compiler/rustc_errors/src/diagnostic.rs

   1 use crate::snippet::Style;
   2 use crate::CodeSuggestion;
   3 use crate::Level;
   4 use crate::Substitution;
   5 use crate::SubstitutionPart;
   6 use crate::SuggestionStyle;
   7 use crate::ToolMetadata;
   8 use rustc_data_structures::stable_map::FxHashMap;
   9 use rustc_lint_defs::{Applicability, LintExpectationId};
  10 use rustc_serialize::json::Json;
  11 use rustc_span::edition::LATEST_STABLE_EDITION;
  12 use rustc_span::{MultiSpan, Span, DUMMY_SP};
  13 use std::fmt;
  14 use std::hash::{Hash, Hasher};
  15
  16 /// Error type for `Diagnostic`'s `suggestions` field, indicating that
  17 /// `.disable_suggestions()` was called on the `Diagnostic`.
  18 #[derive(Clone, Debug, PartialEq, Eq, Hash, Encodable, Decodable)]
  19 pub struct SuggestionsDisabled;
  20
  21 #[must_use]
  22 #[derive(Clone, Debug, Encodable, Decodable)]
  23 pub struct Diagnostic {
  24     // NOTE(eddyb) this is private to disallow arbitrary after-the-fact changes,
  25     // outside of what methods in this crate themselves allow.
  26     crate level: Level,
  27
  28     pub message: Vec<(String, Style)>,
  29     pub code: Option<DiagnosticId>,
  30     pub span: MultiSpan,
  31     pub children: Vec<SubDiagnostic>,
  32     pub suggestions: Result<Vec<CodeSuggestion>, SuggestionsDisabled>,
  33
  34     /// This is not used for highlighting or rendering any error message.  Rather, it can be used
  35     /// as a sort key to sort a buffer of diagnostics.  By default, it is the primary span of
  36     /// `span` if there is one.  Otherwise, it is `DUMMY_SP`.
  37     pub sort_span: Span,
  38
  39     /// If diagnostic is from Lint, custom hash function ignores notes
  40     /// otherwise hash is based on the all the fields
  41     pub is_lint: bool,
  42 }
  43
  44 #[derive(Clone, Debug, PartialEq, Eq, Hash, Encodable, Decodable)]
  45 pub enum DiagnosticId {
  46     Error(String),
  47     Lint { name: String, has_future_breakage: bool, is_force_warn: bool },
  48 }
  49
  50 /// A "sub"-diagnostic attached to a parent diagnostic.
  51 /// For example, a note attached to an error.
  52 #[derive(Clone, Debug, PartialEq, Hash, Encodable, Decodable)]
  53 pub struct SubDiagnostic {
  54     pub level: Level,
  55     pub message: Vec<(String, Style)>,
  56     pub span: MultiSpan,
  57     pub render_span: Option<MultiSpan>,
  58 }
  59
  60 #[derive(Debug, PartialEq, Eq)]
  61 pub struct DiagnosticStyledString(pub Vec<StringPart>);
  62
  63 impl DiagnosticStyledString {
  64     pub fn new() -> DiagnosticStyledString {
  65         DiagnosticStyledString(vec![])
  66     }
  67     pub fn push_normal<S: Into<String>>(&mut self, t: S) {
  68         self.0.push(StringPart::Normal(t.into()));
  69     }
  70     pub fn push_highlighted<S: Into<String>>(&mut self, t: S) {
  71         self.0.push(StringPart::Highlighted(t.into()));
  72     }
  73     pub fn push<S: Into<String>>(&mut self, t: S, highlight: bool) {
  74         if highlight {
  75             self.push_highlighted(t);
  76         } else {
  77             self.push_normal(t);
  78         }
  79     }
  80     pub fn normal<S: Into<String>>(t: S) -> DiagnosticStyledString {
  81         DiagnosticStyledString(vec![StringPart::Normal(t.into())])
  82     }
  83
  84     pub fn highlighted<S: Into<String>>(t: S) -> DiagnosticStyledString {
  85         DiagnosticStyledString(vec![StringPart::Highlighted(t.into())])
  86     }
  87
  88     pub fn content(&self) -> String {
  89         self.0.iter().map(|x| x.content()).collect::<String>()
  90     }
