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`

5 files changed, 15 insertions, 17 deletions

diff --git a/compiler/rustc_pattern_analysis/src/constructor.rs b/compiler/rustc_pattern_analysis/src/constructor.rs
index f3e8e547066..3a2a75a638f 100644
--- a/compiler/rustc_pattern_analysis/src/constructor.rs
+++ b/compiler/rustc_pattern_analysis/src/constructor.rs
@@ -180,16 +180,14 @@ use std::cmp::{self, max, min, Ordering};
 use std::fmt;
 use std::iter::once;
 
-use smallvec::SmallVec;
-
 use rustc_apfloat::ieee::{DoubleS, HalfS, IeeeFloat, QuadS, SingleS};
 use rustc_index::bit_set::{BitSet, GrowableBitSet};
 use rustc_index::IndexVec;
+use smallvec::SmallVec;
 
 use self::Constructor::*;
 use self::MaybeInfiniteInt::*;
 use self::SliceKind::*;
-
 use crate::PatCx;
 
 /// Whether we have seen a constructor in the column or not.
diff --git a/compiler/rustc_pattern_analysis/src/lints.rs b/compiler/rustc_pattern_analysis/src/lints.rs
index 892aacd7ac5..6bcef0ec879 100644
--- a/compiler/rustc_pattern_analysis/src/lints.rs
+++ b/compiler/rustc_pattern_analysis/src/lints.rs
@@ -1,11 +1,12 @@
+use rustc_session::lint::builtin::NON_EXHAUSTIVE_OMITTED_PATTERNS;
+use rustc_span::ErrorGuaranteed;
+use tracing::instrument;
+
 use crate::constructor::Constructor;
 use crate::errors::{NonExhaustiveOmittedPattern, NonExhaustiveOmittedPatternLintOnArm, Uncovered};
 use crate::pat_column::PatternColumn;
 use crate::rustc::{RevealedTy, RustcPatCtxt, WitnessPat};
 use crate::MatchArm;
-use rustc_session::lint::builtin::NON_EXHAUSTIVE_OMITTED_PATTERNS;
-use rustc_span::ErrorGuaranteed;
-use tracing::instrument;
 
 /// Traverse the patterns to collect any variants of a non_exhaustive enum that fail to be mentioned
 /// in a given column.
diff --git a/compiler/rustc_pattern_analysis/src/pat.rs b/compiler/rustc_pattern_analysis/src/pat.rs
index a591c3c554b..d91deab160c 100644
--- a/compiler/rustc_pattern_analysis/src/pat.rs
+++ b/compiler/rustc_pattern_analysis/src/pat.rs
@@ -5,11 +5,10 @@ use std::fmt;
 
 use smallvec::{smallvec, SmallVec};
 
+use self::Constructor::*;
 use crate::constructor::{Constructor, Slice, SliceKind};
 use crate::{PatCx, PrivateUninhabitedField};
 
-use self::Constructor::*;
-
 /// A globally unique id to distinguish patterns.
 #[derive(Copy, Clone, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]
 pub(crate) struct PatId(u32);
diff --git a/compiler/rustc_pattern_analysis/src/rustc.rs b/compiler/rustc_pattern_analysis/src/rustc.rs
index 910dd4c6c1a..4a9a71531cc 100644
--- a/compiler/rustc_pattern_analysis/src/rustc.rs
+++ b/compiler/rustc_pattern_analysis/src/rustc.rs
@@ -17,6 +17,7 @@ use rustc_session::lint;
 use rustc_span::{ErrorGuaranteed, Span, DUMMY_SP};
 use rustc_target::abi::{FieldIdx, Integer, VariantIdx, FIRST_VARIANT};
 
+use crate::constructor::Constructor::*;
 use crate::constructor::{
     IntRange, MaybeInfiniteInt, OpaqueId, RangeEnd, Slice, SliceKind, VariantVisibility,
 };
@@ -25,8 +26,6 @@ use crate::pat_column::PatternColumn;
 use crate::usefulness::{compute_match_usefulness, PlaceValidity};
 use crate::{errors, Captures, PatCx, PrivateUninhabitedField};
 
-use crate::constructor::Constructor::*;
-
 // Re-export rustc-specific versions of all these types.
 pub type Constructor<'p, 'tcx> = crate::constructor::Constructor<RustcPatCtxt<'p, 'tcx>>;
 pub type ConstructorSet<'p, 'tcx> = crate::constructor::ConstructorSet<RustcPatCtxt<'p, 'tcx>>;
diff --git a/compiler/rustc_pattern_analysis/src/usefulness.rs b/compiler/rustc_pattern_analysis/src/usefulness.rs
index 76dc338e71c..9710c9e1303 100644
--- a/compiler/rustc_pattern_analysis/src/usefulness.rs
+++ b/compiler/rustc_pattern_analysis/src/usefulness.rs
@@ -709,18 +709,19 @@
 //! I (Nadrieril) prefer to put new tests in `ui/pattern/usefulness` unless there's a specific
 //! reason not to, for example if they crucially depend on a particular feature like `or_patterns`.
 
-use self::PlaceValidity::*;
-use crate::constructor::{Constructor, ConstructorSet, IntRange};
-use crate::pat::{DeconstructedPat, PatId, PatOrWild, WitnessPat};
-use crate::{Captures, MatchArm, PatCx, PrivateUninhabitedField};
+use std::fmt;
+
+#[cfg(feature = "rustc")]
+use rustc_data_structures::stack::ensure_sufficient_stack;
 use rustc_hash::{FxHashMap, FxHashSet};
 use rustc_index::bit_set::BitSet;
 use smallvec::{smallvec, SmallVec};
-use std::fmt;
 use tracing::{debug, instrument};
 
-#[cfg(feature = "rustc")]
-use rustc_data_structures::stack::ensure_sufficient_stack;
+use self::PlaceValidity::*;
+use crate::constructor::{Constructor, ConstructorSet, IntRange};
+use crate::pat::{DeconstructedPat, PatId, PatOrWild, WitnessPat};
+use crate::{Captures, MatchArm, PatCx, PrivateUninhabitedField};
 #[cfg(not(feature = "rustc"))]
 pub fn ensure_sufficient_stack<R>(f: impl FnOnce() -> R) -> R {
     f()