// Copyright 2012-2015 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 self::Destination::*;
use syntax_pos::{DUMMY_SP, FileMap, Span, MultiSpan};
use {Level, CodeSuggestion, DiagnosticBuilder, SubDiagnostic, CodeMapper, DiagnosticId};
use snippet::{Annotation, AnnotationType, Line, MultilineAnnotation, StyledString, Style};
use styled_buffer::StyledBuffer;
use std::borrow::Cow;
use std::io::prelude::*;
use std::io;
use std::rc::Rc;
use term;
use std::collections::HashMap;
use std::cmp::min;
use unicode_width;
/// Emitter trait for emitting errors.
pub trait Emitter {
/// Emit a structured diagnostic.
fn emit(&mut self, db: &DiagnosticBuilder);
}
impl Emitter for EmitterWriter {
fn emit(&mut self, db: &DiagnosticBuilder) {
let mut primary_span = db.span.clone();
let mut children = db.children.clone();
let mut suggestions: &[_] = &[];
if let Some((sugg, rest)) = db.suggestions.split_first() {
if rest.is_empty() &&
// don't display multi-suggestions as labels
sugg.substitutions.len() == 1 &&
// don't display multipart suggestions as labels
sugg.substitutions[0].parts.len() == 1 &&
// don't display long messages as labels
sugg.msg.split_whitespace().count() < 10 &&
// don't display multiline suggestions as labels
!sugg.substitutions[0].parts[0].snippet.contains('\n') {
let substitution = &sugg.substitutions[0].parts[0].snippet.trim();
let msg = if substitution.len() == 0 || !sugg.show_code_when_inline {
// This substitution is only removal or we explicitly don't want to show the
// code inline, don't show it
format!("help: {}", sugg.msg)
} else {
format!("help: {}: `{}`", sugg.msg, substitution)
};
primary_span.push_span_label(sugg.substitutions[0].parts[0].span, msg);
} else {
// if there are multiple suggestions, print them all in full
// to be consistent. We could try to figure out if we can
// make one (or the first one) inline, but that would give
// undue importance to a semi-random suggestion
suggestions = &db.suggestions;
}
}
self.fix_multispans_in_std_macros(&mut primary_span,
&mut children,
db.handler.flags.external_macro_backtrace);
self.emit_messages_default(&db.level,
&db.styled_message(),
&db.code,
&primary_span,
&children,
&suggestions);
}
}
/// maximum number of lines we will print for each error; arbitrary.
pub const MAX_HIGHLIGHT_LINES: usize = 6;
/// maximum number of suggestions to be shown
///
/// Arbitrary, but taken from trait import suggestion limit
pub const MAX_SUGGESTIONS: usize = 4;
#[derive(Clone, Copy, Debug, PartialEq, Eq)]
pub enum ColorConfig {
Auto,
Always,
Never,
}
impl ColorConfig {
fn use_color(&self) -> bool {
match *self {
ColorConfig::Always => true,
ColorConfig::Never => false,
ColorConfig::Auto => stderr_isatty(),
}
}
}
pub struct EmitterWriter {
dst: Destination,
cm: Option<Rc<CodeMapper>>,
short_message: bool,
}
struct FileWithAnnotatedLines {
file: Rc<FileMap>,
lines: Vec<Line>,
multiline_depth: usize,
}
impl EmitterWriter {
pub fn stderr(color_config: ColorConfig,
code_map: Option<Rc<CodeMapper>>,
short_message: bool)
-> EmitterWriter {
if color_config.use_color() {
let dst = Destination::from_stderr();
EmitterWriter {
dst,
cm: code_map,
short_message: short_message,
}
} else {
EmitterWriter {
dst: Raw(Box::new(io::stderr())),
cm: code_map,
short_message: short_message,
}
}
}
pub fn new(dst: Box<Write + Send>,
code_map: Option<Rc<CodeMapper>>,
short_message: bool)
-> EmitterWriter {
EmitterWriter {
dst: Raw(dst),
cm: code_map,
short_message: short_message,
}
}
fn preprocess_annotations(&mut self, msp: &MultiSpan) -> Vec<FileWithAnnotatedLines> {
fn add_annotation_to_file(file_vec: &mut Vec<FileWithAnnotatedLines>,
file: Rc<FileMap>,
line_index: usize,
ann: Annotation) {
for slot in file_vec.iter_mut() {
// Look through each of our files for the one we're adding to
if slot.file.name == file.name {
// See if we already have a line for it
for line_slot in &mut slot.lines {
if line_slot.line_index == line_index {
line_slot.annotations.push(ann);
return;
}
}
// We don't have a line yet, create one
slot.lines.push(Line {
line_index,
annotations: vec![ann],
});
slot.lines.sort();
return;
}
}
// This is the first time we're seeing the file
file_vec.push(FileWithAnnotatedLines {
file,
lines: vec![Line {
line_index,
annotations: vec![ann],
}],
multiline_depth: 0,
});
}
let mut output = vec![];
let mut multiline_annotations = vec![];
if let Some(ref cm) = self.cm {
for span_label in msp.span_labels() {
if span_label.span == DUMMY_SP {
continue;
}
let lo = cm.lookup_char_pos(span_label.span.lo());
let mut hi = cm.lookup_char_pos(span_label.span.hi());
// Watch out for "empty spans". If we get a span like 6..6, we
// want to just display a `^` at 6, so convert that to
// 6..7. This is degenerate input, but it's best to degrade
// gracefully -- and the parser likes to supply a span like
// that for EOF, in particular.
