/src/libsyntax/diagnostic.rs
Rust | 675 lines | 556 code | 52 blank | 67 comment | 56 complexity | 2d0946a74ca40452cf31b56ebfd7f296 MD5 | raw file
Possible License(s): AGPL-1.0, BSD-2-Clause, 0BSD, Apache-2.0, MIT, LGPL-2.0
- // Copyright 2012 The Rust Project Developers. See the COPYRIGHT
- // file at the top-level directory of this distribution and at
- // http://rust-lang.org/COPYRIGHT.
- //
- // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
- // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
- // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
- // option. This file may not be copied, modified, or distributed
- // except according to those terms.
- pub use self::Level::*;
- pub use self::RenderSpan::*;
- pub use self::ColorConfig::*;
- use self::Destination::*;
- use codemap::{COMMAND_LINE_SP, COMMAND_LINE_EXPN, Pos, Span};
- use codemap;
- use diagnostics;
- use std::cell::{RefCell, Cell};
- use std::fmt;
- use std::io::prelude::*;
- use std::io;
- use term::WriterWrapper;
- use term;
- use libc;
- /// maximum number of lines we will print for each error; arbitrary.
- const MAX_LINES: usize = 6;
- #[derive(Clone, Copy)]
- pub enum RenderSpan {
- /// A FullSpan renders with both with an initial line for the
- /// message, prefixed by file:linenum, followed by a summary of
- /// the source code covered by the span.
- FullSpan(Span),
- /// A FileLine renders with just a line for the message prefixed
- /// by file:linenum.
- FileLine(Span),
- }
- impl RenderSpan {
- fn span(self) -> Span {
- match self {
- FullSpan(s) | FileLine(s) => s
- }
- }
- fn is_full_span(&self) -> bool {
- match self {
- &FullSpan(..) => true,
- &FileLine(..) => false,
- }
- }
- }
- #[derive(Clone, Copy)]
- pub enum ColorConfig {
- Auto,
- Always,
- Never
- }
- pub trait Emitter {
- fn emit(&mut self, cmsp: Option<(&codemap::CodeMap, Span)>,
- msg: &str, code: Option<&str>, lvl: Level);
- fn custom_emit(&mut self, cm: &codemap::CodeMap,
- sp: RenderSpan, msg: &str, lvl: Level);
- }
- /// This structure is used to signify that a task has panicked with a fatal error
- /// from the diagnostics. You can use this with the `Any` trait to figure out
- /// how a rustc task died (if so desired).
- #[derive(Copy)]
- pub struct FatalError;
- /// Signifies that the compiler died with an explicit call to `.bug`
- /// or `.span_bug` rather than a failed assertion, etc.
- #[derive(Copy)]
- pub struct ExplicitBug;
- /// A span-handler is like a handler but also
- /// accepts span information for source-location
- /// reporting.
