rustc: Add support for extern crate foo as bar

The compiler will now issue a warning for crates that have syntax of the form
`extern crate "foo" as bar`, but it will still continue to accept this syntax.
Additionally, the string `foo-bar` will match the crate name `foo_bar` to assist
in the transition period as well.

This patch will land hopefully in tandem with a Cargo patch that will start
translating all crate names to have underscores instead of hyphens.

cc #23533

src/test/compile-fail/bad-crate-id.rs

@@ -9,5 +9,6 @@
 // except according to those terms.
 
 extern crate "" as foo; //~ ERROR: crate name must not be empty
+//~^ WARNING: obsolete syntax
 
 fn main() {}

src/test/compile-fail/bad-crate-id2.rs

@@ -9,5 +9,6 @@
 // except according to those terms.
 
 extern crate "#a" as bar; //~ ERROR: invalid character `#` in crate name: `#a`
+//~^ WARNING: obsolete syntax
 
 fn main() {}

src/test/compile-fail/coherence-all-remote.rs

@@ -8,9 +8,9 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// aux-build:coherence-lib.rs
+// aux-build:coherence_lib.rs
 
-extern crate "coherence-lib" as lib;
+extern crate coherence_lib as lib;
 use lib::Remote1;
 
 impl<T> Remote1<T> for isize { }

src/test/compile-fail/coherence-bigint-param.rs

@@ -8,9 +8,9 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// aux-build:coherence-lib.rs
+// aux-build:coherence_lib.rs
 
-extern crate "coherence-lib" as lib;
+extern crate coherence_lib as lib;
 use lib::Remote1;
 
 pub struct BigInt;

src/test/compile-fail/coherence-cow-no-cover.rs

@@ -8,11 +8,11 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// aux-build:coherence-lib.rs
+// aux-build:coherence_lib.rs
 
 // Test that it's not ok for U to appear uncovered
 
-extern crate "coherence-lib" as lib;
+extern crate coherence_lib as lib;
 use lib::{Remote,Pair};
 
 pub struct Cover<T>(T);

src/test/compile-fail/coherence-lone-type-parameter.rs

@@ -8,9 +8,9 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// aux-build:coherence-lib.rs
+// aux-build:coherence_lib.rs
 
-extern crate "coherence-lib" as lib;
+extern crate coherence_lib as lib;
 use lib::Remote;
 
 impl<T> Remote for T { }

src/test/compile-fail/coherence-orphan.rs

@@ -9,11 +9,11 @@
 // except according to those terms.
 
 // ignore-tidy-linelength
-// aux-build:coherence-orphan-lib.rs
+// aux-build:coherence_orphan_lib.rs
 
 #![feature(optin_builtin_traits)]
 
-extern crate "coherence-orphan-lib" as lib;
+extern crate coherence_orphan_lib as lib;
 
 use lib::TheTrait;
 

src/test/compile-fail/coherence-overlapping-pairs.rs

@@ -8,9 +8,9 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// aux-build:coherence-lib.rs
+// aux-build:coherence_lib.rs
 
-extern crate "coherence-lib" as lib;
+extern crate coherence_lib as lib;
 use lib::Remote;
 
 struct Foo;

src/test/compile-fail/coherence-pair-covered-uncovered-1.rs

@@ -11,9 +11,9 @@
 // Test that the same coverage rules apply even if the local type appears in the
 // list of type parameters, not the self type.
 
-// aux-build:coherence-lib.rs
+// aux-build:coherence_lib.rs
 
-extern crate "coherence-lib" as lib;
+extern crate coherence_lib as lib;
 use lib::{Remote1, Pair};
 
 pub struct Local<T>(T);

src/test/compile-fail/coherence-pair-covered-uncovered.rs

@@ -8,9 +8,9 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// aux-build:coherence-lib.rs
+// aux-build:coherence_lib.rs
 
-extern crate "coherence-lib" as lib;
+extern crate coherence_lib as lib;
 use lib::{Remote, Pair};
 
 struct Local<T>(T);

src/test/compile-fail/derive-no-std-not-supported.rs

@@ -13,7 +13,7 @@
 
 extern crate core;
 extern crate rand;
-extern crate "serialize" as rustc_serialize;
+extern crate serialize as rustc_serialize;
 
