diff --git a/src/libcore/num/mod.rs b/src/libcore/num/mod.rs
index 4f3c12567095e..33d53892c55b2 100644
--- a/src/libcore/num/mod.rs
+++ b/src/libcore/num/mod.rs
@@ -16,7 +16,7 @@
use self::wrapping::OverflowingOps;
use char::CharExt;
-use cmp::{Eq, PartialOrd};
+use cmp::PartialOrd;
use convert::From;
use fmt;
use intrinsics;
diff --git a/src/libcore/option.rs b/src/libcore/option.rs
index aca36d856266b..60b3ed0f6ddf3 100644
--- a/src/libcore/option.rs
+++ b/src/libcore/option.rs
@@ -146,7 +146,6 @@
use self::Option::*;
use clone::Clone;
-use cmp::{Eq, Ord};
use default::Default;
use iter::ExactSizeIterator;
use iter::{Iterator, DoubleEndedIterator, FromIterator, IntoIterator};
diff --git a/src/libcore/str/mod.rs b/src/libcore/str/mod.rs
index 7aacdbeb76879..101afa21d2742 100644
--- a/src/libcore/str/mod.rs
+++ b/src/libcore/str/mod.rs
@@ -19,7 +19,6 @@ use self::pattern::{Searcher, ReverseSearcher, DoubleEndedSearcher};
use char::{self, CharExt};
use clone::Clone;
-use cmp::Eq;
use convert::AsRef;
use default::Default;
use fmt;
@@ -1180,7 +1179,6 @@ Section: Trait implementations
mod traits {
use cmp::{self, Ordering, Ord, PartialEq, PartialOrd, Eq};
use cmp::Ordering::{Less, Greater};
- use iter::Iterator;
use option::Option;
use option::Option::Some;
use ops;
diff --git a/src/librustc/lint/context.rs b/src/librustc/lint/context.rs
index 1ed873f0508d5..56baf9ab6d956 100644
--- a/src/librustc/lint/context.rs
+++ b/src/librustc/lint/context.rs
@@ -29,7 +29,7 @@ use middle::privacy::AccessLevels;
use middle::ty::{self, Ty};
use session::{early_error, Session};
use lint::{Level, LevelSource, Lint, LintId, LintArray, LintPass};
-use lint::{EarlyLintPass, EarlyLintPassObject, LateLintPass, LateLintPassObject};
+use lint::{EarlyLintPassObject, LateLintPass, LateLintPassObject};
use lint::{Default, CommandLine, Node, Allow, Warn, Deny, Forbid};
use lint::builtin;
use util::nodemap::FnvHashMap;
diff --git a/src/librustc/middle/dead.rs b/src/librustc/middle/dead.rs
index ec1b447d7111b..4afa0e301465f 100644
--- a/src/librustc/middle/dead.rs
+++ b/src/librustc/middle/dead.rs
@@ -22,7 +22,7 @@ use lint;
use std::collections::HashSet;
use syntax::{ast, codemap};
-use syntax::attr::{self, AttrMetaMethods};
+use syntax::attr;
// Any local node that may call something in its body block should be
// explored. For example, if it's a live NodeItem that is a
diff --git a/src/librustc/middle/implicator.rs b/src/librustc/middle/implicator.rs
index 9f33c4df03d41..6c24134f5a558 100644
--- a/src/librustc/middle/implicator.rs
+++ b/src/librustc/middle/implicator.rs
@@ -15,7 +15,7 @@ use middle::infer::{InferCtxt, GenericKind};
use middle::subst::Substs;
use middle::traits;
use middle::ty::{self, RegionEscape, ToPredicate, Ty};
-use middle::ty::fold::{TypeFoldable, TypeFolder};
+use middle::ty::fold::TypeFoldable;
use syntax::ast;
use syntax::codemap::Span;
diff --git a/src/librustc/middle/infer/combine.rs b/src/librustc/middle/infer/combine.rs
index 03554a59655b1..d455b1a4fa6f6 100644
--- a/src/librustc/middle/infer/combine.rs
+++ b/src/librustc/middle/infer/combine.rs
@@ -46,7 +46,7 @@ use middle::ty::{IntType, UintType};
use middle::ty::{self, Ty};
use middle::ty::error::TypeError;
use middle::ty::fold::{TypeFolder, TypeFoldable};
-use middle::ty::relate::{Relate, RelateResult, TypeRelation};
+use middle::ty::relate::{RelateResult, TypeRelation};
use syntax::ast;
use syntax::codemap::Span;
diff --git a/src/librustc/middle/infer/mod.rs b/src/librustc/middle/infer/mod.rs
index b39ddfe95c83a..25dde6739c1e9 100644
--- a/src/librustc/middle/infer/mod.rs
+++ b/src/librustc/middle/infer/mod.rs
@@ -33,7 +33,7 @@ use middle::ty::adjustment;
use middle::ty::{TyVid, IntVid, FloatVid, RegionVid};
use middle::ty::{self, Ty, HasTypeFlags};
use middle::ty::error::{ExpectedFound, TypeError, UnconstrainedNumeric};
-use middle::ty::fold::{TypeFolder, TypeFoldable};
+use middle::ty::fold::TypeFoldable;
use middle::ty::relate::{Relate, RelateResult, TypeRelation};
use rustc_data_structures::unify::{self, UnificationTable};
use std::cell::{RefCell, Ref};
diff --git a/src/librustc/middle/ty/context.rs b/src/librustc/middle/ty/context.rs
index cee651743ca86..5e0cc5131bcc0 100644
--- a/src/librustc/middle/ty/context.rs
+++ b/src/librustc/middle/ty/context.rs
@@ -271,6 +271,7 @@ pub struct ctxt<'tcx> {
pub map: ast_map::Map<'tcx>,
pub freevars: RefCell<FreevarMap>,
+ pub maybe_unused_trait_imports: NodeSet,
pub tcache: RefCell<DefIdMap<ty::TypeScheme<'tcx>>>,
pub rcache: RefCell<FnvHashMap<ty::CReaderCacheKey, Ty<'tcx>>>,
pub tc_cache: RefCell<FnvHashMap<Ty<'tcx>, ty::contents::TypeContents>>,
@@ -306,6 +307,10 @@ pub struct ctxt<'tcx> {
/// about.
pub used_mut_nodes: RefCell<NodeSet>,
+ /// Set of trait imports actually used in method resolution.
