Rollup merge of rust-lang#126717 - nnethercote:rustfmt-use-pre-cleanups, r=jieyouxu

Clean up some comments near `use` declarations

rust-lang#125443 will reformat all `use` declarations in the repository. There are a few edge cases involving comments on `use` declarations that require care. This PR cleans up some clumsy comment cases, taking us a step closer to rust-lang#125443 being able to merge.

r? `@lqd`

Author: matthiaskrgr

compiler/rustc_builtin_macros/src/test.rs

@@ -1,6 +1,7 @@
+//! The expansion from a test function to the appropriate test struct for libtest
+//! Ideally, this code would be in libtest but for efficiency and error messages it lives here.
+
 use crate::errors;
-/// The expansion from a test function to the appropriate test struct for libtest
-/// Ideally, this code would be in libtest but for efficiency and error messages it lives here.
 use crate::util::{check_builtin_macro_attribute, warn_on_duplicate_attribute};
 use rustc_ast::ptr::P;
 use rustc_ast::{self as ast, attr, GenericParamKind};

compiler/rustc_codegen_gcc/tests/lang_tests_common.rs

@@ -1,4 +1,5 @@
 //! The common code for `tests/lang_tests_*.rs`
+
 use std::{
     env::{self, current_dir},
     path::{Path, PathBuf},

compiler/rustc_codegen_ssa/src/mir/locals.rs

@@ -1,6 +1,7 @@
 //! Locals are in a private module as updating `LocalRef::Operand` has to
 //! be careful wrt to subtyping. To deal with this we only allow updates by using
 //! `FunctionCx::overwrite_local` which handles it automatically.
+
 use crate::mir::{FunctionCx, LocalRef};
 use crate::traits::BuilderMethods;
 use rustc_index::IndexVec;

compiler/rustc_data_structures/src/base_n.rs

@@ -1,5 +1,6 @@
-/// Converts unsigned integers into a string representation with some base.
-/// Bases up to and including 36 can be used for case-insensitive things.
+//! Converts unsigned integers into a string representation with some base.
+//! Bases up to and including 36 can be used for case-insensitive things.
+
 use std::ascii;
 use std::fmt;
 

compiler/rustc_errors/src/markdown/mod.rs

@@ -1,6 +1,7 @@
 //! A simple markdown parser that can write formatted text to the terminal
 //!
 //! Entrypoint is `MdStream::parse_str(...)`
+
 use std::io;
 
 use termcolor::{Buffer, BufferWriter, ColorChoice};

compiler/rustc_expand/src/mbe/macro_check.rs

@@ -104,6 +104,7 @@
 //! Kleene operators under which a meta-variable is repeating is the concatenation of the stacks
 //! stored when entering a macro definition starting from the state in which the meta-variable is
 //! bound.
+
 use crate::errors;
 use crate::mbe::{KleeneToken, TokenTree};
 

compiler/rustc_fs_util/src/lib.rs

@@ -1,9 +1,7 @@
-// tidy-alphabetical-start
 use std::ffi::CString;
 use std::fs;
 use std::io;
 use std::path::{absolute, Path, PathBuf};
-// tidy-alphabetical-end
 
 // Unfortunately, on windows, it looks like msvcrt.dll is silently translating
 // verbatim paths under the hood to non-verbatim paths! This manifests itself as

compiler/rustc_hir_analysis/src/check/dropck.rs

@@ -1,6 +1,7 @@
 // FIXME(@lcnr): Move this module out of `rustc_hir_analysis`.
 //
 // We don't do any drop checking during hir typeck.
+
 use rustc_data_structures::fx::FxHashSet;
 use rustc_errors::{codes::*, struct_span_code_err, ErrorGuaranteed};
 use rustc_infer::infer::outlives::env::OutlivesEnvironment;

compiler/rustc_hir_typeck/src/autoderef.rs

@@ -1,4 +1,5 @@
-//! Some helper functions for `AutoDeref`
+//! Some helper functions for `AutoDeref`.
+
 use super::method::MethodCallee;
 use super::{FnCtxt, PlaceOp};
 

