Auto merge of #50204 - Manishearth:approx-enum, r=estebank

Use enum for approximate suggestions

r? @nrc @killercup

7 files changed, 45 insertions, 31 deletions

diff --git a/src/librustc/session/config.rs b/src/librustc/session/config.rs
index ab703d423c6..06922d986b3 100644
--- a/src/librustc/session/config.rs
+++ b/src/librustc/session/config.rs
@@ -1270,7 +1270,7 @@ options! {DebuggingOptions, DebuggingSetter, basic_debugging_options,
     dep_info_omit_d_target: bool = (false, parse_bool, [TRACKED],
         "in dep-info output, omit targets for tracking dependencies of the dep-info files \
          themselves"),
-    approximate_suggestions: bool = (false, parse_bool, [UNTRACKED],
+    suggestion_applicability: bool = (false, parse_bool, [UNTRACKED],
         "include machine-applicability of suggestions in JSON output"),
     unpretty: Option<String> = (None, parse_unpretty, [UNTRACKED],
         "Present the input source, unstable (and less-pretty) variants;
diff --git a/src/librustc/session/mod.rs b/src/librustc/session/mod.rs
index a0f11443425..37a6b2e79f7 100644
--- a/src/librustc/session/mod.rs
+++ b/src/librustc/session/mod.rs
@@ -1002,7 +1002,7 @@ pub fn build_session_with_codemap(
                     Some(registry),
                     codemap.clone(),
                     pretty,
-                    sopts.debugging_opts.approximate_suggestions,
+                    sopts.debugging_opts.suggestion_applicability,
                 ).ui_testing(sopts.debugging_opts.ui_testing),
             ),
             (config::ErrorOutputType::Json(pretty), Some(dst)) => Box::new(
@@ -1011,7 +1011,7 @@ pub fn build_session_with_codemap(
                     Some(registry),
                     codemap.clone(),
                     pretty,
-                    sopts.debugging_opts.approximate_suggestions,
+                    sopts.debugging_opts.suggestion_applicability,
                 ).ui_testing(sopts.debugging_opts.ui_testing),
             ),
             (config::ErrorOutputType::Short(color_config), None) => Box::new(
diff --git a/src/librustc_errors/diagnostic.rs b/src/librustc_errors/diagnostic.rs
index 40e4efb397d..75401f21862 100644
--- a/src/librustc_errors/diagnostic.rs
+++ b/src/librustc_errors/diagnostic.rs
@@ -11,6 +11,7 @@
 use CodeSuggestion;
 use SubstitutionPart;
 use Substitution;
+use Applicability;
 use Level;
 use std::fmt;
 use syntax_pos::{MultiSpan, Span};
@@ -222,7 +223,7 @@ impl Diagnostic {
             }],
             msg: msg.to_owned(),
             show_code_when_inline: false,
-            approximate: false,
+            applicability: Applicability::Unspecified,
         });
         self
     }
@@ -253,7 +254,7 @@ impl Diagnostic {
             }],
             msg: msg.to_owned(),
             show_code_when_inline: true,
-            approximate: false,
+            applicability: Applicability::Unspecified,
         });
         self
     }
@@ -269,15 +270,16 @@ impl Diagnostic {
             }).collect(),
             msg: msg.to_owned(),
             show_code_when_inline: true,
-            approximate: false,
+            applicability: Applicability::Unspecified,
         });
         self
     }
 
     /// This is a suggestion that may contain mistakes or fillers and should
     /// be read and understood by a human.
-    pub fn span_approximate_suggestion(&mut self, sp: Span, msg: &str,
-                                       suggestion: String) -> &mut Self {
+    pub fn span_suggestion_with_applicability(&mut self, sp: Span, msg: &str,
+                                       suggestion: String,
+                                       applicability: Applicability) -> &mut Self {
         self.suggestions.push(CodeSuggestion {
             substitutions: vec![Substitution {
                 parts: vec![SubstitutionPart {
@@ -287,13 +289,14 @@ impl Diagnostic {
             }],
             msg: msg.to_owned(),
             show_code_when_inline: true,
-            approximate: true,
+            applicability,
         });
         self
     }
 
