Auto merge of #125443 - nnethercote:rustfmt-use-decls, r=lcnr,cuviper,GuillaumeGomez

rustfmt `use` declarations

This PR implements https://github.com/rust-lang/compiler-team/issues/750, which changes how `use` declarations are formatted by adding these options to `rustfmt.toml`:
```
group_imports = "StdExternalCrate"
imports_granularity = "Module"
```

r? `@ghost`

10 files changed, 71 insertions, 81 deletions

diff --git a/compiler/rustc_codegen_ssa/src/back/archive.rs b/compiler/rustc_codegen_ssa/src/back/archive.rs
index eade00d75fd..fd39ef2649b 100644
--- a/compiler/rustc_codegen_ssa/src/back/archive.rs
+++ b/compiler/rustc_codegen_ssa/src/back/archive.rs
@@ -1,22 +1,20 @@
-use rustc_data_structures::fx::FxIndexSet;
-use rustc_data_structures::memmap::Mmap;
-use rustc_session::cstore::DllImport;
-use rustc_session::Session;
-use rustc_span::symbol::Symbol;
-
-use super::metadata::search_for_section;
+use std::error::Error;
+use std::fs::{self, File};
+use std::io::{self, Write};
+use std::path::{Path, PathBuf};
 
 use ar_archive_writer::{write_archive_to_stream, ArchiveKind, NewArchiveMember};
 pub use ar_archive_writer::{ObjectReader, DEFAULT_OBJECT_READER};
 use object::read::archive::ArchiveFile;
 use object::read::macho::FatArch;
+use rustc_data_structures::fx::FxIndexSet;
+use rustc_data_structures::memmap::Mmap;
+use rustc_session::cstore::DllImport;
+use rustc_session::Session;
+use rustc_span::symbol::Symbol;
 use tempfile::Builder as TempFileBuilder;
 
-use std::error::Error;
-use std::fs::{self, File};
-use std::io::{self, Write};
-use std::path::{Path, PathBuf};
-
+use super::metadata::search_for_section;
 // Re-exporting for rustc_codegen_llvm::back::archive
 pub use crate::errors::{ArchiveBuildFailure, ExtractBundledLibsError, UnknownArchiveKind};
 
diff --git a/compiler/rustc_codegen_ssa/src/back/command.rs b/compiler/rustc_codegen_ssa/src/back/command.rs
index 3a89be89951..95c4af2e59e 100644
--- a/compiler/rustc_codegen_ssa/src/back/command.rs
+++ b/compiler/rustc_codegen_ssa/src/back/command.rs
@@ -2,10 +2,8 @@
 //! read the arguments that are built up.
 
 use std::ffi::{OsStr, OsString};
-use std::fmt;
-use std::io;
-use std::mem;
 use std::process::{self, Output};
+use std::{fmt, io, mem};
 
 use rustc_target::spec::LldFlavor;
 
