src/test/ui/closures/2229_closure_analysis/migrations/precise.rs

   1 #![deny(disjoint_capture_drop_reorder)]
   2 //~^ NOTE: the lint level is defined here
   3
   4 #[derive(Debug)]
   5 struct Foo(i32);
   6 impl Drop for Foo {
   7     fn drop(&mut self) {
   8         println!("{:?} dropped", self.0);
   9     }
  10 }
  11
  12 struct ConstainsDropField(Foo, Foo);
  13
  14 #[derive(Debug)]
  15 struct ContainsAndImplsDrop(Foo);
  16 impl Drop for ContainsAndImplsDrop {
  17     fn drop(&mut self) {
  18         println!("{:?} dropped", self.0);
  19     }
  20 }
  21
  22 // Test that even if all paths starting at root variable that implement Drop are captured,
  23 // the lint is triggered if the root variable implements drop and isn't captured.
  24 fn test_precise_analysis_parent_root_impl_drop_not_captured() {
  25     let t = ContainsAndImplsDrop(Foo(10));
  26
  27     let c = || {
  28     //~^ERROR: drop order affected for closure because of `capture_disjoint_fields`
  29     //~| NOTE: drop(&(t));
  30         let _t = t.0;
  31     };
  32
  33     c();
  34 }
  35
  36 // Test that lint is triggered if a path that implements Drop is not captured by move
  37 fn test_precise_analysis_drop_paths_not_captured_by_move() {
  38     let t = ConstainsDropField(Foo(10), Foo(20));
  39
  40     let c = || {
  41     //~^ERROR: drop order affected for closure because of `capture_disjoint_fields`
  42     //~| NOTE: drop(&(t));
  43         let _t = t.0;
  44         let _t = &t.1;
  45     };
  46
  47     c();
  48 }
  49
  50 struct S;
  51 impl Drop for S {
  52     fn drop(&mut self) {
  53     }
  54 }
  55
  56 struct T(S, S);
  57 struct U(T, T);
  58
  59 // Test precise analysis for the lint works with paths longer than one.
  60 fn test_precise_analysis_long_path_missing() {
  61     let u = U(T(S, S), T(S, S));
  62
  63     let c = || {
  64     //~^ERROR: drop order affected for closure because of `capture_disjoint_fields`
  65     //~| NOTE: drop(&(u));
  66         let _x = u.0.0;
  67         let _x = u.0.1;
  68         let _x = u.1.0;
  69     };
  70
  71     c();
  72 }
  73
  74 fn main() {
  75     test_precise_analysis_parent_root_impl_drop_not_captured();
  76     test_precise_analysis_drop_paths_not_captured_by_move();
  77     test_precise_analysis_long_path_missing();
  78 }