Simplify use crate::rustc_foo::bar occurrences.

They can just be written as `use rustc_foo::bar`, which is far more
standard. (I didn't even know that a `crate::` prefix was valid.)

Author: nnethercote

compiler/rustc_codegen_gcc/src/debuginfo.rs

@@ -1,10 +1,9 @@
-use crate::rustc_index::Idx;
 use gccjit::{Location, RValue};
 use rustc_codegen_ssa::mir::debuginfo::{DebugScope, FunctionDebugContext, VariableKind};
 use rustc_codegen_ssa::traits::{DebugInfoBuilderMethods, DebugInfoMethods};
 use rustc_data_structures::sync::Lrc;
 use rustc_index::bit_set::BitSet;
-use rustc_index::IndexVec;
+use rustc_index::{Idx, IndexVec};
 use rustc_middle::mir::{self, Body, SourceScope};
 use rustc_middle::ty::{Instance, PolyExistentialTraitRef, Ty};
 use rustc_session::config::DebugInfo;

compiler/rustc_codegen_gcc/src/type_of.rs

@@ -1,7 +1,7 @@
 use std::fmt::Write;
 
-use crate::rustc_codegen_ssa::traits::{BaseTypeMethods, DerivedTypeMethods, LayoutTypeMethods};
 use gccjit::{Struct, Type};
+use rustc_codegen_ssa::traits::{BaseTypeMethods, DerivedTypeMethods, LayoutTypeMethods};
 use rustc_middle::bug;
 use rustc_middle::ty::layout::{LayoutOf, TyAndLayout};
 use rustc_middle::ty::print::with_no_trimmed_paths;
@@ -205,7 +205,7 @@ impl<'tcx> LayoutGccExt<'tcx> for TyAndLayout<'tcx> {
     /// of that field's type - this is useful for taking the address of
     /// that field and ensuring the struct has the right alignment.
     fn gcc_type<'gcc>(&self, cx: &CodegenCx<'gcc, 'tcx>) -> Type<'gcc> {
-        use crate::rustc_middle::ty::layout::FnAbiOf;
+        use rustc_middle::ty::layout::FnAbiOf;
         // This must produce the same result for `repr(transparent)` wrappers as for the inner type!
         // In other words, this should generally not look at the type at all, but only at the
         // layout.

compiler/rustc_hir_typeck/src/fn_ctxt/inspect_obligations.rs

@@ -1,9 +1,8 @@
 //! A utility module to inspect currently ambiguous obligations in the current context.
-use crate::rustc_middle::ty::TypeVisitableExt;
 use crate::FnCtxt;
 use rustc_infer::traits::solve::Goal;
 use rustc_infer::traits::{self, ObligationCause};
-use rustc_middle::ty::{self, Ty};
+use rustc_middle::ty::{self, Ty, TypeVisitableExt};
 use rustc_span::Span;
 use rustc_trait_selection::solve::inspect::ProofTreeInferCtxtExt;
 use rustc_trait_selection::solve::inspect::{InspectConfig, InspectGoal, ProofTreeVisitor};

compiler/rustc_hir_typeck/src/fn_ctxt/suggestions.rs

@@ -6,7 +6,6 @@ use crate::fn_ctxt::rustc_span::BytePos;
 use crate::hir::is_range_literal;
 use crate::method::probe;
 use crate::method::probe::{IsSuggestion, Mode, ProbeScope};
-use crate::rustc_middle::ty::Article;
 use core::cmp::min;
 use core::iter;
 use hir::def_id::LocalDefId;
@@ -28,7 +27,7 @@ use rustc_middle::lint::in_external_macro;
 use rustc_middle::middle::stability::EvalResult;
 use rustc_middle::ty::print::with_no_trimmed_paths;
 use rustc_middle::ty::{
-    self, suggest_constraining_type_params, Binder, IsSuggestable, ToPredicate, Ty,
+    self, suggest_constraining_type_params, Article, Binder, IsSuggestable, ToPredicate, Ty,
     TypeVisitableExt,
 };
 use rustc_session::errors::ExprParenthesesNeeded;

compiler/rustc_mir_transform/src/large_enums.rs

@@ -1,7 +1,7 @@
-use crate::rustc_middle::ty::util::IntTypeExt;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_middle::mir::interpret::AllocId;
 use rustc_middle::mir::*;
+use rustc_middle::ty::util::IntTypeExt;
 use rustc_middle::ty::{self, AdtDef, ParamEnv, Ty, TyCtxt};
 use rustc_session::Session;
 use rustc_target::abi::{HasDataLayout, Size, TagEncoding, Variants};

compiler/rustc_query_impl/src/plumbing.rs

@@ -2,8 +2,6 @@
 //! generate the actual methods on tcx which find and execute the provider,
 //! manage the caches, and so forth.
 