if lo.col_display == hi.col_display && lo.line == hi.line {
hi.col_display += 1;
}
let ann_type = if lo.line != hi.line {
let ml = MultilineAnnotation {
depth: 1,
line_start: lo.line,
line_end: hi.line,
start_col: lo.col_display,
end_col: hi.col_display,
is_primary: span_label.is_primary,
label: span_label.label.clone(),
};
multiline_annotations.push((lo.file.clone(), ml.clone()));
AnnotationType::Multiline(ml)
} else {
AnnotationType::Singleline
};
let ann = Annotation {
start_col: lo.col_display,
end_col: hi.col_display,
is_primary: span_label.is_primary,
label: span_label.label.clone(),
annotation_type: ann_type,
};
if !ann.is_multiline() {
add_annotation_to_file(&mut output,
lo.file,
lo.line,
ann);
}
}
}
// Find overlapping multiline annotations, put them at different depths
multiline_annotations.sort_by(|a, b| {
(a.1.line_start, a.1.line_end).cmp(&(b.1.line_start, b.1.line_end))
});
for item in multiline_annotations.clone() {
let ann = item.1;
for item in multiline_annotations.iter_mut() {
let ref mut a = item.1;
// Move all other multiline annotations overlapping with this one
// one level to the right.
if &ann != a &&
num_overlap(ann.line_start, ann.line_end, a.line_start, a.line_end, true)
{
a.increase_depth();
} else {
break;
}
}
}
let mut max_depth = 0; // max overlapping multiline spans
for (file, ann) in multiline_annotations {
if ann.depth > max_depth {
max_depth = ann.depth;
}
add_annotation_to_file(&mut output, file.clone(), ann.line_start, ann.as_start());
let middle = min(ann.line_start + 4, ann.line_end);
for line in ann.line_start + 1..middle {
add_annotation_to_file(&mut output, file.clone(), line, ann.as_line());
}
if middle < ann.line_end - 1 {
for line in ann.line_end - 1..ann.line_end {
add_annotation_to_file(&mut output, file.clone(), line, ann.as_line());
}
}
add_annotation_to_file(&mut output, file, ann.line_end, ann.as_end());
}
for file_vec in output.iter_mut() {
file_vec.multiline_depth = max_depth;
}
output
}
fn render_source_line(&self,
buffer: &mut StyledBuffer,
file: Rc<FileMap>,
line: &Line,
width_offset: usize,
code_offset: usize) -> Vec<(usize, Style)> {
let source_string = match file.get_line(line.line_index - 1) {
Some(s) => s,
None => return Vec::new(),
};
let line_offset = buffer.num_lines();
// First create the source line we will highlight.
buffer.puts(line_offset, code_offset, &source_string, Style::Quotation);
buffer.puts(line_offset,
0,
&(line.line_index.to_string()),
Style::LineNumber);
draw_col_separator(buffer, line_offset, width_offset - 2);
// Special case when there's only one annotation involved, it is the start of a multiline
// span and there's no text at the beginning of the code line. Instead of doing the whole
// graph:
//
// 2 | fn foo() {
// | _^
// 3 | |
// 4 | | }
// | |_^ test
//
// we simplify the output to:
//
// 2 | / fn foo() {
// 3 | |
// 4 | | }
// | |_^ test
if line.annotations.len() == 1 {
if let Some(ref ann) = line.annotations.get(0) {
if let AnnotationType::MultilineStart(depth) = ann.annotation_type {
if source_string.chars()
.take(ann.start_col)
.all(|c| c.is_whitespace()) {
let style = if ann.is_primary {
Style::UnderlinePrimary
} else {
Style::UnderlineSecondary
};
buffer.putc(line_offset,
width_offset + depth - 1,
'/',
style);
return vec![(depth, style)];
}
}
}
}
// We want to display like this:
//
// vec.push(vec.pop().unwrap());
// --- ^^^ - previous borrow ends here
// | |
// | error occurs here
// previous borrow of `vec` occurs here
//
// But there are some weird edge cases to be aware of:
//
// vec.push(vec.pop().unwrap());
// -------- - previous borrow ends here
// ||
// |this makes no sense
// previous borrow of `vec` occurs here
//
// For this reason, we group the lines into "highlight lines"
// and "annotations lines", where the highlight lines have the `^`.
// Sort the annotations by (start, end col)
// The labels are reversed, sort and then reversed again.
// Consider a list of annotations (A1, A2, C1, C2, B1, B2) where
// the letter signifies the span. Here we are only sorting by the
// span and hence, the order of the elements with the same span will
// not change. On reversing the ordering (|a, b| but b.cmp(a)), you get
// (C1, C2, B1, B2, A1, A2). All the elements with the same span are
// still ordered first to last, but all the elements with different
// spans are ordered by their spans in last to first order. Last to
// first order is important, because the jiggly lines and | are on
// the left, so the rightmost span needs to be rendered first,
// otherwise the lines would end up needing to go over a message.
let mut annotations = line.annotations.clone();
annotations.sort_by(|a,b| b.start_col.cmp(&a.start_col));
// First, figure out where each label will be positioned.
//
// In the case where you have the following annotations:
//
// vec.push(vec.pop().unwrap());
// -------- - previous borrow ends here [C]
// ||
// |this makes no sense [B]
// previous borrow of `vec` occurs here [A]
//
// `annotations_position` will hold [(2, A), (1, B), (0, C)].