diff --git a/compiler/rustc_codegen_ssa/src/back/link.rs b/compiler/rustc_codegen_ssa/src/back/link.rs
index f7460a64d0a..55662bfc2cf 100644
--- a/compiler/rustc_codegen_ssa/src/back/link.rs
+++ b/compiler/rustc_codegen_ssa/src/back/link.rs
@@ -1,3 +1,15 @@
+use std::collections::BTreeSet;
+use std::ffi::OsString;
+use std::fs::{read, File, OpenOptions};
+use std::io::{BufWriter, Write};
+use std::ops::Deref;
+use std::path::{Path, PathBuf};
+use std::process::{ExitStatus, Output, Stdio};
+use std::{env, fmt, fs, io, mem, str};
+
+use cc::windows_registry;
+use itertools::Itertools;
+use regex::Regex;
 use rustc_arena::TypedArena;
 use rustc_ast::CRATE_NODE_ID;
 use rustc_data_structures::fx::{FxIndexMap, FxIndexSet};
@@ -12,9 +24,10 @@ use rustc_middle::bug;
 use rustc_middle::middle::debugger_visualizer::DebuggerVisualizerFile;
 use rustc_middle::middle::dependency_format::Linkage;
 use rustc_middle::middle::exported_symbols::SymbolExportKind;
-use rustc_session::config::LinkerFeaturesCli;
-use rustc_session::config::{self, CFGuard, CrateType, DebugInfo, OutFileName, Strip};
-use rustc_session::config::{OutputFilenames, OutputType, PrintKind, SplitDwarfKind};
+use rustc_session::config::{
+    self, CFGuard, CrateType, DebugInfo, LinkerFeaturesCli, OutFileName, OutputFilenames,
+    OutputType, PrintKind, SplitDwarfKind, Strip,
+};
 use rustc_session::cstore::DllImport;
 use rustc_session::output::{check_file_is_writeable, invalid_output_for_target, out_filename};
 use rustc_session::search_paths::PathKind;
@@ -24,11 +37,13 @@ use rustc_session::utils::NativeLibKind;
 use rustc_session::{filesearch, Session};
 use rustc_span::symbol::Symbol;
 use rustc_target::spec::crt_objects::CrtObjects;
-use rustc_target::spec::LinkSelfContainedDefault;
-use rustc_target::spec::LinkerFlavorCli;
-use rustc_target::spec::{Cc, LinkOutputKind, LinkerFlavor, Lld, PanicStrategy};
-use rustc_target::spec::{LinkSelfContainedComponents, LinkerFeatures};
-use rustc_target::spec::{RelocModel, RelroLevel, SanitizerSet, SplitDebuginfo};
+use rustc_target::spec::{
+    Cc, LinkOutputKind, LinkSelfContainedComponents, LinkSelfContainedDefault, LinkerFeatures,
+    LinkerFlavor, LinkerFlavorCli, Lld, PanicStrategy, RelocModel, RelroLevel, SanitizerSet,
+    SplitDebuginfo,
+};
+use tempfile::Builder as TempFileBuilder;
+use tracing::{debug, info, warn};
 
 use super::archive::{ArchiveBuilder, ArchiveBuilderBuilder};
 use super::command::Command;
@@ -39,21 +54,6 @@ use crate::{
     errors, looks_like_rust_object_file, CodegenResults, CompiledModule, CrateInfo, NativeLib,
 };
 
-use cc::windows_registry;
-use regex::Regex;
-use tempfile::Builder as TempFileBuilder;
-
-use itertools::Itertools;
-use std::collections::BTreeSet;
-use std::ffi::OsString;
-use std::fs::{read, File, OpenOptions};
-use std::io::{BufWriter, Write};
-use std::ops::Deref;
-use std::path::{Path, PathBuf};
-use std::process::{ExitStatus, Output, Stdio};
-use std::{env, fmt, fs, io, mem, str};
-use tracing::{debug, info, warn};
-
 pub fn ensure_removed(dcx: DiagCtxtHandle<'_>, path: &Path) {
     if let Err(e) = fs::remove_file(path) {
         if e.kind() != io::ErrorKind::NotFound {
diff --git a/compiler/rustc_codegen_ssa/src/back/linker.rs b/compiler/rustc_codegen_ssa/src/back/linker.rs
index dd134ebbe6b..febeb7093a3 100644
--- a/compiler/rustc_codegen_ssa/src/back/linker.rs
+++ b/compiler/rustc_codegen_ssa/src/back/linker.rs
@@ -1,8 +1,3 @@
-use super::command::Command;
-use super::symbol_export;
-use crate::errors;
-use rustc_span::symbol::sym;
-
 use std::ffi::{OsStr, OsString};
 use std::fs::{self, File};
 use std::io::prelude::*;
@@ -10,6 +5,7 @@ use std::io::{self, BufWriter};
 use std::path::{Path, PathBuf};
 use std::{env, iter, mem, str};
 
+use cc::windows_registry;
 use rustc_hir::def_id::{CrateNum, LOCAL_CRATE};
 use rustc_metadata::find_native_static_library;
 use rustc_middle::bug;
@@ -19,11 +15,14 @@ use rustc_middle::middle::exported_symbols::{ExportedSymbol, SymbolExportInfo, S
 use rustc_middle::ty::TyCtxt;
 use rustc_session::config::{self, CrateType, DebugInfo, LinkerPluginLto, Lto, OptLevel, Strip};
 use rustc_session::Session;
+use rustc_span::symbol::sym;
 use rustc_target::spec::{Cc, LinkOutputKind, LinkerFlavor, Lld};
-
-use cc::windows_registry;
 use tracing::{debug, warn};
 
