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 namespace::Namespace;
12 use rustc::hir::def_id::{CrateNum, DefId, LOCAL_CRATE};
14 use rustc::hir::itemlikevisit::ItemLikeVisitor;
15 use rustc::traits::{self, IntercrateMode};
16 use rustc::ty::TyCtxt;
20 pub fn crate_inherent_impls_overlap_check<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
21 crate_num: CrateNum) {
22 assert_eq!(crate_num, LOCAL_CRATE);
23 let krate = tcx.hir.krate();
24 krate.visit_all_item_likes(&mut InherentOverlapChecker { tcx });
27 struct InherentOverlapChecker<'a, 'tcx: 'a> {
28 tcx: TyCtxt<'a, 'tcx, 'tcx>
31 impl<'a, 'tcx> InherentOverlapChecker<'a, 'tcx> {
32 fn check_for_common_items_in_impls(&self, impl1: DefId, impl2: DefId,
33 overlap: traits::OverlapResult,
34 used_to_be_allowed: bool) {
36 let name_and_namespace = |def_id| {
37 let item = self.tcx.associated_item(def_id);
38 (item.name, Namespace::from(item.kind))
41 let impl_items1 = self.tcx.associated_item_def_ids(impl1);
42 let impl_items2 = self.tcx.associated_item_def_ids(impl2);
44 for &item1 in &impl_items1[..] {
45 let (name, namespace) = name_and_namespace(item1);
47 for &item2 in &impl_items2[..] {
48 if (name, namespace) == name_and_namespace(item2) {
49 let node_id = self.tcx.hir.as_local_node_id(impl1);
50 let mut err = if used_to_be_allowed && node_id.is_some() {
51 self.tcx.struct_span_lint_node(
52 lint::builtin::INCOHERENT_FUNDAMENTAL_IMPLS,
54 self.tcx.span_of_impl(item1).unwrap(),
55 &format!("duplicate definitions with name `{}` (E0592)", name)
58 struct_span_err!(self.tcx.sess,
59 self.tcx.span_of_impl(item1).unwrap(),
61 "duplicate definitions with name `{}`",
65 err.span_label(self.tcx.span_of_impl(item1).unwrap(),
66 format!("duplicate definitions for `{}`", name));
67 err.span_label(self.tcx.span_of_impl(item2).unwrap(),
68 format!("other definition for `{}`", name));
70 for cause in &overlap.intercrate_ambiguity_causes {
71 cause.add_intercrate_ambiguity_hint(&mut err);
80 fn check_for_overlapping_inherent_impls(&self, ty_def_id: DefId) {
81 let impls = self.tcx.inherent_impls(ty_def_id);
83 for (i, &impl1_def_id) in impls.iter().enumerate() {
84 for &impl2_def_id in &impls[(i + 1)..] {
85 let used_to_be_allowed = self.tcx.infer_ctxt().enter(|infcx| {
86 if let Some(overlap) =
87 traits::overlapping_impls(&infcx, impl1_def_id, impl2_def_id,
88 IntercrateMode::Issue43355)
90 self.check_for_common_items_in_impls(
91 impl1_def_id, impl2_def_id, overlap, false);
98 if used_to_be_allowed {
99 self.tcx.infer_ctxt().enter(|infcx| {
100 if let Some(overlap) =
101 traits::overlapping_impls(&infcx, impl1_def_id, impl2_def_id,
102 IntercrateMode::Fixed)
104 self.check_for_common_items_in_impls(
105 impl1_def_id, impl2_def_id, overlap, true);
114 impl<'a, 'tcx, 'v> ItemLikeVisitor<'v> for InherentOverlapChecker<'a, 'tcx> {
115 fn visit_item(&mut self, item: &'v hir::Item) {
118 hir::ItemStruct(..) |
120 hir::ItemUnion(..) => {
121 let type_def_id = self.tcx.hir.local_def_id(item.id);
122 self.check_for_overlapping_inherent_impls(type_def_id);
128 fn visit_trait_item(&mut self, _trait_item: &hir::TraitItem) {
131 fn visit_impl_item(&mut self, _impl_item: &hir::ImplItem) {