+ /// This is used for warning unused imports.
+ pub used_trait_imports: RefCell<NodeSet>,
+
/// The set of external nominal types whose implementations have been read.
/// This is used for lazy resolution of methods.
pub populated_external_types: RefCell<DefIdSet>,
@@ -475,6 +480,7 @@ impl<'tcx> ctxt<'tcx> {
named_region_map: resolve_lifetime::NamedRegionMap,
map: ast_map::Map<'tcx>,
freevars: FreevarMap,
+ maybe_unused_trait_imports: NodeSet,
region_maps: RegionMaps,
lang_items: middle::lang_items::LanguageItems,
stability: stability::Index<'tcx>,
@@ -508,6 +514,7 @@ impl<'tcx> ctxt<'tcx> {
fulfilled_predicates: RefCell::new(traits::FulfilledPredicates::new()),
map: map,
freevars: RefCell::new(freevars),
+ maybe_unused_trait_imports: maybe_unused_trait_imports,
tcache: RefCell::new(DefIdMap()),
rcache: RefCell::new(FnvHashMap()),
tc_cache: RefCell::new(FnvHashMap()),
@@ -522,6 +529,7 @@ impl<'tcx> ctxt<'tcx> {
impl_items: RefCell::new(DefIdMap()),
used_unsafe: RefCell::new(NodeSet()),
used_mut_nodes: RefCell::new(NodeSet()),
+ used_trait_imports: RefCell::new(NodeSet()),
populated_external_types: RefCell::new(DefIdSet()),
populated_external_primitive_impls: RefCell::new(DefIdSet()),
extern_const_statics: RefCell::new(DefIdMap()),
diff --git a/src/librustc/middle/ty/mod.rs b/src/librustc/middle/ty/mod.rs
index 7477c4dead031..5dc539ea882c7 100644
--- a/src/librustc/middle/ty/mod.rs
+++ b/src/librustc/middle/ty/mod.rs
@@ -29,14 +29,13 @@ use middle::lang_items::{FnTraitLangItem, FnMutTraitLangItem, FnOnceTraitLangIte
use middle::subst::{self, ParamSpace, Subst, Substs, VecPerParamSpace};
use middle::traits;
use middle::ty;
-use middle::ty::fold::TypeFolder;
use middle::ty::walk::TypeWalker;
use util::common::memoized;
use util::nodemap::{NodeMap, NodeSet, DefIdMap};
use util::nodemap::FnvHashMap;
use serialize::{Encodable, Encoder, Decodable, Decoder};
-use std::borrow::{Borrow, Cow};
+use std::borrow::Cow;
use std::cell::{Cell, RefCell};
use std::hash::{Hash, Hasher};
use std::iter;
@@ -2752,8 +2751,13 @@ pub type FreevarMap = NodeMap<Vec<Freevar>>;
pub type CaptureModeMap = NodeMap<hir::CaptureClause>;
+pub struct TraitCandidate {
+ pub def_id: DefId,
+ pub import_id: Option<NodeId>,
+}
+
// Trait method resolution
-pub type TraitMap = NodeMap<Vec<DefId>>;
+pub type TraitMap = NodeMap<Vec<TraitCandidate>>;
// Map from the NodeId of a glob import to a list of items which are actually
// imported.