- pub struct SpanHandler {
- pub handler: Handler,
- pub cm: codemap::CodeMap,
- }
- impl SpanHandler {
- pub fn span_fatal(&self, sp: Span, msg: &str) -> ! {
- self.handler.emit(Some((&self.cm, sp)), msg, Fatal);
- panic!(FatalError);
- }
- pub fn span_fatal_with_code(&self, sp: Span, msg: &str, code: &str) -> ! {
- self.handler.emit_with_code(Some((&self.cm, sp)), msg, code, Fatal);
- panic!(FatalError);
- }
- pub fn span_err(&self, sp: Span, msg: &str) {
- self.handler.emit(Some((&self.cm, sp)), msg, Error);
- self.handler.bump_err_count();
- }
- pub fn span_err_with_code(&self, sp: Span, msg: &str, code: &str) {
- self.handler.emit_with_code(Some((&self.cm, sp)), msg, code, Error);
- self.handler.bump_err_count();
- }
- pub fn span_warn(&self, sp: Span, msg: &str) {
- self.handler.emit(Some((&self.cm, sp)), msg, Warning);
- }
- pub fn span_warn_with_code(&self, sp: Span, msg: &str, code: &str) {
- self.handler.emit_with_code(Some((&self.cm, sp)), msg, code, Warning);
- }
- pub fn span_note(&self, sp: Span, msg: &str) {
- self.handler.emit(Some((&self.cm, sp)), msg, Note);
- }
- pub fn span_end_note(&self, sp: Span, msg: &str) {
- self.handler.custom_emit(&self.cm, FullSpan(sp), msg, Note);
- }
- pub fn span_help(&self, sp: Span, msg: &str) {
- self.handler.emit(Some((&self.cm, sp)), msg, Help);
- }
- pub fn fileline_note(&self, sp: Span, msg: &str) {
- self.handler.custom_emit(&self.cm, FileLine(sp), msg, Note);
- }
- pub fn fileline_help(&self, sp: Span, msg: &str) {
- self.handler.custom_emit(&self.cm, FileLine(sp), msg, Help);
- }
- pub fn span_bug(&self, sp: Span, msg: &str) -> ! {
- self.handler.emit(Some((&self.cm, sp)), msg, Bug);
- panic!(ExplicitBug);
- }
- pub fn span_unimpl(&self, sp: Span, msg: &str) -> ! {
- self.span_bug(sp, &format!("unimplemented {}", msg));
- }
- pub fn handler<'a>(&'a self) -> &'a Handler {
- &self.handler
- }
- }
- /// A handler deals with errors; certain errors
- /// (fatal, bug, unimpl) may cause immediate exit,
- /// others log errors for later reporting.
- pub struct Handler {
- err_count: Cell<usize>,
- emit: RefCell<Box<Emitter + Send>>,
- pub can_emit_warnings: bool
- }
- impl Handler {
- pub fn fatal(&self, msg: &str) -> ! {
- self.emit.borrow_mut().emit(None, msg, None, Fatal);
- panic!(FatalError);
- }
- pub fn err(&self, msg: &str) {
- self.emit.borrow_mut().emit(None, msg, None, Error);
- self.bump_err_count();
- }
- pub fn bump_err_count(&self) {
- self.err_count.set(self.err_count.get() + 1);
- }
- pub fn err_count(&self) -> usize {
- self.err_count.get()
- }
- pub fn has_errors(&self) -> bool {
- self.err_count.get() > 0
- }
- pub fn abort_if_errors(&self) {
- let s;
- match self.err_count.get() {
- 0 => return,
- 1 => s = "aborting due to previous error".to_string(),
- _ => {
- s = format!("aborting due to {} previous errors",
- self.err_count.get());
- }
- }
- self.fatal(&s[..]);
- }
- pub fn warn(&self, msg: &str) {
- self.emit.borrow_mut().emit(None, msg, None, Warning);
- }
- pub fn note(&self, msg: &str) {
- self.emit.borrow_mut().emit(None, msg, None, Note);
- }
- pub fn help(&self, msg: &str) {
- self.emit.borrow_mut().emit(None, msg, None, Help);
- }
- pub fn bug(&self, msg: &str) -> ! {
- self.emit.borrow_mut().emit(None, msg, None, Bug);
- panic!(ExplicitBug);
- }
- pub fn unimpl(&self, msg: &str) -> ! {
- self.bug(&format!("unimplemented {}", msg));
- }
- pub fn emit(&self,
- cmsp: Option<(&codemap::CodeMap, Span)>,
- msg: &str,
- lvl: Level) {
- if lvl == Warning && !self.can_emit_warnings { return }
