Rollup merge of #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`

5 files changed, 36 insertions, 71 deletions

diff --git a/src/librustdoc/core.rs b/src/librustdoc/core.rs
index d73600a4636..cf3c4ac97af 100644
--- a/src/librustdoc/core.rs
+++ b/src/librustdoc/core.rs
@@ -149,15 +149,12 @@ pub(crate) fn new_dcx(
     diagnostic_width: Option<usize>,
     unstable_opts: &UnstableOptions,
 ) -> rustc_errors::DiagCtxt {
-    let fallback_bundle = rustc_errors::fallback_fluent_bundle(
-        rustc_driver::DEFAULT_LOCALE_RESOURCES.to_vec(),
-        false,
-    );
+    let translator = rustc_driver::default_translator();
     let emitter: Box<DynEmitter> = match error_format {
         ErrorOutputType::HumanReadable { kind, color_config } => {
             let short = kind.short();
             Box::new(
-                HumanEmitter::new(stderr_destination(color_config), fallback_bundle)
+                HumanEmitter::new(stderr_destination(color_config), translator)
                     .sm(source_map.map(|sm| sm as _))
                     .short_message(short)
                     .diagnostic_width(diagnostic_width)
@@ -178,7 +175,7 @@ pub(crate) fn new_dcx(
                 JsonEmitter::new(
                     Box::new(io::BufWriter::new(io::stderr())),
                     Some(source_map),
-                    fallback_bundle,
+                    translator,
                     pretty,
                     json_rendered,
                     color_config,
diff --git a/src/librustdoc/doctest/make.rs b/src/librustdoc/doctest/make.rs
index 3ff6828e52f..f229f77c978 100644
--- a/src/librustdoc/doctest/make.rs
+++ b/src/librustdoc/doctest/make.rs
@@ -456,16 +456,13 @@ fn parse_source(
     let filename = FileName::anon_source_code(&wrapped_source);
 
     let sm = Arc::new(SourceMap::new(FilePathMapping::empty()));
-    let fallback_bundle = rustc_errors::fallback_fluent_bundle(
-        rustc_driver::DEFAULT_LOCALE_RESOURCES.to_vec(),
-        false,
-    );
+    let translator = rustc_driver::default_translator();
     info.supports_color =
-        HumanEmitter::new(stderr_destination(ColorConfig::Auto), fallback_bundle.clone())
+        HumanEmitter::new(stderr_destination(ColorConfig::Auto), translator.clone())
             .supports_color();
     // Any errors in parsing should also appear when the doctest is compiled for real, so just
     // send all the errors that the parser emits directly into a `Sink` instead of stderr.
-    let emitter = HumanEmitter::new(Box::new(io::sink()), fallback_bundle);
+    let emitter = HumanEmitter::new(Box::new(io::sink()), translator);
 
     // FIXME(misdreavus): pass `-Z treat-err-as-bug` to the doctest parser
     let dcx = DiagCtxt::new(Box::new(emitter)).disable_warnings();
diff --git a/src/librustdoc/passes/lint/check_code_block_syntax.rs b/src/librustdoc/passes/lint/check_code_block_syntax.rs
index 9662dd85d67..91cddbe5a5b 100644
--- a/src/librustdoc/passes/lint/check_code_block_syntax.rs
+++ b/src/librustdoc/passes/lint/check_code_block_syntax.rs
@@ -6,8 +6,8 @@ use std::sync::Arc;
 use rustc_data_structures::sync::Lock;
 use rustc_errors::emitter::Emitter;
 use rustc_errors::registry::Registry;
-use rustc_errors::translation::{Translate, to_fluent_args};
-use rustc_errors::{Applicability, DiagCtxt, DiagInner, LazyFallbackBundle};
+use rustc_errors::translation::{Translator, to_fluent_args};
+use rustc_errors::{Applicability, DiagCtxt, DiagInner};
 use rustc_parse::{source_str_to_stream, unwrap_or_emit_fatal};
 use rustc_resolve::rustdoc::source_span_for_markdown_range;
 use rustc_session::parse::ParseSess;
@@ -36,11 +36,8 @@ fn check_rust_syntax(
     code_block: RustCodeBlock,
 ) {
     let buffer = Arc::new(Lock::new(Buffer::default()));
-    let fallback_bundle = rustc_errors::fallback_fluent_bundle(
-        rustc_driver::DEFAULT_LOCALE_RESOURCES.to_vec(),
-        false,
-    );
-    let emitter = BufferEmitter { buffer: Arc::clone(&buffer), fallback_bundle };
+    let translator = rustc_driver::default_translator();
+    let emitter = BufferEmitter { buffer: Arc::clone(&buffer), translator };
 