+use super::command::Command;
+use super::symbol_export;
+use crate::errors;
+
 /// Disables non-English messages from localized linkers.
 /// Such messages may cause issues with text encoding on Windows (#35785)
 /// and prevent inspection of linker output in case of errors, which we occasionally do.
diff --git a/compiler/rustc_codegen_ssa/src/back/lto.rs b/compiler/rustc_codegen_ssa/src/back/lto.rs
index 5291cad148e..8b6f6b5a220 100644
--- a/compiler/rustc_codegen_ssa/src/back/lto.rs
+++ b/compiler/rustc_codegen_ssa/src/back/lto.rs
@@ -1,12 +1,12 @@
-use super::write::CodegenContext;
-use crate::traits::*;
-use crate::ModuleCodegen;
+use std::ffi::CString;
+use std::sync::Arc;
 
 use rustc_data_structures::memmap::Mmap;
 use rustc_errors::FatalError;
 
-use std::ffi::CString;
-use std::sync::Arc;
+use super::write::CodegenContext;
+use crate::traits::*;
+use crate::ModuleCodegen;
 
 pub struct ThinModule<B: WriteBackendMethods> {
     pub shared: Arc<ThinShared<B>>,
diff --git a/compiler/rustc_codegen_ssa/src/back/metadata.rs b/compiler/rustc_codegen_ssa/src/back/metadata.rs
index 31a03a3c94a..19394029c94 100644
--- a/compiler/rustc_codegen_ssa/src/back/metadata.rs
+++ b/compiler/rustc_codegen_ssa/src/back/metadata.rs
@@ -10,7 +10,6 @@ use object::{
     elf, pe, xcoff, Architecture, BinaryFormat, Endianness, FileFlags, Object, ObjectSection,
     ObjectSymbol, SectionFlags, SectionKind, SubArchitecture, SymbolFlags, SymbolKind, SymbolScope,
 };
-
 use rustc_data_structures::memmap::Mmap;
 use rustc_data_structures::owned_slice::{try_slice_owned, OwnedSlice};
 use rustc_metadata::creader::MetadataLoader;
diff --git a/compiler/rustc_codegen_ssa/src/back/rpath.rs b/compiler/rustc_codegen_ssa/src/back/rpath.rs
index 82070d4453b..42f8c3114ff 100644
--- a/compiler/rustc_codegen_ssa/src/back/rpath.rs
+++ b/compiler/rustc_codegen_ssa/src/back/rpath.rs
@@ -1,8 +1,9 @@
+use std::ffi::OsString;
+use std::path::{Path, PathBuf};
+
 use pathdiff::diff_paths;
 use rustc_data_structures::fx::FxHashSet;
 use rustc_fs_util::try_canonicalize;
-use std::ffi::OsString;
-use std::path::{Path, PathBuf};
 use tracing::debug;
 
 pub struct RPathConfig<'a> {
diff --git a/compiler/rustc_codegen_ssa/src/back/rpath/tests.rs b/compiler/rustc_codegen_ssa/src/back/rpath/tests.rs
index c620e92db1f..0de0b8a52b1 100644
--- a/compiler/rustc_codegen_ssa/src/back/rpath/tests.rs
+++ b/compiler/rustc_codegen_ssa/src/back/rpath/tests.rs
@@ -1,8 +1,8 @@
-use super::RPathConfig;
-use super::{get_rpath_relative_to_output, minimize_rpaths, rpaths_to_flags};
 use std::ffi::OsString;
 use std::path::{Path, PathBuf};
 
