Switch to the newer Try trait API (#221)

Author: GabrielMajeri

src/lib.rs

@@ -25,7 +25,8 @@
 
 #![cfg_attr(feature = "exts", feature(allocator_api, alloc_layout_extra))]
 #![feature(auto_traits)]
-#![feature(try_trait)]
+#![feature(control_flow_enum)]
+#![feature(try_trait_v2)]
 #![feature(abi_efiapi)]
 #![feature(negative_impls)]
 #![feature(const_panic)]

src/result/status.rs

@@ -1,6 +1,6 @@
 use super::{Completion, Error, Result};
-use core::fmt::Debug;
-use core::ops;
+use core::ops::{ControlFlow, FromResidual, Try};
+use core::{fmt::Debug, num::NonZeroUsize};
 
 /// Bit indicating that an UEFI status code is an error
 const ERROR_BIT: usize = 1 << (core::mem::size_of::<usize>() * 8 - 1);
@@ -162,29 +162,35 @@ impl Status {
     }
 }
 
-// An UEFI status is equivalent to a Result with no data or rerror payload
-
+// An UEFI status is equivalent to a Result with no data or error payload
 impl From<Status> for Result<(), ()> {
     #[inline]
     fn from(status: Status) -> Result<(), ()> {
         status.into_with(|| (), |_| ())
     }
 }
 
-impl ops::Try for Status {
-    type Ok = Completion<()>;
-    type Error = Error<()>;
+pub struct StatusResidual(NonZeroUsize);
+
+impl Try for Status {
+    type Output = Completion<()>;
+    type Residual = StatusResidual;
 
-    fn into_result(self) -> Result<(), ()> {
-        self.into()
+    fn branch(self) -> ControlFlow<Self::Residual, Self::Output> {
+        match NonZeroUsize::new(self.0) {
+            Some(r) => ControlFlow::Break(StatusResidual(r)),
+            None => ControlFlow::Continue(Completion::from(self)),
+        }
     }
 
-    fn from_error(error: Self::Error) -> Self {
-        error.status()
+    fn from_output(output: Self::Output) -> Self {
+        output.status()
     }
+}
 
-    fn from_ok(ok: Self::Ok) -> Self {
-        ok.status()
+impl FromResidual for Status {
+    fn from_residual(r: StatusResidual) -> Self {
+        Status(r.0.into())
     }
 }
 

uefi-test-runner/src/proto/pi/mp.rs

@@ -56,14 +56,14 @@ fn test_get_processor_info(mps: &MpServices) {
     assert_eq!(cpu2.processor_id, 2);
 
     // Check that only CPU 0 is BSP
-    assert_eq!(cpu0.is_bsp(), true);
-    assert_eq!(cpu1.is_bsp(), false);
-    assert_eq!(cpu2.is_bsp(), false);
+    assert!(cpu0.is_bsp());
+    assert!(!cpu1.is_bsp());
+    assert!(!cpu2.is_bsp());
 
     // Check that only the second CPU is disabled
-    assert_eq!(cpu0.is_enabled(), true);
-    assert_eq!(cpu1.is_enabled(), false);
-    assert_eq!(cpu2.is_enabled(), true);
+    assert!(cpu0.is_enabled());
+    assert!(!cpu1.is_enabled());
+    assert!(cpu2.is_enabled());
 
     // Enable second CPU back
     mps.enable_disable_ap(1, true, None).unwrap().unwrap();
@@ -138,12 +138,12 @@ fn test_enable_disable_ap(mps: &MpServices) {
         .unwrap()
         .unwrap();
     let cpu1 = mps.get_processor_info(1).unwrap().unwrap();
-    assert_eq!(cpu1.is_healthy(), false);
+    assert!(!cpu1.is_healthy());
 
     // Mark second CPU as healthy again and check it's status
     mps.enable_disable_ap(1, true, Some(true)).unwrap().unwrap();
     let cpu1 = mps.get_processor_info(1).unwrap().unwrap();
-    assert_eq!(cpu1.is_healthy(), true);
+    assert!(cpu1.is_healthy());
 }
 
 fn test_switch_bsp_and_who_am_i(mps: &MpServices) {