//! Diagnostics creation and emission for `rustc`. //! //! This module contains the code for creating and emitting diagnostics. #![doc(html_root_url = "https://doc.rust-lang.org/nightly/")] #![feature(rustc_private, crate_visibility_modifier)] #![feature(nll)] pub use emitter::ColorConfig; use log::debug; use Level::*; use emitter::{is_case_difference, Emitter, EmitterWriter}; use registry::Registry; use rustc_data_structures::fx::{FxHashSet, FxIndexMap}; use rustc_data_structures::stable_hasher::StableHasher; use rustc_data_structures::sync::{self, Lock, Lrc}; use rustc_data_structures::AtomicRef; use rustc_span::source_map::SourceMap; use rustc_span::{Loc, MultiSpan, Span}; use std::borrow::Cow; use std::panic; use std::path::Path; use std::{error, fmt}; use termcolor::{Color, ColorSpec}; pub mod annotate_snippet_emitter_writer; mod diagnostic; mod diagnostic_builder; pub mod emitter; pub mod json; mod lock; pub mod registry; mod snippet; mod styled_buffer; pub use snippet::Style; pub type PResult<'a, T> = Result>; // `PResult` is used a lot. Make sure it doesn't unintentionally get bigger. // (See also the comment on `DiagnosticBuilderInner`.) #[cfg(target_arch = "x86_64")] rustc_data_structures::static_assert_size!(PResult<'_, bool>, 16); /// Indicates the confidence in the correctness of a suggestion. /// /// All suggestions are marked with an `Applicability`. Tools use the applicability of a suggestion /// to determine whether it should be automatically applied or if the user should be consulted /// before applying the suggestion. #[derive(Copy, Clone, Debug, PartialEq, Hash, RustcEncodable, RustcDecodable)] pub enum Applicability { /// The suggestion is definitely what the user intended. This suggestion should be /// automatically applied. MachineApplicable, /// The suggestion may be what the user intended, but it is uncertain. The suggestion should /// result in valid Rust code if it is applied. MaybeIncorrect, /// The suggestion contains placeholders like `(...)` or `{ /* fields */ }`. The suggestion /// cannot be applied automatically because it will not result in valid Rust code. The user /// will need to fill in the placeholders. HasPlaceholders, /// The applicability of the suggestion is unknown. Unspecified, } #[derive(Debug, PartialEq, Eq, Clone, Copy, Hash, RustcEncodable, RustcDecodable)] pub enum SuggestionStyle { /// Hide the suggested code when displaying this suggestion inline. HideCodeInline, /// Always hide the suggested code but display the message. HideCodeAlways, /// Do not display this suggestion in the cli output, it is only meant for tools. CompletelyHidden, /// Always show the suggested code. /// This will *not* show the code if the suggestion is inline *and* the suggested code is /// empty. ShowCode, /// Always show the suggested code independently. ShowAlways, } impl SuggestionStyle { fn hide_inline(&self) -> bool { match *self { SuggestionStyle::ShowCode => false, _ => true, } } } #[derive(Clone, Debug, PartialEq, Hash, RustcEncodable, RustcDecodable)] pub struct CodeSuggestion { /// Each substitute can have multiple variants due to multiple /// applicable suggestions /// /// `foo.bar` might be replaced with `a.b` or `x.y` by replacing /// `foo` and `bar` on their own: /// /// ``` /// vec![ /// Substitution { parts: vec![(0..3, "a"), (4..7, "b")] }, /// Substitution { parts: vec![(0..3, "x"), (4..7, "y")] }, /// ] /// ``` /// /// or by replacing the entire span: /// /// ``` /// vec![ /// Substitution { parts: vec![(0..7, "a.b")] }, /// Substitution { parts: vec![(0..7, "x.y")] }, /// ] /// ``` pub substitutions: Vec, pub msg: String, /// Visual representation of this suggestion. pub style: SuggestionStyle, /// Whether or not the suggestion is approximate /// /// Sometimes we may show suggestions with placeholders, /// which are useful for users but not useful for /// tools like rustfix pub applicability: