From 51fd3bf6a823a406cccfbf48de4190cde42f6618 Mon Sep 17 00:00:00 2001 From: Alex Crichton Date: Fri, 24 Aug 2018 14:00:15 -0700 Subject: [PATCH] rustc: Suggest removing `extern crate` in 2018 This commit updates the `unused_extern_crates` lint to make automatic suggestions about removing `extern crate` annotations in the 2018 edition. This ended up being a little easier than originally though due to what's likely been fixed issues in the resolver! Closes #52829 --- src/librustc_typeck/check_unused.rs | 7 +++- .../auxiliary/remove-extern-crate.rs | 19 +++++++++ .../ui/rust-2018/remove-extern-crate.fixed | 39 +++++++++++++++++++ src/test/ui/rust-2018/remove-extern-crate.rs | 39 +++++++++++++++++++ .../ui/rust-2018/remove-extern-crate.stderr | 25 ++++++++++++ 5 files changed, 128 insertions(+), 1 deletion(-) create mode 100644 src/test/ui/rust-2018/auxiliary/remove-extern-crate.rs create mode 100644 src/test/ui/rust-2018/remove-extern-crate.fixed create mode 100644 src/test/ui/rust-2018/remove-extern-crate.rs create mode 100644 src/test/ui/rust-2018/remove-extern-crate.stderr diff --git a/src/librustc_typeck/check_unused.rs b/src/librustc_typeck/check_unused.rs index 52e6663792b..d7aec1d62cd 100644 --- a/src/librustc_typeck/check_unused.rs +++ b/src/librustc_typeck/check_unused.rs @@ -176,7 +176,12 @@ fn unused_crates_lint<'tcx>(tcx: TyCtxt<'_, 'tcx, 'tcx>) { }; let replacement = visibility_qualified(&item.vis, &base_replacement); tcx.struct_span_lint_node(lint, id, extern_crate.span, msg) - .span_suggestion_short(extern_crate.span, &help, replacement) + .span_suggestion_short_with_applicability( + extern_crate.span, + &help, + replacement, + Applicability::MachineApplicable, + ) .emit(); } } diff --git a/src/test/ui/rust-2018/auxiliary/remove-extern-crate.rs b/src/test/ui/rust-2018/auxiliary/remove-extern-crate.rs new file mode 100644 index 00000000000..9daaca1fb8f --- /dev/null +++ b/src/test/ui/rust-2018/auxiliary/remove-extern-crate.rs @@ -0,0 +1,19 @@ +// Copyright 2018 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. + +#[macro_export] +macro_rules! foo { + () => () +} + +#[macro_export] +macro_rules! bar { + () => () +} diff --git a/src/test/ui/rust-2018/remove-extern-crate.fixed b/src/test/ui/rust-2018/remove-extern-crate.fixed new file mode 100644 index 00000000000..995be4290b8 --- /dev/null +++ b/src/test/ui/rust-2018/remove-extern-crate.fixed @@ -0,0 +1,39 @@ +// Copyright 2018 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. + +// run-rustfix +// edition:2018 +// compile-pass +// aux-build:remove-extern-crate.rs + +#![warn(rust_2018_idioms)] + + +use core as another_name; +use remove_extern_crate; +#[macro_use] +extern crate remove_extern_crate as something_else; + +fn main() { + another_name::mem::drop(3); + another::foo(); + remove_extern_crate::foo!(); + bar!(); +} + +mod another { + use core; + use remove_extern_crate; + + pub fn foo() { + core::mem::drop(4); + remove_extern_crate::foo!(); + } +} diff --git a/src/test/ui/rust-2018/remove-extern-crate.rs b/src/test/ui/rust-2018/remove-extern-crate.rs new file mode 100644 index 00000000000..3ab97a74287 --- /dev/null +++ b/src/test/ui/rust-2018/remove-extern-crate.rs @@ -0,0 +1,39 @@ +// Copyright 2018 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. + +// run-rustfix +// edition:2018 +// compile-pass +// aux-build:remove-extern-crate.rs + +#![warn(rust_2018_idioms)] + +extern crate core; +extern crate core as another_name; +use remove_extern_crate; +#[macro_use] +extern crate remove_extern_crate as something_else; + +fn main() { + another_name::mem::drop(3); + another::foo(); + remove_extern_crate::foo!(); + bar!(); +} + +mod another { + extern crate core; + use remove_extern_crate; + + pub fn foo() { + core::mem::drop(4); + remove_extern_crate::foo!(); + } +} diff --git a/src/test/ui/rust-2018/remove-extern-crate.stderr b/src/test/ui/rust-2018/remove-extern-crate.stderr new file mode 100644 index 00000000000..752a7b180de --- /dev/null +++ b/src/test/ui/rust-2018/remove-extern-crate.stderr @@ -0,0 +1,25 @@ +warning: unused extern crate + --> $DIR/remove-extern-crate.rs:18:1 + | +LL | extern crate core; + | ^^^^^^^^^^^^^^^^^^ help: remove it + | +note: lint level defined here + --> $DIR/remove-extern-crate.rs:16:9 + | +LL | #![warn(rust_2018_idioms)] + | ^^^^^^^^^^^^^^^^ + = note: #[warn(unused_extern_crates)] implied by #[warn(rust_2018_idioms)] + +warning: `extern crate` is not idiomatic in the new edition + --> $DIR/remove-extern-crate.rs:19:1 + | +LL | extern crate core as another_name; + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: convert it to a `use` + +warning: `extern crate` is not idiomatic in the new edition + --> $DIR/remove-extern-crate.rs:32:5 + | +LL | extern crate core; + | ^^^^^^^^^^^^^^^^^^ help: convert it to a `use` +