Build failure: crate proc_macro is private

[elihunter173]

When I try to build the project on any of machines, I get the following error. My guess is that an import was misplaced but I don't know why the CI builds wouldn't catch it.

  Downloaded version_check v0.9.2
  Downloaded proc-macro-error v1.0.3
  Downloaded proc-macro-error-attr v1.0.3
  Downloaded quote v1.0.7
  Downloaded syn-mid v0.5.0
  Downloaded unicode-xid v0.2.1
  Downloaded syn v1.0.33
  Downloaded 7 crates (301.2 KB) in 0.66s
   Compiling proc-macro2 v1.0.18
   Compiling unicode-xid v0.2.1
   Compiling version_check v0.9.2
   Compiling syn v1.0.33
   Compiling proc-macro-error-attr v1.0.3
   Compiling proc-macro-error v1.0.3
   Compiling quote v1.0.7
   Compiling syn-mid v0.5.0
   Compiling duplicate v0.0.0 (/tmp/duplicate)
error[E0603]: crate `proc_macro` is private
   --> src/parse_utils.rs:3:2
    |
3   |     proc_macro::{Punct, Spacing},
    |     ^^^^^^^^^^ private crate
    |
note: the crate `proc_macro` is defined here
   --> /home/eli/.cargo/registry/src/github.com-1ecc6299db9ec823/proc-macro-error-1.0.3/src/lib.rs:256:1
    |
256 | extern crate proc_macro;
    | ^^^^^^^^^^^^^^^^^^^^^^^^

warning: unused import: `proc_macro_error::*`
 --> src/parse.rs:6:5
  |
6 | use proc_macro_error::*;
  |     ^^^^^^^^^^^^^^^^^^^
  |
  = note: `#[warn(unused_imports)]` on by default

warning: unused import: `*`
 --> src/parse_utils.rs:4:2
  |
4 |     *,
  |     ^

error: aborting due to previous error; 2 warnings emitted

For more information about this error, try `rustc --explain E0603`.
error: could not compile `duplicate`.

To learn more, run the command again with --verbose.

This patch should fix it. I'll submit a PR after I test it and also replace the wildcard imports.

index 6a7fd06..96061a7 100644
--- a/src/parse_utils.rs
+++ b/src/parse_utils.rs
@@ -1,8 +1,5 @@
-use proc_macro::{Delimiter, Group, Span, TokenTree};
-use proc_macro_error::{
-	proc_macro::{Punct, Spacing},
-	*,
-};
+use proc_macro::{Delimiter, Group, Punct, Spacing, Span, TokenTree};
+use proc_macro_error::*;
 
 /// Tries to parse a valid group from the given token stream iterator, returning
 /// the group if successful.

[Emoun]

@elihunter173 thank you for the issue and PR. I will have a look at them later today.
This is indeed weird, as I'm using the crate in one of my other projects and have not encountered this before.

[Emoun]

This actually seems to be a problem with proc_macro_error v1.0.3.
v1.0.2 compiles fine on my machine, but updating my lock file will cause me this error too.

It seems proc_macro_error had a hidden re-export of proc_macro that I accidentally used instead of using the crate directly.

I made an issue with proc_macro_error to make them aware of this.

[Emoun]

PR merged.

[Emoun]

@elihunter173 I have release v0.2.5 with your fix.

Thanks for reporting the issue and contributing the PR. If you need help, have feature requests, or find more bugs feel free to open more issues/PRs.