-    pub fn span_approximate_suggestions(&mut self, sp: Span, msg: &str,
-                                        suggestions: Vec<String>) -> &mut Self {
+    pub fn span_suggestions_with_applicability(&mut self, sp: Span, msg: &str,
+                                        suggestions: Vec<String>,
+                                        applicability: Applicability) -> &mut Self {
         self.suggestions.push(CodeSuggestion {
             substitutions: suggestions.into_iter().map(|snippet| Substitution {
                 parts: vec![SubstitutionPart {
@@ -303,7 +306,7 @@ impl Diagnostic {
             }).collect(),
             msg: msg.to_owned(),
             show_code_when_inline: true,
-            approximate: true,
+            applicability,
         });
         self
     }
diff --git a/src/librustc_errors/diagnostic_builder.rs b/src/librustc_errors/diagnostic_builder.rs
index 945ecce7ab3..7e9ca8633a5 100644
--- a/src/librustc_errors/diagnostic_builder.rs
+++ b/src/librustc_errors/diagnostic_builder.rs
@@ -11,6 +11,7 @@
 use Diagnostic;
 use DiagnosticId;
 use DiagnosticStyledString;
+use Applicability;
 
 use Level;
 use Handler;
@@ -187,15 +188,17 @@ impl<'a> DiagnosticBuilder<'a> {
                                      msg: &str,
                                      suggestions: Vec<String>)
                                      -> &mut Self);
-    forward!(pub fn span_approximate_suggestion(&mut self,
+    forward!(pub fn span_suggestion_with_applicability(&mut self,
                                                 sp: Span,
                                                 msg: &str,
-                                                suggestion: String)
+                                                suggestion: String,
+                                                applicability: Applicability)
                                                 -> &mut Self);
-    forward!(pub fn span_approximate_suggestions(&mut self,
+    forward!(pub fn span_suggestions_with_applicability(&mut self,
                                                  sp: Span,
                                                  msg: &str,
-                                                 suggestions: Vec<String>)
+                                                 suggestions: Vec<String>,
+                                                 applicability: Applicability)
                                                  -> &mut Self);
     forward!(pub fn set_span<S: Into<MultiSpan>>(&mut self, sp: S) -> &mut Self);
     forward!(pub fn code(&mut self, s: DiagnosticId) -> &mut Self);
diff --git a/src/librustc_errors/lib.rs b/src/librustc_errors/lib.rs
index ce3efef08cc..c2b442e9497 100644
--- a/src/librustc_errors/lib.rs
+++ b/src/librustc_errors/lib.rs
@@ -56,6 +56,14 @@ mod lock;
 
 use syntax_pos::{BytePos, Loc, FileLinesResult, FileMap, FileName, MultiSpan, Span, NO_EXPANSION};
 
+#[derive(Copy, Clone, Debug, PartialEq, Hash, RustcEncodable, RustcDecodable)]
+pub enum Applicability {
+    MachineApplicable,
+    HasPlaceholders,
+    MaybeIncorrect,
+    Unspecified
+}
+
 #[derive(Clone, Debug, PartialEq, Hash, RustcEncodable, RustcDecodable)]
 pub struct CodeSuggestion {
     /// Each substitute can have multiple variants due to multiple
@@ -87,7 +95,7 @@ pub struct CodeSuggestion {
     /// Sometimes we may show suggestions with placeholders,
     /// which are useful for users but not useful for
     /// tools like rustfix
-    pub approximate: bool,
+    pub applicability: Applicability,
 }
 
 #[derive(Clone, Debug, PartialEq, Hash, RustcEncodable, RustcDecodable)]
diff --git a/src/librustdoc/core.rs b/src/librustdoc/core.rs
index d423203b996..61fb0b40c23 100644
--- a/src/librustdoc/core.rs
+++ b/src/librustdoc/core.rs
@@ -177,7 +177,7 @@ pub fn run_core(search_paths: SearchPaths,
                 None,
                 codemap.clone(),
                 pretty,
-                sessopts.debugging_opts.approximate_suggestions,
+                sessopts.debugging_opts.suggestion_applicability,
             ).ui_testing(sessopts.debugging_opts.ui_testing)
         ),
         ErrorOutputType::Short(color_config) => Box::new(
diff --git a/src/libsyntax/json.rs b/src/libsyntax/json.rs
index b4f34fb12e3..2f15e75093b 100644
--- a/src/libsyntax/json.rs
+++ b/src/libsyntax/json.rs
@@ -23,7 +23,7 @@ use codemap::{CodeMap, FilePathMapping};
 use syntax_pos::{self, MacroBacktrace, Span, SpanLabel, MultiSpan};
 use errors::registry::Registry;
 use errors::{DiagnosticBuilder, SubDiagnostic, CodeSuggestion, CodeMapper};
-use errors::DiagnosticId;
+use errors::{DiagnosticId, Applicability};
 use errors::emitter::{Emitter, EmitterWriter};
 
