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 Level;
  13 use RenderSpan;
  14 use RenderSpan::Suggestion;
  15 use std::fmt;
  16 use syntax_pos::{MultiSpan, Span};
  17 use snippet::Style;
  18
  19 #[must_use]
  20 #[derive(Clone, Debug, PartialEq, RustcEncodable, RustcDecodable)]
  21 pub struct Diagnostic {
  22     pub level: Level,
  23     pub message: Vec<(String, Style)>,
  24     pub code: Option<String>,
  25     pub span: MultiSpan,
  26     pub children: Vec<SubDiagnostic>,
  27 }
  28
  29 /// For example a note attached to an error.
  30 #[derive(Clone, Debug, PartialEq, RustcEncodable, RustcDecodable)]
  31 pub struct SubDiagnostic {
  32     pub level: Level,
  33     pub message: Vec<(String, Style)>,
  34     pub span: MultiSpan,
  35     pub render_span: Option<RenderSpan>,
  36 }
  37
  38 impl Diagnostic {
  39     pub fn new(level: Level, message: &str) -> Self {
  40         Diagnostic::new_with_code(level, None, message)
  41     }
  42
  43     pub fn new_with_code(level: Level, code: Option<String>, message: &str) -> Self {
  44         Diagnostic {
  45             level: level,
  46             message: vec![(message.to_owned(), Style::NoStyle)],
  47             code: code,
  48             span: MultiSpan::new(),
  49             children: vec![],
  50         }
  51     }
  52
  53     /// Cancel the diagnostic (a structured diagnostic must either be emitted or
  54     /// cancelled or it will panic when dropped).
  55     /// BEWARE: if this DiagnosticBuilder is an error, then creating it will
  56     /// bump the error count on the Handler and cancelling it won't undo that.
  57     /// If you want to decrement the error count you should use `Handler::cancel`.
  58     pub fn cancel(&mut self) {
  59         self.level = Level::Cancelled;
  60     }
  61
  62     pub fn cancelled(&self) -> bool {
  63         self.level == Level::Cancelled
  64     }
  65
  66     pub fn is_fatal(&self) -> bool {
  67         self.level == Level::Fatal
  68     }
  69
  70     /// Add a span/label to be included in the resulting snippet.
  71     /// This is pushed onto the `MultiSpan` that was created when the
  72     /// diagnostic was first built. If you don't call this function at
  73     /// all, and you just supplied a `Span` to create the diagnostic,
  74     /// then the snippet will just include that `Span`, which is
  75     /// called the primary span.
  76     pub fn span_label(&mut self, span: Span, label: &fmt::Display)
  77                       -> &mut Self {
  78         self.span.push_span_label(span, format!("{}", label));
  79         self
  80     }
  81
  82     pub fn note_expected_found(&mut self,
  83                                label: &fmt::Display,
  84                                expected: &fmt::Display,
  85                                found: &fmt::Display)
  86                                -> &mut Self
  87     {
  88         self.note_expected_found_extra(label, expected, found, &"", &"")
  89     }
  90
  91     pub fn note_expected_found_extra(&mut self,
  92                                      label: &fmt::Display,
  93                                      expected: &fmt::Display,
  94                                      found: &fmt::Display,
  95                                      expected_extra: &fmt::Display,
  96                                      found_extra: &fmt::Display)
  97                                      -> &mut Self
  98     {
  99         // For now, just attach these as notes
 100         self.highlighted_note(vec![
 101             (format!("expected {} `", label), Style::NoStyle),
 102             (format!("{}", expected), Style::Highlight),
 103             (format!("`{}\n", expected_extra), Style::NoStyle),
 104             (format!("   found {} `", label), Style::NoStyle),
 105             (format!("{}", found), Style::Highlight),
 106             (format!("`{}", found_extra), Style::NoStyle),
 107         ]);
 108         self
 109     }
 110
 111     pub fn note(&mut self, msg: &str) -> &mut Self {
 112         self.sub(Level::Note, msg, MultiSpan::new(), None);
 113         self
 114     }
 115
 116     pub fn highlighted_note(&mut self, msg: Vec<(String, Style)>) -> &mut Self {
 117         self.sub_with_highlights(Level::Note, msg, MultiSpan::new(), None);
 118         self
 119     }
 120
 121     pub fn span_note<S: Into<MultiSpan>>(&mut self,
