src/test/ui/span/lint-unused-unsafe.rs

   1 // Copyright 2013 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 // Exercise the unused_unsafe attribute in some positive and negative cases
  12
  13 #![allow(dead_code)]
  14 #![deny(unused_unsafe)]
  15
  16
  17 mod foo {
  18     extern {
  19         pub fn bar();
  20     }
  21 }
  22
  23 fn callback<T, F>(_f: F) -> T where F: FnOnce() -> T { panic!() }
  24 unsafe fn unsf() {}
  25
  26 fn bad1() { unsafe {} }                  //~ ERROR: unnecessary `unsafe` block
  27 fn bad2() { unsafe { bad1() } }          //~ ERROR: unnecessary `unsafe` block
  28 unsafe fn bad3() { unsafe {} }           //~ ERROR: unnecessary `unsafe` block
  29 fn bad4() { unsafe { callback(||{}) } }  //~ ERROR: unnecessary `unsafe` block
  30 unsafe fn bad5() { unsafe { unsf() } }   //~ ERROR: unnecessary `unsafe` block
  31 fn bad6() {
  32     unsafe {                             // don't put the warning here
  33         unsafe {                         //~ ERROR: unnecessary `unsafe` block
  34             unsf()
  35         }
  36     }
  37 }
  38 unsafe fn bad7() {
  39     unsafe {                             //~ ERROR: unnecessary `unsafe` block
  40         unsafe {                         //~ ERROR: unnecessary `unsafe` block
  41             unsf()
  42         }
  43     }
  44 }
  45
  46 unsafe fn good0() { unsf() }
  47 fn good1() { unsafe { unsf() } }
  48 fn good2() {
  49     /* bug uncovered when implementing warning about unused unsafe blocks. Be
  50        sure that when purity is inherited that the source of the unsafe-ness
  51        is tracked correctly */
  52     unsafe {
  53         unsafe fn what() -> Vec<String> { panic!() }
  54
  55         callback(|| {
  56             what();
  57         });
  58     }
  59 }
  60
  61 unsafe fn good3() { foo::bar() }
  62 fn good4() { unsafe { foo::bar() } }
  63
  64 #[allow(unused_unsafe)] fn allowed() { unsafe {} }
  65
  66 fn main() {}