  91 }
  92
  93 #[derive(Debug, PartialEq, Eq)]
  94 pub enum StringPart {
  95     Normal(String),
  96     Highlighted(String),
  97 }
  98
  99 impl StringPart {
 100     pub fn content(&self) -> &str {
 101         match self {
 102             &StringPart::Normal(ref s) | &StringPart::Highlighted(ref s) => s,
 103         }
 104     }
 105 }
 106
 107 impl Diagnostic {
 108     pub fn new(level: Level, message: &str) -> Self {
 109         Diagnostic::new_with_code(level, None, message)
 110     }
 111
 112     pub fn new_with_code(level: Level, code: Option<DiagnosticId>, message: &str) -> Self {
 113         Diagnostic {
 114             level,
 115             message: vec![(message.to_owned(), Style::NoStyle)],
 116             code,
 117             span: MultiSpan::new(),
 118             children: vec![],
 119             suggestions: Ok(vec![]),
 120             sort_span: DUMMY_SP,
 121             is_lint: false,
 122         }
 123     }
 124
 125     #[inline(always)]
 126     pub fn level(&self) -> Level {
 127         self.level
 128     }
 129
 130     pub fn is_error(&self) -> bool {
 131         match self.level {
 132             Level::Bug
 133             | Level::DelayedBug
 134             | Level::Fatal
 135             | Level::Error { .. }
 136             | Level::FailureNote => true,
 137
 138             Level::Warning
 139             | Level::Note
 140             | Level::OnceNote
 141             | Level::Help
 142             | Level::Allow
 143             | Level::Expect(_) => false,
 144         }
 145     }
 146
 147     pub fn update_unstable_expectation_id(
 148         &mut self,
 149         unstable_to_stable: &FxHashMap<LintExpectationId, LintExpectationId>,
 150     ) {
 151         if let Level::Expect(expectation_id) = &mut self.level {
 152             if expectation_id.is_stable() {
 153                 return;
 154             }
 155
 156             // The unstable to stable map only maps the unstable `AttrId` to a stable `HirId` with an attribute index.
 157             // The lint index inside the attribute is manually transferred here.
 158             let lint_index = expectation_id.get_lint_index();
 159             expectation_id.set_lint_index(None);
 160             let mut stable_id = *unstable_to_stable
 161                 .get(&expectation_id)
 162                 .expect("each unstable `LintExpectationId` must have a matching stable id");
 163
 164             stable_id.set_lint_index(lint_index);
 165             *expectation_id = stable_id;
 166         }
 167     }
 168
 169     pub fn has_future_breakage(&self) -> bool {
 170         match self.code {
 171             Some(DiagnosticId::Lint { has_future_breakage, .. }) => has_future_breakage,
 172             _ => false,
 173         }
 174     }
 175
 176     pub fn is_force_warn(&self) -> bool {
 177         match self.code {
 178             Some(DiagnosticId::Lint { is_force_warn, .. }) => is_force_warn,
 179             _ => false,
 180         }
 181     }
 182
 183     /// Delay emission of this diagnostic as a bug.
 184     ///
 185     /// This can be useful in contexts where an error indicates a bug but
 186     /// typically this only happens when other compilation errors have already
 187     /// happened. In those cases this can be used to defer emission of this
 188     /// diagnostic as a bug in the compiler only if no other errors have been
 189     /// emitted.
 190     ///
 191     /// In the meantime, though, callsites are required to deal with the "bug"
 192     /// locally in whichever way makes the most sense.
