rust/src/libsyntax/diagnostic.rs
2013-05-28 03:14:44 +09:00

314 lines
9.4 KiB
Rust

// 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.
use core::prelude::*;
use codemap::{Pos, span};
use codemap;
use extra::term;
pub type Emitter = @fn(cmsp: Option<(@codemap::CodeMap, span)>,
msg: &str,
lvl: level);
// a handler deals with errors; certain errors
// (fatal, bug, unimpl) may cause immediate exit,
// others log errors for later reporting.
pub trait handler {
fn fatal(@mut self, msg: &str) -> !;
fn err(@mut self, msg: &str);
fn bump_err_count(@mut self);
fn err_count(@mut self) -> uint;
fn has_errors(@mut self) -> bool;
fn abort_if_errors(@mut self);
fn warn(@mut self, msg: &str);
fn note(@mut self, msg: &str);
// used to indicate a bug in the compiler:
fn bug(@mut self, msg: &str) -> !;
fn unimpl(@mut self, msg: &str) -> !;
fn emit(@mut self,
cmsp: Option<(@codemap::CodeMap, span)>,
msg: &str,
lvl: level);
}
// a span-handler is like a handler but also
// accepts span information for source-location
// reporting.
pub trait span_handler {
fn span_fatal(@mut self, sp: span, msg: &str) -> !;
fn span_err(@mut self, sp: span, msg: &str);
fn span_warn(@mut self, sp: span, msg: &str);
fn span_note(@mut self, sp: span, msg: &str);
fn span_bug(@mut self, sp: span, msg: &str) -> !;
fn span_unimpl(@mut self, sp: span, msg: &str) -> !;
fn handler(@mut self) -> @handler;
}
struct HandlerT {
err_count: uint,
emit: Emitter,
}
struct CodemapT {
handler: @handler,
cm: @codemap::CodeMap,
}
impl span_handler for CodemapT {
fn span_fatal(@mut self, sp: span, msg: &str) -> ! {
self.handler.emit(Some((self.cm, sp)), msg, fatal);
fail!();
}
fn span_err(@mut self, sp: span, msg: &str) {
self.handler.emit(Some((self.cm, sp)), msg, error);
self.handler.bump_err_count();
}
fn span_warn(@mut self, sp: span, msg: &str) {
self.handler.emit(Some((self.cm, sp)), msg, warning);
}
fn span_note(@mut self, sp: span, msg: &str) {
self.handler.emit(Some((self.cm, sp)), msg, note);
}
fn span_bug(@mut self, sp: span, msg: &str) -> ! {
self.span_fatal(sp, ice_msg(msg));
}
fn span_unimpl(@mut self, sp: span, msg: &str) -> ! {
self.span_bug(sp, ~"unimplemented " + msg);
}
fn handler(@mut self) -> @handler {
self.handler
}
}
impl handler for HandlerT {
fn fatal(@mut self, msg: &str) -> ! {
(self.emit)(None, msg, fatal);
fail!();
}
fn err(@mut self, msg: &str) {
(self.emit)(None, msg, error);
self.bump_err_count();
}
fn bump_err_count(@mut self) {
self.err_count += 1u;
}
fn err_count(@mut self) -> uint {
self.err_count
}
fn has_errors(@mut self) -> bool {
self.err_count > 0u
}
fn abort_if_errors(@mut self) {
let s;
match self.err_count {
0u => return,
1u => s = ~"aborting due to previous error",
_ => {
s = fmt!("aborting due to %u previous errors",
self.err_count);
}
}
self.fatal(s);
}
fn warn(@mut self, msg: &str) {
(self.emit)(None, msg, warning);
}
fn note(@mut self, msg: &str) {
(self.emit)(None, msg, note);
}
fn bug(@mut self, msg: &str) -> ! {
self.fatal(ice_msg(msg));
}
fn unimpl(@mut self, msg: &str) -> ! {
self.bug(~"unimplemented " + msg);
}
fn emit(@mut self,
cmsp: Option<(@codemap::CodeMap, span)>,
msg: &str,
lvl: level) {
(self.emit)(cmsp, msg, lvl);
}
}
pub fn ice_msg(msg: &str) -> ~str {
fmt!("internal compiler error: %s", msg)
}
pub fn mk_span_handler(handler: @handler, cm: @codemap::CodeMap)
-> @span_handler {
@mut CodemapT { handler: handler, cm: cm } as @span_handler
}
pub fn mk_handler(emitter: Option<Emitter>) -> @handler {
let emit: Emitter = match emitter {
Some(e) => e,
None => {
let emit: Emitter = |cmsp, msg, t| emit(cmsp, msg, t);
emit
}
};
@mut HandlerT { err_count: 0, emit: emit } as @handler
}
#[deriving(Eq)]
pub enum level {
fatal,
error,
warning,
note,
}
fn diagnosticstr(lvl: level) -> ~str {
match lvl {
fatal => ~"error",
