src/librustc_errors/diagnostic.rs

   1 // Copyright 2012-2015 The Rust Project Developers. See the COPYRIGHT
   2 // file at the top-level directory of this distribution and at
   3 // http://rust-lang.org/COPYRIGHT.
   4 //
   5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
   6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
   7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
   8 // option. This file may not be copied, modified, or distributed
   9 // except according to those terms.
  10
  11 use CodeSuggestion;
  12 use SubstitutionPart;
  13 use Substitution;
  14 use Applicability;
  15 use Level;
  16 use std::fmt;
  17 use syntax_pos::{MultiSpan, Span};
  18 use snippet::Style;
  19
  20 #[must_use]
  21 #[derive(Clone, Debug, PartialEq, Hash, RustcEncodable, RustcDecodable)]
  22 pub struct Diagnostic {
  23     pub level: Level,
  24     pub message: Vec<(String, Style)>,
  25     pub code: Option<DiagnosticId>,
  26     pub span: MultiSpan,
  27     pub children: Vec<SubDiagnostic>,
  28     pub suggestions: Vec<CodeSuggestion>,
  29 }
  30
  31 #[derive(Clone, Debug, PartialEq, Eq, Hash, RustcEncodable, RustcDecodable)]
  32 pub enum DiagnosticId {
  33     Error(String),
  34     Lint(String),
  35 }
  36
  37 /// For example a note attached to an error.
  38 #[derive(Clone, Debug, PartialEq, Hash, RustcEncodable, RustcDecodable)]
  39 pub struct SubDiagnostic {
  40     pub level: Level,
  41     pub message: Vec<(String, Style)>,
  42     pub span: MultiSpan,
  43     pub render_span: Option<MultiSpan>,
  44 }
  45
  46 #[derive(PartialEq, Eq)]
  47 pub struct DiagnosticStyledString(pub Vec<StringPart>);
  48
  49 impl DiagnosticStyledString {
  50     pub fn new() -> DiagnosticStyledString {
  51         DiagnosticStyledString(vec![])
  52     }
  53     pub fn push_normal<S: Into<String>>(&mut self, t: S) {
  54         self.0.push(StringPart::Normal(t.into()));
  55     }
  56     pub fn push_highlighted<S: Into<String>>(&mut self, t: S) {
  57         self.0.push(StringPart::Highlighted(t.into()));
  58     }
  59     pub fn normal<S: Into<String>>(t: S) -> DiagnosticStyledString {
  60         DiagnosticStyledString(vec![StringPart::Normal(t.into())])
  61     }
  62
  63     pub fn highlighted<S: Into<String>>(t: S) -> DiagnosticStyledString {
  64         DiagnosticStyledString(vec![StringPart::Highlighted(t.into())])
  65     }
  66
  67     pub fn content(&self) -> String {
  68         self.0.iter().map(|x| x.content()).collect::<String>()
  69     }
  70 }
  71
  72 #[derive(PartialEq, Eq)]
  73 pub enum StringPart {
  74     Normal(String),
  75     Highlighted(String),
  76 }
  77
  78 impl StringPart {
  79     pub fn content(&self) -> String {
  80         match self {
  81             &StringPart::Normal(ref s) | & StringPart::Highlighted(ref s) => s.to_owned()
  82         }
  83     }
  84 }
  85
  86 impl Diagnostic {
  87     pub fn new(level: Level, message: &str) -> Self {
  88         Diagnostic::new_with_code(level, None, message)
  89     }
  90
  91     pub fn new_with_code(level: Level, code: Option<DiagnosticId>, message: &str) -> Self {
  92         Diagnostic {
  93             level,
  94             message: vec![(message.to_owned(), Style::NoStyle)],
  95             code,
  96             span: MultiSpan::new(),
  97             children: vec![],
  98             suggestions: vec![],
  99         }
 100     }
 101
 102     pub fn is_error(&self) -> bool {
 103         match self.level {
 104             Level::Bug |
 105             Level::Fatal |
 106             Level::PhaseFatal |
 107             Level::Error |
 108             Level::FailureNote => {
 109                 true
 110             }
 111
 112             Level::Warning |
 113             Level::Note |
 114             Level::Help |
 115             Level::Cancelled => {
 116                 false
 117             }
 118         }
 119     }
 120
 121     /// Cancel the diagnostic (a structured diagnostic must either be emitted or
 122     /// canceled or it will panic when dropped).
