1 // Copyright 2012 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 pub use self::Level::*;
12 pub use self::RenderSpan::*;
13 pub use self::ColorConfig::*;
14 use self::Destination::*;
16 use codemap::{COMMAND_LINE_SP, COMMAND_LINE_EXPN, Pos, Span};
20 use std::cell::{RefCell, Cell};
23 use std::string::String;
24 use term::WriterWrapper;
27 /// maximum number of lines we will print for each error; arbitrary.
28 static MAX_LINES: usize = 6;
30 #[derive(Clone, Copy)]
32 /// A FullSpan renders with both with an initial line for the
33 /// message, prefixed by file:linenum, followed by a summary of
34 /// the source code covered by the span.
37 /// A FileLine renders with just a line for the message prefixed
43 fn span(self) -> Span {
45 FullSpan(s) | FileLine(s) => s
48 fn is_full_span(&self) -> bool {
50 &FullSpan(..) => true,
51 &FileLine(..) => false,
56 #[derive(Clone, Copy)]
57 pub enum ColorConfig {
64 fn emit(&mut self, cmsp: Option<(&codemap::CodeMap, Span)>,
65 msg: &str, code: Option<&str>, lvl: Level);
66 fn custom_emit(&mut self, cm: &codemap::CodeMap,
67 sp: RenderSpan, msg: &str, lvl: Level);
70 /// This structure is used to signify that a task has panicked with a fatal error
71 /// from the diagnostics. You can use this with the `Any` trait to figure out
72 /// how a rustc task died (if so desired).
74 pub struct FatalError;
76 /// Signifies that the compiler died with an explicit call to `.bug`
77 /// or `.span_bug` rather than a failed assertion, etc.
79 pub struct ExplicitBug;
81 /// A span-handler is like a handler but also
82 /// accepts span information for source-location
84 pub struct SpanHandler {
86 pub cm: codemap::CodeMap,
90 pub fn span_fatal(&self, sp: Span, msg: &str) -> ! {
91 self.handler.emit(Some((&self.cm, sp)), msg, Fatal);
94 pub fn span_fatal_with_code(&self, sp: Span, msg: &str, code: &str) -> ! {
95 self.handler.emit_with_code(Some((&self.cm, sp)), msg, code, Fatal);
98 pub fn span_err(&self, sp: Span, msg: &str) {
99 self.handler.emit(Some((&self.cm, sp)), msg, Error);
100 self.handler.bump_err_count();
102 pub fn span_err_with_code(&self, sp: Span, msg: &str, code: &str) {
103 self.handler.emit_with_code(Some((&self.cm, sp)), msg, code, Error);
104 self.handler.bump_err_count();
106 pub fn span_warn(&self, sp: Span, msg: &str) {
107 self.handler.emit(Some((&self.cm, sp)), msg, Warning);
109 pub fn span_warn_with_code(&self, sp: Span, msg: &str, code: &str) {
110 self.handler.emit_with_code(Some((&self.cm, sp)), msg, code, Warning);
112 pub fn span_note(&self, sp: Span, msg: &str) {
113 self.handler.emit(Some((&self.cm, sp)), msg, Note);
115 pub fn span_end_note(&self, sp: Span, msg: &str) {
116 self.handler.custom_emit(&self.cm, FullSpan(sp), msg, Note);
118 pub fn span_help(&self, sp: Span, msg: &str) {
119 self.handler.emit(Some((&self.cm, sp)), msg, Help);
121 pub fn fileline_note(&self, sp: Span, msg: &str) {
122 self.handler.custom_emit(&self.cm, FileLine(sp), msg, Note);
124 pub fn fileline_help(&self, sp: Span, msg: &str) {
125 self.handler.custom_emit(&self.cm, FileLine(sp), msg, Help);
127 pub fn span_bug(&self, sp: Span, msg: &str) -> ! {
128 self.handler.emit(Some((&self.cm, sp)), msg, Bug);
131 pub fn span_unimpl(&self, sp: Span, msg: &str) -> ! {
132 self.span_bug(sp, &format!("unimplemented {}", msg));
134 pub fn handler<'a>(&'a self) -> &'a Handler {
139 /// A handler deals with errors; certain errors
140 /// (fatal, bug, unimpl) may cause immediate exit,
141 /// others log errors for later reporting.