error => ~"error",
warning => ~"warning",
note => ~"note"
}
}
fn diagnosticcolor(lvl: level) -> u8 {
match lvl {
fatal => term::color_bright_red,
error => term::color_bright_red,
warning => term::color_bright_yellow,
note => term::color_bright_green
}
}
fn print_diagnostic(topic: &str, lvl: level, msg: &str) {
let use_color = term::color_supported() &&
io::stderr().get_type() == io::Screen;
if !topic.is_empty() {
io::stderr().write_str(fmt!("%s ", topic));
}
if use_color {
term::fg(io::stderr(), diagnosticcolor(lvl));
}
io::stderr().write_str(fmt!("%s:", diagnosticstr(lvl)));
if use_color {
term::reset(io::stderr());
}
io::stderr().write_str(fmt!(" %s\n", msg));
}
pub fn collect(messages: @mut ~[~str])
-> @fn(Option<(@codemap::CodeMap, span)>, &str, level) {
let f: @fn(Option<(@codemap::CodeMap, span)>, &str, level) =
|_o, msg: &str, _l| { messages.push(msg.to_str()); };
f
}
pub fn emit(cmsp: Option<(@codemap::CodeMap, span)>, msg: &str, lvl: level) {
match cmsp {
Some((cm, sp)) => {
let sp = cm.adjust_span(sp);
let ss = cm.span_to_str(sp);
let lines = cm.span_to_lines(sp);
print_diagnostic(ss, lvl, msg);
highlight_lines(cm, sp, lines);
print_macro_backtrace(cm, sp);
}
None => {
print_diagnostic("", lvl, msg);
}
}
}
fn highlight_lines(cm: @codemap::CodeMap,
sp: span,
lines: @codemap::FileLines) {
let fm = lines.file;
// arbitrarily only print up to six lines of the error
let max_lines = 6u;
let mut elided = false;
let mut display_lines = /* FIXME (#2543) */ copy lines.lines;
if display_lines.len() > max_lines {
display_lines = vec::slice(display_lines, 0u, max_lines).to_vec();
elided = true;
}
// Print the offending lines
for display_lines.each |line| {
io::stderr().write_str(fmt!("%s:%u ", fm.name, *line + 1u));
let s = fm.get_line(*line as int) + "\n";
io::stderr().write_str(s);
}
if elided {
let last_line = display_lines[display_lines.len() - 1u];
let s = fmt!("%s:%u ", fm.name, last_line + 1u);
let mut indent = str::len(s);
let mut out = ~"";
while indent > 0u { out += " "; indent -= 1u; }
out += "...\n";
io::stderr().write_str(out);
}
// FIXME (#3260)
// If there's one line at fault we can easily point to the problem
if lines.lines.len() == 1u {
let lo = cm.lookup_char_pos(sp.lo);
let mut digits = 0u;
let mut num = (lines.lines[0] + 1u) / 10u;
// how many digits must be indent past?
while num > 0u { num /= 10u; digits += 1u; }
// indent past |name:## | and the 0-offset column location
let left = str::len(fm.name) + digits + lo.col.to_uint() + 3u;
let mut s = ~"";
// 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 = str::len(fm.name) + digits + 3u;
for skip.times() {
s += " ";
}
let orig = fm.get_line(lines.lines[0] as int);
for uint::range(0u,left-skip) |pos| {
let curChar = (orig[pos] as char);
s += match curChar { // Whenever a tab occurs on the previous
'\t' => "\t", // line, we insert one on the error-point-
_ => " " // -squigly-line as well (instead of a
}; // space). This way the squigly-line will
} // usually appear in the correct position.
s += "^";
let hi = cm.lookup_char_pos(sp.hi);
if hi.col != lo.col {
// the ^ already takes up one space
let num_squiglies = hi.col.to_uint()-lo.col.to_uint()-1u;
for num_squiglies.times() { s += "~"; }
}
io::stderr().write_str(s + "\n");
}
}
fn print_macro_backtrace(cm: @codemap::CodeMap, sp: span) {
for sp.expn_info.each |ei| {
let ss = ei.callee.span.map_default(@~"", |span| @cm.span_to_str(*span));
print_diagnostic(*ss, note,
fmt!("in expansion of %s!", ei.callee.name));
let ss = cm.span_to_str(ei.call_site);
print_diagnostic(ss, note, "expansion site");
print_macro_backtrace(cm, ei.call_site);
}
}
pub fn expect<T:Copy>(diag: @span_handler,
opt: Option<T>,
msg: &fn() -> ~str) -> T {
match opt {
Some(ref t) => (*t),
None => diag.handler().bug(msg())
}
}