 193     #[track_caller]
 194     pub fn downgrade_to_delayed_bug(&mut self) -> &mut Self {
 195         assert!(
 196             self.is_error(),
 197             "downgrade_to_delayed_bug: cannot downgrade {:?} to DelayedBug: not an error",
 198             self.level
 199         );
 200         self.level = Level::DelayedBug;
 201
 202         self
 203     }
 204
 205     /// Adds a span/label to be included in the resulting snippet.
 206     ///
 207     /// This is pushed onto the [`MultiSpan`] that was created when the diagnostic
 208     /// was first built. That means it will be shown together with the original
 209     /// span/label, *not* a span added by one of the `span_{note,warn,help,suggestions}` methods.
 210     ///
 211     /// This span is *not* considered a ["primary span"][`MultiSpan`]; only
 212     /// the `Span` supplied when creating the diagnostic is primary.
 213     pub fn span_label<T: Into<String>>(&mut self, span: Span, label: T) -> &mut Self {
 214         self.span.push_span_label(span, label.into());
 215         self
 216     }
 217
 218     /// Labels all the given spans with the provided label.
 219     /// See [`Self::span_label()`] for more information.
 220     pub fn span_labels(
 221         &mut self,
 222         spans: impl IntoIterator<Item = Span>,
 223         label: impl AsRef<str>,
 224     ) -> &mut Self {
 225         let label = label.as_ref();
 226         for span in spans {
 227             self.span_label(span, label);
 228         }
 229         self
 230     }
 231
 232     pub fn replace_span_with(&mut self, after: Span) -> &mut Self {
 233         let before = self.span.clone();
 234         self.set_span(after);
 235         for span_label in before.span_labels() {
 236             if let Some(label) = span_label.label {
 237                 self.span_label(after, label);
 238             }
 239         }
 240         self
 241     }
 242
 243     pub fn note_expected_found(
 244         &mut self,
 245         expected_label: &dyn fmt::Display,
 246         expected: DiagnosticStyledString,
 247         found_label: &dyn fmt::Display,
 248         found: DiagnosticStyledString,
 249     ) -> &mut Self {
 250         self.note_expected_found_extra(expected_label, expected, found_label, found, &"", &"")
 251     }
 252
 253     pub fn note_unsuccessful_coercion(
 254         &mut self,
 255         expected: DiagnosticStyledString,
 256         found: DiagnosticStyledString,
 257     ) -> &mut Self {
 258         let mut msg: Vec<_> =
 259             vec![("required when trying to coerce from type `".to_string(), Style::NoStyle)];
 260         msg.extend(expected.0.iter().map(|x| match *x {
 261             StringPart::Normal(ref s) => (s.to_owned(), Style::NoStyle),
 262             StringPart::Highlighted(ref s) => (s.to_owned(), Style::Highlight),
 263         }));
 264         msg.push(("` to type '".to_string(), Style::NoStyle));
 265         msg.extend(found.0.iter().map(|x| match *x {
 266             StringPart::Normal(ref s) => (s.to_owned(), Style::NoStyle),
 267             StringPart::Highlighted(ref s) => (s.to_owned(), Style::Highlight),
 268         }));
 269         msg.push(("`".to_string(), Style::NoStyle));
 270
 271         // For now, just attach these as notes
 272         self.highlighted_note(msg);
 273         self
 274     }
 275
 276     pub fn note_expected_found_extra(
 277         &mut self,
 278         expected_label: &dyn fmt::Display,
 279         expected: DiagnosticStyledString,
 280         found_label: &dyn fmt::Display,
 281         found: DiagnosticStyledString,
 282         expected_extra: &dyn fmt::Display,
 283         found_extra: &dyn fmt::Display,
 284     ) -> &mut Self {
 285         let expected_label = expected_label.to_string();
 286         let expected_label = if expected_label.is_empty() {
 287             "expected".to_string()
