src/test/compile-fail/issue-21221-1.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 mod mul1 {
  12     pub trait Mul {}
  13 }
  14
  15 mod mul2 {
  16     pub trait Mul {}
  17 }
  18
  19 mod mul3 {
  20     enum Mul {
  21       Yes,
  22       No
  23     }
  24 }
  25
  26 mod mul4 {
  27     type Mul = String;
  28 }
  29
  30 mod mul5 {
  31     struct Mul{
  32         left_term: u32,
  33         right_term: u32
  34     }
  35 }
  36
  37 #[derive(Debug)]
  38 struct Foo;
  39
  40 // When we comment the next line:
  41 //use mul1::Mul;
  42
  43 // BEFORE, we got the following error for the `impl` below:
  44 //   error: use of undeclared trait name `Mul` [E0405]
  45 // AFTER, we get this message:
  46 //   error: trait `Mul` is not in scope.
  47 //   help: ...
  48 //   help: you can import several candidates into scope (`use ...;`):
  49 //   help:   `mul1::Mul`
  50 //   help:   `mul2::Mul`
  51 //   help:   `std::ops::Mul`
  52
  53 impl Mul for Foo {
  54 //~^ ERROR trait `Mul` is not in scope
  55 //~| HELP `mul1::Mul`
  56 //~| HELP `mul2::Mul`
  57 //~| HELP `std::ops::Mul`
  58 //~| HELP run `rustc --explain E0405` to see a detailed explanation
  59 //~| HELP you can import several candidates into scope (`use ...;`):
  60 }
  61
  62 // BEFORE, we got:
  63 //   error: use of undeclared type name `Mul` [E0412]
  64 // AFTER, we get:
  65 //   error: type name `Mul` is not in scope. Maybe you meant:
  66 //   help: ...
  67 //   help: you can import several candidates into scope (`use ...;`):
  68 //   help:   `mul1::Mul`
  69 //   help:   `mul2::Mul`
  70 //   help:   `mul3::Mul`
  71 //   help:   `mul4::Mul`
  72 //   help:   and 2 other candidates
  73 fn getMul() -> Mul {
  74 //~^ ERROR type name `Mul` is undefined or not in scope
  75 //~| HELP `mul1::Mul`
  76 //~| HELP `mul2::Mul`
  77 //~| HELP `mul3::Mul`
  78 //~| HELP `mul4::Mul`
  79 //~| HELP and 2 other candidates
  80 //~| HELP run `rustc --explain E0412` to see a detailed explanation
  81 //~| HELP you can import several candidates into scope (`use ...;`):
  82 }
  83
  84 // Let's also test what happens if the trait doesn't exist:
  85 impl ThisTraitReallyDoesntExistInAnyModuleReally for Foo {
  86 //~^ ERROR trait `ThisTraitReallyDoesntExistInAnyModuleReally` is not in scope
  87 //~^^ HELP run `rustc --explain E0405` to see a detailed explanation
  88 //~^^^ HELP no candidates by the name of `ThisTraitReallyDoesntExistInAnyModuleReally` found
  89 }
  90
  91 // Let's also test what happens if there's just one alternative:
  92 impl Div for Foo {
  93 //~^ ERROR trait `Div` is not in scope
  94 //~| HELP `use std::ops::Div;`
  95 //~| HELP run `rustc --explain E0405` to see a detailed explanation
  96 }
  97
  98 fn main() {
  99     let foo = Foo();
 100     println!("Hello, {:?}!", foo);
 101 }