+use super::{get_rpath_relative_to_output, minimize_rpaths, rpaths_to_flags, RPathConfig};
+
 #[test]
 fn test_rpaths_to_flags() {
     let flags = rpaths_to_flags(vec!["path1".into(), "path2".into()]);
diff --git a/compiler/rustc_codegen_ssa/src/back/symbol_export.rs b/compiler/rustc_codegen_ssa/src/back/symbol_export.rs
index b7ad09b055a..d2f11d48140 100644
--- a/compiler/rustc_codegen_ssa/src/back/symbol_export.rs
+++ b/compiler/rustc_codegen_ssa/src/back/symbol_export.rs
@@ -1,5 +1,3 @@
-use crate::base::allocator_kind_for_codegen;
-
 use std::collections::hash_map::Entry::*;
 
 use rustc_ast::expand::allocator::{ALLOCATOR_METHODS, NO_ALLOC_SHIM_IS_UNSTABLE};
@@ -12,14 +10,14 @@ use rustc_middle::middle::exported_symbols::{
     metadata_symbol_name, ExportedSymbol, SymbolExportInfo, SymbolExportKind, SymbolExportLevel,
 };
 use rustc_middle::query::LocalCrate;
-use rustc_middle::ty::Instance;
-use rustc_middle::ty::{self, SymbolName, TyCtxt};
-use rustc_middle::ty::{GenericArgKind, GenericArgsRef};
+use rustc_middle::ty::{self, GenericArgKind, GenericArgsRef, Instance, SymbolName, TyCtxt};
 use rustc_middle::util::Providers;
 use rustc_session::config::{CrateType, OomStrategy};
 use rustc_target::spec::{SanitizerSet, TlsModel};
 use tracing::debug;
 
+use crate::base::allocator_kind_for_codegen;
+
 pub fn threshold(tcx: TyCtxt<'_>) -> SymbolExportLevel {
     crates_export_threshold(tcx.crate_types())
 }
diff --git a/compiler/rustc_codegen_ssa/src/back/write.rs b/compiler/rustc_codegen_ssa/src/back/write.rs
index 56e94529bc1..bea12747a51 100644
--- a/compiler/rustc_codegen_ssa/src/back/write.rs
+++ b/compiler/rustc_codegen_ssa/src/back/write.rs
@@ -1,12 +1,10 @@
-use super::link::{self, ensure_removed};
-use super::lto::{self, SerializedModule};
-use super::symbol_export::symbol_name_for_instance_in_crate;
+use std::any::Any;
+use std::marker::PhantomData;
+use std::path::{Path, PathBuf};
+use std::sync::mpsc::{channel, Receiver, Sender};
+use std::sync::Arc;
+use std::{fs, io, mem, str, thread};
 
-use crate::errors;
-use crate::traits::*;
-use crate::{
-    CachedModuleCodegen, CodegenResults, CompiledModule, CrateInfo, ModuleCodegen, ModuleKind,
-};
 use jobserver::{Acquired, Client};
 use rustc_ast::attr;
 use rustc_data_structures::fx::{FxHashMap, FxIndexMap};
@@ -30,26 +28,25 @@ use rustc_middle::bug;
 use rustc_middle::dep_graph::{WorkProduct, WorkProductId};
 use rustc_middle::middle::exported_symbols::SymbolExportInfo;
 use rustc_middle::ty::TyCtxt;
-use rustc_session::config::{self, CrateType, Lto, OutFileName, OutputFilenames, OutputType};
-use rustc_session::config::{Passes, SwitchWithOptPath};
+use rustc_session::config::{
+    self, CrateType, Lto, OutFileName, OutputFilenames, OutputType, Passes, SwitchWithOptPath,
+};
 use rustc_session::Session;
 use rustc_span::source_map::SourceMap;
 use rustc_span::symbol::sym;
 use rustc_span::{BytePos, FileName, InnerSpan, Pos, Span};
 use rustc_target::spec::{MergeFunctions, SanitizerSet};
+use tracing::debug;
 
+use super::link::{self, ensure_removed};
+use super::lto::{self, SerializedModule};
+use super::symbol_export::symbol_name_for_instance_in_crate;
 use crate::errors::ErrorCreatingRemarkDir;
-use std::any::Any;
-use std::fs;
-use std::io;
-use std::marker::PhantomData;
-use std::mem;
-use std::path::{Path, PathBuf};
-use std::str;
-use std::sync::mpsc::{channel, Receiver, Sender};
-use std::sync::Arc;
-use std::thread;
-use tracing::debug;
+use crate::traits::*;
+use crate::{
+    errors, CachedModuleCodegen, CodegenResults, CompiledModule, CrateInfo, ModuleCodegen,
+    ModuleKind,
+};
 
 const PRE_LTO_BC_EXT: &str = "pre-lto.bc";