 288         } else {
 289             format!("expected {}", expected_label)
 290         };
 291         let found_label = found_label.to_string();
 292         let found_label = if found_label.is_empty() {
 293             "found".to_string()
 294         } else {
 295             format!("found {}", found_label)
 296         };
 297         let (found_padding, expected_padding) = if expected_label.len() > found_label.len() {
 298             (expected_label.len() - found_label.len(), 0)
 299         } else {
 300             (0, found_label.len() - expected_label.len())
 301         };
 302         let mut msg: Vec<_> =
 303             vec![(format!("{}{} `", " ".repeat(expected_padding), expected_label), Style::NoStyle)];
 304         msg.extend(expected.0.iter().map(|x| match *x {
 305             StringPart::Normal(ref s) => (s.to_owned(), Style::NoStyle),
 306             StringPart::Highlighted(ref s) => (s.to_owned(), Style::Highlight),
 307         }));
 308         msg.push((format!("`{}\n", expected_extra), Style::NoStyle));
 309         msg.push((format!("{}{} `", " ".repeat(found_padding), found_label), Style::NoStyle));
 310         msg.extend(found.0.iter().map(|x| match *x {
 311             StringPart::Normal(ref s) => (s.to_owned(), Style::NoStyle),
 312             StringPart::Highlighted(ref s) => (s.to_owned(), Style::Highlight),
 313         }));
 314         msg.push((format!("`{}", found_extra), Style::NoStyle));
 315
 316         // For now, just attach these as notes.
 317         self.highlighted_note(msg);
 318         self
 319     }
 320
 321     pub fn note_trait_signature(&mut self, name: String, signature: String) -> &mut Self {
 322         self.highlighted_note(vec![
 323             (format!("`{}` from trait: `", name), Style::NoStyle),
 324             (signature, Style::Highlight),
 325             ("`".to_string(), Style::NoStyle),
 326         ]);
 327         self
 328     }
 329
 330     /// Add a note attached to this diagnostic.
 331     pub fn note(&mut self, msg: &str) -> &mut Self {
 332         self.sub(Level::Note, msg, MultiSpan::new(), None);
 333         self
 334     }
 335
 336     pub fn highlighted_note(&mut self, msg: Vec<(String, Style)>) -> &mut Self {
 337         self.sub_with_highlights(Level::Note, msg, MultiSpan::new(), None);
 338         self
 339     }
 340
 341     /// Prints the span with a note above it.
 342     /// This is like [`Diagnostic::note()`], but it gets its own span.
 343     pub fn note_once(&mut self, msg: &str) -> &mut Self {
 344         self.sub(Level::OnceNote, msg, MultiSpan::new(), None);
 345         self
 346     }
 347
 348     /// Prints the span with a note above it.
 349     /// This is like [`Diagnostic::note()`], but it gets its own span.
 350     pub fn span_note<S: Into<MultiSpan>>(&mut self, sp: S, msg: &str) -> &mut Self {
 351         self.sub(Level::Note, msg, sp.into(), None);
 352         self
 353     }
 354
 355     /// Prints the span with a note above it.
 356     /// This is like [`Diagnostic::note()`], but it gets its own span.
 357     pub fn span_note_once<S: Into<MultiSpan>>(&mut self, sp: S, msg: &str) -> &mut Self {
 358         self.sub(Level::OnceNote, msg, sp.into(), None);
 359         self
 360     }
 361
 362     /// Add a warning attached to this diagnostic.
 363     pub fn warn(&mut self, msg: &str) -> &mut Self {
 364         self.sub(Level::Warning, msg, MultiSpan::new(), None);
 365         self
 366     }
 367
 368     /// Prints the span with a warning above it.
 369     /// This is like [`Diagnostic::warn()`], but it gets its own span.
 370     pub fn span_warn<S: Into<MultiSpan>>(&mut self, sp: S, msg: &str) -> &mut Self {
 371         self.sub(Level::Warning, msg, sp.into(), None);
 372         self
 373     }
 374
 375     /// Add a help message attached to this diagnostic.