143 err_count: Cell<usize>,
144 emit: RefCell<Box<Emitter + Send>>,
145 pub can_emit_warnings: bool
149 pub fn fatal(&self, msg: &str) -> ! {
150 self.emit.borrow_mut().emit(None, msg, None, Fatal);
153 pub fn err(&self, msg: &str) {
154 self.emit.borrow_mut().emit(None, msg, None, Error);
155 self.bump_err_count();
157 pub fn bump_err_count(&self) {
158 self.err_count.set(self.err_count.get() + 1);
160 pub fn err_count(&self) -> usize {
163 pub fn has_errors(&self) -> bool {
164 self.err_count.get() > 0
166 pub fn abort_if_errors(&self) {
168 match self.err_count.get() {
170 1 => s = "aborting due to previous error".to_string(),
172 s = format!("aborting due to {} previous errors",
173 self.err_count.get());
178 pub fn warn(&self, msg: &str) {
179 self.emit.borrow_mut().emit(None, msg, None, Warning);
181 pub fn note(&self, msg: &str) {
182 self.emit.borrow_mut().emit(None, msg, None, Note);
184 pub fn help(&self, msg: &str) {
185 self.emit.borrow_mut().emit(None, msg, None, Help);
187 pub fn bug(&self, msg: &str) -> ! {
188 self.emit.borrow_mut().emit(None, msg, None, Bug);
191 pub fn unimpl(&self, msg: &str) -> ! {
192 self.bug(&format!("unimplemented {}", msg));
195 cmsp: Option<(&codemap::CodeMap, Span)>,
198 if lvl == Warning && !self.can_emit_warnings { return }
199 self.emit.borrow_mut().emit(cmsp, msg, None, lvl);
201 pub fn emit_with_code(&self,
202 cmsp: Option<(&codemap::CodeMap, Span)>,
206 if lvl == Warning && !self.can_emit_warnings { return }
207 self.emit.borrow_mut().emit(cmsp, msg, Some(code), lvl);
209 pub fn custom_emit(&self, cm: &codemap::CodeMap,
210 sp: RenderSpan, msg: &str, lvl: Level) {
211 if lvl == Warning && !self.can_emit_warnings { return }
212 self.emit.borrow_mut().custom_emit(cm, sp, msg, lvl);
216 pub fn mk_span_handler(handler: Handler, cm: codemap::CodeMap) -> SpanHandler {
223 pub fn default_handler(color_config: ColorConfig,
224 registry: Option<diagnostics::registry::Registry>,
225 can_emit_warnings: bool) -> Handler {
226 mk_handler(can_emit_warnings, box EmitterWriter::stderr(color_config, registry))
229 pub fn mk_handler(can_emit_warnings: bool, e: Box<Emitter + Send>) -> Handler {
231 err_count: Cell::new(0),
232 emit: RefCell::new(e),
233 can_emit_warnings: can_emit_warnings
237 #[derive(Copy, PartialEq, Clone, Debug)]
247 impl fmt::Display for Level {
248 fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
249 use std::fmt::Display;
252 Bug => "error: internal compiler error".fmt(f),
253 Fatal | Error => "error".fmt(f),
254 Warning => "warning".fmt(f),
255 Note => "note".fmt(f),
256 Help => "help".fmt(f),
262 fn color(self) -> term::color::Color {
264 Bug | Fatal | Error => term::color::BRIGHT_RED,
265 Warning => term::color::BRIGHT_YELLOW,
266 Note => term::color::BRIGHT_GREEN,
267 Help => term::color::BRIGHT_CYAN,
272 fn print_maybe_styled(w: &mut EmitterWriter,
274 color: term::attr::Attr) -> old_io::IoResult<()> {
276 Terminal(ref mut t) => {
278 // If `msg` ends in a newline, we need to reset the color before
279 // the newline. We're making the assumption that we end up writing
280 // to a `LineBufferedWriter`, which means that emitting the reset
281 // after the newline ends up buffering the reset until we print
282 // another line or exit. Buffering the reset is a problem if we're
283 // sharing the terminal with any other programs (e.g. other rustc
284 // instances via `make -jN`).
286 // Note that if `msg` contains any internal newlines, this will
287 // result in the `LineBufferedWriter` flushing twice instead of
288 // once, which still leaves the opportunity for interleaved output
289 // to be miscolored. We assume this is rare enough that we don't
290 // have to worry about it.