 123     pub fn cancel(&mut self) {
 124         self.level = Level::Cancelled;
 125     }
 126
 127     pub fn cancelled(&self) -> bool {
 128         self.level == Level::Cancelled
 129     }
 130
 131     /// Add a span/label to be included in the resulting snippet.
 132     /// This is pushed onto the `MultiSpan` that was created when the
 133     /// diagnostic was first built. If you don't call this function at
 134     /// all, and you just supplied a `Span` to create the diagnostic,
 135     /// then the snippet will just include that `Span`, which is
 136     /// called the primary span.
 137     pub fn span_label<T: Into<String>>(&mut self, span: Span, label: T) -> &mut Self {
 138         self.span.push_span_label(span, label.into());
 139         self
 140     }
 141
 142     pub fn note_expected_found(&mut self,
 143                                label: &dyn fmt::Display,
 144                                expected: DiagnosticStyledString,
 145                                found: DiagnosticStyledString)
 146                                -> &mut Self
 147     {
 148         self.note_expected_found_extra(label, expected, found, &"", &"")
 149     }
 150
 151     pub fn note_expected_found_extra(&mut self,
 152                                      label: &dyn fmt::Display,
 153                                      expected: DiagnosticStyledString,
 154                                      found: DiagnosticStyledString,
 155                                      expected_extra: &dyn fmt::Display,
 156                                      found_extra: &dyn fmt::Display)
 157                                      -> &mut Self
 158     {
 159         let mut msg: Vec<_> = vec![(format!("expected {} `", label), Style::NoStyle)];
 160         msg.extend(expected.0.iter()
 161                    .map(|x| match *x {
 162                        StringPart::Normal(ref s) => (s.to_owned(), Style::NoStyle),
 163                        StringPart::Highlighted(ref s) => (s.to_owned(), Style::Highlight),
 164                    }));
 165         msg.push((format!("`{}\n", expected_extra), Style::NoStyle));
 166         msg.push((format!("   found {} `", label), Style::NoStyle));
 167         msg.extend(found.0.iter()
 168                    .map(|x| match *x {
 169                        StringPart::Normal(ref s) => (s.to_owned(), Style::NoStyle),
 170                        StringPart::Highlighted(ref s) => (s.to_owned(), Style::Highlight),
 171                    }));
 172         msg.push((format!("`{}", found_extra), Style::NoStyle));
 173
 174         // For now, just attach these as notes
 175         self.highlighted_note(msg);
 176         self
 177     }
 178
 179     pub fn note_trait_signature(&mut self, name: String, signature: String) -> &mut Self {
 180         self.highlighted_note(vec![
 181             (format!("`{}` from trait: `", name), Style::NoStyle),
 182             (signature, Style::Highlight),
 183             ("`".to_string(), Style::NoStyle)]);
 184         self
 185     }
 186
 187     pub fn note(&mut self, msg: &str) -> &mut Self {
 188         self.sub(Level::Note, msg, MultiSpan::new(), None);
 189         self
 190     }
 191
 192     pub fn highlighted_note(&mut self, msg: Vec<(String, Style)>) -> &mut Self {
 193         self.sub_with_highlights(Level::Note, msg, MultiSpan::new(), None);
 194         self
 195     }
 196
 197     pub fn span_note<S: Into<MultiSpan>>(&mut self,
 198                                          sp: S,
 199                                          msg: &str)
 200                                          -> &mut Self {
 201         self.sub(Level::Note, msg, sp.into(), None);
 202         self
 203     }
 204
 205     pub fn warn(&mut self, msg: &str) -> &mut Self {
 206         self.sub(Level::Warning, msg, MultiSpan::new(), None);
 207         self
 208     }
 209
 210     pub fn span_warn<S: Into<MultiSpan>>(&mut self,
 211                                          sp: S,
 212                                          msg: &str)
 213                                          -> &mut Self {
 214         self.sub(Level::Warning, msg, sp.into(), None);
 215         self
 216     }
 217
 218     pub fn help(&mut self , msg: &str) -> &mut Self {
 219         self.sub(Level::Help, msg, MultiSpan::new(), None);
 220         self
 221     }
 222
 223     pub fn span_help<S: Into<MultiSpan>>(&mut self,
 224                                          sp: S,
 225                                          msg: &str)
 226                                          -> &mut Self {
 227         self.sub(Level::Help, msg, sp.into(), None);
 228         self
 229     }
 230
 231     /// Prints out a message with a suggested edit of the code. If the suggestion is presented
 232     /// inline it will only show the text message and not the text.