 use rustc_data_structures::sync::{self, Lrc};
@@ -39,7 +39,7 @@ pub struct JsonEmitter {
     cm: Lrc<CodeMapper + sync::Send + sync::Sync>,
     pretty: bool,
     /// Whether "approximate suggestions" are enabled in the config
-    approximate_suggestions: bool,
+    suggestion_applicability: bool,
     ui_testing: bool,
 }
 
@@ -47,13 +47,13 @@ impl JsonEmitter {
     pub fn stderr(registry: Option<Registry>,
                   code_map: Lrc<CodeMap>,
                   pretty: bool,
-                  approximate_suggestions: bool) -> JsonEmitter {
+                  suggestion_applicability: bool) -> JsonEmitter {
         JsonEmitter {
             dst: Box::new(io::stderr()),
             registry,
             cm: code_map,
             pretty,
-            approximate_suggestions,
+            suggestion_applicability,
             ui_testing: false,
         }
     }
@@ -68,13 +68,13 @@ impl JsonEmitter {
                registry: Option<Registry>,
                code_map: Lrc<CodeMap>,
                pretty: bool,
-               approximate_suggestions: bool) -> JsonEmitter {
+               suggestion_applicability: bool) -> JsonEmitter {
         JsonEmitter {
             dst,
             registry,
             cm: code_map,
             pretty,
-            approximate_suggestions,
+            suggestion_applicability,
             ui_testing: false,
         }
     }
@@ -138,7 +138,7 @@ struct DiagnosticSpan {
     suggested_replacement: Option<String>,
     /// If the suggestion is approximate
     #[rustc_serialize_exclude_null]
-    suggestion_approximate: Option<bool>,
+    suggestion_applicability: Option<Applicability>,
     /// Macro invocations that created the code at this span, if any.
     expansion: Option<Box<DiagnosticSpanMacroExpansion>>,
 }
@@ -239,7 +239,7 @@ impl Diagnostic {
 
 impl DiagnosticSpan {
     fn from_span_label(span: SpanLabel,
-                       suggestion: Option<(&String, bool)>,
+                       suggestion: Option<(&String, Applicability)>,
                        je: &JsonEmitter)
                        -> DiagnosticSpan {
         Self::from_span_etc(span.span,
@@ -252,7 +252,7 @@ impl DiagnosticSpan {
     fn from_span_etc(span: Span,
                      is_primary: bool,
                      label: Option<String>,
-                     suggestion: Option<(&String, bool)>,
+                     suggestion: Option<(&String, Applicability)>,
                      je: &JsonEmitter)
                      -> DiagnosticSpan {
         // obtain the full backtrace from the `macro_backtrace`
@@ -272,7 +272,7 @@ impl DiagnosticSpan {
     fn from_span_full(span: Span,
                       is_primary: bool,
                       label: Option<String>,
-                      suggestion: Option<(&String, bool)>,
+                      suggestion: Option<(&String, Applicability)>,
                       mut backtrace: vec::IntoIter<MacroBacktrace>,
                       je: &JsonEmitter)
                       -> DiagnosticSpan {
@@ -301,7 +301,7 @@ impl DiagnosticSpan {
             })
         });
 
-        let suggestion_approximate = if je.approximate_suggestions {
+        let suggestion_applicability = if je.suggestion_applicability {
              suggestion.map(|x| x.1)
         } else {
             None
@@ -318,7 +318,7 @@ impl DiagnosticSpan {
             is_primary,
             text: DiagnosticSpanLine::from_span(span, je),
             suggested_replacement: suggestion.map(|x| x.0.clone()),
-            suggestion_approximate,
+            suggestion_applicability,
             expansion: backtrace_step,
             label,
         }
@@ -344,7 +344,7 @@ impl DiagnosticSpan {
                               };
                               DiagnosticSpan::from_span_label(span_label,
                                                               Some((&suggestion_inner.snippet,
-                                                                   suggestion.approximate)),
+                                                                   suggestion.applicability)),
                                                               je)
                           })
                       })