291 if msg.ends_with("\n") {
292 try!(t.write_str(&msg[..msg.len()-1]));
294 try!(t.write_str("\n"));
296 try!(t.write_str(msg));
307 fn print_diagnostic(dst: &mut EmitterWriter, topic: &str, lvl: Level,
308 msg: &str, code: Option<&str>) -> old_io::IoResult<()> {
309 if !topic.is_empty() {
310 try!(write!(&mut dst.dst, "{} ", topic));
313 try!(print_maybe_styled(dst,
314 &format!("{}: ", lvl.to_string()),
315 term::attr::ForegroundColor(lvl.color())));
316 try!(print_maybe_styled(dst,
322 let style = term::attr::ForegroundColor(term::color::BRIGHT_MAGENTA);
323 try!(print_maybe_styled(dst, &format!(" [{}]", code.clone()), style));
327 try!(dst.dst.write_char('\n'));
331 pub struct EmitterWriter {
333 registry: Option<diagnostics::registry::Registry>
337 Terminal(Box<term::Terminal<WriterWrapper> + Send>),
338 Raw(Box<Writer + Send>),
342 pub fn stderr(color_config: ColorConfig,
343 registry: Option<diagnostics::registry::Registry>) -> EmitterWriter {
344 let stderr = old_io::stderr();
346 let use_color = match color_config {
349 Auto => stderr.get_ref().isatty()
353 let dst = match term::stderr() {
354 Some(t) => Terminal(t),
355 None => Raw(box stderr),
357 EmitterWriter { dst: dst, registry: registry }
359 EmitterWriter { dst: Raw(box stderr), registry: registry }
363 pub fn new(dst: Box<Writer + Send>,
364 registry: Option<diagnostics::registry::Registry>) -> EmitterWriter {
365 EmitterWriter { dst: Raw(dst), registry: registry }
369 impl Writer for Destination {
370 fn write_all(&mut self, bytes: &[u8]) -> old_io::IoResult<()> {
372 Terminal(ref mut t) => t.write_all(bytes),
373 Raw(ref mut w) => w.write_all(bytes),
378 impl Emitter for EmitterWriter {
380 cmsp: Option<(&codemap::CodeMap, Span)>,
381 msg: &str, code: Option<&str>, lvl: Level) {
382 let error = match cmsp {
383 Some((cm, COMMAND_LINE_SP)) => emit(self, cm,
384 FileLine(COMMAND_LINE_SP),
385 msg, code, lvl, false),
386 Some((cm, sp)) => emit(self, cm, FullSpan(sp), msg, code, lvl, false),
387 None => print_diagnostic(self, "", lvl, msg, code),
392 Err(e) => panic!("failed to print diagnostics: {:?}", e),
396 fn custom_emit(&mut self, cm: &codemap::CodeMap,
397 sp: RenderSpan, msg: &str, lvl: Level) {
398 match emit(self, cm, sp, msg, None, lvl, true) {
400 Err(e) => panic!("failed to print diagnostics: {:?}", e),
405 fn emit(dst: &mut EmitterWriter, cm: &codemap::CodeMap, rsp: RenderSpan,
406 msg: &str, code: Option<&str>, lvl: Level, custom: bool) -> old_io::IoResult<()> {
409 // We cannot check equality directly with COMMAND_LINE_SP
410 // since PartialEq is manually implemented to ignore the ExpnId
411 let ss = if sp.expn_id == COMMAND_LINE_EXPN {
412 "<command line option>".to_string()
414 cm.span_to_string(sp)
417 // we want to tell compiletest/runtest to look at the last line of the
418 // span (since `custom_highlight_lines` displays an arrow to the end of
420 let span_end = Span { lo: sp.hi, hi: sp.hi, expn_id: sp.expn_id};
421 let ses = cm.span_to_string(span_end);
422 try!(print_diagnostic(dst, &ses[..], lvl, msg, code));
423 if rsp.is_full_span() {
424 try!(custom_highlight_lines(dst, cm, sp, lvl, cm.span_to_lines(sp)));
427 try!(print_diagnostic(dst, &ss[..], lvl, msg, code));
428 if rsp.is_full_span() {
429 try!(highlight_lines(dst, cm, sp, lvl, cm.span_to_lines(sp)));
432 if sp != COMMAND_LINE_SP {
433 try!(print_macro_backtrace(dst, cm, sp));
437 match dst.registry.as_ref().and_then(|registry| registry.find_description(code)) {
439 try!(print_diagnostic(dst, &ss[..], Help,
440 &format!("pass `--explain {}` to see a detailed \
441 explanation", code), None));
450 fn highlight_lines(err: &mut EmitterWriter,
451 cm: &codemap::CodeMap,
454 lines: codemap::FileLines) -> old_io::IoResult<()> {
455 let fm = &*lines.file;
457 let mut elided = false;
458 let mut display_lines = &lines.lines[..];
459 if display_lines.len() > MAX_LINES {
460 display_lines = &display_lines[0..MAX_LINES];
463 // Print the offending lines
464 for &line_number in display_lines {
465 if let Some(line) = fm.get_line(line_number) {
466 try!(write!(&mut err.dst, "{}:{} {}\n", fm.name,
467 line_number + 1, line));
471 let last_line = display_lines[display_lines.len() - 1];
472 let s = format!("{}:{} ", fm.name, last_line + 1);
473 try!(write!(&mut err.dst, "{0:1$}...\n", "", s.len()));
477 // If there's one line at fault we can easily point to the problem
478 if lines.lines.len() == 1 {
479 let lo = cm.lookup_char_pos(sp.lo);
481 let mut num = (lines.lines[0] + 1) / 10;
483 // how many digits must be indent past?