diff --git a/src/librustc/middle/ty/util.rs b/src/librustc/middle/ty/util.rs
index 0517769356f75..f183f3a0b6076 100644
--- a/src/librustc/middle/ty/util.rs
+++ b/src/librustc/middle/ty/util.rs
@@ -28,7 +28,7 @@ use std::cmp;
use std::hash::{Hash, SipHasher, Hasher};
use std::rc::Rc;
use syntax::ast::{self, Name};
-use syntax::attr::{self, AttrMetaMethods, SignedInt, UnsignedInt};
+use syntax::attr::{self, SignedInt, UnsignedInt};
use syntax::codemap::Span;
use rustc_front::hir;
diff --git a/src/librustc/session/filesearch.rs b/src/librustc/session/filesearch.rs
index 09c6b54d99cf8..7749cbd238599 100644
--- a/src/librustc/session/filesearch.rs
+++ b/src/librustc/session/filesearch.rs
@@ -15,7 +15,6 @@ pub use self::FileMatch::*;
use std::collections::HashSet;
use std::env;
use std::fs;
-use std::io::prelude::*;
use std::path::{Path, PathBuf};
use session::search_paths::{SearchPaths, PathKind};
diff --git a/src/librustc_driver/driver.rs b/src/librustc_driver/driver.rs
index 69e065b3e8f97..7541e752fbbaa 100644
--- a/src/librustc_driver/driver.rs
+++ b/src/librustc_driver/driver.rs
@@ -703,6 +703,7 @@ pub fn phase_3_run_analysis_passes<'tcx, F, R>(sess: &'tcx Session,
let resolve::CrateMap {
def_map,
freevars,
+ maybe_unused_trait_imports,
export_map,
trait_map,
external_exports,
@@ -741,6 +742,7 @@ pub fn phase_3_run_analysis_passes<'tcx, F, R>(sess: &'tcx Session,
named_region_map,
ast_map,
freevars,
+ maybe_unused_trait_imports,
region_map,
lang_items,
stability::Index::new(krate),
diff --git a/src/librustc_driver/test.rs b/src/librustc_driver/test.rs
index 2fb23c943c76a..124b3192d9b19 100644
--- a/src/librustc_driver/test.rs
+++ b/src/librustc_driver/test.rs
@@ -128,7 +128,7 @@ fn test_env<F>(source_string: &str,
// run just enough stuff to build a tcx:
let lang_items = lang_items::collect_language_items(&sess, &ast_map);
- let resolve::CrateMap { def_map, freevars, .. } =
+ let resolve::CrateMap { def_map, freevars, maybe_unused_trait_imports, .. } =
resolve::resolve_crate(&sess, &ast_map, resolve::MakeGlobMap::No);
let named_region_map = resolve_lifetime::krate(&sess, krate, &def_map.borrow());
let region_map = region::resolve_crate(&sess, krate);
@@ -138,6 +138,7 @@ fn test_env<F>(source_string: &str,
named_region_map,
ast_map,
freevars,
+ maybe_unused_trait_imports,
region_map,
lang_items,
stability::Index::new(krate),
diff --git a/src/librustc_lint/types.rs b/src/librustc_lint/types.rs
index a1d029025b2fa..b963329049d9e 100644
--- a/src/librustc_lint/types.rs
+++ b/src/librustc_lint/types.rs
@@ -22,7 +22,7 @@ use std::cmp;
use std::{i8, i16, i32, i64, u8, u16, u32, u64, f32, f64};
use syntax::{abi, ast};
-use syntax::attr::{self, AttrMetaMethods};
+use syntax::attr;
use syntax::codemap::{self, Span};
use syntax::feature_gate::{emit_feature_err, GateIssue};
use syntax::ast::{TyIs, TyUs, TyI8, TyU8, TyI16, TyU16, TyI32, TyU32, TyI64, TyU64};
diff --git a/src/librustc_metadata/encoder.rs b/src/librustc_metadata/encoder.rs
index a627eeb688075..c9ce36ae2122b 100644
--- a/src/librustc_metadata/encoder.rs
+++ b/src/librustc_metadata/encoder.rs
@@ -43,7 +43,6 @@ use std::u32;
use syntax::abi;
use syntax::ast::{self, NodeId, Name, CRATE_NODE_ID, CrateNum};
use syntax::attr;
-use syntax::attr::AttrMetaMethods;
use syntax::diagnostic::SpanHandler;
use syntax::parse::token::special_idents;
use syntax;
diff --git a/src/librustc_resolve/check_unused.rs b/src/librustc_resolve/check_unused.rs
index 7f740f9c03335..ceed90059628a 100644
--- a/src/librustc_resolve/check_unused.rs
+++ b/src/librustc_resolve/check_unused.rs
@@ -16,6 +16,8 @@
// resolve data structures and because it finalises the privacy information for
// `use` directives.
//
+// Unused trait imports can't be checked until the method resolution. We save
+// candidates here, and do the actual check in librustc_typeck/check_unused.rs.
use std::ops::{Deref, DerefMut};
@@ -62,13 +64,7 @@ impl<'a, 'b, 'tcx> UnusedImportCheckVisitor<'a, 'b, 'tcx> {
debug!("finalizing import uses for {:?}",
self.session.codemap().span_to_snippet(span));
- if !self.used_imports.contains(&(id, TypeNS)) &&
- !self.used_imports.contains(&(id, ValueNS)) {
- self.session.add_lint(lint::builtin::UNUSED_IMPORTS,
- id,
- span,
- "unused import".to_string());
- }
+ self.check_import(id, span);
let mut def_map = self.def_map.borrow_mut();
let path_res = if let Some(r) = def_map.get_mut(&id) {
@@ -109,6 +105,24 @@ impl<'a, 'b, 'tcx> UnusedImportCheckVisitor<'a, 'b, 'tcx> {
type_used: t_used,
};
}
+
+ fn check_import(&mut self, id: ast::NodeId, span: Span) {
+ if !self.used_imports.contains(&(id, TypeNS)) &&
+ !self.used_imports.contains(&(id, ValueNS)) {
+ if self.maybe_unused_trait_imports.contains(&id) {
+ // Check later.
+ return;
+ }
+ self.session.add_lint(lint::builtin::UNUSED_IMPORTS,
+ id,
+ span,
+ "unused import".to_string());
+ } else {
+ // This trait import is definitely used, in a way other than
+ // method resolution.
