msg);
409 pub fn note_without_error(&self, msg: &str) {
410 let mut db = DiagnosticBuilder::new(self, Note, msg);
413 pub fn bug(&self, msg: &str) -> ! {
414 let mut db = DiagnosticBuilder::new(self, Bug, msg);
418 pub fn unimpl(&self, msg: &str) -> ! {
419 self.bug(&format!("unimplemented {}", msg));
422 pub fn bump_err_count(&self) {
423 self.err_count.set(self.err_count.get() + 1);
426 pub fn err_count(&self) -> usize {
430 pub fn has_errors(&self) -> bool {
431 self.err_count.get() > 0
433 pub fn abort_if_errors(&self) {
435 match self.err_count.get() {
437 let delayed_bug = self.delayed_span_bug.borrow();
439 Some((ref span, ref errmsg)) => {
440 self.span_bug(span.clone(), errmsg);
447 1 => s = "aborting due to previous error".to_string(),
449 s = format!("aborting due to {} previous errors", self.err_count.get());
453 panic!(self.fatal(&s));
455 pub fn emit(&self, msp: &MultiSpan, msg: &str, lvl: Level) {
456 if lvl == Warning && !self.can_emit_warnings {
459 let mut db = DiagnosticBuilder::new(self, lvl, msg);
460 db.set_span(msp.clone());
462 if !self.continue_after_error.get() {
463 self.abort_if_errors();
466 pub fn emit_with_code(&self, msp: &MultiSpan, msg: &str, code: &str, lvl: Level) {
467 if lvl == Warning && !self.can_emit_warnings {
470 let mut db = DiagnosticBuilder::new_with_code(self, lvl, Some(code.to_owned()), msg);
471 db.set_span(msp.clone());
473 if !self.continue_after_error.get() {
474 self.abort_if_errors();
480 #[derive(Copy, PartialEq, Clone, Debug, RustcEncodable, RustcDecodable)]
484 // An error which while not immediately fatal, should stop the compiler
485 // progressing beyond the current phase.
494 impl fmt::Display for Level {
495 fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
501 pub fn color(self) -> term::color::Color {
503 Bug | Fatal | PhaseFatal | Error => term::color::BRIGHT_RED,
506 term::color::BRIGHT_YELLOW
511 Note => term::color::BRIGHT_GREEN,
512 Help => term::color::BRIGHT_CYAN,
513 Cancelled => unreachable!(),
517 pub fn to_str(self) -> &'static str {
519 Bug => "error: internal compiler error",
520 Fatal | PhaseFatal | Error => "error",
521 Warning => "warning",
524 Cancelled => panic!("Shouldn't call on cancelled error"),
529 pub fn expect<T, M>(diag: &Handler, opt: Option<T>, msg: M) -> T
530 where M: FnOnce() -> String
534 None => diag.bug(&msg()),