Make JsonEmitter more like HumanEmitter.

Use `derive(Setters)` to derive setters, and then change
`JsonEmitter::new` to only have the arguments that are always used.

Author: nnethercote

compiler/rustc_errors/src/emitter.rs

@@ -21,12 +21,11 @@ use crate::{
     FluentBundle, LazyFallbackBundle, Level, MultiSpan, Subdiag, SubstitutionHighlight,
     SuggestionStyle, TerminalUrl,
 };
-use rustc_lint_defs::pluralize;
-
 use derive_setters::Setters;
 use rustc_data_structures::fx::{FxHashMap, FxIndexMap, FxIndexSet};
 use rustc_data_structures::sync::{DynSend, IntoDynSyncSend, Lrc};
 use rustc_error_messages::{FluentArgs, SpanLabel};
+use rustc_lint_defs::pluralize;
 use rustc_span::hygiene::{ExpnKind, MacroKind};
 use std::borrow::Cow;
 use std::cmp::{max, min, Reverse};

compiler/rustc_errors/src/json.rs

@@ -9,9 +9,6 @@
 
 // FIXME: spec the JSON output properly.
 
-use rustc_span::source_map::SourceMap;
-use termcolor::{ColorSpec, WriteColor};
-
 use crate::emitter::{
     should_show_source_code, ColorConfig, Destination, Emitter, HumanEmitter,
     HumanReadableErrorType,
@@ -22,32 +19,39 @@ use crate::{
     diagnostic::IsLint, CodeSuggestion, FluentBundle, LazyFallbackBundle, MultiSpan, SpanLabel,
     Subdiag, TerminalUrl,
 };
-use rustc_lint_defs::Applicability;
-
+use derive_setters::Setters;
 use rustc_data_structures::sync::{IntoDynSyncSend, Lrc};
 use rustc_error_messages::FluentArgs;
+use rustc_lint_defs::Applicability;
 use rustc_span::hygiene::ExpnData;
+use rustc_span::source_map::SourceMap;
 use rustc_span::Span;
+use serde::Serialize;
 use std::error::Report;
 use std::io::{self, Write};
 use std::path::Path;
 use std::sync::{Arc, Mutex};
 use std::vec;
-
-use serde::Serialize;
+use termcolor::{ColorSpec, WriteColor};
 
 #[cfg(test)]
 mod tests;
 
+#[derive(Setters)]
 pub struct JsonEmitter {
+    #[setters(skip)]
     dst: IntoDynSyncSend<Box<dyn Write + Send>>,
     registry: Option<Registry>,
+    #[setters(skip)]
     sm: Lrc<SourceMap>,
     fluent_bundle: Option<Lrc<FluentBundle>>,
+    #[setters(skip)]
     fallback_bundle: LazyFallbackBundle,
+    #[setters(skip)]
     pretty: bool,
     ui_testing: bool,
     ignored_directories_in_source_blocks: Vec<String>,
+    #[setters(skip)]
     json_rendered: HumanReadableErrorType,
     diagnostic_width: Option<usize>,
     macro_backtrace: bool,
@@ -58,42 +62,28 @@ pub struct JsonEmitter {
 impl JsonEmitter {
     pub fn new(
         dst: Box<dyn Write + Send>,
-        registry: Option<Registry>,
-        source_map: Lrc<SourceMap>,
-        fluent_bundle: Option<Lrc<FluentBundle>>,
+        sm: Lrc<SourceMap>,
         fallback_bundle: LazyFallbackBundle,
         pretty: bool,
         json_rendered: HumanReadableErrorType,
-        diagnostic_width: Option<usize>,
-        macro_backtrace: bool,
-        track_diagnostics: bool,
-        terminal_url: TerminalUrl,
     ) -> JsonEmitter {
         JsonEmitter {
             dst: IntoDynSyncSend(dst),
-            registry,
-            sm: source_map,
-            fluent_bundle,
+            registry: None,
+            sm,
+            fluent_bundle: None,
             fallback_bundle,
             pretty,
             ui_testing: false,
             ignored_directories_in_source_blocks: Vec::new(),
             json_rendered,
-            diagnostic_width,
-            macro_backtrace,
-            track_diagnostics,
-            terminal_url,
+            diagnostic_width: None,
+            macro_backtrace: false,
+            track_diagnostics: false,
+            terminal_url: TerminalUrl::No,
         }
     }
 