+ self.maybe_unused_trait_imports.remove(&id);
+ }
+ }
}
impl<'a, 'b, 'v, 'tcx> Visitor<'v> for UnusedImportCheckVisitor<'a, 'b, 'tcx> {
@@ -144,14 +158,7 @@ impl<'a, 'b, 'v, 'tcx> Visitor<'v> for UnusedImportCheckVisitor<'a, 'b, 'tcx> {
}
}
ViewPathGlob(_) => {
- if !self.used_imports.contains(&(item.id, TypeNS)) &&
- !self.used_imports.contains(&(item.id, ValueNS)) {
- self.session
- .add_lint(lint::builtin::UNUSED_IMPORTS,
- item.id,
- p.span,
- "unused import".to_string());
- }
+ self.check_import(item.id, p.span);
}
}
}
diff --git a/src/librustc_resolve/lib.rs b/src/librustc_resolve/lib.rs
index c32acb7bb269f..15ca1d51ab504 100644
--- a/src/librustc_resolve/lib.rs
+++ b/src/librustc_resolve/lib.rs
@@ -60,13 +60,12 @@ use rustc::middle::def_id::DefId;
use rustc::middle::pat_util::pat_bindings;
use rustc::middle::privacy::*;
use rustc::middle::subst::{ParamSpace, FnSpace, TypeSpace};
-use rustc::middle::ty::{Freevar, FreevarMap, TraitMap, GlobMap};
-use rustc::util::nodemap::{NodeMap, DefIdSet, FnvHashMap};
+use rustc::middle::ty::{Freevar, FreevarMap, TraitCandidate, TraitMap, GlobMap};
+use rustc::util::nodemap::{NodeMap, NodeSet, DefIdSet, FnvHashMap};
use syntax::ast;
use syntax::ast::{CRATE_NODE_ID, Ident, Name, NodeId, CrateNum, TyIs, TyI8, TyI16, TyI32, TyI64};
use syntax::ast::{TyUs, TyU8, TyU16, TyU32, TyU64, TyF64, TyF32};
-use syntax::attr::AttrMetaMethods;
use syntax::parse::token::{self, special_names, special_idents};
use syntax::codemap::{self, Span, Pos};
use syntax::util::lev_distance::{lev_distance, max_suggestion_distance};
@@ -1142,6 +1141,7 @@ pub struct Resolver<'a, 'tcx: 'a> {
used_imports: HashSet<(NodeId, Namespace)>,
used_crates: HashSet<CrateNum>,
+ maybe_unused_trait_imports: NodeSet,
// Callback function for intercepting walks
callback: Option<Box<Fn(hir_map::Node, &mut bool) -> bool>>,
@@ -1193,14 +1193,16 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
freevars_seen: NodeMap(),
export_map: NodeMap(),
trait_map: NodeMap(),
- used_imports: HashSet::new(),
- used_crates: HashSet::new(),
external_exports: DefIdSet(),
emit_errors: true,
make_glob_map: make_glob_map == MakeGlobMap::Yes,
glob_map: HashMap::new(),
+ used_imports: HashSet::new(),
+ used_crates: HashSet::new(),
+ maybe_unused_trait_imports: NodeSet(),
+
callback: None,
resolved: false,
}
@@ -3609,14 +3611,20 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
}
}
- fn get_traits_containing_item(&mut self, name: Name) -> Vec<DefId> {
+ fn get_traits_containing_item(&mut self, name: Name) -> Vec<TraitCandidate> {
debug!("(getting traits containing item) looking for '{}'", name);
- fn add_trait_info(found_traits: &mut Vec<DefId>, trait_def_id: DefId, name: Name) {
+ fn add_trait_info(found_traits: &mut Vec<TraitCandidate>,
+ trait_def_id: DefId,
+ import_id: Option<NodeId>,
+ name: Name) {
debug!("(adding trait info) found trait {:?} for method '{}'",
trait_def_id,
name);
- found_traits.push(trait_def_id);
+ found_traits.push(TraitCandidate {
+ def_id: trait_def_id,
+ import_id: import_id,
+ });
}
let mut found_traits = Vec::new();
@@ -3626,7 +3634,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
match self.current_trait_ref {
Some((trait_def_id, _)) => {
if self.trait_item_map.contains_key(&(name, trait_def_id)) {
- add_trait_info(&mut found_traits, trait_def_id, name);
+ add_trait_info(&mut found_traits, trait_def_id, None, name);
}
}
None => {} // Nothing to do.
@@ -3646,7 +3654,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
_ => continue,
};
if self.trait_item_map.contains_key(&(name, trait_def_id)) {
- add_trait_info(&mut found_traits, trait_def_id, name);
+ add_trait_info(&mut found_traits, trait_def_id, None, name);
}
}
}
@@ -3662,9 +3670,9 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
Some(..) | None => continue,
};
if self.trait_item_map.contains_key(&(name, did)) {
- add_trait_info(&mut found_traits, did, name);
let id = import.type_ns.id;
- self.used_imports.insert((id, TypeNS));
+ add_trait_info(&mut found_traits, did, Some(id), name);
+ self.maybe_unused_trait_imports.insert(id);
let trait_name = self.get_trait_name(did);
self.record_import_use(id, trait_name);
if let Some(DefId{krate: kid, ..}) = target.target_module.def_id() {
@@ -3815,6 +3823,7 @@ fn module_to_string(module: &Module) -> String {
pub struct CrateMap {
pub def_map: RefCell<DefMap>,
pub freevars: FreevarMap,
+ pub maybe_unused_trait_imports: NodeSet,
pub export_map: ExportMap,
pub trait_map: TraitMap,
pub external_exports: ExternalExports,
@@ -3843,6 +3852,7 @@ pub fn resolve_crate<'a, 'tcx>(session: &'a Session,