//
// We try, when possible, to stick the rightmost annotation at the end
// of the highlight line:
//
// vec.push(vec.pop().unwrap());
// --- --- - previous borrow ends here
//
// But sometimes that's not possible because one of the other
// annotations overlaps it. For example, from the test
// `span_overlap_label`, we have the following annotations
// (written on distinct lines for clarity):
//
// fn foo(x: u32) {
// --------------
// -
//
// In this case, we can't stick the rightmost-most label on
// the highlight line, or we would get:
//
// fn foo(x: u32) {
// -------- x_span
// |
// fn_span
//
// which is totally weird. Instead we want:
//
// fn foo(x: u32) {
// --------------
// | |
// | x_span
// fn_span
//
// which is...less weird, at least. In fact, in general, if
// the rightmost span overlaps with any other span, we should
// use the "hang below" version, so we can at least make it
// clear where the span *starts*. There's an exception for this
// logic, when the labels do not have a message:
//
// fn foo(x: u32) {
// --------------
// |
// x_span
//
// instead of:
//
// fn foo(x: u32) {
// --------------
// | |
// | x_span
// <EMPTY LINE>
//
let mut annotations_position = vec![];
let mut line_len = 0;
let mut p = 0;
for (i, annotation) in annotations.iter().enumerate() {
for (j, next) in annotations.iter().enumerate() {
if overlaps(next, annotation, 0) // This label overlaps with another one and both
&& annotation.has_label() // take space (they have text and are not
&& j > i // multiline lines).
&& p == 0 // We're currently on the first line, move the label one line down
{
// This annotation needs a new line in the output.
p += 1;
break;
}
}
annotations_position.push((p, annotation));
for (j, next) in annotations.iter().enumerate() {
if j > i {
let l = if let Some(ref label) = next.label {
label.len() + 2
} else {
0
};
if (overlaps(next, annotation, l) // Do not allow two labels to be in the same
// line if they overlap including padding, to
// avoid situations like:
//
// fn foo(x: u32) {
// -------^------
// | |
// fn_spanx_span
//
&& annotation.has_label() // Both labels must have some text, otherwise
&& next.has_label()) // they are not overlapping.
// Do not add a new line if this annotation
// or the next are vertical line placeholders.
|| (annotation.takes_space() // If either this or the next annotation is
&& next.has_label()) // multiline start/end, move it to a new line
|| (annotation.has_label() // so as not to overlap the orizontal lines.
&& next.takes_space())
|| (annotation.takes_space() && next.takes_space())
|| (overlaps(next, annotation, l)
&& next.end_col <= annotation.end_col
&& next.has_label()
&& p == 0) // Avoid #42595.
{
// This annotation needs a new line in the output.
p += 1;
break;
}
}
}
if line_len < p {
line_len = p;
}
}
if line_len != 0 {
line_len += 1;
}
// If there are no annotations or the only annotations on this line are
// MultilineLine, then there's only code being shown, stop processing.
if line.annotations.is_empty() || line.annotations.iter()
.filter(|a| !a.is_line()).collect::<Vec<_>>().len() == 0
{
return vec![];
}
// Write the colunmn separator.
//
// After this we will have:
//
// 2 | fn foo() {
// |
// |
// |
// 3 |
// 4 | }
// |
for pos in 0..line_len + 1 {
draw_col_separator(buffer, line_offset + pos + 1, width_offset - 2);
buffer.putc(line_offset + pos + 1,
width_offset - 2,
'|',
Style::LineNumber);
}
// Write the horizontal lines for multiline annotations
// (only the first and last lines need this).
//
// After this we will have:
//
// 2 | fn foo() {
// | __________
// |
// |
// 3 |
// 4 | }
// | _
for &(pos, annotation) in &annotations_position {
let style = if annotation.is_primary {
Style::UnderlinePrimary
} else {
Style::UnderlineSecondary
};
let pos = pos + 1;
match annotation.annotation_type {
AnnotationType::MultilineStart(depth) |
AnnotationType::MultilineEnd(depth) => {
draw_range(buffer,
'_',
line_offset + pos,
width_offset + depth,
code_offset + annotation.start_col,
style);
}
_ => (),
}
}
// Write the vertical lines for labels that are on a different line as the underline.
//
// After this we will have:
//
// 2 | fn foo() {
// | __________
// | | |
// | |
// 3 |
// 4 | | }
// | |_
for &(pos, annotation) in &annotations_position {
let style = if annotation.is_primary {
Style::UnderlinePrimary
} else {
Style::UnderlineSecondary
};
let pos = pos + 1;
if pos > 1 && (annotation.has_label() || annotation.takes_space()) {
for p in line_offset + 1..line_offset + pos + 1 {
buffer.putc(p,
code_offset + annotation.start_col,
'|',
style);
}
}
match annotation.annotation_type {
AnnotationType::MultilineStart(depth) => {
for p in line_offset + pos + 1..line_offset + line_len + 2 {
buffer.putc(p,
width_offset + depth - 1,
'|',
style);
}
}
AnnotationType::MultilineEnd(depth) => {
for p in line_offset..line_offset + pos + 1 {
buffer.putc(p,
width_offset + depth - 1,
'|',
style);
}
}
_ => (),
}
}
// Write the labels on the annotations that actually have a label.
//
// After this we will have:
//
// 2 | fn foo() {
// | __________
// | |
// | something about `foo`
// 3 |
// 4 | }
// | _ test
for &(pos, annotation) in &annotations_position {
let style = if annotation.is_primary {
Style::LabelPrimary
} else {
Style::LabelSecondary
};
let (pos, col) = if pos == 0 {
(pos + 1, annotation.end_col + 1)
} else {
(pos + 2, annotation.start_col)
};
if let Some(ref label) = annotation.label {
buffer.puts(line_offset + pos,
code_offset + col,
&label,
style);
}
}
// Sort from biggest span to smallest span so that smaller spans are
// represented in the output:
//
// x | fn foo()
// | ^^^---^^
// | | |
// | | something about `foo`
// | something about `fn foo()`
annotations_position.sort_by(|a, b| {
// Decreasing order
a.1.len().cmp(&b.1.len()).reverse()
});
// Write the underlines.