     let sm = Arc::new(SourceMap::new(FilePathMapping::empty()));
     let dcx = DiagCtxt::new(Box::new(emitter)).disable_warnings();
@@ -149,17 +146,7 @@ struct Buffer {
 
 struct BufferEmitter {
     buffer: Arc<Lock<Buffer>>,
-    fallback_bundle: LazyFallbackBundle,
-}
-
-impl Translate for BufferEmitter {
-    fn fluent_bundle(&self) -> Option<&rustc_errors::FluentBundle> {
-        None
-    }
-
-    fn fallback_fluent_bundle(&self) -> &rustc_errors::FluentBundle {
-        &self.fallback_bundle
-    }
+    translator: Translator,
 }
 
 impl Emitter for BufferEmitter {
@@ -168,6 +155,7 @@ impl Emitter for BufferEmitter {
 
         let fluent_args = to_fluent_args(diag.args.iter());
         let translated_main_message = self
+            .translator
             .translate_message(&diag.messages[0].0, &fluent_args)
             .unwrap_or_else(|e| panic!("{e}"));
 
@@ -180,4 +168,8 @@ impl Emitter for BufferEmitter {
     fn source_map(&self) -> Option<&SourceMap> {
         None
     }
+
+    fn translator(&self) -> &Translator {
+        &self.translator
+    }
 }
diff --git a/src/tools/clippy/clippy_lints/src/doc/needless_doctest_main.rs b/src/tools/clippy/clippy_lints/src/doc/needless_doctest_main.rs
index ec4538039a9..7ba11c20f45 100644
--- a/src/tools/clippy/clippy_lints/src/doc/needless_doctest_main.rs
+++ b/src/tools/clippy/clippy_lints/src/doc/needless_doctest_main.rs
@@ -42,9 +42,8 @@ pub fn check(
                 let mut test_attr_spans = vec![];
                 let filename = FileName::anon_source_code(&code);
 
-                let fallback_bundle =
-                    rustc_errors::fallback_fluent_bundle(rustc_driver::DEFAULT_LOCALE_RESOURCES.to_vec(), false);
-                let emitter = HumanEmitter::new(Box::new(io::sink()), fallback_bundle);
+                let translator = rustc_driver::default_translator();
+                let emitter = HumanEmitter::new(Box::new(io::sink()), translator);
                 let dcx = DiagCtxt::new(Box::new(emitter)).disable_warnings();
                 #[expect(clippy::arc_with_non_send_sync)] // `Arc` is expected by with_dcx
                 let sm = Arc::new(SourceMap::new(FilePathMapping::empty()));
diff --git a/src/tools/rustfmt/src/parse/session.rs b/src/tools/rustfmt/src/parse/session.rs
index afd847f9515..10e2809e58b 100644
--- a/src/tools/rustfmt/src/parse/session.rs
+++ b/src/tools/rustfmt/src/parse/session.rs
@@ -5,7 +5,7 @@ use std::sync::atomic::{AtomicBool, Ordering};
 use rustc_data_structures::sync::IntoDynSyncSend;
 use rustc_errors::emitter::{DynEmitter, Emitter, HumanEmitter, SilentEmitter, stderr_destination};
 use rustc_errors::registry::Registry;
-use rustc_errors::translation::Translate;
+use rustc_errors::translation::Translator;
 use rustc_errors::{ColorConfig, Diag, DiagCtxt, DiagInner, Level as DiagnosticLevel};
 use rustc_session::parse::ParseSess as RawParseSess;
 use rustc_span::{
@@ -47,16 +47,6 @@ impl SilentOnIgnoredFilesEmitter {
     }
 }
 