Applicability, } #[derive(Clone, Debug, PartialEq, Hash, RustcEncodable, RustcDecodable)] /// See the docs on `CodeSuggestion::substitutions` pub struct Substitution { pub parts: Vec, } #[derive(Clone, Debug, PartialEq, Hash, RustcEncodable, RustcDecodable)] pub struct SubstitutionPart { pub span: Span, pub snippet: String, } impl CodeSuggestion { /// Returns the assembled code suggestions, whether they should be shown with an underline /// and whether the substitution only differs in capitalization. pub fn splice_lines(&self, sm: &SourceMap) -> Vec<(String, Vec, bool)> { use rustc_span::{CharPos, Pos}; fn push_trailing( buf: &mut String, line_opt: Option<&Cow<'_, str>>, lo: &Loc, hi_opt: Option<&Loc>, ) { let (lo, hi_opt) = (lo.col.to_usize(), hi_opt.map(|hi| hi.col.to_usize())); if let Some(line) = line_opt { if let Some(lo) = line.char_indices().map(|(i, _)| i).nth(lo) { let hi_opt = hi_opt.and_then(|hi| line.char_indices().map(|(i, _)| i).nth(hi)); match hi_opt { Some(hi) if hi > lo => buf.push_str(&line[lo..hi]), Some(_) => (), None => buf.push_str(&line[lo..]), } } if hi_opt.is_none() { buf.push('\n'); } } } assert!(!self.substitutions.is_empty()); self.substitutions .iter() .filter(|subst| { // Suggestions coming from macros can have malformed spans. This is a heavy // handed approach to avoid ICEs by ignoring the suggestion outright. let invalid = subst.parts.iter().any(|item| sm.is_valid_span(item.span).is_err()); if invalid { debug!("splice_lines: suggestion contains an invalid span: {:?}", subst); } !invalid }) .cloned() .filter_map(|mut substitution| { // Assumption: all spans are in the same file, and all spans // are disjoint. Sort in ascending order. substitution.parts.sort_by_key(|part| part.span.lo()); // Find the bounding span. let lo = substitution.parts.iter().map(|part| part.span.lo()).min()?; let hi = substitution.parts.iter().map(|part| part.span.hi()).max()?; let bounding_span = Span::with_root_ctxt(lo, hi); // The different spans might belong to different contexts, if so ignore suggestion. let lines = sm.span_to_lines(bounding_span).ok()?; assert!(!lines.lines.is_empty()); // We can't splice anything if the source is unavailable. if !sm.ensure_source_file_source_present(lines.file.clone()) { return None; } // To build up the result, we do this for each span: // - push the line segment trailing the previous span // (at the beginning a "phantom" span pointing at the start of the line) // - push lines between the previous and current span (if any) // - if the previous and current span are not on the same line // push the line segment leading up to the current span // - splice in the span substitution // // Finally push the trailing line segment of the last span let sf = &lines.file; let mut prev_hi = sm.lookup_char_pos(bounding_span.lo()); prev_hi.col = CharPos::from_usize(0); let mut prev_line = sf.get_line(lines.lines[0].line_index); let mut buf = String::new(); for part in &substitution.parts { let cur_lo = sm.lookup_char_pos(part.span.lo()); if prev_hi.line == cur_lo.line { push_trailing(&mut buf, prev_line.as_ref(), &prev_hi, Some(&cur_lo)); } else { push_trailing(&mut buf, prev_line.as_ref(), &prev_hi, None); // push lines between the previous and current span (if any) for idx in prev_hi.line..(cur_lo.line - 1) { if let Some(line) = sf.get_line(idx) { buf.push_str(line.as_ref()); buf.push('\n'); } } if let Some(cur_line) = sf.get_line(cur_lo.line - 1) { let end = std::cmp::min(cur_line.len(), cur_lo.col.to_usize()); buf.push_str(&cur_line[..end]); } } buf.push_str(&part.snippet); prev_hi = sm.lookup_char_pos(part.span.hi()); prev_line = sf.get_line(prev_hi.line - 1); } let only_capitalization = is_case_difference(sm, &buf, bounding_span); // if the replacement already ends with a newline, don't print the next line if !buf.ends_with('\n') { push_trailing(&mut buf, prev_line.as_ref(), &prev_hi, None); } // remove trailing newlines while buf.ends_with('\n') { buf.pop(); } Some((buf, substitution.parts, only_capitalization)) }) .collect() } } pub use rustc_span::fatal_error::{FatalError, FatalErrorMarker}; /// Signifies that the compiler died with an explicit call to `.bug` /// or `.span_bug` rather than a failed assertion, etc. #[derive(Copy, Clone, Debug)] pub struct ExplicitBug; impl fmt::Display for ExplicitBug { fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { write!