CrateMap {
def_map: resolver.def_map,
freevars: resolver.freevars,
+ maybe_unused_trait_imports: resolver.maybe_unused_trait_imports,
export_map: resolver.export_map,
trait_map: resolver.trait_map,
external_exports: resolver.external_exports,
diff --git a/src/librustc_resolve/resolve_imports.rs b/src/librustc_resolve/resolve_imports.rs
index fd471893acd53..4f9a70626665b 100644
--- a/src/librustc_resolve/resolve_imports.rs
+++ b/src/librustc_resolve/resolve_imports.rs
@@ -30,7 +30,6 @@ use rustc::middle::def_id::DefId;
use rustc::middle::privacy::*;
use syntax::ast::{NodeId, Name};
-use syntax::attr::AttrMetaMethods;
use syntax::codemap::Span;
use std::mem::replace;
diff --git a/src/librustc_trans/trans/common.rs b/src/librustc_trans/trans/common.rs
index fa500ab93552c..69b21a161766b 100644
--- a/src/librustc_trans/trans/common.rs
+++ b/src/librustc_trans/trans/common.rs
@@ -38,7 +38,7 @@ use trans::type_::Type;
use trans::type_of;
use middle::traits;
use middle::ty::{self, HasTypeFlags, Ty};
-use middle::ty::fold::{TypeFolder, TypeFoldable};
+use middle::ty::fold::TypeFoldable;
use rustc_front::hir;
use rustc::mir::repr::Mir;
use util::nodemap::{FnvHashMap, NodeMap};
diff --git a/src/librustc_trans/trans/monomorphize.rs b/src/librustc_trans/trans/monomorphize.rs
index 9c1fcaff7c895..214a6aa612420 100644
--- a/src/librustc_trans/trans/monomorphize.rs
+++ b/src/librustc_trans/trans/monomorphize.rs
@@ -16,7 +16,7 @@ use middle::def_id::DefId;
use middle::infer::normalize_associated_type;
use middle::subst;
use middle::subst::{Subst, Substs};
-use middle::ty::fold::{TypeFolder, TypeFoldable};
+use middle::ty::fold::TypeFoldable;
use trans::attributes;
use trans::base::{trans_enum_variant, push_ctxt, get_item_val};
use trans::base::trans_fn;
diff --git a/src/librustc_typeck/check/intrinsic.rs b/src/librustc_typeck/check/intrinsic.rs
index b9fec44ec4030..18f1ad3d4d3dd 100644
--- a/src/librustc_typeck/check/intrinsic.rs
+++ b/src/librustc_typeck/check/intrinsic.rs
@@ -11,18 +11,15 @@
//! Type-checking for the rust-intrinsic and platform-intrinsic
//! intrinsics that the compiler exposes.
-use astconv::AstConv;
use intrinsics;
use middle::subst;
use middle::ty::FnSig;
use middle::ty::{self, Ty};
-use middle::ty::fold::TypeFolder;
use {CrateCtxt, require_same_types};
use std::collections::{HashMap};
use syntax::abi;
use syntax::ast;
-use syntax::attr::AttrMetaMethods;
use syntax::codemap::Span;
use syntax::parse::token;
diff --git a/src/librustc_typeck/check/method/mod.rs b/src/librustc_typeck/check/method/mod.rs
index e0ad51b4ea1b5..e74b013152f28 100644
--- a/src/librustc_typeck/check/method/mod.rs
+++ b/src/librustc_typeck/check/method/mod.rs
@@ -10,7 +10,6 @@
//! Method lookup: the secret sauce of Rust. See `README.md`.
-use astconv::AstConv;
use check::FnCtxt;
use middle::def;
use middle::def_id::DefId;
@@ -126,6 +125,11 @@ pub fn lookup<'a, 'tcx>(fcx: &FnCtxt<'a, 'tcx>,
let mode = probe::Mode::MethodCall;
let self_ty = fcx.infcx().resolve_type_vars_if_possible(&self_ty);
let pick = try!(probe::probe(fcx, span, mode, method_name, self_ty, call_expr.id));
+
+ if let Some(import_id) = pick.import_id {
+ fcx.tcx().used_trait_imports.borrow_mut().insert(import_id);
+ }
+
Ok(confirm::confirm(fcx, span, self_expr, call_expr, self_ty, pick, supplied_method_types))
}
@@ -338,6 +342,11 @@ pub fn resolve_ufcs<'a, 'tcx>(fcx: &FnCtxt<'a, 'tcx>,
{
let mode = probe::Mode::Path;
let pick = try!(probe::probe(fcx, span, mode, method_name, self_ty, expr_id));
+
+ if let Some(import_id) = pick.import_id {
+ fcx.tcx().used_trait_imports.borrow_mut().insert(import_id);
+ }
+
let def_id = pick.item.def_id();
let mut lp = LastMod(AllPublic);
if let probe::InherentImplPick = pick.kind {
diff --git a/src/librustc_typeck/check/method/probe.rs b/src/librustc_typeck/check/method/probe.rs
index ed819d46041e6..1ee7c0bf97c53 100644
--- a/src/librustc_typeck/check/method/probe.rs
+++ b/src/librustc_typeck/check/method/probe.rs
@@ -44,6 +44,7 @@ struct ProbeContext<'a, 'tcx:'a> {
inherent_candidates: Vec<Candidate<'tcx>>,
extension_candidates: Vec<Candidate<'tcx>>,
impl_dups: HashSet<DefId>,
+ import_id: Option<ast::NodeId>,
/// Collects near misses when the candidate functions are missing a `self` keyword and is only
/// used for error reporting
@@ -66,6 +67,7 @@ struct Candidate<'tcx> {
xform_self_ty: Ty<'tcx>,
item: ty::ImplOrTraitItem<'tcx>,
kind: CandidateKind<'tcx>,
+ import_id: Option<ast::NodeId>,
}
#[derive(Debug)]
@@ -83,6 +85,7 @@ enum CandidateKind<'tcx> {
pub struct Pick<'tcx> {
pub item: ty::ImplOrTraitItem<'tcx>,