 122                                          sp: S,
 123                                          msg: &str)
 124                                          -> &mut Self {
 125         self.sub(Level::Note, msg, sp.into(), None);
 126         self
 127     }
 128
 129     pub fn warn(&mut self, msg: &str) -> &mut Self {
 130         self.sub(Level::Warning, msg, MultiSpan::new(), None);
 131         self
 132     }
 133
 134     pub fn span_warn<S: Into<MultiSpan>>(&mut self,
 135                                          sp: S,
 136                                          msg: &str)
 137                                          -> &mut Self {
 138         self.sub(Level::Warning, msg, sp.into(), None);
 139         self
 140     }
 141
 142     pub fn help(&mut self , msg: &str) -> &mut Self {
 143         self.sub(Level::Help, msg, MultiSpan::new(), None);
 144         self
 145     }
 146
 147     pub fn span_help<S: Into<MultiSpan>>(&mut self,
 148                                          sp: S,
 149                                          msg: &str)
 150                                          -> &mut Self {
 151         self.sub(Level::Help, msg, sp.into(), None);
 152         self
 153     }
 154
 155     /// Prints out a message with a suggested edit of the code.
 156     ///
 157     /// See `diagnostic::RenderSpan::Suggestion` for more information.
 158     pub fn span_suggestion<S: Into<MultiSpan>>(&mut self,
 159                                                sp: S,
 160                                                msg: &str,
 161                                                suggestion: String)
 162                                                -> &mut Self {
 163         self.sub(Level::Help,
 164                  msg,
 165                  MultiSpan::new(),
 166                  Some(Suggestion(CodeSuggestion {
 167                      msp: sp.into(),
 168                      substitutes: vec![suggestion],
 169                  })));
 170         self
 171     }
 172
 173     pub fn set_span<S: Into<MultiSpan>>(&mut self, sp: S) -> &mut Self {
 174         self.span = sp.into();
 175         self
 176     }
 177
 178     pub fn code(&mut self, s: String) -> &mut Self {
 179         self.code = Some(s);
 180         self
 181     }
 182
 183     pub fn message(&self) -> String {
 184         self.message.iter().map(|i| i.0.to_owned()).collect::<String>()
 185     }
 186
 187     pub fn styled_message(&self) -> &Vec<(String, Style)> {
 188         &self.message
 189     }
 190
 191     pub fn level(&self) -> Level {
 192         self.level
 193     }
 194
 195     /// Used by a lint. Copies over all details *but* the "main
 196     /// message".
 197     pub fn copy_details_not_message(&mut self, from: &Diagnostic) {
 198         self.span = from.span.clone();
 199         self.code = from.code.clone();
 200         self.children.extend(from.children.iter().cloned())
 201     }
 202
 203     /// Convenience function for internal use, clients should use one of the
 204     /// public methods above.
 205     fn sub(&mut self,
 206            level: Level,
 207            message: &str,
 208            span: MultiSpan,
 209            render_span: Option<RenderSpan>) {
 210         let sub = SubDiagnostic {
 211             level: level,
 212             message: vec![(message.to_owned(), Style::NoStyle)],
 213             span: span,
 214             render_span: render_span,
 215         };
 216         self.children.push(sub);
 217     }
 218
 219     /// Convenience function for internal use, clients should use one of the
 220     /// public methods above.
 221     fn sub_with_highlights(&mut self,
 222                            level: Level,
 223                            message: Vec<(String, Style)>,
 224                            span: MultiSpan,
 225                            render_span: Option<RenderSpan>) {
 226         let sub = SubDiagnostic {
 227             level: level,
 228             message: message,
 229             span: span,
 230             render_span: render_span,
 231         };
 232         self.children.push(sub);
 233     }
 234 }
 235
 236 impl SubDiagnostic {
 237     pub fn message(&self) -> String {
 238         self.message.iter().map(|i| i.0.to_owned()).collect::<String>()
 239     }
 240
 241     pub fn styled_message(&self) -> &Vec<(String, Style)> {
 242         &self.message
 243     }
 244 }