edition: Fill in macro imports

Macros were previously imported through `#[macro_use] extern crate`,
which is basically a glob import of all macros from the crate. As of
2018 edition of Rust, `extern crate` is no longer required and macros
are imported individually like any other item from a dependency. This CL
fills in all the appropriate macro imports that will allow us to remove
our use of `extern crate` in a subsequent CL.

TEST=cargo check --all-features --tests
TEST=kokoro

Change-Id: If2ec08b06b743abf5f62677c6a9927c3d5d90a54
Reviewed-on: https://chromium-review.googlesource.com/1565546
Commit-Ready: David Tolnay <dtolnay@chromium.org>
Commit-Ready: ChromeOS CL Exonerator Bot <chromiumos-cl-exonerator@appspot.gserviceaccount.com>
Tested-by: David Tolnay <dtolnay@chromium.org>
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: David Tolnay <dtolnay@chromium.org>

1 files changed, 4 insertions, 2 deletions

diff --git a/bit_field/bit_field_derive/bit_field_derive.rs b/bit_field/bit_field_derive/bit_field_derive.rs
index 0bd0daf..e7d26cd 100644
--- a/bit_field/bit_field_derive/bit_field_derive.rs
+++ b/bit_field/bit_field_derive/bit_field_derive.rs
@@ -13,10 +13,11 @@ extern crate quote;
 extern crate syn;
 
 use proc_macro2::{Span, TokenStream};
+use quote::{quote, quote_spanned};
 use syn::parse::{Error, Result};
 use syn::{
-    Attribute, Data, DataEnum, DeriveInput, Fields, FieldsNamed, FieldsUnnamed, Ident, Lit, LitInt,
-    Meta, Type, Visibility,
+    parse_macro_input, Attribute, Data, DataEnum, DeriveInput, Fields, FieldsNamed, FieldsUnnamed,
+    Ident, Lit, LitInt, Meta, Type, Visibility,
 };
 
 /// The function that derives the actual implementation.
@@ -654,6 +655,7 @@ pub fn define_bit_field_specifiers(_input: proc_macro::TokenStream) -> proc_macr
 #[cfg(test)]
 mod tests {
     use super::*;
+    use syn::parse_quote;
 
     #[test]
     fn end_to_end() {