src/test/mir-opt/simplify_try.rs

   1 // compile-flags: -Zunsound-mir-opts
   2 // EMIT_MIR simplify_try.try_identity.SimplifyArmIdentity.diff
   3 // EMIT_MIR simplify_try.try_identity.SimplifyBranchSame.after.mir
   4 // EMIT_MIR simplify_try.try_identity.SimplifyLocals.after.mir
   5 // EMIT_MIR simplify_try.try_identity.DestinationPropagation.diff
   6
   7
   8 fn into_result<T, E>(r: Result<T, E>) -> Result<T, E> {
   9     r
  10 }
  11
  12 fn from_error<T, E>(e: E) -> Result<T, E> {
  13     Err(e)
  14 }
  15
  16 // This was written to the `?` from `try_trait`,
  17 // but `try_trait_v2` uses a different structure,
  18 // so the relevant desugar is copied inline
  19 // in order to keep the test testing the same thing.
  20 fn try_identity(x: Result<u32, i32>) -> Result<u32, i32> {
  21     let y = match into_result(x) {
  22         Err(e) => return from_error(From::from(e)),
  23         Ok(v) => v,
  24     };
  25     Ok(y)
  26 }
  27
  28 fn main() {
  29     let _ = try_identity(Ok(0));
  30 }