 376     pub fn help(&mut self, msg: &str) -> &mut Self {
 377         self.sub(Level::Help, msg, MultiSpan::new(), None);
 378         self
 379     }
 380
 381     /// Prints the span with some help above it.
 382     /// This is like [`Diagnostic::help()`], but it gets its own span.
 383     pub fn span_help<S: Into<MultiSpan>>(&mut self, sp: S, msg: &str) -> &mut Self {
 384         self.sub(Level::Help, msg, sp.into(), None);
 385         self
 386     }
 387
 388     /// Help the user upgrade to the latest edition.
 389     /// This is factored out to make sure it does the right thing with `Cargo.toml`.
 390     pub fn help_use_latest_edition(&mut self) -> &mut Self {
 391         if std::env::var_os("CARGO").is_some() {
 392             self.help(&format!("set `edition = \"{}\"` in `Cargo.toml`", LATEST_STABLE_EDITION));
 393         } else {
 394             self.help(&format!("pass `--edition {}` to `rustc`", LATEST_STABLE_EDITION));
 395         }
 396         self.note("for more on editions, read https://doc.rust-lang.org/edition-guide");
 397         self
 398     }
 399
 400     /// Disallow attaching suggestions this diagnostic.
 401     /// Any suggestions attached e.g. with the `span_suggestion_*` methods
 402     /// (before and after the call to `disable_suggestions`) will be ignored.
 403     pub fn disable_suggestions(&mut self) -> &mut Self {
 404         self.suggestions = Err(SuggestionsDisabled);
 405         self
 406     }
 407
 408     /// Helper for pushing to `self.suggestions`, if available (not disable).
 409     fn push_suggestion(&mut self, suggestion: CodeSuggestion) {
 410         if let Ok(suggestions) = &mut self.suggestions {
 411             suggestions.push(suggestion);
 412         }
 413     }
 414
 415     /// Show a suggestion that has multiple parts to it.
 416     /// In other words, multiple changes need to be applied as part of this suggestion.
 417     pub fn multipart_suggestion(
 418         &mut self,
 419         msg: &str,
 420         suggestion: Vec<(Span, String)>,
 421         applicability: Applicability,
 422     ) -> &mut Self {
 423         self.multipart_suggestion_with_style(
 424             msg,
 425             suggestion,
 426             applicability,
 427             SuggestionStyle::ShowCode,
 428         )
 429     }
 430
 431     /// Show a suggestion that has multiple parts to it, always as it's own subdiagnostic.
 432     /// In other words, multiple changes need to be applied as part of this suggestion.
 433     pub fn multipart_suggestion_verbose(
 434         &mut self,
 435         msg: &str,
 436         suggestion: Vec<(Span, String)>,
 437         applicability: Applicability,
 438     ) -> &mut Self {
 439         self.multipart_suggestion_with_style(
 440             msg,
 441             suggestion,
 442             applicability,
 443             SuggestionStyle::ShowAlways,
 444         )
 445     }
 446     /// [`Diagnostic::multipart_suggestion()`] but you can set the [`SuggestionStyle`].
 447     pub fn multipart_suggestion_with_style(
 448         &mut self,
 449         msg: &str,
 450         suggestion: Vec<(Span, String)>,
 451         applicability: Applicability,
 452         style: SuggestionStyle,
 453     ) -> &mut Self {
 454         assert!(!suggestion.is_empty());
 455         self.push_suggestion(CodeSuggestion {
 456             substitutions: vec![Substitution {
 457                 parts: suggestion
 458                     .into_iter()
 459                     .map(|(span, snippet)| SubstitutionPart { snippet, span })
 460                     .collect(),
 461             }],
 462             msg: msg.to_owned(),
 463             style,
 464             applicability,
 465             tool_metadata: Default::default(),
 466         });
 467         self
 468     }
 469
 470     /// Prints out a message with for a multipart suggestion without showing the suggested code.
