Rollup merge of rust-lang#142650 - camsteffen:refactor-translator, r=petrochenkov

Refactor Translator

My main motivation was to simplify the usage of `SilentEmitter` for users like rustfmt. A few refactoring opportunities arose along the way.

* Replace `Translate` trait with `Translator` struct
* Replace `Emitter: Translate` with `Emitter::translator`
* Split `SilentEmitter` into `FatalOnlyEmitter` and `SilentEmitter`

Author: tgross35

compiler/rustc_codegen_ssa/src/back/write.rs

@@ -14,10 +14,10 @@ use rustc_data_structures::jobserver::{self, Acquired};
 use rustc_data_structures::memmap::Mmap;
 use rustc_data_structures::profiling::{SelfProfilerRef, VerboseTimingGuard};
 use rustc_errors::emitter::Emitter;
-use rustc_errors::translation::Translate;
+use rustc_errors::translation::Translator;
 use rustc_errors::{
-    Diag, DiagArgMap, DiagCtxt, DiagMessage, ErrCode, FatalError, FluentBundle, Level, MultiSpan,
-    Style, Suggestions,
+    Diag, DiagArgMap, DiagCtxt, DiagMessage, ErrCode, FatalError, Level, MultiSpan, Style,
+    Suggestions,
 };
 use rustc_fs_util::link_or_copy;
 use rustc_hir::def_id::{CrateNum, LOCAL_CRATE};
@@ -1889,16 +1889,6 @@ impl SharedEmitter {
     }
 }
 
-impl Translate for SharedEmitter {
-    fn fluent_bundle(&self) -> Option<&FluentBundle> {
-        None
-    }
-
-    fn fallback_fluent_bundle(&self) -> &FluentBundle {
-        panic!("shared emitter attempted to translate a diagnostic");
-    }
-}
-
 impl Emitter for SharedEmitter {
     fn emit_diagnostic(
         &mut self,
@@ -1932,6 +1922,10 @@ impl Emitter for SharedEmitter {
     fn source_map(&self) -> Option<&SourceMap> {
         None
     }
+
+    fn translator(&self) -> &Translator {
+        panic!("shared emitter attempted to translate a diagnostic");
+    }
 }
 
 impl SharedEmitterMain {

compiler/rustc_driver_impl/src/lib.rs

@@ -38,6 +38,7 @@ use rustc_data_structures::profiling::{
 };
 use rustc_errors::emitter::stderr_destination;
 use rustc_errors::registry::Registry;
+use rustc_errors::translation::Translator;
 use rustc_errors::{ColorConfig, DiagCtxt, ErrCode, FatalError, PResult, markdown};
 use rustc_feature::find_gated_cfg;
 // This avoids a false positive with `-Wunused_crate_dependencies`.
@@ -109,6 +110,10 @@ use crate::session_diagnostics::{
 
 rustc_fluent_macro::fluent_messages! { "../messages.ftl" }
 
+pub fn default_translator() -> Translator {
+    Translator::with_fallback_bundle(DEFAULT_LOCALE_RESOURCES.to_vec(), false)
+}
+
 pub static DEFAULT_LOCALE_RESOURCES: &[&str] = &[
     // tidy-alphabetical-start
     crate::DEFAULT_LOCALE_RESOURCE,
@@ -1413,11 +1418,10 @@ fn report_ice(
     extra_info: fn(&DiagCtxt),
     using_internal_features: &AtomicBool,
 ) {
-    let fallback_bundle =
-        rustc_errors::fallback_fluent_bundle(crate::DEFAULT_LOCALE_RESOURCES.to_vec(), false);
+    let translator = default_translator();
     let emitter = Box::new(rustc_errors::emitter::HumanEmitter::new(
         stderr_destination(rustc_errors::ColorConfig::Auto),
-        fallback_bundle,
+        translator,
     ));
     let dcx = rustc_errors::DiagCtxt::new(emitter);
     let dcx = dcx.handle();

compiler/rustc_error_messages/src/lib.rs

@@ -18,7 +18,7 @@ pub use fluent_bundle::{self, FluentArgs, FluentError, FluentValue};
 use fluent_syntax::parser::ParserError;
 use icu_provider_adapters::fallback::{LocaleFallbackProvider, LocaleFallbacker};
 use intl_memoizer::concurrent::IntlLangMemoizer;
-use rustc_data_structures::sync::IntoDynSyncSend;
+use rustc_data_structures::sync::{DynSend, IntoDynSyncSend};
 use rustc_macros::{Decodable, Encodable};
 use rustc_span::Span;
 use smallvec::SmallVec;
@@ -204,16 +204,16 @@ fn register_functions(bundle: &mut FluentBundle) {
 