//
// After this we will have:
//
// 2 | fn foo() {
// | ____-_____^
// | |
// | something about `foo`
// 3 |
// 4 | }
// | _^ test
for &(_, annotation) in &annotations_position {
let (underline, style) = if annotation.is_primary {
('^', Style::UnderlinePrimary)
} else {
('-', Style::UnderlineSecondary)
};
for p in annotation.start_col..annotation.end_col {
buffer.putc(line_offset + 1,
code_offset + p,
underline,
style);
}
}
annotations_position.iter().filter_map(|&(_, annotation)| {
match annotation.annotation_type {
AnnotationType::MultilineStart(p) | AnnotationType::MultilineEnd(p) => {
let style = if annotation.is_primary {
Style::LabelPrimary
} else {
Style::LabelSecondary
};
Some((p, style))
}
_ => None
}
}).collect::<Vec<_>>()
}
fn get_multispan_max_line_num(&mut self, msp: &MultiSpan) -> usize {
let mut max = 0;
if let Some(ref cm) = self.cm {
for primary_span in msp.primary_spans() {
if primary_span != &DUMMY_SP {
let hi = cm.lookup_char_pos(primary_span.hi());
if hi.line > max {
max = hi.line;
}
}
}
if !self.short_message {
for span_label in msp.span_labels() {
if span_label.span != DUMMY_SP {
let hi = cm.lookup_char_pos(span_label.span.hi());
if hi.line > max {
max = hi.line;
}
}
}
}
}
max
}
fn get_max_line_num(&mut self, span: &MultiSpan, children: &Vec<SubDiagnostic>) -> usize {
let mut max = 0;
let primary = self.get_multispan_max_line_num(span);
max = if primary > max { primary } else { max };
for sub in children {
let sub_result = self.get_multispan_max_line_num(&sub.span);
max = if sub_result > max { primary } else { max };
}
max
}
// This "fixes" MultiSpans that contain Spans that are pointing to locations inside of
// <*macros>. Since these locations are often difficult to read, we move these Spans from
// <*macros> to their corresponding use site.
fn fix_multispan_in_std_macros(&mut self,
span: &mut MultiSpan,
always_backtrace: bool) -> bool {
let mut spans_updated = false;
if let Some(ref cm) = self.cm {
let mut before_after: Vec<(Span, Span)> = vec![];
let mut new_labels: Vec<(Span, String)> = vec![];
// First, find all the spans in <*macros> and point instead at their use site
for sp in span.primary_spans() {
if *sp == DUMMY_SP {
continue;
}
let call_sp = cm.call_span_if_macro(*sp);
if call_sp != *sp && !always_backtrace {
before_after.push((*sp, call_sp));
}
let backtrace_len = sp.macro_backtrace().len();
for (i, trace) in sp.macro_backtrace().iter().rev().enumerate() {
// Only show macro locations that are local
// and display them like a span_note
if let Some(def_site) = trace.def_site_span {
if def_site == DUMMY_SP {
continue;
}
if always_backtrace {
new_labels.push((def_site,
format!("in this expansion of `{}`{}",
trace.macro_decl_name,
if backtrace_len > 2 {
// if backtrace_len == 1 it'll be pointed
// at by "in this macro invocation"
format!(" (#{})", i + 1)
} else {
"".to_string()
})));
}
// Check to make sure we're not in any <*macros>
if !cm.span_to_filename(def_site).is_macros() &&
!trace.macro_decl_name.starts_with("#[") ||
always_backtrace {
new_labels.push((trace.call_site,
format!("in this macro invocation{}",
if backtrace_len > 2 && always_backtrace {
// only specify order when the macro
// backtrace is multiple levels deep
format!(" (#{})", i + 1)
} else {
"".to_string()
})));
if !always_backtrace {
break;
}
}
}
}
}
for (label_span, label_text) in new_labels {
span.push_span_label(label_span, label_text);
}
for sp_label in span.span_labels() {
if sp_label.span == DUMMY_SP {
continue;
}
if cm.span_to_filename(sp_label.span.clone()).is_macros() &&
!always_backtrace
{
let v = sp_label.span.macro_backtrace();
if let Some(use_site) = v.last() {
before_after.push((sp_label.span.clone(), use_site.call_site.clone()));
}
}
}
// After we have them, make sure we replace these 'bad' def sites with their use sites
for (before, after) in before_after {
span.replace(before, after);
spans_updated = true;
}
}
spans_updated
}
// This does a small "fix" for multispans by looking to see if it can find any that
// point directly at <*macros>. Since these are often difficult to read, this
// will change the span to point at the use site.
fn fix_multispans_in_std_macros(&mut self,
span: &mut MultiSpan,
children: &mut Vec<SubDiagnostic>,
backtrace: bool) {
let mut spans_updated = self.fix_multispan_in_std_macros(span, backtrace);
for child in children.iter_mut() {
spans_updated |= self.fix_multispan_in_std_macros(&mut child.span, backtrace);
}
if spans_updated {
children.push(SubDiagnostic {
level: Level::Note,
message: vec![
("this error originates in a macro outside of the current crate \
(in Nightly builds, run with -Z external-macro-backtrace \
for more info)".to_string(),
Style::NoStyle),
],
span: MultiSpan::new(),
render_span: None,
});
}
}
/// Add a left margin to every line but the first, given a padding length and the label being
/// displayed, keeping the provided highlighting.