- self.emit.borrow_mut().emit(cmsp, msg, None, lvl);
- }
- pub fn emit_with_code(&self,
- cmsp: Option<(&codemap::CodeMap, Span)>,
- msg: &str,
- code: &str,
- lvl: Level) {
- if lvl == Warning && !self.can_emit_warnings { return }
- self.emit.borrow_mut().emit(cmsp, msg, Some(code), lvl);
- }
- pub fn custom_emit(&self, cm: &codemap::CodeMap,
- sp: RenderSpan, msg: &str, lvl: Level) {
- if lvl == Warning && !self.can_emit_warnings { return }
- self.emit.borrow_mut().custom_emit(cm, sp, msg, lvl);
- }
- }
- pub fn mk_span_handler(handler: Handler, cm: codemap::CodeMap) -> SpanHandler {
- SpanHandler {
- handler: handler,
- cm: cm,
- }
- }
- pub fn default_handler(color_config: ColorConfig,
- registry: Option<diagnostics::registry::Registry>,
- can_emit_warnings: bool) -> Handler {
- mk_handler(can_emit_warnings, Box::new(EmitterWriter::stderr(color_config, registry)))
- }
- pub fn mk_handler(can_emit_warnings: bool, e: Box<Emitter + Send>) -> Handler {
- Handler {
- err_count: Cell::new(0),
- emit: RefCell::new(e),
- can_emit_warnings: can_emit_warnings
- }
- }
- #[derive(Copy, PartialEq, Clone, Debug)]
- pub enum Level {
- Bug,
- Fatal,
- Error,
- Warning,
- Note,
- Help,
- }
- impl fmt::Display for Level {
- fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
- use std::fmt::Display;
- match *self {
- Bug => "error: internal compiler error".fmt(f),
- Fatal | Error => "error".fmt(f),
- Warning => "warning".fmt(f),
- Note => "note".fmt(f),
- Help => "help".fmt(f),
- }
- }
- }
- impl Level {
- fn color(self) -> term::color::Color {
- match self {
- Bug | Fatal | Error => term::color::BRIGHT_RED,
- Warning => term::color::BRIGHT_YELLOW,
- Note => term::color::BRIGHT_GREEN,
- Help => term::color::BRIGHT_CYAN,
- }
- }
- }
- fn print_maybe_styled(w: &mut EmitterWriter,
- msg: &str,
- color: term::attr::Attr) -> io::Result<()> {
- match w.dst {
- Terminal(ref mut t) => {
- try!(t.attr(color));
- // If `msg` ends in a newline, we need to reset the color before
- // the newline. We're making the assumption that we end up writing
- // to a `LineBufferedWriter`, which means that emitting the reset
- // after the newline ends up buffering the reset until we print
- // another line or exit. Buffering the reset is a problem if we're
- // sharing the terminal with any other programs (e.g. other rustc
- // instances via `make -jN`).
- //
- // Note that if `msg` contains any internal newlines, this will
- // result in the `LineBufferedWriter` flushing twice instead of
- // once, which still leaves the opportunity for interleaved output
- // to be miscolored. We assume this is rare enough that we don't
- // have to worry about it.
- if msg.ends_with("\n") {
- try!(t.write_all(msg[..msg.len()-1].as_bytes()));
- try!(t.reset());
- try!(t.write_all(b"\n"));
- } else {
- try!(t.write_all(msg.as_bytes()));
- try!(t.reset());
- }
- Ok(())
- }
- Raw(ref mut w) => w.write_all(msg.as_bytes()),
- }
- }
- fn print_diagnostic(dst: &mut EmitterWriter, topic: &str, lvl: Level,
- msg: &str, code: Option<&str>) -> io::Result<()> {
- if !topic.is_empty() {
- try!(write!(&mut dst.dst, "{} ", topic));
- }
- try!(print_maybe_styled(dst,
- &format!("{}: ", lvl.to_string()),
- term::attr::ForegroundColor(lvl.color())));
- try!(print_maybe_styled(dst,
- &format!("{}", msg),
- term::attr::Bold));
- match code {
- Some(code) => {
- let style = term::attr::ForegroundColor(term::color::BRIGHT_MAGENTA);
- try!(print_maybe_styled(dst, &format!(" [{}]", code.clone()), style));
- }
- None => ()
