src/test/ui/suggestions/expected-boxed-future-isnt-pinned.stderr

   1 error[E0308]: mismatched types
   2   --> $DIR/expected-boxed-future-isnt-pinned.rs:11:5
   3    |
   4 LL | fn foo<F: Future<Output=i32> + Send + 'static>(x: F) -> BoxFuture<'static, i32> {
   5    |        - this type parameter                            ----------------------- expected `Pin<Box<(dyn Future<Output = i32> + Send + 'static)>>` because of return type
   6 LL |     // We could instead use an `async` block, but this way we have no std spans.
   7 LL |     x
   8    |     ^ expected struct `Pin`, found type parameter `F`
   9    |
  10    = note:      expected struct `Pin<Box<(dyn Future<Output = i32> + Send + 'static)>>`
  11            found type parameter `F`
  12 help: you need to pin and box this expression
  13    |
  14 LL |     Box::pin(x)
  15    |     +++++++++ +
  16
  17 error[E0308]: mismatched types
  18   --> $DIR/expected-boxed-future-isnt-pinned.rs:15:5
  19    |
  20 LL | fn bar<F: Future<Output=i32> + Send + 'static>(x: F) -> BoxFuture<'static, i32> {
  21    |                                                         ----------------------- expected `Pin<Box<(dyn Future<Output = i32> + Send + 'static)>>` because of return type
  22 LL |     Box::new(x)
  23    |     ^^^^^^^^^^^ expected struct `Pin`, found struct `Box`
  24    |
  25    = note: expected struct `Pin<Box<(dyn Future<Output = i32> + Send + 'static)>>`
  26               found struct `Box<F>`
  27    = help: use `Box::pin`
  28
  29 error[E0308]: mismatched types
  30   --> $DIR/expected-boxed-future-isnt-pinned.rs:19:14
  31    |
  32 LL | fn baz<F: Future<Output=i32> + Send + 'static>(x: F) -> BoxFuture<'static, i32> {
  33    |        - this type parameter
  34 LL |     Pin::new(x)
  35    |     -------- ^ expected struct `Box`, found type parameter `F`
  36    |     |
  37    |     help: use `Box::pin` to pin and box this expression: `Box::pin`
  38    |
  39    = note:      expected struct `Box<dyn Future<Output = i32> + Send>`
  40            found type parameter `F`
  41
  42 error[E0277]: `dyn Future<Output = i32> + Send` cannot be unpinned
  43   --> $DIR/expected-boxed-future-isnt-pinned.rs:19:5
  44    |
  45 LL |     Pin::new(x)
  46    |     ^^^^^^^^ the trait `Unpin` is not implemented for `dyn Future<Output = i32> + Send`
  47    |
  48    = note: consider using `Box::pin`
  49 note: required by a bound in `Pin::<P>::new`
  50   --> $SRC_DIR/core/src/pin.rs:LL:COL
  51    |
  52 LL | impl<P: Deref<Target: Unpin>> Pin<P> {
  53    |                       ^^^^^ required by this bound in `Pin::<P>::new`
  54
  55 error[E0277]: `dyn Future<Output = i32> + Send` cannot be unpinned
  56   --> $DIR/expected-boxed-future-isnt-pinned.rs:24:5
  57    |
  58 LL |     Pin::new(Box::new(x))
  59    |     ^^^^^^^^ the trait `Unpin` is not implemented for `dyn Future<Output = i32> + Send`
  60    |
  61    = note: consider using `Box::pin`
  62 note: required by a bound in `Pin::<P>::new`
  63   --> $SRC_DIR/core/src/pin.rs:LL:COL
  64    |
  65 LL | impl<P: Deref<Target: Unpin>> Pin<P> {
  66    |                       ^^^^^ required by this bound in `Pin::<P>::new`
  67
  68 error[E0308]: mismatched types
  69   --> $DIR/expected-boxed-future-isnt-pinned.rs:28:5
  70    |
  71 LL |   fn zap() -> BoxFuture<'static, i32> {
  72    |               ----------------------- expected `Pin<Box<(dyn Future<Output = i32> + Send + 'static)>>` because of return type
  73 LL | /     async {
  74 LL | |         42
  75 LL | |     }
  76    | |_____^ expected struct `Pin`, found opaque type
  77    |
  78   ::: $SRC_DIR/core/src/future/mod.rs:LL:COL
  79    |
  80 LL |   pub const fn from_generator<T>(gen: T) -> impl Future<Output = T::Return>
  81    |                                             ------------------------------- the found opaque type
  82    |
  83    = note:   expected struct `Pin<Box<(dyn Future<Output = i32> + Send + 'static)>>`
  84            found opaque type `impl Future`
  85 help: you need to pin and box this expression
  86    |
  87 LL ~     Box::pin(async {
  88 LL |         42
  89 LL ~     })
  90    |
  91
  92 error: aborting due to 6 previous errors
  93
  94 Some errors have detailed explanations: E0277, E0308.
  95 For more information about an error, try `rustc --explain E0277`.