Inline and remove JsonEmitter::{basic,stderr}.

They are so similar to `JsonEmitter::new` it's not worth having separate
functions, it makes the code harder to read.

compiler/rustc_errors/src/json.rs

@@ -9,7 +9,7 @@
 
 // FIXME: spec the JSON output properly.
 
-use rustc_span::source_map::{FilePathMapping, SourceMap};
+use rustc_span::source_map::SourceMap;
 use termcolor::{ColorSpec, WriteColor};
 
 use crate::emitter::{
@@ -56,60 +56,6 @@ pub struct JsonEmitter {
 }
 
 impl JsonEmitter {
-    pub fn stderr(
-        registry: Option<Registry>,
-        source_map: Lrc<SourceMap>,
-        fluent_bundle: Option<Lrc<FluentBundle>>,
-        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(Box::new(io::BufWriter::new(io::stderr()))),
-            registry,
-            sm: source_map,
-            fluent_bundle,
-            fallback_bundle,
-            pretty,
-            ui_testing: false,
-            ignored_directories_in_source_blocks: Vec::new(),
-            json_rendered,
-            diagnostic_width,
-            macro_backtrace,
-            track_diagnostics,
-            terminal_url,
-        }
-    }
-
-    pub fn basic(
-        pretty: bool,
-        json_rendered: HumanReadableErrorType,
-        fluent_bundle: Option<Lrc<FluentBundle>>,
-        fallback_bundle: LazyFallbackBundle,
-        diagnostic_width: Option<usize>,
-        macro_backtrace: bool,
-        track_diagnostics: bool,
-        terminal_url: TerminalUrl,
-    ) -> JsonEmitter {
-        let file_path_mapping = FilePathMapping::empty();
-        JsonEmitter::stderr(
-            None,
-            Lrc::new(SourceMap::new(file_path_mapping)),
-            fluent_bundle,
-            fallback_bundle,
-            pretty,
-            json_rendered,
-            diagnostic_width,
-            macro_backtrace,
-            track_diagnostics,
-            terminal_url,
-        )
-    }
-
     pub fn new(
         dst: Box<dyn Write + Send>,
         registry: Option<Registry>,

compiler/rustc_session/src/session.rs

@@ -28,7 +28,7 @@
 use rustc_macros::HashStable_Generic;
 pub use rustc_span::def_id::StableCrateId;
 use rustc_span::edition::Edition;
-use rustc_span::source_map::{FileLoader, RealFileLoader, SourceMap};
+use rustc_span::source_map::{FileLoader, FilePathMapping, RealFileLoader, SourceMap};
 use rustc_span::{SourceFileHashAlgorithm, Span, Symbol};
 use rustc_target::asm::InlineAsmArch;
 use rustc_target::spec::{CodeModel, PanicStrategy, RelocModel, RelroLevel};
@@ -39,6 +39,7 @@
 use std::any::Any;
 use std::env;
 use std::fmt;
+use std::io;
 use std::ops::{Div, Mul};
 use std::path::{Path, PathBuf};
 use std::str::FromStr;
@@ -998,7 +999,8 @@ fn default_emitter(
             }
         }
         config::ErrorOutputType::Json { pretty, json_rendered } => Box::new(
-            JsonEmitter::stderr(
+            JsonEmitter::new(
+                Box::new(io::BufWriter::new(io::stderr())),
                 Some(registry),
                 source_map,
                 bundle,
@@ -1478,11 +1480,14 @@ fn mk_emitter(output: ErrorOutputType) -> Box<DynEmitter> {
                     .short_message(short),
             )
         }
-        config::ErrorOutputType::Json { pretty, json_rendered } => Box::new(JsonEmitter::basic(
-            pretty,
-            json_rendered,
+        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,

src/librustdoc/core.rs

@@ -20,6 +20,7 @@
 use rustc_span::{source_map, Span};
 
 use std::cell::RefCell;
+use std::io;
 use std::mem;
 use std::rc::Rc;
 use std::sync::LazyLock;
@@ -155,7 +156,8 @@ pub(crate) fn new_dcx(
                 Lrc::new(source_map::SourceMap::new(source_map::FilePathMapping::empty()))
             });
             Box::new(
-                JsonEmitter::stderr(
+                JsonEmitter::new(
+                    Box::new(io::BufWriter::new(io::stderr())),
                     None,
                     source_map,
                     None,