- }
- try!(write!(&mut dst.dst, "\n"));
- Ok(())
- }
- pub struct EmitterWriter {
- dst: Destination,
- registry: Option<diagnostics::registry::Registry>
- }
- enum Destination {
- Terminal(Box<term::Terminal<WriterWrapper> + Send>),
- Raw(Box<Write + Send>),
- }
- impl EmitterWriter {
- pub fn stderr(color_config: ColorConfig,
- registry: Option<diagnostics::registry::Registry>) -> EmitterWriter {
- let stderr = io::stderr();
- let use_color = match color_config {
- Always => true,
- Never => false,
- Auto => stderr_isatty(),
- };
- if use_color {
- let dst = match term::stderr() {
- Some(t) => Terminal(t),
- None => Raw(Box::new(stderr)),
- };
- EmitterWriter { dst: dst, registry: registry }
- } else {
- EmitterWriter { dst: Raw(Box::new(stderr)), registry: registry }
- }
- }
- pub fn new(dst: Box<Write + Send>,
- registry: Option<diagnostics::registry::Registry>) -> EmitterWriter {
- EmitterWriter { dst: Raw(dst), registry: registry }
- }
- }
- #[cfg(unix)]
- fn stderr_isatty() -> bool {
- unsafe { libc::isatty(libc::STDERR_FILENO) != 0 }
- }
- #[cfg(windows)]
- fn stderr_isatty() -> bool {
- const STD_ERROR_HANDLE: libc::DWORD = -12;
- extern "system" {
- fn GetStdHandle(which: libc::DWORD) -> libc::HANDLE;
- fn GetConsoleMode(hConsoleHandle: libc::HANDLE,
- lpMode: libc::LPDWORD) -> libc::BOOL;
- }
- unsafe {
- let handle = GetStdHandle(STD_ERROR_HANDLE);
- let mut out = 0;
- GetConsoleMode(handle, &mut out) != 0
- }
- }
- impl Write for Destination {
- fn write(&mut self, bytes: &[u8]) -> io::Result<usize> {
- match *self {
- Terminal(ref mut t) => t.write(bytes),
- Raw(ref mut w) => w.write(bytes),
- }
- }
- fn flush(&mut self) -> io::Result<()> {
- match *self {
- Terminal(ref mut t) => t.flush(),
- Raw(ref mut w) => w.flush(),
- }
- }
- }
- impl Emitter for EmitterWriter {
- fn emit(&mut self,
- cmsp: Option<(&codemap::CodeMap, Span)>,
- msg: &str, code: Option<&str>, lvl: Level) {
- let error = match cmsp {
- Some((cm, COMMAND_LINE_SP)) => emit(self, cm,
- FileLine(COMMAND_LINE_SP),
- msg, code, lvl, false),
- Some((cm, sp)) => emit(self, cm, FullSpan(sp), msg, code, lvl, false),
- None => print_diagnostic(self, "", lvl, msg, code),
- };
- match error {
- Ok(()) => {}
- Err(e) => panic!("failed to print diagnostics: {:?}", e),
- }
- }
- fn custom_emit(&mut self, cm: &codemap::CodeMap,
- sp: RenderSpan, msg: &str, lvl: Level) {
- match emit(self, cm, sp, msg, None, lvl, true) {
- Ok(()) => {}
- Err(e) => panic!("failed to print diagnostics: {:?}", e),
- }
- }
- }
- fn emit(dst: &mut EmitterWriter, cm: &codemap::CodeMap, rsp: RenderSpan,
- msg: &str, code: Option<&str>, lvl: Level, custom: bool) -> io::Result<()> {
- let sp = rsp.span();
- // We cannot check equality directly with COMMAND_LINE_SP
- // since PartialEq is manually implemented to ignore the ExpnId
- let ss = if sp.expn_id == COMMAND_LINE_EXPN {
- "<command line option>".to_string()
- } else {
- cm.span_to_string(sp)
- };
- if custom {
- // we want to tell compiletest/runtest to look at the last line of the
- // span (since `custom_highlight_lines` displays an arrow to the end of
- // the span)
- let span_end = Span { lo: sp.hi, hi: sp.hi, expn_id: sp.expn_id};
- let ses = cm.span_to_string(span_end);
- try!(print_diagnostic(dst, &ses[..], lvl, msg, code));
- if rsp.is_full_span() {
- try!(custom_highlight_lines(dst, cm, sp, lvl, cm.span_to_lines(sp)));
- }
- } else {
- try!(print_diagnostic(dst, &ss[..], lvl, msg, code));
- if rsp.is_full_span() {
- try!(highlight_lines(dst, cm, sp, lvl, cm.span_to_lines(sp)));