-use crate::rustc_middle::dep_graph::DepContext;
-use crate::rustc_middle::ty::TyEncoder;
 use crate::QueryConfigRestored;
 use rustc_data_structures::stable_hasher::{Hash64, HashStable, StableHasher};
 use rustc_data_structures::sync::Lock;
@@ -13,14 +11,14 @@ use rustc_errors::DiagInner;
 use rustc_index::Idx;
 use rustc_middle::dep_graph::dep_kinds;
 use rustc_middle::dep_graph::{
-    self, DepKind, DepKindStruct, DepNode, DepNodeIndex, SerializedDepNodeIndex,
+    self, DepContext, DepKind, DepKindStruct, DepNode, DepNodeIndex, SerializedDepNodeIndex,
 };
 use rustc_middle::query::on_disk_cache::AbsoluteBytePos;
 use rustc_middle::query::on_disk_cache::{CacheDecoder, CacheEncoder, EncodedDepNodeIndex};
 use rustc_middle::query::Key;
 use rustc_middle::ty::print::with_reduced_queries;
 use rustc_middle::ty::tls::{self, ImplicitCtxt};
-use rustc_middle::ty::{self, TyCtxt};
+use rustc_middle::ty::{self, TyCtxt, TyEncoder};
 use rustc_query_system::dep_graph::{DepNodeParams, HasDepContext};
 use rustc_query_system::ich::StableHashingContext;
 use rustc_query_system::query::{

src/librustdoc/clean/mod.rs

@@ -1860,9 +1860,9 @@ fn normalize<'tcx>(
         return None;
     }
 
-    use crate::rustc_trait_selection::infer::TyCtxtInferExt;
-    use crate::rustc_trait_selection::traits::query::normalize::QueryNormalizeExt;
     use rustc_middle::traits::ObligationCause;
+    use rustc_trait_selection::infer::TyCtxtInferExt;
+    use rustc_trait_selection::traits::query::normalize::QueryNormalizeExt;
 
     // Try to normalize `<X as Y>::T` to a type
     let infcx = cx.tcx.infer_ctxt().build();

src/librustdoc/externalfiles.rs

@@ -1,5 +1,5 @@
 use crate::html::markdown::{ErrorCodes, HeadingOffset, IdMap, Markdown, Playground};
-use crate::rustc_span::edition::Edition;
+use rustc_span::edition::Edition;
 use std::fs;
 use std::path::Path;
 use std::str;

src/librustdoc/html/format.rs

@@ -594,9 +594,9 @@ fn generate_item_def_id_path(
     root_path: Option<&str>,
     original_def_kind: DefKind,
 ) -> Result<(String, ItemType, Vec<Symbol>), HrefError> {
-    use crate::rustc_trait_selection::infer::TyCtxtInferExt;
-    use crate::rustc_trait_selection::traits::query::normalize::QueryNormalizeExt;
     use rustc_middle::traits::ObligationCause;
+    use rustc_trait_selection::infer::TyCtxtInferExt;
+    use rustc_trait_selection::traits::query::normalize::QueryNormalizeExt;
 
     let tcx = cx.tcx();
     let crate_name = tcx.crate_name(def_id.krate);

src/tools/clippy/clippy_lints/src/manual_assert.rs

@@ -1,10 +1,9 @@
-use crate::rustc_lint::LintContext;
 use clippy_utils::diagnostics::span_lint_and_then;
 use clippy_utils::macros::{is_panic, root_macro_call};
 use clippy_utils::{is_else_clause, is_parent_stmt, peel_blocks_with_stmt, span_extract_comment, sugg};
 use rustc_errors::Applicability;
 use rustc_hir::{Expr, ExprKind, UnOp};
-use rustc_lint::{LateContext, LateLintPass};
+use rustc_lint::{LateContext, LateLintPass, LintContext};
 use rustc_session::declare_lint_pass;
 
 declare_clippy_lint! {