pub kind: PickKind<'tcx>,
+ pub import_id: Option<ast::NodeId>,
// Indicates that the source expression should be autoderef'd N times
//
@@ -246,6 +249,7 @@ impl<'a,'tcx> ProbeContext<'a,'tcx> {
inherent_candidates: Vec::new(),
extension_candidates: Vec::new(),
impl_dups: HashSet::new(),
+ import_id: None,
steps: Rc::new(steps),
opt_simplified_steps: opt_simplified_steps,
static_candidates: Vec::new(),
@@ -427,7 +431,8 @@ impl<'a,'tcx> ProbeContext<'a,'tcx> {
self.inherent_candidates.push(Candidate {
xform_self_ty: xform_self_ty,
item: item,
- kind: InherentImplCandidate(impl_substs, obligations)
+ kind: InherentImplCandidate(impl_substs, obligations),
+ import_id: self.import_id,
});
}
@@ -455,7 +460,8 @@ impl<'a,'tcx> ProbeContext<'a,'tcx> {
this.inherent_candidates.push(Candidate {
xform_self_ty: xform_self_ty,
item: item,
- kind: ObjectCandidate
+ kind: ObjectCandidate,
+ import_id: this.import_id,
});
});
}
@@ -524,7 +530,8 @@ impl<'a,'tcx> ProbeContext<'a,'tcx> {
this.inherent_candidates.push(Candidate {
xform_self_ty: xform_self_ty,
item: item,
- kind: WhereClauseCandidate(poly_trait_ref)
+ kind: WhereClauseCandidate(poly_trait_ref),
+ import_id: this.import_id,
});
});
}
@@ -568,9 +575,13 @@ impl<'a,'tcx> ProbeContext<'a,'tcx> {
let mut duplicates = HashSet::new();
let opt_applicable_traits = self.fcx.ccx.trait_map.get(&expr_id);
if let Some(applicable_traits) = opt_applicable_traits {
- for &trait_did in applicable_traits {
+ for trait_candidate in applicable_traits {
+ let trait_did = trait_candidate.def_id;
if duplicates.insert(trait_did) {
- try!(self.assemble_extension_candidates_for_trait(trait_did));
+ self.import_id = trait_candidate.import_id;
+ let result = self.assemble_extension_candidates_for_trait(trait_did);
+ self.import_id = None;
+ try!(result);
}
}
}
@@ -670,7 +681,8 @@ impl<'a,'tcx> ProbeContext<'a,'tcx> {
self.extension_candidates.push(Candidate {
xform_self_ty: xform_self_ty,
item: item.clone(),
- kind: ExtensionImplCandidate(impl_def_id, impl_substs, obligations)
+ kind: ExtensionImplCandidate(impl_def_id, impl_substs, obligations),
+ import_id: self.import_id,
});
});
}
@@ -745,7 +757,8 @@ impl<'a,'tcx> ProbeContext<'a,'tcx> {
self.inherent_candidates.push(Candidate {
xform_self_ty: xform_self_ty,
item: item.clone(),
- kind: TraitCandidate
+ kind: TraitCandidate,
+ import_id: self.import_id,
});
}
@@ -802,7 +815,8 @@ impl<'a,'tcx> ProbeContext<'a,'tcx> {
self.extension_candidates.push(Candidate {
xform_self_ty: xform_self_ty,
item: item.clone(),
- kind: TraitCandidate
+ kind: TraitCandidate,
+ import_id: self.import_id,
});
}
}
@@ -833,7 +847,8 @@ impl<'a,'tcx> ProbeContext<'a,'tcx> {
self.extension_candidates.push(Candidate {
xform_self_ty: xform_self_ty,
item: item.clone(),
- kind: WhereClauseCandidate(poly_bound)
+ kind: WhereClauseCandidate(poly_bound),
+ import_id: self.import_id,
});
}
}
@@ -1126,6 +1141,7 @@ impl<'a,'tcx> ProbeContext<'a,'tcx> {
Some(Pick {
item: probes[0].item.clone(),
kind: TraitPick,
+ import_id: probes[0].import_id,
autoderefs: 0,
autoref: None,
unsize: None
@@ -1329,6 +1345,7 @@ impl<'tcx> Candidate<'tcx> {
WhereClausePick(trait_ref.clone())
}
},
+ import_id: self.import_id,
autoderefs: 0,
autoref: None,
unsize: None
diff --git a/src/librustc_typeck/check/method/suggest.rs b/src/librustc_typeck/check/method/suggest.rs
index 955bc92a8f31e..039257d72b2ff 100644
--- a/src/librustc_typeck/check/method/suggest.rs
+++ b/src/librustc_typeck/check/method/suggest.rs
@@ -13,7 +13,6 @@
use CrateCtxt;
-use astconv::AstConv;
use check::{self, FnCtxt};
use front::map as hir_map;
use middle::ty::{self, Ty, ToPolyTraitRef, ToPredicate, HasTypeFlags};
diff --git a/src/librustc_typeck/check/mod.rs b/src/librustc_typeck/check/mod.rs
index a50213202b82c..91549ccd1310d 100644
--- a/src/librustc_typeck/check/mod.rs
+++ b/src/librustc_typeck/check/mod.rs
@@ -100,7 +100,7 @@ use middle::ty::{self, HasTypeFlags, RegionEscape, ToPolyTraitRef, Ty};
use middle::ty::{MethodCall, MethodCallee};
use middle::ty::adjustment;
use middle::ty::error::TypeError;
-use middle::ty::fold::{TypeFolder, TypeFoldable};
+use middle::ty::fold::TypeFoldable;
use middle::ty::util::Representability;
use require_c_abi_if_variadic;
use rscope::{ElisionFailureInfo, RegionScope};
diff --git a/src/librustc_typeck/check/regionck.rs b/src/librustc_typeck/check/regionck.rs
index f980945dbf220..d2fe174f3915e 100644
--- a/src/librustc_typeck/check/regionck.rs
+++ b/src/librustc_typeck/check/regionck.rs
@@ -82,7 +82,6 @@
//! relation, except that a borrowed pointer never owns its
//! contents.