-impl Translate for SilentOnIgnoredFilesEmitter {
-    fn fluent_bundle(&self) -> Option<&rustc_errors::FluentBundle> {
-        self.emitter.fluent_bundle()
-    }
-
-    fn fallback_fluent_bundle(&self) -> &rustc_errors::FluentBundle {
-        self.emitter.fallback_fluent_bundle()
-    }
-}
-
 impl Emitter for SilentOnIgnoredFilesEmitter {
     fn source_map(&self) -> Option<&SourceMap> {
         None
@@ -84,6 +74,10 @@ impl Emitter for SilentOnIgnoredFilesEmitter {
         }
         self.handle_non_ignoreable_error(diag, registry);
     }
+
+    fn translator(&self) -> &Translator {
+        self.emitter.translator()
+    }
 }
 
 impl From<Color> for ColorConfig {
@@ -110,23 +104,15 @@ fn default_dcx(
         ColorConfig::Never
     };
 
-    let fallback_bundle = rustc_errors::fallback_fluent_bundle(
-        rustc_driver::DEFAULT_LOCALE_RESOURCES.to_vec(),
-        false,
-    );
-    let emitter = Box::new(
-        HumanEmitter::new(stderr_destination(emit_color), fallback_bundle)
-            .sm(Some(source_map.clone())),
-    );
-
-    let emitter: Box<DynEmitter> = if !show_parse_errors {
-        Box::new(SilentEmitter {
-            fatal_emitter: emitter,
-            fatal_note: None,
-            emit_fatal_diagnostic: false,
-        })
+    let translator = rustc_driver::default_translator();
+
+    let emitter: Box<DynEmitter> = if show_parse_errors {
+        Box::new(
+            HumanEmitter::new(stderr_destination(emit_color), translator)
+                .sm(Some(source_map.clone())),
+        )
     } else {
-        emitter
+        Box::new(SilentEmitter { translator })
     };
     DiagCtxt::new(Box::new(SilentOnIgnoredFilesEmitter {
         has_non_ignorable_parser_errors: false,
@@ -205,7 +191,7 @@ impl ParseSess {
     }
 
     pub(crate) fn set_silent_emitter(&mut self) {
-        self.raw_psess.dcx().make_silent(None, false);
+        self.raw_psess.dcx().make_silent();
     }
 
     pub(crate) fn span_to_filename(&self, span: Span) -> FileName {
@@ -335,16 +321,6 @@ mod tests {
             num_emitted_errors: Arc<AtomicU32>,
         }
 
-        impl Translate for TestEmitter {
-            fn fluent_bundle(&self) -> Option<&rustc_errors::FluentBundle> {
-                None
-            }
-
-            fn fallback_fluent_bundle(&self) -> &rustc_errors::FluentBundle {
-                panic!("test emitter attempted to translate a diagnostic");
-            }
-        }
-
         impl Emitter for TestEmitter {
             fn source_map(&self) -> Option<&SourceMap> {
                 None
@@ -353,6 +329,10 @@ mod tests {
             fn emit_diagnostic(&mut self, _diag: DiagInner, _registry: &Registry) {
                 self.num_emitted_errors.fetch_add(1, Ordering::Release);
             }
+
+            fn translator(&self) -> &Translator {
+                panic!("test emitter attempted to translate a diagnostic");
+            }
         }
 
         fn build_diagnostic(level: DiagnosticLevel, span: Option<MultiSpan>) -> DiagInner {