 #[derive(Rand)]  //~ ERROR this trait cannot be derived
 //~^ WARNING `#[derive(Rand)]` is deprecated

src/test/compile-fail/issue-11680.rs

@@ -8,9 +8,9 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// aux-build:issue-11680.rs
+// aux-build:issue_11680.rs
 
-extern crate "issue-11680" as other;
+extern crate issue_11680 as other;
 
 fn main() {
     let _b = other::Foo::Bar(1);

src/test/compile-fail/issue-12612.rs

@@ -8,9 +8,9 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// aux-build:issue-12612-1.rs
+// aux-build:issue_12612_1.rs
 
-extern crate "issue-12612-1" as foo;
+extern crate issue_12612_1 as foo;
 
 use foo::bar;
 

src/test/compile-fail/issue-16725.rs

@@ -8,9 +8,9 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// aux-build:issue-16725.rs
+// aux-build:issue_16725.rs
 
-extern crate "issue-16725" as foo;
+extern crate issue_16725 as foo;
 
 fn main() {
     unsafe { foo::bar(); }

src/test/compile-fail/issue-17718-const-privacy.rs

@@ -8,9 +8,9 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// aux-build:issue-17718-const-privacy.rs
+// aux-build:issue_17718_const_privacy.rs
 
-extern crate "issue-17718-const-privacy" as other;
+extern crate issue_17718_const_privacy as other;
 
 use a::B; //~ ERROR: const `B` is private
 use other::{

src/test/compile-fail/issue-21202.rs

@@ -8,9 +8,9 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// aux-build:issue-21202.rs
+// aux-build:issue_21202.rs
 
-extern crate "issue-21202" as crate1;
+extern crate issue_21202 as crate1;
 
 use crate1::A;
 

src/test/compile-fail/lint-unused-extern-crate.rs

@@ -8,7 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// aux-build:lint-unused-extern-crate.rs
+// aux-build:lint_unused_extern_crate.rs
 
 #![deny(unused_extern_crates)]
 #![allow(unused_variables)]
@@ -19,12 +19,12 @@
 
 extern crate libc; //~ ERROR: unused extern crate
 
-extern crate "collections" as collecs; // no error, it is used
+extern crate collections as collecs; // no error, it is used
 
 extern crate rand; // no error, the use marks it as used
                    // even if imported objects aren't used
 
-extern crate "lint-unused-extern-crate" as other; // no error, the use * marks it as used
+extern crate lint_unused_extern_crate as other; // no error, the use * marks it as used
 
 #[allow(unused_imports)]
 use rand::isaac::IsaacRng;

src/test/compile-fail/privacy5.rs

@@ -8,9 +8,9 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// aux-build:privacy-tuple-struct.rs
+// aux-build:privacy_tuple_struct.rs
 
-extern crate "privacy-tuple-struct" as other;
+extern crate privacy_tuple_struct as other;
 
 mod a {
     pub struct A(());
@@ -101,30 +101,30 @@ fn xcrate() {
     let c = other::C(2, 3); //~ ERROR: cannot invoke tuple struct constructor
     let d = other::D(4);
 
-    let other::A(()) = a; //~ ERROR: field #1 of struct `privacy-tuple-struct::A` is private
+    let other::A(()) = a; //~ ERROR: field #1 of struct `privacy_tuple_struct::A` is private
     let other::A(_) = a;
     match a { other::A(()) => {} }
-    //~^ ERROR: field #1 of struct `privacy-tuple-struct::A` is private
+    //~^ ERROR: field #1 of struct `privacy_tuple_struct::A` is private
     match a { other::A(_) => {} }
 
     let other::B(_) = b;
-    let other::B(_b) = b; //~ ERROR: field #1 of struct `privacy-tuple-struct::B` is private
+    let other::B(_b) = b; //~ ERROR: field #1 of struct `privacy_tuple_struct::B` is private
     match b { other::B(_) => {} }
     match b { other::B(_b) => {} }
-    //~^ ERROR: field #1 of struct `privacy-tuple-struct::B` is private
+    //~^ ERROR: field #1 of struct `privacy_tuple_struct::B` is private
     match b { other::B(1) => {} other::B(_) => {} }
-    //~^ ERROR: field #1 of struct `privacy-tuple-struct::B` is private
+    //~^ ERROR: field #1 of struct `privacy_tuple_struct::B` is private
 