compiler/rustc_hir_typeck/src/errors.rs

@@ -1,4 +1,5 @@
 //! Errors emitted by `rustc_hir_typeck`.
+
 use std::borrow::Cow;
 
 use crate::fluent_generated as fluent;

compiler/rustc_hir_typeck/src/fn_ctxt/inspect_obligations.rs

@@ -1,4 +1,5 @@
 //! A utility module to inspect currently ambiguous obligations in the current context.
+
 use crate::FnCtxt;
 use rustc_infer::traits::{self, ObligationCause};
 use rustc_middle::traits::solve::Goal;

compiler/rustc_infer/src/infer/error_reporting/nice_region_error/named_anon_conflict.rs

@@ -1,5 +1,6 @@
 //! Error Reporting for Anonymous Region Lifetime Errors
 //! where one region is named and the other is anonymous.
+
 use crate::infer::error_reporting::nice_region_error::NiceRegionError;
 use crate::{
     errors::ExplicitLifetimeRequired,

compiler/rustc_infer/src/infer/freshen.rs

@@ -30,6 +30,7 @@
 //! solving a set of constraints. In contrast, the type inferencer assigns a value to each type
 //! variable only once, and it does so as soon as it can, so it is reasonable to ask what the type
 //! inferencer knows "so far".
+
 use super::InferCtxt;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_middle::bug;

compiler/rustc_infer/src/infer/outlives/mod.rs

@@ -1,4 +1,5 @@
 //! Various code related to computing outlives relations.
+
 use self::env::OutlivesEnvironment;
 use super::region_constraints::RegionConstraintData;
 use super::{InferCtxt, RegionResolutionError, SubregionOrigin};

compiler/rustc_lint_defs/src/lib.rs

@@ -1,4 +1,3 @@
-// tidy-alphabetical-start
 pub use self::Level::*;
 use rustc_ast::node_id::NodeId;
 use rustc_ast::{AttrId, Attribute};
@@ -15,7 +14,6 @@ use rustc_span::edition::Edition;
 use rustc_span::symbol::MacroRulesNormalizedIdent;
 use rustc_span::{sym, symbol::Ident, Span, Symbol};
 use rustc_target::spec::abi::Abi;
-// tidy-alphabetical-end
 
 use serde::{Deserialize, Serialize};
 

compiler/rustc_middle/src/middle/privacy.rs

@@ -1,6 +1,7 @@
 //! A pass that checks to make sure private fields and methods aren't used
 //! outside their scopes. This pass will also generate a set of exported items
 //! which are available for use externally when compiled as a library.
+
 use crate::ty::{TyCtxt, Visibility};
 use rustc_data_structures::fx::{FxIndexMap, IndexEntry};
 use rustc_data_structures::stable_hasher::{HashStable, StableHasher};

compiler/rustc_middle/src/mir/statement.rs

@@ -1,4 +1,5 @@
-/// Functionality for statements, operands, places, and things that appear in them.
+//! Functionality for statements, operands, places, and things that appear in them.
+
 use super::{interpret::GlobalAlloc, *};
 
 ///////////////////////////////////////////////////////////////////////////

compiler/rustc_middle/src/mir/terminator.rs

@@ -1,4 +1,5 @@
-/// Functionality for terminators and helper types that appear in terminators.
+//! Functionality for terminators and helper types that appear in terminators.
+
 use rustc_hir::LangItem;
 use smallvec::{smallvec, SmallVec};
 

compiler/rustc_middle/src/ty/abstract_const.rs

@@ -1,4 +1,5 @@
 //! A subset of a mir body used for const evaluability checking.
+
 use crate::ty::{
     self, Const, EarlyBinder, Ty, TyCtxt, TypeFoldable, TypeFolder, TypeSuperFoldable,
     TypeVisitableExt,

