Macro import does not bring dependent macros in scope in 2018 edition

[starkat99]

Importing a macro from a crate in 2018 edition that invokes other macros does not bring those macros in scope. It's easy enough to make work by importing the other macros of course, but surprising behavior anyway, especially when it involves importing macros that won't actually be referenced anywhere in the file itself, only through invocations.

Example (using clap 2.32):

use clap::app_from_crate;
fn main() {
    let _args = app_from_crate!().get_matches();
}

will produce the following error

error: cannot find macro `crate_name!` in this scope
 --> src\main.rs:5:17
  |
5 |     let _args = app_from_crate!().get_matches();
  |                 ^^^^^^^^^^^^^^^^^
  |
  = note: this error originates in a macro outside of the current crate (in Nightly builds, run with -Z external-macro-backtrace for more info)

[Arnavion]

I believe this is by design for macro_rules macros. Macros 2.0 are the only ones that have def-site-scoped dependencies.

Edit: The alternative is that clap annotates the dependency macros with local_inner_macros, as described in #51496

[jonas-schievink]

local_inner_macros seems to fix this, so closing.