src/test/compile-fail/issue-5067.rs

   1 // Copyright 2016 The Rust Project Developers. See the COPYRIGHT
   2 // file at the top-level directory of this distribution and at
   3 // http://rust-lang.org/COPYRIGHT.
   4 //
   5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
   6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
   7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
   8 // option. This file may not be copied, modified, or distributed
   9 // except according to those terms.
  10
  11 #![allow(unused_macros)]
  12
  13 macro_rules! foo {
  14     ( $()* ) => {};
  15     //~^ ERROR repetition matches empty token tree
  16     ( $()+ ) => {};
  17     //~^ ERROR repetition matches empty token tree
  18
  19     ( $(),* ) => {}; // PASS
  20     ( $(),+ ) => {}; // PASS
  21
  22     ( [$()*] ) => {};
  23     //~^ ERROR repetition matches empty token tree
  24     ( [$()+] ) => {};
  25     //~^ ERROR repetition matches empty token tree
  26
  27     ( [$(),*] ) => {}; // PASS
  28     ( [$(),+] ) => {}; // PASS
  29
  30     ( $($()* $(),* $(a)* $(a),* )* ) => {};
  31     //~^ ERROR repetition matches empty token tree
  32     ( $($()* $(),* $(a)* $(a),* )+ ) => {};
  33     //~^ ERROR repetition matches empty token tree
  34
  35     ( $(a     $(),* $(a)* $(a),* )* ) => {}; // PASS
  36     ( $($(a)+ $(),* $(a)* $(a),* )+ ) => {}; // PASS
  37
  38     ( $(a $()+)* ) => {};
  39     //~^ ERROR repetition matches empty token tree
  40     ( $(a $()*)+ ) => {};
  41     //~^ ERROR repetition matches empty token tree
  42 }
  43
  44
  45 // --- Original Issue --- //
  46
  47 macro_rules! make_vec {
  48     (a $e1:expr $($(, a $e2:expr)*)*) => ([$e1 $($(, $e2)*)*]);
  49     //~^ ERROR repetition matches empty token tree
  50 }
  51
  52 fn main() {
  53     let _ = make_vec![a 1, a 2, a 3];
  54 }
  55
  56
  57 // --- Minified Issue --- //
  58
  59 macro_rules! m {
  60     ( $()* ) => {}
  61     //~^ ERROR repetition matches empty token tree
  62 }
  63
  64 m!();