From ff832405d07d6c34ee060e26acf0aa6143b79d3f Mon Sep 17 00:00:00 2001 From: Cldfire Date: Tue, 31 Oct 2017 13:31:48 -0400 Subject: [PATCH 1/2] Suggest renaming import if names clash --- src/librustc_resolve/lib.rs | 26 +++++++++++++++++++++++--- 1 file changed, 23 insertions(+), 3 deletions(-) diff --git a/src/librustc_resolve/lib.rs b/src/librustc_resolve/lib.rs index 83eeaf551c56c..3b27890013a22 100644 --- a/src/librustc_resolve/lib.rs +++ b/src/librustc_resolve/lib.rs @@ -3606,12 +3606,12 @@ impl<'a> Resolver<'a> { } } - fn report_conflict(&mut self, + fn report_conflict<'b>(&mut self, parent: Module, ident: Ident, ns: Namespace, - new_binding: &NameBinding, - old_binding: &NameBinding) { + new_binding: &NameBinding<'b>, + old_binding: &NameBinding<'b>) { // Error on the second of two conflicting names if old_binding.span.lo() > new_binding.span.lo() { return self.report_conflict(parent, ident, ns, old_binding, new_binding); @@ -3683,6 +3683,26 @@ impl<'a> Resolver<'a> { old_noun, old_kind, name)); } + // See https://github.com/rust-lang/rust/issues/32354 + if old_binding.is_import() || new_binding.is_import() { + let binding = if new_binding.is_import() { + new_binding + } else { + old_binding + }; + + let cm = self.session.codemap(); + let rename_msg = "You can use `as` to change the binding name of the import"; + + if let Ok(snippet) = cm.span_to_snippet(binding.span) { + err.span_suggestion(binding.span, + rename_msg, + format!("{} as Other{}", snippet, name)); + } else { + err.span_label(binding.span, rename_msg); + } + } + err.emit(); self.name_already_seen.insert(name, span); } From 61396a8286cde05bea720f5738eb939cc32b8d34 Mon Sep 17 00:00:00 2001 From: Cldfire Date: Tue, 31 Oct 2017 19:35:51 -0400 Subject: [PATCH 2/2] Add UI test --- .../issue-32354-suggest-import-rename.rs | 22 +++++++++++++++++++ .../issue-32354-suggest-import-rename.stderr | 16 ++++++++++++++ 2 files changed, 38 insertions(+) create mode 100644 src/test/ui/suggestions/issue-32354-suggest-import-rename.rs create mode 100644 src/test/ui/suggestions/issue-32354-suggest-import-rename.stderr diff --git a/src/test/ui/suggestions/issue-32354-suggest-import-rename.rs b/src/test/ui/suggestions/issue-32354-suggest-import-rename.rs new file mode 100644 index 0000000000000..51aba27498f88 --- /dev/null +++ b/src/test/ui/suggestions/issue-32354-suggest-import-rename.rs @@ -0,0 +1,22 @@ +// Copyright 2017 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 or the MIT license +// , at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +pub mod extension1 { + pub trait ConstructorExtension {} +} + +pub mod extension2 { + pub trait ConstructorExtension {} +} + +use extension1::ConstructorExtension; +use extension2::ConstructorExtension; + +fn main() {} diff --git a/src/test/ui/suggestions/issue-32354-suggest-import-rename.stderr b/src/test/ui/suggestions/issue-32354-suggest-import-rename.stderr new file mode 100644 index 0000000000000..0798519128474 --- /dev/null +++ b/src/test/ui/suggestions/issue-32354-suggest-import-rename.stderr @@ -0,0 +1,16 @@ +error[E0252]: the name `ConstructorExtension` is defined multiple times + --> $DIR/issue-32354-suggest-import-rename.rs:20:5 + | +19 | use extension1::ConstructorExtension; + | -------------------------------- previous import of the trait `ConstructorExtension` here +20 | use extension2::ConstructorExtension; + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `ConstructorExtension` reimported here + | + = note: `ConstructorExtension` must be defined only once in the type namespace of this module +help: You can use `as` to change the binding name of the import + | +20 | use extension2::ConstructorExtension as OtherConstructorExtension; + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +error: aborting due to previous error +