 /// Type alias for the result of `fallback_fluent_bundle` - a reference-counted pointer to a lazily
 /// evaluated fluent bundle.
-pub type LazyFallbackBundle = Arc<LazyLock<FluentBundle, impl FnOnce() -> FluentBundle>>;
+pub type LazyFallbackBundle =
+    Arc<LazyLock<FluentBundle, Box<dyn FnOnce() -> FluentBundle + DynSend>>>;
 
 /// Return the default `FluentBundle` with standard "en-US" diagnostic messages.
 #[instrument(level = "trace", skip(resources))]
-#[define_opaque(LazyFallbackBundle)]
 pub fn fallback_fluent_bundle(
     resources: Vec<&'static str>,
     with_directionality_markers: bool,
 ) -> LazyFallbackBundle {
-    Arc::new(LazyLock::new(move || {
+    Arc::new(LazyLock::new(Box::new(move || {
         let mut fallback_bundle = new_bundle(vec![langid!("en-US")]);
 
         register_functions(&mut fallback_bundle);
@@ -228,7 +228,7 @@ pub fn fallback_fluent_bundle(
         }
 
         fallback_bundle
-    }))
+    })))
 }
 
 /// Identifier for the Fluent message/attribute corresponding to a diagnostic message.

compiler/rustc_errors/src/annotate_snippet_emitter_writer.rs

@@ -15,17 +15,15 @@ use rustc_span::source_map::SourceMap;
 use crate::emitter::FileWithAnnotatedLines;
 use crate::registry::Registry;
 use crate::snippet::Line;
-use crate::translation::{Translate, to_fluent_args};
+use crate::translation::{Translator, to_fluent_args};
 use crate::{
-    CodeSuggestion, DiagInner, DiagMessage, Emitter, ErrCode, FluentBundle, LazyFallbackBundle,
-    Level, MultiSpan, Style, Subdiag,
+    CodeSuggestion, DiagInner, DiagMessage, Emitter, ErrCode, Level, MultiSpan, Style, Subdiag,
 };
 
 /// Generates diagnostics using annotate-snippet
 pub struct AnnotateSnippetEmitter {
     source_map: Option<Arc<SourceMap>>,
-    fluent_bundle: Option<Arc<FluentBundle>>,
-    fallback_bundle: LazyFallbackBundle,
+    translator: Translator,
 
     /// If true, hides the longer explanation text
     short_message: bool,
@@ -35,16 +33,6 @@ pub struct AnnotateSnippetEmitter {
     macro_backtrace: bool,
 }
 
-impl Translate for AnnotateSnippetEmitter {
-    fn fluent_bundle(&self) -> Option<&FluentBundle> {
-        self.fluent_bundle.as_deref()
-    }
-
-    fn fallback_fluent_bundle(&self) -> &FluentBundle {
-        &self.fallback_bundle
-    }
-}
-
 impl Emitter for AnnotateSnippetEmitter {
     /// The entry point for the diagnostics generation
     fn emit_diagnostic(&mut self, mut diag: DiagInner, _registry: &Registry) {
@@ -78,6 +66,10 @@ impl Emitter for AnnotateSnippetEmitter {
     fn should_show_explain(&self) -> bool {
         !self.short_message
     }
+
+    fn translator(&self) -> &Translator {
+        &self.translator
+    }
 }
 
 /// Provides the source string for the given `line` of `file`
@@ -104,19 +96,11 @@ fn annotation_level_for_level(level: Level) -> annotate_snippets::Level {
 impl AnnotateSnippetEmitter {
     pub fn new(
         source_map: Option<Arc<SourceMap>>,
-        fluent_bundle: Option<Arc<FluentBundle>>,
-        fallback_bundle: LazyFallbackBundle,
+        translator: Translator,
         short_message: bool,
         macro_backtrace: bool,
     ) -> Self {
-        Self {
-            source_map,
-            fluent_bundle,
-            fallback_bundle,
-            short_message,
-            ui_testing: false,
-            macro_backtrace,
-        }
+        Self { source_map, translator, short_message, ui_testing: false, macro_backtrace }
     }
 