compiler/rustc_mir_transform/src/ctfe_limit.rs

@@ -1,5 +1,6 @@
 //! A pass that inserts the `ConstEvalCounter` instruction into any blocks that have a back edge
 //! (thus indicating there is a loop in the CFG), or whose terminator is a function call.
+
 use crate::MirPass;
 
 use rustc_data_structures::graph::dominators::Dominators;

compiler/rustc_mir_transform/src/inline.rs

@@ -1,4 +1,5 @@
-//! Inlining pass for MIR functions
+//! Inlining pass for MIR functions.
+
 use crate::deref_separator::deref_finder;
 use rustc_attr::InlineAttr;
 use rustc_hir::def::DefKind;

compiler/rustc_mir_transform/src/lint.rs

@@ -1,6 +1,7 @@
 //! This pass statically detects code which has undefined behaviour or is likely to be erroneous.
 //! It can be used to locate problems in MIR building or optimizations. It assumes that all code
 //! can be executed, so it has false positives.
+
 use rustc_data_structures::fx::FxHashSet;
 use rustc_index::bit_set::BitSet;
 use rustc_middle::mir::visit::{PlaceContext, Visitor};

compiler/rustc_parse/src/parser/expr.rs

@@ -1,4 +1,5 @@
 // ignore-tidy-filelength
+
 use super::diagnostics::SnapshotParser;
 use super::pat::{CommaRecoveryMode, Expected, RecoverColon, RecoverComma};
 use super::ty::{AllowPlus, RecoverQPath, RecoverReturnSign};

compiler/rustc_pattern_analysis/src/pat.rs

@@ -1,5 +1,6 @@
 //! As explained in [`crate::usefulness`], values and patterns are made from constructors applied to
 //! fields. This file defines types that represent patterns in this way.
+
 use std::fmt;
 
 use smallvec::{smallvec, SmallVec};

compiler/rustc_pattern_analysis/tests/complexity.rs

@@ -1,4 +1,5 @@
 //! Test the pattern complexity limit.
+
 use common::*;
 use rustc_pattern_analysis::{pat::DeconstructedPat, usefulness::PlaceValidity, MatchArm};
 

compiler/rustc_pattern_analysis/tests/exhaustiveness.rs

@@ -1,4 +1,5 @@
 //! Test exhaustiveness checking.
+
 use common::*;
 use rustc_pattern_analysis::{
     pat::{DeconstructedPat, WitnessPat},

compiler/rustc_pattern_analysis/tests/intersection.rs

@@ -1,4 +1,5 @@
 //! Test the computation of arm intersections.
+
 use common::*;
 use rustc_pattern_analysis::{pat::DeconstructedPat, usefulness::PlaceValidity, MatchArm};
 

compiler/rustc_sanitizers/src/cfi/typeid/itanium_cxx_abi/encode.rs

@@ -4,6 +4,7 @@
 //!
 //! For more information about LLVM CFI and cross-language LLVM CFI support for the Rust compiler,
 //! see design document in the tracking issue #89653.
+
 use rustc_data_structures::base_n::ToBaseN;
 use rustc_data_structures::base_n::ALPHANUMERIC_ONLY;
 use rustc_data_structures::base_n::CASE_INSENSITIVE;

compiler/rustc_sanitizers/src/cfi/typeid/itanium_cxx_abi/mod.rs

@@ -3,6 +3,7 @@
 //!
 //! For more information about LLVM CFI and cross-language LLVM CFI support for the Rust compiler,
 //! see design document in the tracking issue #89653.
+
 use rustc_data_structures::fx::FxHashMap;
 use rustc_middle::bug;
 use rustc_middle::ty::{self, Instance, Ty, TyCtxt, TypeFoldable};

compiler/rustc_sanitizers/src/cfi/typeid/itanium_cxx_abi/transform.rs

@@ -3,6 +3,7 @@
 //!
 //! For more information about LLVM CFI and cross-language LLVM CFI support for the Rust compiler,
 //! see design document in the tracking issue #89653.
+
 use rustc_hir as hir;
 use rustc_hir::LangItem;
 use rustc_middle::bug;