 233     ///
 234     /// See `CodeSuggestion` for more information.
 235     #[deprecated(note = "Use `span_suggestion_short_with_applicability`")]
 236     pub fn span_suggestion_short(&mut self, sp: Span, msg: &str, suggestion: String) -> &mut Self {
 237         self.suggestions.push(CodeSuggestion {
 238             substitutions: vec![Substitution {
 239                 parts: vec![SubstitutionPart {
 240                     snippet: suggestion,
 241                     span: sp,
 242                 }],
 243             }],
 244             msg: msg.to_owned(),
 245             show_code_when_inline: false,
 246             applicability: Applicability::Unspecified,
 247         });
 248         self
 249     }
 250
 251     /// Prints out a message with a suggested edit of the code.
 252     ///
 253     /// In case of short messages and a simple suggestion,
 254     /// rustc displays it as a label like
 255     ///
 256     /// "try adding parentheses: `(tup.0).1`"
 257     ///
 258     /// The message
 259     ///
 260     /// * should not end in any punctuation (a `:` is added automatically)
 261     /// * should not be a question
 262     /// * should not contain any parts like "the following", "as shown"
 263     /// * may look like "to do xyz, use" or "to do xyz, use abc"
 264     /// * may contain a name of a function, variable or type, but not whole expressions
 265     ///
 266     /// See `CodeSuggestion` for more information.
 267     #[deprecated(note = "Use `span_suggestion_with_applicability`")]
 268     pub fn span_suggestion(&mut self, sp: Span, msg: &str, suggestion: String) -> &mut Self {
 269         self.suggestions.push(CodeSuggestion {
 270             substitutions: vec![Substitution {
 271                 parts: vec![SubstitutionPart {
 272                     snippet: suggestion,
 273                     span: sp,
 274                 }],
 275             }],
 276             msg: msg.to_owned(),
 277             show_code_when_inline: true,
 278             applicability: Applicability::Unspecified,
 279         });
 280         self
 281     }
 282
 283     pub fn multipart_suggestion_with_applicability(
 284         &mut self,
 285         msg: &str,
 286         suggestion: Vec<(Span, String)>,
 287         applicability: Applicability,
 288     ) -> &mut Self {
 289         self.suggestions.push(CodeSuggestion {
 290             substitutions: vec![Substitution {
 291                 parts: suggestion
 292                     .into_iter()
 293                     .map(|(span, snippet)| SubstitutionPart { snippet, span })
 294                     .collect(),
 295             }],
 296             msg: msg.to_owned(),
 297             show_code_when_inline: true,
 298             applicability,
 299         });
 300         self
 301     }
 302
 303     #[deprecated(note = "Use `multipart_suggestion_with_applicability`")]
 304     pub fn multipart_suggestion(
 305         &mut self,
 306         msg: &str,
 307         suggestion: Vec<(Span, String)>,
 308     ) -> &mut Self {
 309         self.multipart_suggestion_with_applicability(
 310             msg,
 311             suggestion,
 312             Applicability::Unspecified,
 313         )
 314     }
 315
 316     /// Prints out a message with multiple suggested edits of the code.
 317     #[deprecated(note = "Use `span_suggestions_with_applicability`")]
 318     pub fn span_suggestions(&mut self, sp: Span, msg: &str, suggestions: Vec<String>) -> &mut Self {
 319         self.suggestions.push(CodeSuggestion {
 320             substitutions: suggestions.into_iter().map(|snippet| Substitution {
 321                 parts: vec![SubstitutionPart {
 322                     snippet,
 323                     span: sp,
 324                 }],
 325             }).collect(),
 326             msg: msg.to_owned(),
 327             show_code_when_inline: true,
 328             applicability: Applicability::Unspecified,
 329         });
 330         self
 331     }
 332
 333     /// This is a suggestion that may contain mistakes or fillers and should
 334     /// be read and understood by a human.