fn msg_to_buffer(&self,
buffer: &mut StyledBuffer,
msg: &[(String, Style)],
padding: usize,
label: &str,
override_style: Option<Style>) {
// The extra 5 ` ` is padding that's always needed to align to the `note: `:
//
// error: message
// --> file.rs:13:20
// |
// 13 | <CODE>
// | ^^^^
// |
// = note: multiline
// message
// ++^^^----xx
// | | | |
// | | | magic `2`
// | | length of label
// | magic `3`
// `max_line_num_len`
let padding = (0..padding + label.len() + 5)
.map(|_| " ")
.collect::<String>();
/// Return whether `style`, or the override if present and the style is `NoStyle`.
fn style_or_override(style: Style, override_style: Option<Style>) -> Style {
if let Some(o) = override_style {
if style == Style::NoStyle {
return o;
}
}
style
}
let mut line_number = 0;
// Provided the following diagnostic message:
//
// let msg = vec![
// ("
// ("highlighted multiline\nstring to\nsee how it ", Style::NoStyle),
// ("looks", Style::Highlight),
// ("with\nvery ", Style::NoStyle),
// ("weird", Style::Highlight),
// (" formats\n", Style::NoStyle),
// ("see?", Style::Highlight),
// ];
//
// the expected output on a note is (* surround the highlighted text)
//
// = note: highlighted multiline
// string to
// see how it *looks* with
// very *weird* formats
// see?
for &(ref text, ref style) in msg.iter() {
let lines = text.split('\n').collect::<Vec<_>>();
if lines.len() > 1 {
for (i, line) in lines.iter().enumerate() {
if i != 0 {
line_number += 1;
buffer.append(line_number, &padding, Style::NoStyle);
}
buffer.append(line_number, line, style_or_override(*style, override_style));
}
} else {
buffer.append(line_number, text, style_or_override(*style, override_style));
}
}
}
fn emit_message_default(&mut self,
msp: &MultiSpan,
msg: &Vec<(String, Style)>,
code: &Option<DiagnosticId>,
level: &Level,
max_line_num_len: usize,
is_secondary: bool)
-> io::Result<()> {
let mut buffer = StyledBuffer::new();
if msp.primary_spans().is_empty() && msp.span_labels().is_empty() && is_secondary
&& !self.short_message {
// This is a secondary message with no span info
for _ in 0..max_line_num_len {
buffer.prepend(0, " ", Style::NoStyle);
}
draw_note_separator(&mut buffer, 0, max_line_num_len + 1);
buffer.append(0, &level.to_string(), Style::HeaderMsg);
buffer.append(0, ": ", Style::NoStyle);
self.msg_to_buffer(&mut buffer, msg, max_line_num_len, "note", None);
} else {
buffer.append(0, &level.to_string(), Style::Level(level.clone()));
// only render error codes, not lint codes
if let Some(DiagnosticId::Error(ref code)) = *code {
buffer.append(0, "[", Style::Level(level.clone()));
buffer.append(0, &code, Style::Level(level.clone()));
buffer.append(0, "]", Style::Level(level.clone()));
}
buffer.append(0, ": ", Style::HeaderMsg);
for &(ref text, _) in msg.iter() {
buffer.append(0, text, Style::HeaderMsg);
}
}
// Preprocess all the annotations so that they are grouped by file and by line number
// This helps us quickly iterate over the whole message (including secondary file spans)
let mut annotated_files = self.preprocess_annotations(msp);
// Make sure our primary file comes first
let (primary_lo, cm) = if let (Some(cm), Some(ref primary_span)) =
(self.cm.as_ref(), msp.primary_span().as_ref()) {
if primary_span != &&DUMMY_SP {
(cm.lookup_char_pos(primary_span.lo()), cm)
} else {
emit_to_destination(&buffer.render(), level, &mut self.dst, self.short_message)?;
return Ok(());
}
} else {
// If we don't have span information, emit and exit
emit_to_destination(&buffer.render(), level, &mut self.dst, self.short_message)?;
return Ok(());
};
if let Ok(pos) =
annotated_files.binary_search_by(|x| x.file.name.cmp(&primary_lo.file.name)) {
annotated_files.swap(0, pos);
}
// Print out the annotate source lines that correspond with the error
for annotated_file in annotated_files {
// we can't annotate anything if the source is unavailable.