compiler/rustc_sanitizers/src/cfi/typeid/mod.rs

@@ -3,6 +3,7 @@
 //!
 //! For more information about LLVM CFI and cross-language LLVM CFI support for the Rust compiler,
 //! see design document in the tracking issue #89653.
+
 use bitflags::bitflags;
 use rustc_middle::ty::{Instance, Ty, TyCtxt};
 use rustc_target::abi::call::FnAbi;

compiler/rustc_sanitizers/src/kcfi/typeid/mod.rs

@@ -3,6 +3,7 @@
 //!
 //! For more information about LLVM KCFI and cross-language LLVM KCFI support for the Rust compiler,
 //! see the tracking issue #123479.
+
 use rustc_middle::ty::{Instance, InstanceKind, ReifyReason, Ty, TyCtxt};
 use rustc_target::abi::call::FnAbi;
 use std::hash::Hasher;

compiler/rustc_session/src/output.rs

@@ -1,4 +1,5 @@
 //! Related to out filenames of compilation (e.g. binaries).
+
 use crate::config::{self, CrateType, Input, OutFileName, OutputFilenames, OutputType};
 use crate::errors::{
     self, CrateNameDoesNotMatch, CrateNameEmpty, CrateNameInvalid, FileIsNotWriteable,

compiler/rustc_smir/src/rustc_smir/builder.rs

@@ -3,6 +3,7 @@
 //! We first retrieve and monomorphize the rustc body representation, i.e., we generate a
 //! monomorphic body using internal representation.
 //! After that, we convert the internal representation into a stable one.
+
 use crate::rustc_smir::{Stable, Tables};
 use rustc_hir::def::DefKind;
 use rustc_middle::mir;

compiler/rustc_smir/src/rustc_smir/convert/error.rs

@@ -1,6 +1,7 @@
 //! Handle the conversion of different internal errors into a stable version.
 //!
 //! Currently we encode everything as [stable_mir::Error], which is represented as a string.
+
 use crate::rustc_smir::{Stable, Tables};
 use rustc_middle::mir::interpret::AllocError;
 use rustc_middle::ty::layout::LayoutError;

compiler/rustc_target/src/spec/targets/mips64_openwrt_linux_musl.rs

@@ -1,5 +1,5 @@
-/// A target tuple for OpenWrt MIPS64 targets
-///
+//! A target tuple for OpenWrt MIPS64 targets.
+
 use crate::abi::Endian;
 use crate::spec::{base, Target, TargetOptions};
 

compiler/rustc_trait_selection/src/traits/normalize.rs

@@ -1,4 +1,5 @@
 //! Deeply normalize types using the old trait solver.
+
 use super::error_reporting::OverflowCause;
 use super::error_reporting::TypeErrCtxtExt;
 use super::SelectionContext;

compiler/rustc_trait_selection/src/traits/select/confirmation.rs

@@ -6,6 +6,7 @@
 //!
 //! [rustc dev guide]:
 //! https://rustc-dev-guide.rust-lang.org/traits/resolution.html#confirmation
+
 use rustc_ast::Mutability;
 use rustc_data_structures::stack::ensure_sufficient_stack;
 use rustc_hir::lang_items::LangItem;

compiler/stable_mir/src/mir/alloc.rs

@@ -1,4 +1,5 @@
 //! This module provides methods to retrieve allocation information, such as static variables.
+
 use crate::mir::mono::{Instance, StaticDef};
 use crate::target::{Endian, MachineInfo};
 use crate::ty::{Allocation, Binder, ExistentialTraitRef, IndexedVal, Ty};

library/alloc/src/boxed/thin.rs

@@ -1,6 +1,7 @@
-// Based on
-// https://github.com/matthieu-m/rfc2580/blob/b58d1d3cba0d4b5e859d3617ea2d0943aaa31329/examples/thin.rs
-// by matthieu-m
+//! Based on
+//! <https://github.com/matthieu-m/rfc2580/blob/b58d1d3cba0d4b5e859d3617ea2d0943aaa31329/examples/thin.rs>
+//! by matthieu-m
+
 use crate::alloc::{self, Layout, LayoutError};
 use core::error::Error;
 use core::fmt::{self, Debug, Display, Formatter};