(f, "parser internal bug") } } impl error::Error for ExplicitBug {} pub use diagnostic::{Diagnostic, DiagnosticId, DiagnosticStyledString, SubDiagnostic}; pub use diagnostic_builder::DiagnosticBuilder; /// A handler deals with errors and other compiler output. /// Certain errors (fatal, bug, unimpl) may cause immediate exit, /// others log errors for later reporting. pub struct Handler { flags: HandlerFlags, inner: Lock, } /// This inner struct exists to keep it all behind a single lock; /// this is done to prevent possible deadlocks in a multi-threaded compiler, /// as well as inconsistent state observation. struct HandlerInner { flags: HandlerFlags, /// The number of errors that have been emitted, including duplicates. /// /// This is not necessarily the count that's reported to the user once /// compilation ends. err_count: usize, deduplicated_err_count: usize, emitter: Box, delayed_span_bugs: Vec, /// This set contains the `DiagnosticId` of all emitted diagnostics to avoid /// emitting the same diagnostic with extended help (`--teach`) twice, which /// would be uneccessary repetition. taught_diagnostics: FxHashSet, /// Used to suggest rustc --explain emitted_diagnostic_codes: FxHashSet, /// This set contains a hash of every diagnostic that has been emitted by /// this handler. These hashes is used to avoid emitting the same error /// twice. emitted_diagnostics: FxHashSet, /// Stashed diagnostics emitted in one stage of the compiler that may be /// stolen by other stages (e.g. to improve them and add more information). /// The stashed diagnostics count towards the total error count. /// When `.abort_if_errors()` is called, these are also emitted. stashed_diagnostics: FxIndexMap<(Span, StashKey), Diagnostic>, } /// A key denoting where from a diagnostic was stashed. #[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash, Debug)] pub enum StashKey { ItemNoType, } fn default_track_diagnostic(_: &Diagnostic) {} pub static TRACK_DIAGNOSTICS: AtomicRef = AtomicRef::new(&(default_track_diagnostic as fn(&_))); #[derive(Copy, Clone, Default)] pub struct HandlerFlags { /// If false, warning-level lints are suppressed. /// (rustc: see `--allow warnings` and `--cap-lints`) pub can_emit_warnings: bool, /// If true, error-level diagnostics are upgraded to bug-level. /// (rustc: see `-Z treat-err-as-bug`) pub treat_err_as_bug: Option, /// If true, immediately emit diagnostics that would otherwise be buffered. /// (rustc: see `-Z dont-buffer-diagnostics` and `-Z treat-err-as-bug`) pub dont_buffer_diagnostics: bool, /// If true, immediately print bugs registered with `delay_span_bug`. /// (rustc: see `-Z report-delayed-bugs`) pub report_delayed_bugs: bool, /// Show macro backtraces. /// (rustc: see `-Z macro-backtrace`) pub macro_backtrace: bool, /// If true, identical diagnostics are reported only once. pub deduplicate_diagnostics: bool, } impl Drop for HandlerInner { fn drop(&mut self) { self.emit_stashed_diagnostics(); if !self.has_errors() { let bugs = std::mem::replace(&mut self.delayed_span_bugs, Vec::new()); let has_bugs = !bugs.is_empty(); for bug in bugs { self.emit_diagnostic(&bug); } if has_bugs { panic!