if !cm.ensure_filemap_source_present(annotated_file.file.clone()) {
continue;
}
// print out the span location and spacer before we print the annotated source
// to do this, we need to know if this span will be primary
let is_primary = primary_lo.file.name == annotated_file.file.name;
if is_primary {
let loc = primary_lo.clone();
if !self.short_message {
// remember where we are in the output buffer for easy reference
let buffer_msg_line_offset = buffer.num_lines();
buffer.prepend(buffer_msg_line_offset, "--> ", Style::LineNumber);
buffer.append(buffer_msg_line_offset,
&format!("{}:{}:{}",
loc.file.name,
cm.doctest_offset_line(loc.line),
loc.col.0 + 1),
Style::LineAndColumn);
for _ in 0..max_line_num_len {
buffer.prepend(buffer_msg_line_offset, " ", Style::NoStyle);
}
} else {
buffer.prepend(0,
&format!("{}:{}:{} - ",
loc.file.name,
cm.doctest_offset_line(loc.line),
loc.col.0 + 1),
Style::LineAndColumn);
}
} else if !self.short_message {
// remember where we are in the output buffer for easy reference
let buffer_msg_line_offset = buffer.num_lines();
// Add spacing line
draw_col_separator(&mut buffer, buffer_msg_line_offset, max_line_num_len + 1);
// Then, the secondary file indicator
buffer.prepend(buffer_msg_line_offset + 1, "::: ", Style::LineNumber);
buffer.append(buffer_msg_line_offset + 1,
&annotated_file.file.name.to_string(),
Style::LineAndColumn);
for _ in 0..max_line_num_len {
buffer.prepend(buffer_msg_line_offset + 1, " ", Style::NoStyle);
}
}
if !self.short_message {
// Put in the spacer between the location and annotated source
let buffer_msg_line_offset = buffer.num_lines();
draw_col_separator_no_space(&mut buffer,
buffer_msg_line_offset,
max_line_num_len + 1);
// Contains the vertical lines' positions for active multiline annotations
let mut multilines = HashMap::new();
// Next, output the annotate source for this file
for line_idx in 0..annotated_file.lines.len() {
let previous_buffer_line = buffer.num_lines();
let width_offset = 3 + max_line_num_len;
let code_offset = if annotated_file.multiline_depth == 0 {
width_offset
} else {
width_offset + annotated_file.multiline_depth + 1
};
let depths = self.render_source_line(&mut buffer,
annotated_file.file.clone(),
&annotated_file.lines[line_idx],
width_offset,
code_offset);
let mut to_add = HashMap::new();
for (depth, style) in depths {
if multilines.get(&depth).is_some() {
multilines.remove(&depth);
} else {
to_add.insert(depth, style);
}
}
// Set the multiline annotation vertical lines to the left of
// the code in this line.
for (depth, style) in &multilines {
for line in previous_buffer_line..buffer.num_lines() {
draw_multiline_line(&mut buffer,
line,
width_offset,
*depth,
*style);
}
}
// check to see if we need to print out or elide lines that come between
// this annotated line and the next one.
if line_idx < (annotated_file.lines.len() - 1) {
let line_idx_delta = annotated_file.lines[line_idx + 1].line_index -
annotated_file.lines[line_idx].line_index;
if line_idx_delta > 2 {
let last_buffer_line_num = buffer.num_lines();
buffer.puts(last_buffer_line_num, 0, "...", Style::LineNumber);
// Set the multiline annotation vertical lines on `...` bridging line.
for (depth, style) in &multilines {
draw_multiline_line(&mut buffer,
last_buffer_line_num,
width_offset,
*depth,
*style);
}
} else if line_idx_delta == 2 {
let unannotated_line = annotated_file.file
.get_line(annotated_file.lines[line_idx].line_index)
.unwrap_or_else(|| Cow::from(""));
let last_buffer_line_num = buffer.num_lines();
buffer.puts(last_buffer_line_num,
0,
&(annotated_file.lines[line_idx + 1].line_index - 1)
.to_string(),
Style::LineNumber);
draw_col_separator(&mut buffer,
last_buffer_line_num,
1 + max_line_num_len);
buffer.puts(last_buffer_line_num,
code_offset,
&unannotated_line,
Style::Quotation);
for (depth, style) in &multilines {
draw_multiline_line(&mut buffer,
last_buffer_line_num,
width_offset,
*depth,
*style);
}
}
}
multilines.extend(&to_add);
}
}
}
// final step: take our styled buffer, render it, then output it
emit_to_destination(&buffer.render(), level, &mut self.dst, self.short_message)?;
Ok(())
}
fn emit_suggestion_default(&mut self,
suggestion: &CodeSuggestion,
level: &Level,
max_line_num_len: usize)
-> io::Result<()> {
use std::borrow::Borrow;
if let Some(ref cm) = self.cm {
let mut buffer = StyledBuffer::new();
// Render the suggestion message
buffer.append(0, &level.to_string(), Style::Level(level.clone()));
buffer.append(0, ": ", Style::HeaderMsg);
self.msg_to_buffer(&mut buffer,
&[(suggestion.msg.to_owned(), Style::NoStyle)],
max_line_num_len,
"suggestion",
Some(Style::HeaderMsg));
// Render the replacements for each suggestion
let suggestions = suggestion.splice_lines(cm.borrow());
let mut row_num = 2;
for &(ref complete, ref parts) in suggestions.iter().take(MAX_SUGGESTIONS) {
let show_underline = parts.len() == 1
&& complete.lines().count() == 1
&& parts[0].snippet.trim() != complete.trim();
let lines = cm.span_to_lines(parts[0].span).unwrap();
assert!(!lines.lines.is_empty());
let span_start_pos = cm.lookup_char_pos(parts[0].span.lo());
let line_start = span_start_pos.line;
draw_col_separator_no_space(&mut buffer, 1, max_line_num_len + 1);
let mut line_pos = 0;
// Only show underline if there's a single suggestion and it is a single line
let mut lines = complete.lines();
for line in lines.by_ref().take(MAX_HIGHLIGHT_LINES) {
// Print the span column to avoid confusion
buffer.puts(row_num,
0,
&((line_start + line_pos).to_string()),
Style::LineNumber);
// print the suggestion
draw_col_separator(&mut buffer, row_num, max_line_num_len + 1);
buffer.append(row_num, line, Style::NoStyle);
line_pos += 1;
row_num += 1;
}
// Only show an underline in the suggestions if the suggestion is not the
// entirety of the code being shown and the displayed code is not multiline.