library/alloc/src/vec/in_place_collect.rs

@@ -154,6 +154,7 @@
 //! }
 //! vec.truncate(write_idx);
 //! ```
+
 use crate::alloc::{handle_alloc_error, Global};
 use core::alloc::Allocator;
 use core::alloc::Layout;

library/core/src/str/count.rs

@@ -17,6 +17,7 @@
 //! Note: Because the term "leading byte" can sometimes be ambiguous (for
 //! example, it could also refer to the first byte of a slice), we'll often use
 //! the term "non-continuation byte" to refer to these bytes in the code.
+
 use core::intrinsics::unlikely;
 
 const USIZE_SIZE: usize = core::mem::size_of::<usize>();

library/core/tests/iter/adapters/map_windows.rs

@@ -3,6 +3,7 @@ use std::sync::atomic::{AtomicUsize, Ordering::SeqCst};
 #[cfg(not(panic = "abort"))]
 mod drop_checks {
     //! These tests mainly make sure the elements are correctly dropped.
+
     use std::sync::atomic::{AtomicBool, AtomicUsize, Ordering::SeqCst};
 
     #[derive(Debug)]

library/core/tests/net/parser.rs

@@ -1,4 +1,5 @@
 // FIXME: These tests are all excellent candidates for AFL fuzz testing
+
 use core::net::{IpAddr, Ipv4Addr, Ipv6Addr, SocketAddr, SocketAddrV4, SocketAddrV6};
 use core::str::FromStr;
 

library/core/tests/num/ieee754.rs

@@ -27,6 +27,7 @@
 //! standard. That is why they accept wildly diverse inputs or may seem to duplicate other tests.
 //! Please consider this carefully when adding, removing, or reorganizing these tests. They are
 //! here so that it is clear what tests are required by the standard and what can be changed.
+
 use ::core::str::FromStr;
 
 // IEEE 754 for many tests is applied to specific bit patterns.

library/core/tests/pin_macro.rs

@@ -1,4 +1,5 @@
 // edition:2021
+
 use core::{
     marker::PhantomPinned,
     mem::{drop as stuff, transmute},

library/panic_unwind/src/miri.rs

@@ -1,4 +1,5 @@
 //! Unwinding panics for Miri.
+
 use alloc::boxed::Box;
 use core::any::Any;
 

library/portable-simd/crates/core_simd/examples/dot_product.rs

@@ -1,6 +1,5 @@
-// Code taken from the `packed_simd` crate
-// Run this code with `cargo test --example dot_product`
-//use std::iter::zip;
+//! Code taken from the `packed_simd` crate.
+//! Run this code with `cargo test --example dot_product`.
 
 #![feature(array_chunks)]
 #![feature(slice_as_chunks)]

library/portable-simd/crates/core_simd/src/ops/assign.rs

@@ -1,4 +1,5 @@
 //! Assignment operators
+
 use super::*;
 use core::ops::{AddAssign, MulAssign}; // commutative binary op-assignment
 use core::ops::{BitAndAssign, BitOrAssign, BitXorAssign}; // commutative bit binary op-assignment

library/portable-simd/crates/core_simd/src/ops/deref.rs

@@ -2,6 +2,7 @@
 //! Ideally, Rust would take care of this itself,
 //! and method calls usually handle the LHS implicitly.
 //! But this is not the case with arithmetic ops.
+
 use super::*;
 
 macro_rules! deref_lhs {

library/std/src/hash/random.rs

@@ -6,6 +6,7 @@
 //! outside this crate.
 //!
 //! [`collections`]: crate::collections
+
 #[allow(deprecated)]
 use super::{BuildHasher, Hasher, SipHasher13};
 use crate::cell::Cell;