-use astconv::AstConv;
use check::dropck;
use check::FnCtxt;
use middle::free_region::FreeRegionMap;
diff --git a/src/librustc_typeck/check/wf.rs b/src/librustc_typeck/check/wf.rs
index 3daf5003b97e0..8606f9f81c929 100644
--- a/src/librustc_typeck/check/wf.rs
+++ b/src/librustc_typeck/check/wf.rs
@@ -8,7 +8,6 @@
// option. This file may not be copied, modified, or distributed
// except according to those terms.
-use astconv::AstConv;
use check::{FnCtxt, Inherited, blank_fn_ctxt, regionck, wfcheck};
use constrained_type_params::{identify_constrained_type_params, Parameter};
use CrateCtxt;
diff --git a/src/librustc_typeck/check/wfcheck.rs b/src/librustc_typeck/check/wfcheck.rs
index a9bd0e3926811..dfc4ddee48758 100644
--- a/src/librustc_typeck/check/wfcheck.rs
+++ b/src/librustc_typeck/check/wfcheck.rs
@@ -8,7 +8,6 @@
// option. This file may not be copied, modified, or distributed
// except according to those terms.
-use astconv::AstConv;
use check::{FnCtxt, Inherited, blank_fn_ctxt, regionck};
use constrained_type_params::{identify_constrained_type_params, Parameter};
use CrateCtxt;
@@ -16,7 +15,6 @@ use middle::def_id::DefId;
use middle::subst::{self, TypeSpace, FnSpace, ParamSpace, SelfSpace};
use middle::traits;
use middle::ty::{self, Ty};
-use middle::ty::fold::{TypeFolder};
use std::cell::RefCell;
use std::collections::HashSet;
diff --git a/src/librustc_typeck/check/writeback.rs b/src/librustc_typeck/check/writeback.rs
index 984f227cebe79..c1d4d49512c68 100644
--- a/src/librustc_typeck/check/writeback.rs
+++ b/src/librustc_typeck/check/writeback.rs
@@ -13,7 +13,6 @@
// substitutions.
use self::ResolveReason::*;
-use astconv::AstConv;
use check::FnCtxt;
use middle::def_id::DefId;
use middle::pat_util;
diff --git a/src/librustc_typeck/check_unused.rs b/src/librustc_typeck/check_unused.rs
new file mode 100644
index 0000000000000..7a66bb05090c2
--- /dev/null
+++ b/src/librustc_typeck/check_unused.rs
@@ -0,0 +1,62 @@
+// Copyright 2015 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+use lint;
+use middle::ty;
+
+use syntax::ast;
+use syntax::codemap::{Span, DUMMY_SP};
+
+use rustc_front::hir;
+use rustc_front::intravisit::Visitor;
+
+struct UnusedTraitImportVisitor<'a, 'tcx: 'a> {
+ tcx: &'a ty::ctxt<'tcx>,
+}
+
+impl<'a, 'tcx> UnusedTraitImportVisitor<'a, 'tcx> {
+ fn check_import(&self, id: ast::NodeId, span: Span) {
+ if !self.tcx.maybe_unused_trait_imports.contains(&id) {
+ return;
+ }
+ if self.tcx.used_trait_imports.borrow().contains(&id) {
+ return;
+ }
+ self.tcx.sess.add_lint(lint::builtin::UNUSED_IMPORTS,
+ id,
+ span,
+ "unused import".to_string());
+ }
+}
+
+impl<'a, 'tcx, 'v> Visitor<'v> for UnusedTraitImportVisitor<'a, 'tcx> {
+ fn visit_item(&mut self, item: &hir::Item) {
+ if item.vis == hir::Public || item.span == DUMMY_SP {
+ return;
+ }
+ if let hir::ItemUse(ref path) = item.node {
+ match path.node {
+ hir::ViewPathSimple(..) | hir::ViewPathGlob(..) => {
+ self.check_import(item.id, path.span);
+ }
+ hir::ViewPathList(_, ref path_list) => {
+ for path_item in path_list {
+ self.check_import(path_item.node.id(), path_item.span);
+ }
+ }
+ }
+ }
+ }
+}
+
+pub fn check_crate(tcx: &ty::ctxt) {
+ let mut visitor = UnusedTraitImportVisitor { tcx: tcx };
+ tcx.map.krate().visit_all_items(&mut visitor);
+}
diff --git a/src/librustc_typeck/collect.rs b/src/librustc_typeck/collect.rs
index 86a56e718b5cf..860cbf7da1f0d 100644
--- a/src/librustc_typeck/collect.rs
+++ b/src/librustc_typeck/collect.rs
@@ -78,7 +78,7 @@ use middle::subst::{Substs, FnSpace, ParamSpace, SelfSpace, TypeSpace, VecPerPar
use middle::ty::{ToPredicate, ImplContainer, ImplOrTraitItemContainer, TraitContainer};
use middle::ty::{self, RegionEscape, ToPolyTraitRef, Ty, TypeScheme};
use middle::ty::{VariantKind};
-use middle::ty::fold::{TypeFolder, TypeFoldable};
+use middle::ty::fold::TypeFoldable;
use middle::ty::util::IntTypeExt;
use middle::infer;
use rscope::*;
diff --git a/src/librustc_typeck/lib.rs b/src/librustc_typeck/lib.rs
index 495b8995ceea2..39e650b308264 100644
--- a/src/librustc_typeck/lib.rs
+++ b/src/librustc_typeck/lib.rs
@@ -120,6 +120,7 @@ use std::cell::RefCell;
pub mod diagnostics;
pub mod check;
+pub mod check_unused;
mod rscope;
mod astconv;
pub mod collect;
@@ -361,6 +362,7 @@ pub fn check_crate(tcx: &ty::ctxt, trait_map: ty::TraitMap) {
time(time_passes, "wf checking (new)", ||
check::check_wf_new(&ccx));
+ check_unused::check_crate(tcx);
check_for_entry_fn(&ccx);
tcx.sess.abort_if_errors();
}
diff --git a/src/librustdoc/clean/inline.rs b/src/librustdoc/clean/inline.rs
index 40e7146670907..ff00643923a74 100644
--- a/src/librustdoc/clean/inline.rs
+++ b/src/librustdoc/clean/inline.rs
@@ -13,7 +13,6 @@
use std::collections::HashSet;
use syntax::ast;
-use syntax::attr::AttrMetaMethods;
use rustc_front::hir;
use rustc::middle::cstore::{self, CrateStore};
diff --git a/src/libstd/sys/unix/fs.rs b/src/libstd/sys/unix/fs.rs
index 8ea8f0c6c771b..07e49e2da97b0 100644
--- a/src/libstd/sys/unix/fs.rs
+++ b/src/libstd/sys/unix/fs.rs
@@ -8,7 +8,6 @@
// option. This file may not be copied, modified, or distributed
// except according to those terms.