     let other::C(_, _) = c;
     let other::C(_a, _) = c;
-    let other::C(_, _b) = c; //~ ERROR: field #2 of struct `privacy-tuple-struct::C` is private
-    let other::C(_a, _b) = c; //~ ERROR: field #2 of struct `privacy-tuple-struct::C` is private
+    let other::C(_, _b) = c; //~ ERROR: field #2 of struct `privacy_tuple_struct::C` is private
+    let other::C(_a, _b) = c; //~ ERROR: field #2 of struct `privacy_tuple_struct::C` is private
     match c { other::C(_, _) => {} }
     match c { other::C(_a, _) => {} }
     match c { other::C(_, _b) => {} }
-    //~^ ERROR: field #2 of struct `privacy-tuple-struct::C` is private
+    //~^ ERROR: field #2 of struct `privacy_tuple_struct::C` is private
     match c { other::C(_a, _b) => {} }
-    //~^ ERROR: field #2 of struct `privacy-tuple-struct::C` is private
+    //~^ ERROR: field #2 of struct `privacy_tuple_struct::C` is private
 
     let other::D(_) = d;
     let other::D(_d) = d;

src/test/compile-fail/regions-bounded-method-type-parameters-cross-crate.rs

@@ -8,11 +8,11 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// aux-build:regions-bounded-method-type-parameters-cross-crate-lib.rs
+// aux-build:regions_bounded_method_type_parameters_cross_crate_lib.rs
 
 // Check explicit region bounds on methods in the cross crate case.
 
-extern crate "regions-bounded-method-type-parameters-cross-crate-lib" as lib;
+extern crate regions_bounded_method_type_parameters_cross_crate_lib as lib;
 
 use lib::Inv;
 use lib::MaybeOwned;

src/test/compile-fail/static-array-across-crate.rs

@@ -10,7 +10,7 @@
 
 // aux-build:pub_static_array.rs
 
-extern crate "pub_static_array" as array;
+extern crate pub_static_array as array;
 
 use array::ARRAY;
 

src/test/compile-fail/struct-field-privacy.rs

@@ -8,9 +8,9 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// aux-build:struct-field-privacy.rs
+// aux-build:struct_field_privacy.rs
 
-extern crate "struct-field-privacy" as xc;
+extern crate struct_field_privacy as xc;
 
 struct A {
     a: isize,
@@ -37,11 +37,11 @@ fn test(a: A, b: inner::A, c: inner::B, d: xc::A, e: xc::B) {
     c.a;
     c.b; //~ ERROR: field `b` of struct `inner::B` is private
 
-    d.a; //~ ERROR: field `a` of struct `struct-field-privacy::A` is private
+    d.a; //~ ERROR: field `a` of struct `struct_field_privacy::A` is private
     d.b;
 
     e.a;
-    e.b; //~ ERROR: field `b` of struct `struct-field-privacy::B` is private
+    e.b; //~ ERROR: field `b` of struct `struct_field_privacy::B` is private
 }
 
 fn main() {}

src/test/compile-fail/suggest-private-fields.rs

@@ -8,9 +8,9 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// aux-build:struct-field-privacy.rs
+// aux-build:struct_field_privacy.rs
 
-extern crate "struct-field-privacy" as xc;
+extern crate struct_field_privacy as xc;
 
 use xc::B;
 
@@ -22,9 +22,9 @@ struct A {
 fn main () {
     // external crate struct
     let k = B {
-        aa: 20, //~ ERROR structure `struct-field-privacy::B` has no field named `aa`
+        aa: 20, //~ ERROR structure `struct_field_privacy::B` has no field named `aa`
         //~^ HELP did you mean `a`?
-        bb: 20, //~ ERROR structure `struct-field-privacy::B` has no field named `bb`
+        bb: 20, //~ ERROR structure `struct_field_privacy::B` has no field named `bb`
     };
     // local crate struct
     let l = A {

src/test/compile-fail/trait-safety-trait-impl-cc.rs

@@ -8,12 +8,12 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// aux-build:trait-safety-lib.rs
+// aux-build:trait_safety_lib.rs
 
 // Check that unsafe traits require unsafe impls and that inherent
 // impls cannot be unsafe.
 