 471     ///
 472     /// This is intended to be used for suggestions that are obvious in what the changes need to
 473     /// be from the message, showing the span label inline would be visually unpleasant
 474     /// (marginally overlapping spans or multiline spans) and showing the snippet window wouldn't
 475     /// improve understandability.
 476     pub fn tool_only_multipart_suggestion(
 477         &mut self,
 478         msg: &str,
 479         suggestion: Vec<(Span, String)>,
 480         applicability: Applicability,
 481     ) -> &mut Self {
 482         assert!(!suggestion.is_empty());
 483         self.push_suggestion(CodeSuggestion {
 484             substitutions: vec![Substitution {
 485                 parts: suggestion
 486                     .into_iter()
 487                     .map(|(span, snippet)| SubstitutionPart { snippet, span })
 488                     .collect(),
 489             }],
 490             msg: msg.to_owned(),
 491             style: SuggestionStyle::CompletelyHidden,
 492             applicability,
 493             tool_metadata: Default::default(),
 494         });
 495         self
 496     }
 497
 498     /// Prints out a message with a suggested edit of the code.
 499     ///
 500     /// In case of short messages and a simple suggestion, rustc displays it as a label:
 501     ///
 502     /// ```text
 503     /// try adding parentheses: `(tup.0).1`
 504     /// ```
 505     ///
 506     /// The message
 507     ///
 508     /// * should not end in any punctuation (a `:` is added automatically)
 509     /// * should not be a question (avoid language like "did you mean")
 510     /// * should not contain any phrases like "the following", "as shown", etc.
 511     /// * may look like "to do xyz, use" or "to do xyz, use abc"
 512     /// * may contain a name of a function, variable, or type, but not whole expressions
 513     ///
 514     /// See `CodeSuggestion` for more information.
 515     pub fn span_suggestion(
 516         &mut self,
 517         sp: Span,
 518         msg: &str,
 519         suggestion: String,
 520         applicability: Applicability,
 521     ) -> &mut Self {
 522         self.span_suggestion_with_style(
 523             sp,
 524             msg,
 525             suggestion,
 526             applicability,
 527             SuggestionStyle::ShowCode,
 528         );
 529         self
 530     }
 531
 532     /// [`Diagnostic::span_suggestion()`] but you can set the [`SuggestionStyle`].
 533     pub fn span_suggestion_with_style(
 534         &mut self,
 535         sp: Span,
 536         msg: &str,
 537         suggestion: String,
 538         applicability: Applicability,
 539         style: SuggestionStyle,
 540     ) -> &mut Self {
 541         self.push_suggestion(CodeSuggestion {
 542             substitutions: vec![Substitution {
 543                 parts: vec![SubstitutionPart { snippet: suggestion, span: sp }],
 544             }],
 545             msg: msg.to_owned(),
 546             style,
 547             applicability,
 548             tool_metadata: Default::default(),
 549         });
 550         self
 551     }
 552
 553     /// Always show the suggested change.
 554     pub fn span_suggestion_verbose(
 555         &mut self,
 556         sp: Span,
 557         msg: &str,
 558         suggestion: String,
 559         applicability: Applicability,
 560     ) -> &mut Self {
 561         self.span_suggestion_with_style(
 562             sp,
 563             msg,
 564             suggestion,
 565             applicability,
 566             SuggestionStyle::ShowAlways,
 567         );
 568         self
 569     }
 570
 571     /// Prints out a message with multiple suggested edits of the code.
 572     /// See also [`Diagnostic::span_suggestion()`].