if show_underline {
draw_col_separator(&mut buffer, row_num, max_line_num_len + 1);
let start = parts[0].snippet.len() - parts[0].snippet.trim_left().len();
// account for substitutions containing unicode characters
let sub_len = parts[0].snippet.trim().chars().fold(0, |acc, ch| {
acc + unicode_width::UnicodeWidthChar::width(ch).unwrap_or(0)
});
let underline_start = span_start_pos.col_display + start;
let underline_end = span_start_pos.col_display + start + sub_len;
for p in underline_start..underline_end {
buffer.putc(row_num,
max_line_num_len + 3 + p,
'^',
Style::UnderlinePrimary);
}
row_num += 1;
}
// if we elided some lines, add an ellipsis
if let Some(_) = lines.next() {
buffer.puts(row_num, max_line_num_len - 1, "...", Style::LineNumber);
} else if !show_underline {
draw_col_separator_no_space(&mut buffer, row_num, max_line_num_len + 1);
row_num += 1;
}
}
if suggestions.len() > MAX_SUGGESTIONS {
let msg = format!("and {} other candidates", suggestions.len() - MAX_SUGGESTIONS);
buffer.puts(row_num, 0, &msg, Style::NoStyle);
}
emit_to_destination(&buffer.render(), level, &mut self.dst, self.short_message)?;
}
Ok(())
}
fn emit_messages_default(&mut self,
level: &Level,
message: &Vec<(String, Style)>,
code: &Option<DiagnosticId>,
span: &MultiSpan,
children: &Vec<SubDiagnostic>,
suggestions: &[CodeSuggestion]) {
let max_line_num = self.get_max_line_num(span, children);
let max_line_num_len = max_line_num.to_string().len();
match self.emit_message_default(span,
message,
code,
level,
max_line_num_len,
false) {
Ok(()) => {
if !children.is_empty() {
let mut buffer = StyledBuffer::new();
if !self.short_message {
draw_col_separator_no_space(&mut buffer, 0, max_line_num_len + 1);
}
match emit_to_destination(&buffer.render(), level, &mut self.dst,
self.short_message) {
Ok(()) => (),
Err(e) => panic!("failed to emit error: {}", e)
}
}
if !self.short_message {
for child in children {
let span = child.render_span.as_ref().unwrap_or(&child.span);
match self.emit_message_default(&span,
&child.styled_message(),
&None,
&child.level,
max_line_num_len,
true) {
Err(e) => panic!("failed to emit error: {}", e),
_ => ()
}
}
for sugg in suggestions {
match self.emit_suggestion_default(sugg,
&Level::Help,
max_line_num_len) {
Err(e) => panic!("failed to emit error: {}", e),
_ => ()
}
}
}
}
Err(e) => panic!("failed to emit error: {}", e),
}
match write!(&mut self.dst, "\n") {
Err(e) => panic!("failed to emit error: {}", e),
_ => {
match self.dst.flush() {
Err(e) => panic!("failed to emit error: {}", e),
_ => (),
}
}
}
}
}
fn draw_col_separator(buffer: &mut StyledBuffer, line: usize, col: usize) {
buffer.puts(line, col, "| ", Style::LineNumber);
}
fn draw_col_separator_no_space(buffer: &mut StyledBuffer, line: usize, col: usize) {
draw_col_separator_no_space_with_style(buffer, line, col, Style::LineNumber);
}
fn draw_col_separator_no_space_with_style(buffer: &mut StyledBuffer,
line: usize,
col: usize,
style: Style) {
buffer.putc(line, col, '|', style);
}
fn draw_range(buffer: &mut StyledBuffer, symbol: char, line: usize,
col_from: usize, col_to: usize, style: Style) {
for col in col_from..col_to {
buffer.putc(line, col, symbol, style);
}
}
fn draw_note_separator(buffer: &mut StyledBuffer, line: usize, col: usize) {
buffer.puts(line, col, "= ", Style::LineNumber);
}
fn draw_multiline_line(buffer: &mut StyledBuffer,
line: usize,
offset: usize,
depth: usize,
style: Style)
{
buffer.putc(line, offset + depth - 1, '|', style);
}
fn num_overlap(a_start: usize, a_end: usize, b_start: usize, b_end:usize, inclusive: bool) -> bool {
let extra = if inclusive {
1
} else {
0
};
(b_start..b_end + extra).contains(a_start) ||
(a_start..a_end + extra).contains(b_start)
}
fn overlaps(a1: &Annotation, a2: &Annotation, padding: usize) -> bool {
num_overlap(a1.start_col, a1.end_col + padding, a2.start_col, a2.end_col, false)
}
fn emit_to_destination(rendered_buffer: &Vec<Vec<StyledString>>,
lvl: &Level,
dst: &mut Destination,
short_message: bool)
-> io::Result<()> {
use lock;
// In order to prevent error message interleaving, where multiple error lines get intermixed
// when multiple compiler processes error simultaneously, we emit errors with additional
// steps.
//
// On Unix systems, we write into a buffered terminal rather than directly to a terminal. When
// the .flush() is called we take the buffer created from the buffered writes and write it at
// one shot. Because the Unix systems use ANSI for the colors, which is a text-based styling
// scheme, this buffered approach works and maintains the styling.