-extern crate "trait-safety-lib" as lib;
+extern crate trait_safety_lib as lib;
 
 struct Bar;
 impl lib::Foo for Bar { //~ ERROR requires an `unsafe impl` declaration

src/test/compile-fail/typeck-default-trait-impl-cross-crate-coherence.rs

@@ -8,14 +8,14 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// aux-build:typeck-default-trait-impl-cross-crate-coherence-lib.rs
+// aux-build:typeck_default_trait_impl_cross_crate_coherence_lib.rs
 
 // Test that we do not consider associated types to be sendable without
 // some applicable trait bound (and we don't ICE).
 
 #![feature(optin_builtin_traits)]
 
-extern crate "typeck-default-trait-impl-cross-crate-coherence-lib" as lib;
+extern crate typeck_default_trait_impl_cross_crate_coherence_lib as lib;
 
 use lib::DefaultedTrait;
 

src/test/compile-fail/unreachable-variant.rs

@@ -8,9 +8,9 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// aux-build:unreachable-variant.rs
+// aux-build:unreachable_variant.rs
 
-extern crate "unreachable-variant" as other;
+extern crate unreachable_variant as other;
 
 fn main() {
     let _x = other::super_sekrit::sooper_sekrit::baz; //~ ERROR is private

src/test/parse-fail/bad-lit-suffixes.rs

@@ -11,6 +11,7 @@
 
 extern crate
     "foo"suffix //~ ERROR extern crate name with a suffix is illegal
+                //~^ WARNING: obsolete syntax
      as foo;
 
 extern

src/test/parse-fail/extern-crate-as-no-string-help.rs

@@ -1,15 +0,0 @@
-// Copyright 2014 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.
-
-// Tests that the proper help is displayed in the error message
-
-extern crate foo as bar;
-//~^ ERROR expected `;`, found `as`
-//~^^ HELP perhaps you meant to enclose the crate name `foo` in a string?

src/test/parse-fail/extern-foreign-crate.rs

@@ -11,4 +11,4 @@
 // Verifies that the expected token errors for `extern crate` are
 // raised
 
-extern crate foo {} //~ERROR expected `;`, found `{`
+extern crate foo {} //~ERROR expected one of `;` or `as`, found `{`

src/test/pretty/issue-4264.pp

@@ -3,7 +3,7 @@
 #[prelude_import]
 use std::prelude::v1::*;
 #[macro_use]
-extern crate "std" as std;
+extern crate std as std;
 // Copyright 2014 The Rust Project Developers. See the COPYRIGHT
 // file at the top-level directory of this distribution and at
 // http://rust-lang.org/COPYRIGHT.

src/test/pretty/raw-str-nonexpr.rs

@@ -13,6 +13,6 @@
 #![feature(asm)]
 
 #[cfg(foo = r#"just parse this"#)]
-extern crate r##"blah"## as blah;
+extern crate blah as blah;
 
 fn main() { unsafe { asm!(r###"blah"###); } }

src/test/run-make/weird-output-filenames/Makefile

@@ -12,4 +12,4 @@ all:
 		| grep "invalid character.*in crate name:"
 	cp foo.rs $(TMPDIR)/-foo.rs
 	$(RUSTC) $(TMPDIR)/-foo.rs 2>&1 \
-		| grep "crate name cannot start with a hyphen:"
+		| grep "soon cannot contain hyphens:"

src/test/run-pass/coherence-bigint-int.rs

@@ -8,11 +8,11 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// aux-build:coherence-lib.rs
+// aux-build:coherence_lib.rs
 
 // pretty-expanded FIXME #23616
 
-extern crate "coherence-lib" as lib;
+extern crate coherence_lib as lib;
 use lib::Remote1;
 
 pub struct BigInt;

src/test/run-pass/coherence-bigint-vecint.rs

@@ -8,11 +8,11 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// aux-build:coherence-lib.rs
+// aux-build:coherence_lib.rs
 
