1 // Copyright 2017 The Rust Project Developers. See the COPYRIGHT
2 // file at the top-level directory of this distribution and at
3 // http://rust-lang.org/COPYRIGHT.
5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8 // option. This file may not be copied, modified, or distributed
9 // except according to those terms.
11 use rustc::hir::def_id::{CrateNum, DefId, LOCAL_CRATE};
13 use rustc::hir::itemlikevisit::ItemLikeVisitor;
14 use rustc::traits::{self, Reveal};
15 use rustc::ty::{self, TyCtxt};
17 pub fn crate_inherent_impls_overlap_check<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
18 crate_num: CrateNum) {
19 assert_eq!(crate_num, LOCAL_CRATE);
20 let krate = tcx.hir.krate();
21 krate.visit_all_item_likes(&mut InherentOverlapChecker { tcx });
24 struct InherentOverlapChecker<'a, 'tcx: 'a> {
25 tcx: TyCtxt<'a, 'tcx, 'tcx>
28 impl<'a, 'tcx> InherentOverlapChecker<'a, 'tcx> {
29 fn check_for_common_items_in_impls(&self, impl1: DefId, impl2: DefId) {
30 #[derive(Copy, Clone, PartialEq)]
36 let name_and_namespace = |def_id| {
37 let item = self.tcx.associated_item(def_id);
38 (item.name, match item.kind {
39 ty::AssociatedKind::Type => Namespace::Type,
40 ty::AssociatedKind::Const |
41 ty::AssociatedKind::Method => Namespace::Value,
45 let impl_items1 = self.tcx.associated_item_def_ids(impl1);
46 let impl_items2 = self.tcx.associated_item_def_ids(impl2);
48 for &item1 in &impl_items1[..] {
49 let (name, namespace) = name_and_namespace(item1);
51 for &item2 in &impl_items2[..] {
52 if (name, namespace) == name_and_namespace(item2) {
53 struct_span_err!(self.tcx.sess,
54 self.tcx.span_of_impl(item1).unwrap(),
56 "duplicate definitions with name `{}`",
58 .span_label(self.tcx.span_of_impl(item1).unwrap(),
59 &format!("duplicate definitions for `{}`", name))
60 .span_label(self.tcx.span_of_impl(item2).unwrap(),
61 &format!("other definition for `{}`", name))
68 fn check_for_overlapping_inherent_impls(&self, ty_def_id: DefId) {
69 let impls = self.tcx.inherent_impls(ty_def_id);
71 for (i, &impl1_def_id) in impls.iter().enumerate() {
72 for &impl2_def_id in &impls[(i + 1)..] {
73 self.tcx.infer_ctxt((), Reveal::UserFacing).enter(|infcx| {
74 if traits::overlapping_impls(&infcx, impl1_def_id, impl2_def_id).is_some() {
75 self.check_for_common_items_in_impls(impl1_def_id, impl2_def_id)
83 impl<'a, 'tcx, 'v> ItemLikeVisitor<'v> for InherentOverlapChecker<'a, 'tcx> {
84 fn visit_item(&mut self, item: &'v hir::Item) {
89 hir::ItemUnion(..) => {
90 let type_def_id = self.tcx.hir.local_def_id(item.id);
91 self.check_for_overlapping_inherent_impls(type_def_id);
97 fn visit_trait_item(&mut self, _trait_item: &hir::TraitItem) {
100 fn visit_impl_item(&mut self, _impl_item: &hir::ImplItem) {