//
// On Windows, styling happens through calls to a terminal API. This prevents us from using the
// same buffering approach. Instead, we use a global Windows mutex, which we acquire long
// enough to output the full error message, then we release.
let _buffer_lock = lock::acquire_global_lock("rustc_errors");
for line in rendered_buffer {
for part in line {
dst.apply_style(lvl.clone(), part.style)?;
write!(dst, "{}", part.text)?;
dst.reset_attrs()?;
}
if !short_message {
write!(dst, "\n")?;
}
}
dst.flush()?;
Ok(())
}
#[cfg(unix)]
fn stderr_isatty() -> bool {
use libc;
unsafe { libc::isatty(libc::STDERR_FILENO) != 0 }
}
#[cfg(windows)]
fn stderr_isatty() -> bool {
type DWORD = u32;
type BOOL = i32;
type HANDLE = *mut u8;
const STD_ERROR_HANDLE: DWORD = -12i32 as DWORD;
extern "system" {
fn GetStdHandle(which: DWORD) -> HANDLE;
fn GetConsoleMode(hConsoleHandle: HANDLE, lpMode: *mut DWORD) -> BOOL;
}
unsafe {
let handle = GetStdHandle(STD_ERROR_HANDLE);
let mut out = 0;
GetConsoleMode(handle, &mut out) != 0
}
}
pub type BufferedStderr = term::Terminal<Output = BufferedWriter> + Send;
pub enum Destination {
Terminal(Box<term::StderrTerminal>),
BufferedTerminal(Box<BufferedStderr>),
Raw(Box<Write + Send>),
}
/// Buffered writer gives us a way on Unix to buffer up an entire error message before we output
/// it. This helps to prevent interleaving of multiple error messages when multiple compiler
/// processes error simultaneously
pub struct BufferedWriter {
buffer: Vec<u8>,
}
impl BufferedWriter {
// note: we use _new because the conditional compilation at its use site may make this
// this function unused on some platforms
fn _new() -> BufferedWriter {
BufferedWriter { buffer: vec![] }
}
}
impl Write for BufferedWriter {
fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
for b in buf {
self.buffer.push(*b);
}
Ok(buf.len())
}
fn flush(&mut self) -> io::Result<()> {
let mut stderr = io::stderr();
let result = stderr.write_all(&self.buffer)
.and_then(|_| stderr.flush());
self.buffer.clear();
result
}
}
impl Destination {
#[cfg(not(windows))]
/// When not on Windows, prefer the buffered terminal so that we can buffer an entire error
/// to be emitted at one time.
fn from_stderr() -> Destination {
let stderr: Option<Box<BufferedStderr>> =
term::TerminfoTerminal::new(BufferedWriter::_new())
.map(|t| Box::new(t) as Box<BufferedStderr>);
match stderr {
Some(t) => BufferedTerminal(t),
None => Raw(Box::new(io::stderr())),
}
}
#[cfg(windows)]
/// Return a normal, unbuffered terminal when on Windows.
fn from_stderr() -> Destination {
let stderr: Option<Box<term::StderrTerminal>> = term::TerminfoTerminal::new(io::stderr())
.map(|t| Box::new(t) as Box<term::StderrTerminal>)
.or_else(|| {
term::WinConsole::new(io::stderr())
.ok()
.map(|t| Box::new(t) as Box<term::StderrTerminal>)
});
match stderr {
Some(t) => Terminal(t),
None => Raw(Box::new(io::stderr())),
}
}
fn apply_style(&mut self, lvl: Level, style: Style) -> io::Result<()> {
match style {
Style::LineAndColumn => {}
Style::LineNumber => {
self.start_attr(term::Attr::Bold)?;
if cfg!(windows) {
self.start_attr(term::Attr::ForegroundColor(term::color::BRIGHT_CYAN))?;
} else {
self.start_attr(term::Attr::ForegroundColor(term::color::BRIGHT_BLUE))?;
}
}
Style::Quotation => {}
Style::OldSchoolNoteText | Style::HeaderMsg => {
self.start_attr(term::Attr::Bold)?;
if cfg!(windows) {
self.start_attr(term::Attr::ForegroundColor(term::color::BRIGHT_WHITE))?;
}
}
Style::UnderlinePrimary | Style::LabelPrimary => {
self.start_attr(term::Attr::Bold)?;
self.start_attr(term::Attr::ForegroundColor(lvl.color()))?;
}
Style::UnderlineSecondary |
Style::LabelSecondary => {
self.start_attr(term::Attr::Bold)?;
if cfg!(windows) {
self.start_attr(term::Attr::ForegroundColor(term::color::BRIGHT_CYAN))?;
} else {
self.start_attr(term::Attr::ForegroundColor(term::color::BRIGHT_BLUE))?;
}
}
Style::NoStyle => {}
Style::Level(l) => {
self.start_attr(term::Attr::Bold)?;
self.start_attr(term::Attr::ForegroundColor(l.color()))?;
}
Style::Highlight => self.start_attr(term::Attr::Bold)?,
}
Ok(())
}
fn start_attr(&mut self, attr: term::Attr) -> io::Result<()> {
match *self {
Terminal(ref mut t) => {
t.attr(attr)?;
}
BufferedTerminal(ref mut t) => {
t.attr(attr)?;
}
Raw(_) => {}
}
Ok(())
}
fn reset_attrs(&mut self) -> io::Result<()> {
match *self {
Terminal(ref mut t) => {
t.reset()?;
}
BufferedTerminal(ref mut t) => {
t.reset()?;
}
Raw(_) => {}
}
Ok(())
}
}
impl Write for Destination {
fn write(&mut self, bytes: &[u8]) -> io::Result<usize> {
match *self {
Terminal(ref mut t) => t.write(bytes),
BufferedTerminal(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(),
BufferedTerminal(ref mut t) => t.flush(),
Raw(ref mut w) => w.flush(),
}
}
}