 // pretty-expanded FIXME #23616
 
-extern crate "coherence-lib" as lib;
+extern crate coherence_lib as lib;
 use lib::Remote1;
 
 pub struct BigInt;

src/test/run-pass/coherence-blanket.rs

@@ -8,11 +8,11 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// aux-build:coherence-lib.rs
+// aux-build:coherence_lib.rs
 
 // pretty-expanded FIXME #23616
 
-extern crate "coherence-lib" as lib;
+extern crate coherence_lib as lib;
 use lib::Remote1;
 
 pub trait Local {

src/test/run-pass/coherence-covered-type-parameter.rs

@@ -8,11 +8,11 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// aux-build:coherence-lib.rs
+// aux-build:coherence_lib.rs
 
 // pretty-expanded FIXME #23616
 
-extern crate "coherence-lib" as lib;
+extern crate coherence_lib as lib;
 use lib::Remote;
 
 struct Foo<T>(T);

src/test/run-pass/coherence-cow-1.rs

@@ -8,14 +8,14 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// aux-build:coherence-lib.rs
+// aux-build:coherence_lib.rs
 
 // Test that it's ok for T to appear first in the self-type, as long
 // as it's covered somewhere.
 
 // pretty-expanded FIXME #23616
 
-extern crate "coherence-lib" as lib;
+extern crate coherence_lib as lib;
 use lib::{Remote,Pair};
 
 pub struct Cover<T>(T);

src/test/run-pass/coherence-cow-2.rs

@@ -8,14 +8,14 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// aux-build:coherence-lib.rs
+// aux-build:coherence_lib.rs
 
 // Test that it's ok for T to appear second in the self-type, as long
 // as it's covered somewhere.
 
 // pretty-expanded FIXME #23616
 
-extern crate "coherence-lib" as lib;
+extern crate coherence_lib as lib;
 use lib::{Remote,Pair};
 
 pub struct Cover<T>(T);

src/test/run-pass/coherence-iterator-vec-any-elem.rs

@@ -8,11 +8,11 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// aux-build:coherence-lib.rs
+// aux-build:coherence_lib.rs
 
 // pretty-expanded FIXME #23616
 
-extern crate "coherence-lib" as lib;
+extern crate coherence_lib as lib;
 use lib::Remote1;
 
 struct Foo<T>(T);

src/test/run-pass/coherence-iterator-vec.rs

@@ -8,11 +8,11 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// aux-build:coherence-lib.rs
+// aux-build:coherence_lib.rs
 
 // pretty-expanded FIXME #23616
 
-extern crate "coherence-lib" as lib;
+extern crate coherence_lib as lib;
 use lib::Remote1;
 
 struct Foo<T>(T);

src/test/run-pass/coherence-local-1.rs

@@ -8,11 +8,11 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// aux-build:coherence-lib.rs
+// aux-build:coherence_lib.rs
 
 // pretty-expanded FIXME #23616
 
-extern crate "coherence-lib" as lib;
+extern crate coherence_lib as lib;
 use lib::Remote;
 
 struct Local;

src/test/run-pass/coherence-local-2.rs

@@ -8,11 +8,11 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// aux-build:coherence-lib.rs
+// aux-build:coherence_lib.rs
 
 // pretty-expanded FIXME #23616
 
-extern crate "coherence-lib" as lib;
+extern crate coherence_lib as lib;
 use lib::Remote;
 
 struct Local<T>(T);

src/test/run-pass/issue-12612.rs

@@ -8,13 +8,13 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// aux-build:issue-12612-1.rs
-// aux-build:issue-12612-2.rs
+// aux-build:issue_12612_1.rs
+// aux-build:issue_12612_2.rs
 
 // pretty-expanded FIXME #23616
 
-extern crate "issue-12612-1" as foo;
-extern crate "issue-12612-2" as bar;
+extern crate issue_12612_1 as foo;
+extern crate issue_12612_2 as bar;
 
 mod test {
     use bar::baz;

src/test/run-pass/trait-safety-ok-cc.rs

@@ -8,13 +8,13 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// aux-build:trait-safety-lib.rs
+// aux-build:trait_safety_lib.rs
 
 // Simple smoke test that unsafe traits can be compiled across crates.
 
 // pretty-expanded FIXME #23616
 
-extern crate "trait-safety-lib" as lib;
+extern crate trait_safety_lib as lib;
 
 use lib::Foo;