484 while num > 0 { num /= 10; digits += 1; }
486 let mut s = String::new();
487 // Skip is the number of characters we need to skip because they are
488 // part of the 'filename:line ' part of the previous line.
489 let skip = fm.name.width(false) + digits + 3;
493 if let Some(orig) = fm.get_line(lines.lines[0]) {
496 let mut iter = orig.chars().enumerate();
497 for (pos, ch) in iter.by_ref() {
499 if pos >= lo.col.to_usize() { break; }
500 // Whenever a tab occurs on the previous line, we insert one on
501 // the error-point-squiggly-line as well (instead of a space).
502 // That way the squiggly line will usually appear in the correct
509 c => for _ in 0..c.width(false).unwrap_or(0) {
516 try!(write!(&mut err.dst, "{}", s));
517 let mut s = String::from_str("^");
518 let count = match lastc {
519 // Most terminals have a tab stop every eight columns by default
521 _ => lastc.width(false).unwrap_or(0),
524 s.extend(::std::iter::repeat('~').take(count));
526 let hi = cm.lookup_char_pos(sp.hi);
527 if hi.col != lo.col {
528 for (pos, ch) in iter {
529 if pos >= hi.col.to_usize() { break; }
530 let count = match ch {
532 _ => ch.width(false).unwrap_or(0),
535 s.extend(::std::iter::repeat('~').take(count));
540 // One extra squiggly is replaced by a "^"
544 try!(print_maybe_styled(err,
546 term::attr::ForegroundColor(lvl.color())));
552 /// Here are the differences between this and the normal `highlight_lines`:
553 /// `custom_highlight_lines` will always put arrow on the last byte of the
554 /// span (instead of the first byte). Also, when the span is too long (more
555 /// than 6 lines), `custom_highlight_lines` will print the first line, then
556 /// dot dot dot, then last line, whereas `highlight_lines` prints the first
558 fn custom_highlight_lines(w: &mut EmitterWriter,
559 cm: &codemap::CodeMap,
562 lines: codemap::FileLines)
563 -> old_io::IoResult<()> {
564 let fm = &*lines.file;
566 let lines = &lines.lines[..];
567 if lines.len() > MAX_LINES {
568 if let Some(line) = fm.get_line(lines[0]) {
569 try!(write!(&mut w.dst, "{}:{} {}\n", fm.name,
570 lines[0] + 1, line));
572 try!(write!(&mut w.dst, "...\n"));
573 let last_line_number = lines[lines.len() - 1];
574 if let Some(last_line) = fm.get_line(last_line_number) {
575 try!(write!(&mut w.dst, "{}:{} {}\n", fm.name,
576 last_line_number + 1, last_line));
579 for &line_number in lines {
580 if let Some(line) = fm.get_line(line_number) {
581 try!(write!(&mut w.dst, "{}:{} {}\n", fm.name,
582 line_number + 1, line));
586 let last_line_start = format!("{}:{} ", fm.name, lines[lines.len()-1]+1);
587 let hi = cm.lookup_char_pos(sp.hi);
588 let skip = last_line_start.width(false);
589 let mut s = String::new();
593 if let Some(orig) = fm.get_line(lines[0]) {
594 let iter = orig.chars().enumerate();
595 for (pos, ch) in iter {
596 // Span seems to use half-opened interval, so subtract 1
597 if pos >= hi.col.to_usize() - 1 { break; }
598 // Whenever a tab occurs on the previous line, we insert one on
599 // the error-point-squiggly-line as well (instead of a space).
600 // That way the squiggly line will usually appear in the correct
603 '\t' => s.push('\t'),
604 c => for _ in 0..c.width(false).unwrap_or(0) {
612 print_maybe_styled(w,
614 term::attr::ForegroundColor(lvl.color()))
617 fn print_macro_backtrace(w: &mut EmitterWriter,
618 cm: &codemap::CodeMap,
620 -> old_io::IoResult<()> {
621 let cs = try!(cm.with_expn_info(sp.expn_id, |expn_info| -> old_io::IoResult<_> {
624 let ss = ei.callee.span.map_or(String::new(),
625 |span| cm.span_to_string(span));
626 let (pre, post) = match ei.callee.format {
627 codemap::MacroAttribute => ("#[", "]"),
628 codemap::MacroBang => ("", "!")
630 try!(print_diagnostic(w, &ss, Note,
631 &format!("in expansion of {}{}{}", pre,
634 let ss = cm.span_to_string(ei.call_site);
635 try!(print_diagnostic(w, &ss, Note, "expansion site", None));
636 Ok(Some(ei.call_site))
641 cs.map_or(Ok(()), |call_site| print_macro_backtrace(w, cm, call_site))
644 pub fn expect<T, M>(diag: &SpanHandler, opt: Option<T>, msg: M) -> T where
645 M: FnOnce() -> String,
649 None => diag.handler().bug(&msg()),