- }
- }
- if sp != COMMAND_LINE_SP {
- try!(print_macro_backtrace(dst, cm, sp));
- }
- match code {
- Some(code) =>
- match dst.registry.as_ref().and_then(|registry| registry.find_description(code)) {
- Some(_) => {
- try!(print_diagnostic(dst, &ss[..], Help,
- &format!("pass `--explain {}` to see a detailed \
- explanation", code), None));
- }
- None => ()
- },
- None => (),
- }
- Ok(())
- }
- fn highlight_lines(err: &mut EmitterWriter,
- cm: &codemap::CodeMap,
- sp: Span,
- lvl: Level,
- lines: codemap::FileLines) -> io::Result<()> {
- let fm = &*lines.file;
- let mut elided = false;
- let mut display_lines = &lines.lines[..];
- if display_lines.len() > MAX_LINES {
- display_lines = &display_lines[0..MAX_LINES];
- elided = true;
- }
- // Print the offending lines
- for &line_number in display_lines {
- if let Some(line) = fm.get_line(line_number) {
- try!(write!(&mut err.dst, "{}:{} {}\n", fm.name,
- line_number + 1, line));
- }
- }
- if elided {
- let last_line = display_lines[display_lines.len() - 1];
- let s = format!("{}:{} ", fm.name, last_line + 1);
- try!(write!(&mut err.dst, "{0:1$}...\n", "", s.len()));
- }
- // FIXME (#3260)
- // If there's one line at fault we can easily point to the problem
- if lines.lines.len() == 1 {
- let lo = cm.lookup_char_pos(sp.lo);
- let mut digits = 0;
- let mut num = (lines.lines[0] + 1) / 10;
- // how many digits must be indent past?
- while num > 0 { num /= 10; digits += 1; }
- let mut s = String::new();
- // Skip is the number of characters we need to skip because they are
- // part of the 'filename:line ' part of the previous line.
- let skip = fm.name.width(false) + digits + 3;
- for _ in 0..skip {
- s.push(' ');
- }
- if let Some(orig) = fm.get_line(lines.lines[0]) {
- let mut col = skip;
- let mut lastc = ' ';
- let mut iter = orig.chars().enumerate();
- for (pos, ch) in iter.by_ref() {
- lastc = ch;
- if pos >= lo.col.to_usize() { break; }
- // Whenever a tab occurs on the previous line, we insert one on
- // the error-point-squiggly-line as well (instead of a space).
- // That way the squiggly line will usually appear in the correct
- // position.
- match ch {
- '\t' => {
- col += 8 - col%8;
- s.push('\t');
- },
- c => for _ in 0..c.width(false).unwrap_or(0) {
- col += 1;
- s.push(' ');
- },
- }
- }
- try!(write!(&mut err.dst, "{}", s));
- let mut s = String::from_str("^");
- let count = match lastc {
- // Most terminals have a tab stop every eight columns by default
- '\t' => 8 - col%8,
- _ => lastc.width(false).unwrap_or(0),
- };
- col += count;
- s.extend(::std::iter::repeat('~').take(count));
- let hi = cm.lookup_char_pos(sp.hi);
- if hi.col != lo.col {
- for (pos, ch) in iter {
- if pos >= hi.col.to_usize() { break; }
- let count = match ch {
- '\t' => 8 - col%8,
- _ => ch.width(false).unwrap_or(0),
- };
- col += count;
- s.extend(::std::iter::repeat('~').take(count));
- }
- }
- if s.len() > 1 {
- // One extra squiggly is replaced by a "^"
- s.pop();
- }
- try!(print_maybe_styled(err,
- &format!("{}\n", s),
- term::attr::ForegroundColor(lvl.color())));
- }
- }
- Ok(())
- }
- /// Here are the differences between this and the normal `highlight_lines`:
- /// `custom_highlight_lines` will always put arrow on the last byte of the
- /// span (instead of the first byte). Also, when the span is too long (more
- /// than 6 lines), `custom_highlight_lines` will print the first line, then
- /// dot dot dot, then last line, whereas `highlight_lines` prints the first
- /// six lines.