("no errors encountered even though `delay_span_bug` issued"); } } } } impl Handler { pub fn with_tty_emitter( color_config: ColorConfig, can_emit_warnings: bool, treat_err_as_bug: Option, sm: Option>, ) -> Self { Self::with_tty_emitter_and_flags( color_config, sm, HandlerFlags { can_emit_warnings, treat_err_as_bug, ..Default::default() }, ) } pub fn with_tty_emitter_and_flags( color_config: ColorConfig, sm: Option>, flags: HandlerFlags, ) -> Self { let emitter = Box::new(EmitterWriter::stderr( color_config, sm, false, false, None, flags.macro_backtrace, )); Self::with_emitter_and_flags(emitter, flags) } pub fn with_emitter( can_emit_warnings: bool, treat_err_as_bug: Option, emitter: Box, ) -> Self { Handler::with_emitter_and_flags( emitter, HandlerFlags { can_emit_warnings, treat_err_as_bug, ..Default::default() }, ) } pub fn with_emitter_and_flags( emitter: Box, flags: HandlerFlags, ) -> Self { Self { flags, inner: Lock::new(HandlerInner { flags, err_count: 0, deduplicated_err_count: 0, emitter, delayed_span_bugs: Vec::new(), taught_diagnostics: Default::default(), emitted_diagnostic_codes: Default::default(), emitted_diagnostics: Default::default(), stashed_diagnostics: Default::default(), }), } } // This is here to not allow mutation of flags; // as of this writing it's only used in tests in librustc. pub fn can_emit_warnings(&self) -> bool { self.flags.can_emit_warnings } /// Resets the diagnostic error count as well as the cached emitted diagnostics. /// /// NOTE: *do not* call this function from rustc. It is only meant to be called from external /// tools that want to reuse a `Parser` cleaning the previously emitted diagnostics as well as /// the overall count of emitted error diagnostics. pub fn reset_err_count(&self) { let mut inner = self.inner.borrow_mut(); inner.err_count = 0; inner.deduplicated_err_count = 0; // actually free the underlying memory (which `clear` would not do) inner.delayed_span_bugs = Default::default(); inner.taught_diagnostics = Default::default(); inner.emitted_diagnostic_codes = Default::default(); inner.emitted_diagnostics = Default::default(); inner.stashed_diagnostics = Default::default(); } /// Stash a given diagnostic with the given `Span` and `StashKey` as the key for later stealing. pub fn stash_diagnostic(&self, span: Span, key: StashKey, diag: Diagnostic) { let mut inner = self.inner.borrow_mut(); // FIXME(Centril, #69537): Consider reintroducing panic on overwriting a stashed diagnostic // if/when we have a more robust macro-friendly replacement for `(span, key)` as a key. // See the PR for a discussion. inner.stashed_diagnostics.insert((span, key), diag); } /// Steal a previously stashed diagnostic with the given `Span` and `StashKey` as the key. pub fn steal_diagnostic(&self, span: Span, key: StashKey) -> Option> { self.inner .borrow_mut() .stashed_diagnostics .remove(&(span, key)) .map(|diag| DiagnosticBuilder::new_diagnostic(self, diag)) } /// Emit all stashed diagnostics. pub fn emit_stashed_diagnostics(&self) { self.inner.borrow_mut().emit_stashed_diagnostics(); } /// Construct a dummy builder with `Level::Cancelled`. /// /// Using this will neither report anything to the user (e.g. a warning), /// nor will compilation cancel as a result. pub fn struct_dummy(&self) -> DiagnosticBuilder<'_> { DiagnosticBuilder::new(self, Level::Cancelled, "") } /// Construct a builder at the `Warning` level at the given `span` and with the `msg`. pub fn struct_span_warn(&self, span: impl Into, msg: &str) -> DiagnosticBuilder<'_> { let mut result = self.struct_warn(msg); result.set_span(span); result } /// Construct a builder at the `Warning` level at the given `span` and with the `msg`. /// Also include a code. pub fn struct_span_warn_with_code( &self, span: impl Into, msg: &str, code: DiagnosticId, ) -> DiagnosticBuilder<'_> { let mut result = self.struct_span_warn(span, msg); result.code(code); result } /// Construct a builder at the `Warning` level with the `msg`. pub fn struct_warn(&self, msg: &str) -> DiagnosticBuilder<'_> { let mut result = DiagnosticBuilder::new(self, Level::Warning, msg); if !self.flags.can_emit_warnings { result.cancel(); } result } /// Construct