 335     pub fn span_suggestion_with_applicability(&mut self, sp: Span, msg: &str,
 336                                        suggestion: String,
 337                                        applicability: Applicability) -> &mut Self {
 338         self.suggestions.push(CodeSuggestion {
 339             substitutions: vec![Substitution {
 340                 parts: vec![SubstitutionPart {
 341                     snippet: suggestion,
 342                     span: sp,
 343                 }],
 344             }],
 345             msg: msg.to_owned(),
 346             show_code_when_inline: true,
 347             applicability,
 348         });
 349         self
 350     }
 351
 352     pub fn span_suggestions_with_applicability(&mut self, sp: Span, msg: &str,
 353                                         suggestions: Vec<String>,
 354                                         applicability: Applicability) -> &mut Self {
 355         self.suggestions.push(CodeSuggestion {
 356             substitutions: suggestions.into_iter().map(|snippet| Substitution {
 357                 parts: vec![SubstitutionPart {
 358                     snippet,
 359                     span: sp,
 360                 }],
 361             }).collect(),
 362             msg: msg.to_owned(),
 363             show_code_when_inline: true,
 364             applicability,
 365         });
 366         self
 367     }
 368
 369     pub fn span_suggestion_short_with_applicability(
 370         &mut self, sp: Span, msg: &str, suggestion: String, applicability: Applicability
 371     ) -> &mut Self {
 372         self.suggestions.push(CodeSuggestion {
 373             substitutions: vec![Substitution {
 374                 parts: vec![SubstitutionPart {
 375                     snippet: suggestion,
 376                     span: sp,
 377                 }],
 378             }],
 379             msg: msg.to_owned(),
 380             show_code_when_inline: false,
 381             applicability: applicability,
 382         });
 383         self
 384     }
 385
 386     pub fn set_span<S: Into<MultiSpan>>(&mut self, sp: S) -> &mut Self {
 387         self.span = sp.into();
 388         self
 389     }
 390
 391     pub fn code(&mut self, s: DiagnosticId) -> &mut Self {
 392         self.code = Some(s);
 393         self
 394     }
 395
 396     pub fn get_code(&self) -> Option<DiagnosticId> {
 397         self.code.clone()
 398     }
 399
 400     pub fn message(&self) -> String {
 401         self.message.iter().map(|i| i.0.to_owned()).collect::<String>()
 402     }
 403
 404     pub fn styled_message(&self) -> &Vec<(String, Style)> {
 405         &self.message
 406     }
 407
 408     /// Used by a lint. Copies over all details *but* the "main
 409     /// message".
 410     pub fn copy_details_not_message(&mut self, from: &Diagnostic) {
 411         self.span = from.span.clone();
 412         self.code = from.code.clone();
 413         self.children.extend(from.children.iter().cloned())
 414     }
 415
 416     /// Convenience function for internal use, clients should use one of the
 417     /// public methods above.
 418     pub fn sub(&mut self,
 419            level: Level,
 420            message: &str,
 421            span: MultiSpan,
 422            render_span: Option<MultiSpan>) {
 423         let sub = SubDiagnostic {
 424             level,
 425             message: vec![(message.to_owned(), Style::NoStyle)],
 426             span,
 427             render_span,
 428         };
 429         self.children.push(sub);
 430     }
 431
 432     /// Convenience function for internal use, clients should use one of the
 433     /// public methods above.
 434     fn sub_with_highlights(&mut self,
 435                            level: Level,
 436                            message: Vec<(String, Style)>,
 437                            span: MultiSpan,
 438                            render_span: Option<MultiSpan>) {
 439         let sub = SubDiagnostic {
 440             level,
 441             message,
 442             span,
 443             render_span,
 444         };
 445         self.children.push(sub);
 446     }
 447 }
 448
 449 impl SubDiagnostic {
 450     pub fn message(&self) -> String {
 451         self.message.iter().map(|i| i.0.to_owned()).collect::<String>()
 452     }
 453
 454     pub fn styled_message(&self) -> &Vec<(String, Style)> {
 455         &self.message
 456     }
 457 }