     /// Allows to modify `Self` to enable or disable the `ui_testing` flag.
@@ -137,7 +121,7 @@ impl AnnotateSnippetEmitter {
         _children: &[Subdiag],
         _suggestions: &[CodeSuggestion],
     ) {
-        let message = self.translate_messages(messages, args);
+        let message = self.translator.translate_messages(messages, args);
         if let Some(source_map) = &self.source_map {
             // Make sure our primary file comes first
             let primary_lo = if let Some(primary_span) = msp.primary_span().as_ref() {

compiler/rustc_errors/src/emitter.rs

@@ -35,10 +35,10 @@ use crate::snippet::{
 };
 use crate::styled_buffer::StyledBuffer;
 use crate::timings::TimingRecord;
-use crate::translation::{Translate, to_fluent_args};
+use crate::translation::{Translator, to_fluent_args};
 use crate::{
-    CodeSuggestion, DiagInner, DiagMessage, ErrCode, FluentBundle, LazyFallbackBundle, Level,
-    MultiSpan, Subdiag, SubstitutionHighlight, SuggestionStyle, TerminalUrl,
+    CodeSuggestion, DiagInner, DiagMessage, ErrCode, Level, MultiSpan, Subdiag,
+    SubstitutionHighlight, SuggestionStyle, TerminalUrl,
 };
 
 /// Default column width, used in tests and when terminal dimensions cannot be determined.
@@ -175,7 +175,7 @@ const ANONYMIZED_LINE_NUM: &str = "LL";
 pub type DynEmitter = dyn Emitter + DynSend;
 
 /// Emitter trait for emitting errors and other structured information.
-pub trait Emitter: Translate {
+pub trait Emitter {
     /// Emit a structured diagnostic.
     fn emit_diagnostic(&mut self, diag: DiagInner, registry: &Registry);
 
@@ -212,6 +212,8 @@ pub trait Emitter: Translate {
 
     fn source_map(&self) -> Option<&SourceMap>;
 
+    fn translator(&self) -> &Translator;
+
     /// Formats the substitutions of the primary_span
     ///
     /// There are a lot of conditions to this method, but in short:
@@ -224,13 +226,17 @@ pub trait Emitter: Translate {
     /// * If the current `DiagInner` has multiple suggestions,
     ///   we leave `primary_span` and the suggestions untouched.
     fn primary_span_formatted(
-        &mut self,
+        &self,
         primary_span: &mut MultiSpan,
         suggestions: &mut Vec<CodeSuggestion>,
         fluent_args: &FluentArgs<'_>,
     ) {
         if let Some((sugg, rest)) = suggestions.split_first() {
-            let msg = self.translate_message(&sugg.msg, fluent_args).map_err(Report::new).unwrap();
+            let msg = self
+                .translator()
+                .translate_message(&sugg.msg, fluent_args)
+                .map_err(Report::new)
+                .unwrap();
             if rest.is_empty()
                // ^ if there is only one suggestion
                // don't display multi-suggestions as labels
@@ -491,16 +497,6 @@ pub trait Emitter: Translate {
     }
 }
 
-impl Translate for HumanEmitter {
-    fn fluent_bundle(&self) -> Option<&FluentBundle> {
-        self.fluent_bundle.as_deref()
-    }
-
-    fn fallback_fluent_bundle(&self) -> &FluentBundle {
-        &self.fallback_bundle
-    }
-}
-
 impl Emitter for HumanEmitter {
     fn source_map(&self) -> Option<&SourceMap> {
         self.sm.as_deref()
@@ -538,39 +534,52 @@ impl Emitter for HumanEmitter {
     fn supports_color(&self) -> bool {
         self.dst.supports_color()
     }
+
+    fn translator(&self) -> &Translator {
+        &self.translator
+    }
 }
 
 /// An emitter that does nothing when emitting a non-fatal diagnostic.
 /// Fatal diagnostics are forwarded to `fatal_emitter` to avoid silent
 /// failures of rustc, as witnessed e.g. in issue #89358.
-pub struct SilentEmitter {
+pub struct FatalOnlyEmitter {
     pub fatal_emitter: Box<dyn Emitter + DynSend>,
     pub fatal_note: Option<String>,
-    pub emit_fatal_diagnostic: bool,
 }
 
-impl Translate for SilentEmitter {
-    fn fluent_bundle(&self) -> Option<&FluentBundle> {
+impl Emitter for FatalOnlyEmitter {
+    fn source_map(&self) -> Option<&SourceMap> {
         None
     }
 