a builder at the `Error` level at the given `span` and with the `msg`. pub fn struct_span_err(&self, span: impl Into, msg: &str) -> DiagnosticBuilder<'_> { let mut result = self.struct_err(msg); result.set_span(span); result } /// Construct a builder at the `Error` level at the given `span`, with the `msg`, and `code`. pub fn struct_span_err_with_code( &self, span: impl Into, msg: &str, code: DiagnosticId, ) -> DiagnosticBuilder<'_> { let mut result = self.struct_span_err(span, msg); result.code(code); result } /// Construct a builder at the `Error` level with the `msg`. // FIXME: This method should be removed (every error should have an associated error code). pub fn struct_err(&self, msg: &str) -> DiagnosticBuilder<'_> { DiagnosticBuilder::new(self, Level::Error, msg) } /// Construct a builder at the `Error` level with the `msg` and the `code`. pub fn struct_err_with_code(&self, msg: &str, code: DiagnosticId) -> DiagnosticBuilder<'_> { let mut result = self.struct_err(msg); result.code(code); result } /// Construct a builder at the `Fatal` level at the given `span` and with the `msg`. pub fn struct_span_fatal( &self, span: impl Into, msg: &str, ) -> DiagnosticBuilder<'_> { let mut result = self.struct_fatal(msg); result.set_span(span); result } /// Construct a builder at the `Fatal` level at the given `span`, with the `msg`, and `code`. pub fn struct_span_fatal_with_code( &self, span: impl Into, msg: &str, code: DiagnosticId, ) -> DiagnosticBuilder<'_> { let mut result = self.struct_span_fatal(span, msg); result.code(code); result } /// Construct a builder at the `Error` level with the `msg`. pub fn struct_fatal(&self, msg: &str) -> DiagnosticBuilder<'_> { DiagnosticBuilder::new(self, Level::Fatal, msg) } /// Construct a builder at the `Help` level with the `msg`. pub fn struct_help(&self, msg: &str) -> DiagnosticBuilder<'_> { DiagnosticBuilder::new(self, Level::Help, msg) } pub fn span_fatal(&self, span: impl Into, msg: &str) -> FatalError { self.emit_diag_at_span(Diagnostic::new(Fatal, msg), span); FatalError } pub fn span_fatal_with_code( &self, span: impl Into, msg: &str, code: DiagnosticId, ) -> FatalError { self.emit_diag_at_span(Diagnostic::new_with_code(Fatal, Some(code), msg), span); FatalError } pub fn span_err(&self, span: impl Into, msg: &str) { self.emit_diag_at_span(Diagnostic::new(Error, msg), span); } pub fn span_err_with_code(&self, span: impl Into, msg: &str, code: DiagnosticId) { self.emit_diag_at_span(Diagnostic::new_with_code(Error, Some(code), msg), span); } pub fn span_warn(&self, span: impl Into, msg: &str) { self.emit_diag_at_span(Diagnostic::new(Warning, msg), span); } pub fn span_warn_with_code(&self, span: impl Into, msg: &str, code: DiagnosticId) { self.emit_diag_at_span(Diagnostic::new_with_code(Warning, Some(code), msg), span); } pub fn span_bug(&self, span: impl Into, msg: &str) -> ! { self.inner.borrow_mut().span_bug(span, msg) } pub fn delay_span_bug(&self, span: impl Into, msg: &str) { self.inner.borrow_mut().delay_span_bug(span, msg) } pub fn span_bug_no_panic(&self, span: impl Into, msg: &str) { self.emit_diag_at_span(Diagnostic::new(Bug, msg), span); } pub fn span_note_without_error(&self, span: impl Into, msg: &str) { self.emit_diag_at_span(Diagnostic::new(Note, msg), span); } pub fn span_note_diag(&self, span: Span, msg: &str) -> DiagnosticBuilder<'_> { let mut db = DiagnosticBuilder::new(self, Note, msg); db.set_span(span); db } pub fn failure(&self, msg: &str) { self.inner.borrow_mut().failure(msg); } pub fn fatal(&self, msg: &str) -> FatalError { self.inner.borrow_mut().fatal(msg) } pub fn err(&self, msg: &str) { self.inner.borrow_mut().err(msg); } pub fn warn(&self, msg: &str) { let mut db = DiagnosticBuilder::new(self, Warning, msg); db.emit(); } pub fn note_without_error(&self, msg: &str) { DiagnosticBuilder::new(self, Note, msg).emit(); } pub fn bug(&self, msg: &str) -> ! { self.inner.borrow_mut().bug(msg) } pub