tokio-macros: add documentation about re-naming the tokio dependency

tokio-macros/src/lib.rs

@@ -55,6 +55,14 @@ use proc_macro::TokenStream;
 ///     println!("Hello world");
 /// }
 /// ```
+///
+/// ### NOTE:
+///
+/// If you rename the tokio crate in your dependencies this macro
+/// will not work. If you must rename the 0.2 version of tokio because
+/// you're also using the 0.1 version of tokio, you _must_ make the
+/// tokio 0.2 crate available as `tokio` in the module where this
+/// macro is expanded.
 #[proc_macro_attribute]
 #[cfg(not(test))] // Work around for rust-lang/rust#62127
 pub fn main_threaded(args: TokenStream, item: TokenStream) -> TokenStream {
@@ -91,6 +99,14 @@ pub fn main_threaded(args: TokenStream, item: TokenStream) -> TokenStream {
 ///     println!("Hello world");
 /// }
 /// ```
+///
+/// ### NOTE:
+///
+/// If you rename the tokio crate in your dependencies this macro
+/// will not work. If you must rename the 0.2 version of tokio because
+/// you're also using the 0.1 version of tokio, you _must_ make the
+/// tokio 0.2 crate available as `tokio` in the module where this
+/// macro is expanded.
 #[proc_macro_attribute]
 #[cfg(not(test))] // Work around for rust-lang/rust#62127
 pub fn main(args: TokenStream, item: TokenStream) -> TokenStream {
@@ -117,6 +133,14 @@ pub fn main(args: TokenStream, item: TokenStream) -> TokenStream {
 ///     println!("Hello world");
 /// }
 /// ```
+///
+/// ### NOTE:
+///
+/// If you rename the tokio crate in your dependencies this macro
+/// will not work. If you must rename the 0.2 version of tokio because
+/// you're also using the 0.1 version of tokio, you _must_ make the
+/// tokio 0.2 crate available as `tokio` in the module where this
+/// macro is expanded.
 #[proc_macro_attribute]
 #[cfg(not(test))] // Work around for rust-lang/rust#62127
 pub fn main_basic(args: TokenStream, item: TokenStream) -> TokenStream {
@@ -149,6 +173,14 @@ pub fn main_basic(args: TokenStream, item: TokenStream) -> TokenStream {
 ///     assert!(true);
 /// }
 /// ```
+///
+/// ### NOTE:
+///
+/// If you rename the tokio crate in your dependencies this macro
+/// will not work. If you must rename the 0.2 version of tokio because
+/// you're also using the 0.1 version of tokio, you _must_ make the
+/// tokio 0.2 crate available as `tokio` in the module where this
+/// macro is expanded.
 #[proc_macro_attribute]
 pub fn test_threaded(args: TokenStream, item: TokenStream) -> TokenStream {
     entry::test(args, item, true)
@@ -180,6 +212,14 @@ pub fn test_threaded(args: TokenStream, item: TokenStream) -> TokenStream {
 ///     assert!(true);
 /// }
 /// ```
+///
+/// ### NOTE:
+///
+/// If you rename the tokio crate in your dependencies this macro
+/// will not work. If you must rename the 0.2 version of tokio because
+/// you're also using the 0.1 version of tokio, you _must_ make the
+/// tokio 0.2 crate available as `tokio` in the module where this
+/// macro is expanded.
 #[proc_macro_attribute]
 pub fn test(args: TokenStream, item: TokenStream) -> TokenStream {
     entry::old::test(args, item)
@@ -199,6 +239,14 @@ pub fn test(args: TokenStream, item: TokenStream) -> TokenStream {
 ///     assert!(true);
 /// }
 /// ```
+///
+/// ### NOTE:
+///
+/// If you rename the tokio crate in your dependencies this macro
+/// will not work. If you must rename the 0.2 version of tokio because
+/// you're also using the 0.1 version of tokio, you _must_ make the
+/// tokio 0.2 crate available as `tokio` in the module where this
+/// macro is expanded.
 #[proc_macro_attribute]
 pub fn test_basic(args: TokenStream, item: TokenStream) -> TokenStream {
     entry::test(args, item, false)