-    fn fallback_fluent_bundle(&self) -> &FluentBundle {
-        self.fatal_emitter.fallback_fluent_bundle()
+    fn emit_diagnostic(&mut self, mut diag: DiagInner, registry: &Registry) {
+        if diag.level == Level::Fatal {
+            if let Some(fatal_note) = &self.fatal_note {
+                diag.sub(Level::Note, fatal_note.clone(), MultiSpan::new());
+            }
+            self.fatal_emitter.emit_diagnostic(diag, registry);
+        }
+    }
+
+    fn translator(&self) -> &Translator {
+        self.fatal_emitter.translator()
     }
 }
 
+pub struct SilentEmitter {
+    pub translator: Translator,
+}
+
 impl Emitter for SilentEmitter {
     fn source_map(&self) -> Option<&SourceMap> {
         None
     }
 
-    fn emit_diagnostic(&mut self, mut diag: DiagInner, registry: &Registry) {
-        if self.emit_fatal_diagnostic && diag.level == Level::Fatal {
-            if let Some(fatal_note) = &self.fatal_note {
-                diag.sub(Level::Note, fatal_note.clone(), MultiSpan::new());
-            }
-            self.fatal_emitter.emit_diagnostic(diag, registry);
-        }
+    fn emit_diagnostic(&mut self, _diag: DiagInner, _registry: &Registry) {}
+
+    fn translator(&self) -> &Translator {
+        &self.translator
     }
 }
 
@@ -615,9 +624,8 @@ pub struct HumanEmitter {
     #[setters(skip)]
     dst: IntoDynSyncSend<Destination>,
     sm: Option<Arc<SourceMap>>,
-    fluent_bundle: Option<Arc<FluentBundle>>,
     #[setters(skip)]
-    fallback_bundle: LazyFallbackBundle,
+    translator: Translator,
     short_message: bool,
     ui_testing: bool,
     ignored_directories_in_source_blocks: Vec<String>,
@@ -637,12 +645,11 @@ pub(crate) struct FileWithAnnotatedLines {
 }
 
 impl HumanEmitter {
-    pub fn new(dst: Destination, fallback_bundle: LazyFallbackBundle) -> HumanEmitter {
+    pub fn new(dst: Destination, translator: Translator) -> HumanEmitter {
         HumanEmitter {
             dst: IntoDynSyncSend(dst),
             sm: None,
-            fluent_bundle: None,
-            fallback_bundle,
+            translator,
             short_message: false,
             ui_testing: false,
             ignored_directories_in_source_blocks: Vec::new(),
@@ -1433,7 +1440,7 @@ impl HumanEmitter {
         //                very *weird* formats
         //                see?
         for (text, style) in msgs.iter() {
-            let text = self.translate_message(text, args).map_err(Report::new).unwrap();
+            let text = self.translator.translate_message(text, args).map_err(Report::new).unwrap();
             let text = &normalize_whitespace(&text);
             let lines = text.split('\n').collect::<Vec<_>>();
             if lines.len() > 1 {
@@ -1528,7 +1535,8 @@ impl HumanEmitter {
             }
             let mut line = 0;
             for (text, style) in msgs.iter() {
-                let text = self.translate_message(text, args).map_err(Report::new).unwrap();
+                let text =
+                    self.translator.translate_message(text, args).map_err(Report::new).unwrap();
                 // Account for newlines to align output to its label.
                 for text in normalize_whitespace(&text).lines() {
                     buffer.append(
@@ -1560,7 +1568,7 @@ impl HumanEmitter {
                     .into_iter()
                     .filter_map(|label| match label.label {
                         Some(msg) if label.is_primary => {
-                            let text = self.translate_message(&msg, args).ok()?;
+                            let text = self.translator.translate_message(&msg, args).ok()?;
                             if !text.trim().is_empty() { Some(text.to_string()) } else { None }
                         }
                         _ => None,
@@ -3104,7 +3112,11 @@ impl FileWithAnnotatedLines {
 
                 let label = label.as_ref().map(|m| {
                     normalize_whitespace(
-                        &emitter.translate_message(m, args).map_err(Report::new).unwrap(),
+                        &emitter
+                            .translator()
+                            .translate_message(m, args)
+                            .map_err(Report::new)
+                            .unwrap(),
                     )
                 });