- fn custom_highlight_lines(w: &mut EmitterWriter,
- cm: &codemap::CodeMap,
- sp: Span,
- lvl: Level,
- lines: codemap::FileLines)
- -> io::Result<()> {
- let fm = &*lines.file;
- let lines = &lines.lines[..];
- if lines.len() > MAX_LINES {
- if let Some(line) = fm.get_line(lines[0]) {
- try!(write!(&mut w.dst, "{}:{} {}\n", fm.name,
- lines[0] + 1, line));
- }
- try!(write!(&mut w.dst, "...\n"));
- let last_line_number = lines[lines.len() - 1];
- if let Some(last_line) = fm.get_line(last_line_number) {
- try!(write!(&mut w.dst, "{}:{} {}\n", fm.name,
- last_line_number + 1, last_line));
- }
- } else {
- for &line_number in lines {
- if let Some(line) = fm.get_line(line_number) {
- try!(write!(&mut w.dst, "{}:{} {}\n", fm.name,
- line_number + 1, line));
- }
- }
- }
- let last_line_start = format!("{}:{} ", fm.name, lines[lines.len()-1]+1);
- let hi = cm.lookup_char_pos(sp.hi);
- let skip = last_line_start.width(false);
- let mut s = String::new();
- for _ in 0..skip {
- s.push(' ');
- }
- if let Some(orig) = fm.get_line(lines[0]) {
- let iter = orig.chars().enumerate();
- for (pos, ch) in iter {
- // Span seems to use half-opened interval, so subtract 1
- if pos >= hi.col.to_usize() - 1 { break; }
- // Whenever a tab occurs on the previous line, we insert one on
- // the error-point-squiggly-line as well (instead of a space).
- // That way the squiggly line will usually appear in the correct
- // position.
- match ch {
- '\t' => s.push('\t'),
- c => for _ in 0..c.width(false).unwrap_or(0) {
- s.push(' ');
- },
- }
- }
- }
- s.push('^');
- s.push('\n');
- print_maybe_styled(w,
- &s[..],
- term::attr::ForegroundColor(lvl.color()))
- }
- fn print_macro_backtrace(w: &mut EmitterWriter,
- cm: &codemap::CodeMap,
- sp: Span)
- -> io::Result<()> {
- let cs = try!(cm.with_expn_info(sp.expn_id, |expn_info| -> io::Result<_> {
- match expn_info {
- Some(ei) => {
- let ss = ei.callee.span.map_or(String::new(),
- |span| cm.span_to_string(span));
- let (pre, post) = match ei.callee.format {
- codemap::MacroAttribute => ("#[", "]"),
- codemap::MacroBang => ("", "!")
- };
- try!(print_diagnostic(w, &ss, Note,
- &format!("in expansion of {}{}{}", pre,
- ei.callee.name,
- post), None));
- let ss = cm.span_to_string(ei.call_site);
- try!(print_diagnostic(w, &ss, Note, "expansion site", None));
- Ok(Some(ei.call_site))
- }
- None => Ok(None)
- }
- }));
- cs.map_or(Ok(()), |call_site| print_macro_backtrace(w, cm, call_site))
- }
- pub fn expect<T, M>(diag: &SpanHandler, opt: Option<T>, msg: M) -> T where
- M: FnOnce() -> String,
- {
- match opt {
- Some(t) => t,
- None => diag.handler().bug(&msg()),
- }
- }