Auto merge of rust-lang#117772 - surechen:for_117448, r=petrochenkov

Tracking import use types for more accurate redundant import checking

fixes rust-lang#117448

By tracking import use types to check whether it is scope uses or the other situations like module-relative uses,  we can do more accurate redundant import checking.

For example unnecessary imports in std::prelude that can be eliminated:

```rust
use std::option::Option::Some;//~ WARNING the item `Some` is imported redundantly
use std::option::Option::None; //~ WARNING the item `None` is imported redundantly
```

Author: bors

crates/hir-def/src/body/pretty.rs

@@ -6,7 +6,7 @@ use itertools::Itertools;
 
 use crate::{
     hir::{
-        Array, BindingAnnotation, BindingId, CaptureBy, ClosureKind, Literal, LiteralOrConst,
+        Array, BindingAnnotation, CaptureBy, ClosureKind, Literal, LiteralOrConst,
         Movability, Statement,
     },
     pretty::{print_generic_args, print_path, print_type_ref},

crates/hir-def/src/import_map.rs

@@ -3,7 +3,7 @@
 use std::{fmt, hash::BuildHasherDefault};
 
 use base_db::CrateId;
-use fst::{self, raw::IndexedValue, Automaton, Streamer};
+use fst::{raw::IndexedValue, Automaton, Streamer};
 use hir_expand::name::Name;
 use indexmap::IndexMap;
 use itertools::Itertools;

crates/hir-def/src/item_tree/lower.rs

@@ -2,12 +2,12 @@
 
 use std::collections::hash_map::Entry;
 
-use hir_expand::{ast_id_map::AstIdMap, span_map::SpanMapRef, HirFileId};
-use syntax::ast::{self, HasModuleItem, HasTypeBounds, IsString};
+use hir_expand::{ast_id_map::AstIdMap, span_map::SpanMapRef};
+use syntax::ast::{HasModuleItem, HasTypeBounds, IsString};
 
 use crate::{
-    generics::{GenericParams, GenericParamsCollector, TypeParamData, TypeParamProvenance},
-    type_ref::{LifetimeRef, TraitBoundModifier, TraitRef},
+    generics::{GenericParamsCollector, TypeParamData, TypeParamProvenance},
+    type_ref::{LifetimeRef, TraitBoundModifier},
     LocalLifetimeParamId, LocalTypeOrConstParamId,
 };
 

crates/hir-def/src/item_tree/pretty.rs

@@ -1,13 +1,12 @@
 //! `ItemTree` debug printer.
 
-use std::fmt::{self, Write};
+use std::fmt::Write;
 
 use span::ErasedFileAstId;
 
 use crate::{
-    generics::{TypeOrConstParamData, WherePredicate, WherePredicateTypeTarget},
+    generics::{WherePredicate, WherePredicateTypeTarget},
     pretty::{print_path, print_type_bounds, print_type_ref},
-    visibility::RawVisibility,
 };
 
 use super::*;

crates/hir-def/src/nameres.rs

@@ -57,7 +57,7 @@ pub mod proc_macro;
 #[cfg(test)]
 mod tests;
 
-use std::{cmp::Ord, ops::Deref};
+use std::ops::Deref;
 
 use base_db::{CrateId, Edition, FileId};
 use hir_expand::{

crates/hir-ty/src/diagnostics/match_check/pat_util.rs

@@ -2,7 +2,7 @@
 //!
 //! Originates from `rustc_hir::pat_util`
 
-use std::iter::{Enumerate, ExactSizeIterator};
+use std::iter::Enumerate;
 
 pub(crate) struct EnumerateAndAdjust<I> {
     enumerate: Enumerate<I>,

crates/hir-ty/src/mir/eval/shim.rs

@@ -4,11 +4,7 @@
 use std::cmp;
 
 use chalk_ir::TyKind;
-use hir_def::{
-    builtin_type::{BuiltinInt, BuiltinUint},
-    resolver::HasResolver,
-};
-use hir_expand::mod_path::ModPath;
+use hir_def::builtin_type::{BuiltinInt, BuiltinUint};
 
 use super::*;
 

crates/hir-ty/src/mir/lower.rs

@@ -1,6 +1,6 @@
 //! This module generates a polymorphic MIR from a hir body
 
-use std::{fmt::Write, iter, mem};
+use std::{fmt::Write, mem};
 
 use base_db::{salsa::Cycle, FileId};
 use chalk_ir::{BoundVar, ConstData, DebruijnIndex, TyKind};
@@ -14,23 +14,19 @@ use hir_def::{
     lang_item::{LangItem, LangItemTarget},
     path::Path,
     resolver::{resolver_for_expr, HasResolver, ResolveValueResult, ValueNs},
-    AdtId, DefWithBodyId, EnumVariantId, GeneralConstId, HasModule, ItemContainerId, LocalFieldId,
+    AdtId, EnumVariantId, GeneralConstId, HasModule, ItemContainerId, LocalFieldId,
     Lookup, TraitId, TupleId, TypeOrConstParamId,
 };
 use hir_expand::name::Name;
-use la_arena::ArenaMap;
-use rustc_hash::FxHashMap;
 use syntax::TextRange;
 use triomphe::Arc;
 