fn err_count(&self) -> usize { self.inner.borrow().err_count() } pub fn has_errors(&self) -> bool { self.inner.borrow().has_errors() } pub fn has_errors_or_delayed_span_bugs(&self) -> bool { self.inner.borrow().has_errors_or_delayed_span_bugs() } pub fn print_error_count(&self, registry: &Registry) { self.inner.borrow_mut().print_error_count(registry) } pub fn abort_if_errors(&self) { self.inner.borrow_mut().abort_if_errors() } /// `true` if we haven't taught a diagnostic with this code already. /// The caller must then teach the user about such a diagnostic. /// /// Used to suppress emitting the same error multiple times with extended explanation when /// calling `-Zteach`. pub fn must_teach(&self, code: &DiagnosticId) -> bool { self.inner.borrow_mut().must_teach(code) } pub fn force_print_diagnostic(&self, db: Diagnostic) { self.inner.borrow_mut().force_print_diagnostic(db) } pub fn emit_diagnostic(&self, diagnostic: &Diagnostic) { self.inner.borrow_mut().emit_diagnostic(diagnostic) } fn emit_diag_at_span(&self, mut diag: Diagnostic, sp: impl Into) { let mut inner = self.inner.borrow_mut(); inner.emit_diagnostic(diag.set_span(sp)); } pub fn emit_artifact_notification(&self, path: &Path, artifact_type: &str) { self.inner.borrow_mut().emit_artifact_notification(path, artifact_type) } pub fn delay_as_bug(&self, diagnostic: Diagnostic) { self.inner.borrow_mut().delay_as_bug(diagnostic) } } impl HandlerInner { fn must_teach(&mut self, code: &DiagnosticId) -> bool { self.taught_diagnostics.insert(code.clone()) } fn force_print_diagnostic(&mut self, db: Diagnostic) { self.emitter.emit_diagnostic(&db); } /// Emit all stashed diagnostics. fn emit_stashed_diagnostics(&mut self) { let diags = self.stashed_diagnostics.drain(..).map(|x| x.1).collect::>(); diags.iter().for_each(|diag| self.emit_diagnostic(diag)); } fn emit_diagnostic(&mut self, diagnostic: &Diagnostic) { if diagnostic.cancelled() { return; } if diagnostic.level == Warning && !self.flags.can_emit_warnings { return; } (*TRACK_DIAGNOSTICS)(diagnostic); if let Some(ref code) = diagnostic.code { self.emitted_diagnostic_codes.insert(code.clone()); } let already_emitted = |this: &mut Self| { use std::hash::Hash; let mut hasher = StableHasher::new(); diagnostic.hash(&mut hasher); let diagnostic_hash = hasher.finish(); !this.emitted_diagnostics.insert(diagnostic_hash) }; // Only emit the diagnostic if we've been asked to deduplicate and // haven't already emitted an equivalent diagnostic. if !(self.flags.deduplicate_diagnostics && already_emitted(self)) { self.emitter.emit_diagnostic(diagnostic); if diagnostic.is_error() { self.deduplicated_err_count += 1; } } if diagnostic.is_error() { self.bump_err_count(); } } fn emit_artifact_notification(&mut self, path: &Path, artifact_type: &str) { self.emitter.emit_artifact_notification(path, artifact_type); } fn treat_err_as_bug(&self) -> bool { self.flags.treat_err_as_bug.map(|c| self.err_count() >= c).unwrap_or(false) } fn print_error_count(&mut self, registry: &Registry) { self.emit_stashed_diagnostics(); let s = match self.deduplicated_err_count { 0 => return, 1 => "aborting due to previous error".to_string(), count => format!("aborting due to {} previous errors", count), }; if self.treat_err_as_bug() { return; } let _ = self.fatal(&s); let can_show_explain = self.emitter.should_show_explain(); let are_there_diagnostics = !self.emitted_diagnostic_codes.is_empty(); if can_show_explain && are_there_diagnostics { let mut error_codes = self .emitted_diagnostic_codes .iter() .filter_map(|x| match &x { DiagnosticId::Error(s) => { if let Ok(Some(_explanation)) = registry.try_find_description(s) { Some(s.clone()) } else { None } } _ => None, }) .collect::>(); if !error_codes.is_empty() { error_codes.sort(); if error_codes.len() > 1 { let limit = if error_codes.len() > 9 { 9 } else { error_codes.len() }; self.failure(&format!