-    pub fn ui_testing(self, ui_testing: bool) -> Self {
-        Self { ui_testing, ..self }
-    }
-
-    pub fn ignored_directories_in_source_blocks(self, value: Vec<String>) -> Self {
-        Self { ignored_directories_in_source_blocks: value, ..self }
-    }
-
     fn emit(&mut self, val: EmitTyped<'_>) -> io::Result<()> {
         if self.pretty {
             serde_json::to_writer_pretty(&mut *self.dst, &val)?

compiler/rustc_errors/src/json/tests.rs

@@ -48,16 +48,10 @@ fn test_positions(code: &str, span: (u32, u32), expected_output: SpanTestData) {
         let output = Arc::new(Mutex::new(Vec::new()));
         let je = JsonEmitter::new(
             Box::new(Shared { data: output.clone() }),
-            None,
             sm,
-            None,
             fallback_bundle,
-            true,
+            true, // pretty
             HumanReadableErrorType::Short(ColorConfig::Never),
-            None,
-            false,
-            false,
-            TerminalUrl::No,
         );
 
         let span = Span::with_root_ctxt(BytePos(span.0), BytePos(span.1));

compiler/rustc_session/src/session.rs

@@ -1001,21 +1001,21 @@ fn default_emitter(
         config::ErrorOutputType::Json { pretty, json_rendered } => Box::new(
             JsonEmitter::new(
                 Box::new(io::BufWriter::new(io::stderr())),
-                Some(registry),
                 source_map,
-                bundle,
                 fallback_bundle,
                 pretty,
                 json_rendered,
-                sopts.diagnostic_width,
-                macro_backtrace,
-                track_diagnostics,
-                terminal_url,
             )
+            .registry(Some(registry))
+            .fluent_bundle(bundle)
             .ui_testing(sopts.unstable_opts.ui_testing)
             .ignored_directories_in_source_blocks(
                 sopts.unstable_opts.ignore_directory_in_diagnostics_source_blocks.clone(),
-            ),
+            )
+            .diagnostic_width(sopts.diagnostic_width)
+            .macro_backtrace(macro_backtrace)
+            .track_diagnostics(track_diagnostics)
+            .terminal_url(terminal_url),
         ),
     }
 }
@@ -1482,16 +1482,10 @@ fn mk_emitter(output: ErrorOutputType) -> Box<DynEmitter> {
         }
         config::ErrorOutputType::Json { pretty, json_rendered } => Box::new(JsonEmitter::new(
             Box::new(io::BufWriter::new(io::stderr())),
-            None,
             Lrc::new(SourceMap::new(FilePathMapping::empty())),
-            None,
             fallback_bundle,
             pretty,
             json_rendered,
-            None,
-            false,
-            false,
-            TerminalUrl::No,
         )),
     };
     emitter

src/librustdoc/core.rs

@@ -158,18 +158,15 @@ pub(crate) fn new_dcx(
             Box::new(
                 JsonEmitter::new(
                     Box::new(io::BufWriter::new(io::stderr())),
-                    None,
                     source_map,
-                    None,
                     fallback_bundle,
                     pretty,
                     json_rendered,
-                    diagnostic_width,
-                    false,
-                    unstable_opts.track_diagnostics,
-                    TerminalUrl::No,
                 )
-                .ui_testing(unstable_opts.ui_testing),
+                .ui_testing(unstable_opts.ui_testing)
+                .diagnostic_width(diagnostic_width)
+                .track_diagnostics(unstable_opts.track_diagnostics)
+                .terminal_url(TerminalUrl::No),
             )
         }
     };