 573     pub fn span_suggestions(
 574         &mut self,
 575         sp: Span,
 576         msg: &str,
 577         suggestions: impl Iterator<Item = String>,
 578         applicability: Applicability,
 579     ) -> &mut Self {
 580         let mut suggestions: Vec<_> = suggestions.collect();
 581         suggestions.sort();
 582         let substitutions = suggestions
 583             .into_iter()
 584             .map(|snippet| Substitution { parts: vec![SubstitutionPart { snippet, span: sp }] })
 585             .collect();
 586         self.push_suggestion(CodeSuggestion {
 587             substitutions,
 588             msg: msg.to_owned(),
 589             style: SuggestionStyle::ShowCode,
 590             applicability,
 591             tool_metadata: Default::default(),
 592         });
 593         self
 594     }
 595
 596     /// Prints out a message with multiple suggested edits of the code.
 597     /// See also [`Diagnostic::span_suggestion()`].
 598     pub fn multipart_suggestions(
 599         &mut self,
 600         msg: &str,
 601         suggestions: impl Iterator<Item = Vec<(Span, String)>>,
 602         applicability: Applicability,
 603     ) -> &mut Self {
 604         self.push_suggestion(CodeSuggestion {
 605             substitutions: suggestions
 606                 .map(|sugg| Substitution {
 607                     parts: sugg
 608                         .into_iter()
 609                         .map(|(span, snippet)| SubstitutionPart { snippet, span })
 610                         .collect(),
 611                 })
 612                 .collect(),
 613             msg: msg.to_owned(),
 614             style: SuggestionStyle::ShowCode,
 615             applicability,
 616             tool_metadata: Default::default(),
 617         });
 618         self
 619     }
 620     /// Prints out a message with a suggested edit of the code. If the suggestion is presented
 621     /// inline, it will only show the message and not the suggestion.
 622     ///
 623     /// See `CodeSuggestion` for more information.
 624     pub fn span_suggestion_short(
 625         &mut self,
 626         sp: Span,
 627         msg: &str,
 628         suggestion: String,
 629         applicability: Applicability,
 630     ) -> &mut Self {
 631         self.span_suggestion_with_style(
 632             sp,
 633             msg,
 634             suggestion,
 635             applicability,
 636             SuggestionStyle::HideCodeInline,
 637         );
 638         self
 639     }
 640
 641     /// Prints out a message for a suggestion without showing the suggested code.
 642     ///
 643     /// This is intended to be used for suggestions that are obvious in what the changes need to
 644     /// be from the message, showing the span label inline would be visually unpleasant
 645     /// (marginally overlapping spans or multiline spans) and showing the snippet window wouldn't
 646     /// improve understandability.
 647     pub fn span_suggestion_hidden(
 648         &mut self,
 649         sp: Span,
 650         msg: &str,
 651         suggestion: String,
 652         applicability: Applicability,
 653     ) -> &mut Self {
 654         self.span_suggestion_with_style(
 655             sp,
 656             msg,
 657             suggestion,
 658             applicability,
 659             SuggestionStyle::HideCodeAlways,
 660         );
 661         self
 662     }
 663
 664     /// Adds a suggestion to the JSON output that will not be shown in the CLI.
 665     ///
 666     /// This is intended to be used for suggestions that are *very* obvious in what the changes
 667     /// need to be from the message, but we still want other tools to be able to apply them.
 668     pub fn tool_only_span_suggestion(
 669         &mut self,
 670         sp: Span,
 671         msg: &str,
 672         suggestion: String,
 673         applicability: Applicability,
 674     ) -> &mut Self {
 675         self.span_suggestion_with_style(
 676             sp,
 677             msg,
 678             suggestion,
 679             applicability,
 680             SuggestionStyle::CompletelyHidden,
 681         );
 682         self
 683     }
 684
 685     /// Adds a suggestion intended only for a tool. The intent is that the metadata encodes
 686     /// the suggestion in a tool-specific way, as it may not even directly involve Rust code.