( "Some errors have detailed explanations: {}{}", error_codes[..limit].join(", "), if error_codes.len() > 9 { "..." } else { "." } )); self.failure(&format!( "For more information about an error, try \ `rustc --explain {}`.", &error_codes[0] )); } else { self.failure(&format!( "For more information about this error, try \ `rustc --explain {}`.", &error_codes[0] )); } } } } fn err_count(&self) -> usize { self.err_count + self.stashed_diagnostics.len() } fn has_errors(&self) -> bool { self.err_count() > 0 } fn has_errors_or_delayed_span_bugs(&self) -> bool { self.has_errors() || !self.delayed_span_bugs.is_empty() } fn abort_if_errors(&mut self) { self.emit_stashed_diagnostics(); if self.has_errors() { FatalError.raise(); } } fn span_bug(&mut self, sp: impl Into, msg: &str) -> ! { self.emit_diag_at_span(Diagnostic::new(Bug, msg), sp); panic!(ExplicitBug); } fn emit_diag_at_span(&mut self, mut diag: Diagnostic, sp: impl Into) { self.emit_diagnostic(diag.set_span(sp)); } fn delay_span_bug(&mut self, sp: impl Into, msg: &str) { if self.treat_err_as_bug() { // FIXME: don't abort here if report_delayed_bugs is off self.span_bug(sp, msg); } let mut diagnostic = Diagnostic::new(Level::Bug, msg); diagnostic.set_span(sp.into()); self.delay_as_bug(diagnostic) } fn failure(&mut self, msg: &str) { self.emit_diagnostic(&Diagnostic::new(FailureNote, msg)); } fn fatal(&mut self, msg: &str) -> FatalError { self.emit_error(Fatal, msg); FatalError } fn err(&mut self, msg: &str) { self.emit_error(Error, msg); } /// Emit an error; level should be `Error` or `Fatal`. fn emit_error(&mut self, level: Level, msg: &str) { if self.treat_err_as_bug() { self.bug(msg); } self.emit_diagnostic(&Diagnostic::new(level, msg)); } fn bug(&mut self, msg: &str) -> ! { self.emit_diagnostic(&Diagnostic::new(Bug, msg)); panic!(ExplicitBug); } fn delay_as_bug(&mut self, diagnostic: Diagnostic) { if self.flags.report_delayed_bugs { self.emit_diagnostic(&diagnostic); } self.delayed_span_bugs.push(diagnostic); } fn bump_err_count(&mut self) { self.err_count += 1; self.panic_if_treat_err_as_bug(); } fn panic_if_treat_err_as_bug(&self) { if self.treat_err_as_bug() { let s = match (self.err_count(), self.flags.treat_err_as_bug.unwrap_or(0)) { (0, _) => return, (1, 1) => "aborting due to `-Z treat-err-as-bug=1`".to_string(), (1, _) => return, (count, as_bug) => format!( "aborting after {} errors due to `-Z treat-err-as-bug={}`", count, as_bug, ), }; panic!(s); } } } #[derive(Copy, PartialEq, Clone, Hash, Debug, RustcEncodable, RustcDecodable)] pub enum Level { Bug, Fatal, Error, Warning, Note, Help, Cancelled, FailureNote, } impl fmt::Display for Level { fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { self.to_str().fmt(f) } } impl Level { fn color(self) -> ColorSpec { let mut spec = ColorSpec::new(); match self { Bug | Fatal | Error => { spec.set_fg(Some(Color::Red)).set_intense(true); } Warning => { spec.set_fg(Some(Color::Yellow)).set_intense(cfg!(windows)); } Note => { spec.set_fg(Some(Color::Green)).set_intense(true); } Help => { spec.set_fg(Some(Color::Cyan)).set_intense(true); } FailureNote => {} Cancelled => unreachable!(), } spec } pub fn to_str(self) -> &'static str { match self { Bug => "error: internal compiler error", Fatal | Error => "error", Warning => "warning", Note => "note", Help => "help", FailureNote => "failure-note", Cancelled => panic!("Shouldn't call on cancelled error"), } } pub fn is_failure_note(&self) -> bool { match *self { FailureNote => true, _ => false, } } } #[macro_export] macro_rules! pluralize { ($x:expr) => { if $x != 1 { "s" } else { "" } }; } // Useful type to use with `Result<>` indicate that an error has already // been reported to the user, so no need to continue checking. #[derive(Clone, Copy, Debug, RustcEncodable, RustcDecodable, Hash, PartialEq, Eq)] pub struct ErrorReported; rustc_data_structures::impl_stable_hash_via_hash!(ErrorReported);