-use io::prelude::*;
use os::unix::prelude::*;
use ffi::{CString, CStr, OsString, OsStr};
diff --git a/src/libsyntax/diagnostic.rs b/src/libsyntax/diagnostic.rs
index b854a2f2a0a17..3b7b5d854adac 100644
--- a/src/libsyntax/diagnostic.rs
+++ b/src/libsyntax/diagnostic.rs
@@ -289,8 +289,6 @@ pub enum Level {
impl fmt::Display for Level {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
- use std::fmt::Display;
-
match *self {
Bug => "error: internal compiler error".fmt(f),
Fatal | Error => "error".fmt(f),
diff --git a/src/libsyntax/parse/mod.rs b/src/libsyntax/parse/mod.rs
index e9c8173a4d980..1b6f963f5751c 100644
--- a/src/libsyntax/parse/mod.rs
+++ b/src/libsyntax/parse/mod.rs
@@ -19,7 +19,6 @@ use ptr::P;
use str::char_at;
use std::cell::RefCell;
-use std::io::Read;
use std::iter;
use std::path::{Path, PathBuf};
use std::rc::Rc;
diff --git a/src/libsyntax/parse/parser.rs b/src/libsyntax/parse/parser.rs
index 7502a8cbc3546..566794a13612f 100644
--- a/src/libsyntax/parse/parser.rs
+++ b/src/libsyntax/parse/parser.rs
@@ -78,7 +78,6 @@ use parse::PResult;
use diagnostic::FatalError;
use std::collections::HashSet;
-use std::io::prelude::*;
use std::mem;
use std::path::{Path, PathBuf};
use std::rc::Rc;
diff --git a/src/libsyntax/util/interner.rs b/src/libsyntax/util/interner.rs
index 6e9c161293de2..8e20358027b22 100644
--- a/src/libsyntax/util/interner.rs
+++ b/src/libsyntax/util/interner.rs
@@ -115,14 +115,12 @@ impl Ord for RcStr {
impl fmt::Debug for RcStr {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
- use std::fmt::Debug;
self[..].fmt(f)
}
}
impl fmt::Display for RcStr {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
- use std::fmt::Display;
self[..].fmt(f)
}
}
diff --git a/src/libtest/lib.rs b/src/libtest/lib.rs
index 7ffe567ac83c1..c41ac49b03474 100644
--- a/src/libtest/lib.rs
+++ b/src/libtest/lib.rs
@@ -58,9 +58,7 @@ use self::TestEvent::*;
use self::NamePadding::*;
use self::OutputLocation::*;
-use stats::Stats;
use getopts::{OptGroup, optflag, optopt};
-use serialize::Encodable;
use std::boxed::FnBox;
use term::Terminal;
use term::color::{Color, RED, YELLOW, GREEN, CYAN};
diff --git a/src/rustbook/main.rs b/src/rustbook/main.rs
index d23e868eeadd1..2e03ad512b5a8 100644
--- a/src/rustbook/main.rs
+++ b/src/rustbook/main.rs
@@ -19,10 +19,8 @@ extern crate rustdoc;
extern crate rustc_back;
use std::env;
-use std::error::Error;
use std::process;
use std::sync::atomic::{AtomicIsize, ATOMIC_ISIZE_INIT, Ordering};
-use subcommand::Subcommand;
use term::Term;
mod term;
diff --git a/src/test/compile-fail/lint-unused-imports.rs b/src/test/compile-fail/lint-unused-imports.rs
index 1468ae64d9418..3eb0d48956b16 100644
--- a/src/test/compile-fail/lint-unused-imports.rs
+++ b/src/test/compile-fail/lint-unused-imports.rs
@@ -24,6 +24,8 @@ use test::A; //~ ERROR unused import
// Be sure that if we just bring some methods into scope that they're also
// counted as being used.
use test::B;
+// But only when actually used: do not get confused by the method with the same name.
+use test::B2; //~ ERROR unused import
// Make sure this import is warned about when at least one of its imported names
// is unused
@@ -37,6 +39,7 @@ mod test2 {
mod test {
pub trait A { fn a(&self) {} }
pub trait B { fn b(&self) {} }
+ pub trait B2 { fn b(&self) {} }
pub struct C;
impl A for C {}
impl B for C {}