 687     pub fn tool_only_suggestion_with_metadata(
 688         &mut self,
 689         msg: &str,
 690         applicability: Applicability,
 691         tool_metadata: Json,
 692     ) {
 693         self.push_suggestion(CodeSuggestion {
 694             substitutions: vec![],
 695             msg: msg.to_owned(),
 696             style: SuggestionStyle::CompletelyHidden,
 697             applicability,
 698             tool_metadata: ToolMetadata::new(tool_metadata),
 699         })
 700     }
 701
 702     pub fn set_span<S: Into<MultiSpan>>(&mut self, sp: S) -> &mut Self {
 703         self.span = sp.into();
 704         if let Some(span) = self.span.primary_span() {
 705             self.sort_span = span;
 706         }
 707         self
 708     }
 709
 710     pub fn set_is_lint(&mut self) -> &mut Self {
 711         self.is_lint = true;
 712         self
 713     }
 714
 715     pub fn code(&mut self, s: DiagnosticId) -> &mut Self {
 716         self.code = Some(s);
 717         self
 718     }
 719
 720     pub fn clear_code(&mut self) -> &mut Self {
 721         self.code = None;
 722         self
 723     }
 724
 725     pub fn get_code(&self) -> Option<DiagnosticId> {
 726         self.code.clone()
 727     }
 728
 729     pub fn set_primary_message<M: Into<String>>(&mut self, msg: M) -> &mut Self {
 730         self.message[0] = (msg.into(), Style::NoStyle);
 731         self
 732     }
 733
 734     pub fn message(&self) -> String {
 735         self.message.iter().map(|i| i.0.as_str()).collect::<String>()
 736     }
 737
 738     pub fn styled_message(&self) -> &Vec<(String, Style)> {
 739         &self.message
 740     }
 741
 742     /// Convenience function for internal use, clients should use one of the
 743     /// public methods above.
 744     ///
 745     /// Used by `proc_macro_server` for implementing `server::Diagnostic`.
 746     pub fn sub(
 747         &mut self,
 748         level: Level,
 749         message: &str,
 750         span: MultiSpan,
 751         render_span: Option<MultiSpan>,
 752     ) {
 753         let sub = SubDiagnostic {
 754             level,
 755             message: vec![(message.to_owned(), Style::NoStyle)],
 756             span,
 757             render_span,
 758         };
 759         self.children.push(sub);
 760     }
 761
 762     /// Convenience function for internal use, clients should use one of the
 763     /// public methods above.
 764     fn sub_with_highlights(
 765         &mut self,
 766         level: Level,
 767         message: Vec<(String, Style)>,
 768         span: MultiSpan,
 769         render_span: Option<MultiSpan>,
 770     ) {
 771         let sub = SubDiagnostic { level, message, span, render_span };
 772         self.children.push(sub);
 773     }
 774
 775     /// Fields used for Hash, and PartialEq trait
 776     fn keys(
 777         &self,
 778     ) -> (
 779         &Level,
 780         &Vec<(String, Style)>,
 781         &Option<DiagnosticId>,
 782         &MultiSpan,
 783         &Result<Vec<CodeSuggestion>, SuggestionsDisabled>,
 784         Option<&Vec<SubDiagnostic>>,
 785     ) {
 786         (
 787             &self.level,
 788             &self.message,
 789             &self.code,
 790             &self.span,
 791             &self.suggestions,
 792             (if self.is_lint { None } else { Some(&self.children) }),
 793         )
 794     }
 795 }
 796
 797 impl Hash for Diagnostic {
 798     fn hash<H>(&self, state: &mut H)
 799     where
 800         H: Hasher,
 801     {
 802         self.keys().hash(state);
 803     }
 804 }
 805
 806 impl PartialEq for Diagnostic {
 807     fn eq(&self, other: &Self) -> bool {
 808         self.keys() == other.keys()
 809     }
 810 }
 811
 812 impl SubDiagnostic {
 813     pub fn message(&self) -> String {
 814         self.message.iter().map(|i| i.0.as_str()).collect::<String>()
 815     }
 816
 817     pub fn styled_message(&self) -> &Vec<(String, Style)> {
 818         &self.message
 819     }
 820 }