 use crate::{
     consteval::ConstEvalError,
-    db::{HirDatabase, InternedClosure},
-    display::HirDisplay,
+    db::InternedClosure,
     infer::{CaptureKind, CapturedItem, TypeMismatch},
     inhabitedness::is_ty_uninhabited_from,
     layout::LayoutError,
-    mapping::ToChalk,
     static_lifetime,
     traits::FnTrait,
     utils::{generics, ClosureSubst},

crates/hir-ty/src/mir/lower/pattern_matching.rs

@@ -1,6 +1,6 @@
 //! MIR lowering for patterns
 
-use hir_def::{hir::LiteralOrConst, resolver::HasResolver, AssocItemId};
+use hir_def::AssocItemId;
 
 use crate::BindingMode;
 

crates/ide-assists/src/handlers/generate_delegate_methods.rs

@@ -1,4 +1,4 @@
-use hir::{self, HasCrate, HasVisibility};
+use hir::{HasCrate, HasVisibility};
 use ide_db::{path_transform::PathTransform, FxHashSet};
 use syntax::{
     ast::{

crates/ide-completion/src/completions/item_list/trait_impl.rs

@@ -31,7 +31,7 @@
 //! }
 //! ```
 
-use hir::{self, HasAttrs};
+use hir::HasAttrs;
 use ide_db::{
     documentation::HasDocs, path_transform::PathTransform,
     syntax_helpers::insert_whitespace_into_node, traits::get_missing_assoc_items, SymbolKind,

crates/ide-db/src/symbol_index.rs

@@ -31,7 +31,7 @@ use base_db::{
     salsa::{self, ParallelDatabase},
     SourceDatabaseExt, SourceRootId, Upcast,
 };
-use fst::{self, raw::IndexedValue, Automaton, Streamer};
+use fst::{raw::IndexedValue, Automaton, Streamer};
 use hir::{
     db::HirDatabase,
     import_map::{AssocSearchMode, SearchMode},

crates/rust-analyzer/src/cargo_target_spec.rs

@@ -4,7 +4,7 @@ use std::mem;
 
 use cfg::{CfgAtom, CfgExpr};
 use ide::{Cancellable, CrateId, FileId, RunnableKind, TestId};
-use project_model::{self, CargoFeatures, ManifestPath, TargetKind};
+use project_model::{CargoFeatures, ManifestPath, TargetKind};
 use rustc_hash::FxHashSet;
 use vfs::AbsPathBuf;
 

crates/rust-analyzer/src/cli/lsif.rs

@@ -13,7 +13,7 @@ use ide_db::{
     LineIndexDatabase,
 };
 use load_cargo::{load_workspace, LoadCargoConfig, ProcMacroServerChoice};
-use lsp_types::{self, lsif};
+use lsp_types::lsif;
 use project_model::{CargoConfig, ProjectManifest, ProjectWorkspace, RustLibSource};
 use rustc_hash::FxHashMap;
 use vfs::{AbsPathBuf, Vfs};

crates/salsa/salsa-macros/src/query_group.rs

@@ -1,5 +1,4 @@
 //!
-use std::{convert::TryFrom, iter::FromIterator};
 
 use crate::parenthesized::Parenthesized;
 use heck::ToUpperCamelCase;

crates/salsa/src/debug.rs

@@ -5,7 +5,6 @@ use crate::durability::Durability;
 use crate::plumbing::QueryStorageOps;
 use crate::Query;
 use crate::QueryTable;
-use std::iter::FromIterator;
 
 /// Additional methods on queries that can be used to "peek into"
 /// their current state. These methods are meant for debugging and

crates/salsa/src/derived.rs

@@ -13,7 +13,6 @@ use crate::Runtime;
 use crate::{Database, DatabaseKeyIndex, QueryDb, Revision};
 use parking_lot::RwLock;
 use std::borrow::Borrow;
-use std::convert::TryFrom;
 use std::hash::Hash;
 use std::marker::PhantomData;
 use triomphe::Arc;

crates/salsa/src/input.rs

@@ -14,7 +14,6 @@ use crate::Runtime;
 use crate::{DatabaseKeyIndex, QueryDb};
 use indexmap::map::Entry;
 use parking_lot::RwLock;
-use std::convert::TryFrom;
 use std::iter;
 use tracing::debug;
 

crates/salsa/src/interned.rs

@@ -13,7 +13,6 @@ use crate::{Database, DatabaseKeyIndex, QueryDb};
 use parking_lot::RwLock;
 use rustc_hash::FxHashMap;
 use std::collections::hash_map::Entry;
-use std::convert::From;
 use std::fmt::Debug;
 use std::hash::Hash;
 use triomphe::Arc;