ci: use stable toolchain for compiling xtask

.github/workflows/rust.yml

@@ -27,11 +27,15 @@ jobs:
         cp /usr/share/AAVMF/AAVMF_CODE.fd uefi-test-runner/QEMU_EFI-pflash.raw
         cp /usr/share/AAVMF/AAVMF_VARS.fd uefi-test-runner/vars-template-pflash.raw
 
+    - name: Install stable
+      uses: actions-rs/toolchain@v1
+      with:
+          toolchain: stable
+
     - name: Install latest nightly
       uses: actions-rs/toolchain@v1
       with:
           toolchain: nightly
-          override: true
           components: rust-src
       # TODO: cache Rust binaries
 
@@ -54,11 +58,15 @@ jobs:
         sudo apt-get update
         sudo apt-get install qemu-system-x86 ovmf -y
 
+    - name: Install stable
+      uses: actions-rs/toolchain@v1
+      with:
+          toolchain: stable
+
     - name: Install latest nightly
       uses: actions-rs/toolchain@v1
       with:
           toolchain: nightly
-          override: true
           components: rust-src
       # TODO: cache Rust binaries
 
@@ -97,11 +105,15 @@ jobs:
         curl -o uefi-test-runner/OVMF32_CODE.fd https://raw.githubusercontent.com/retrage/edk2-nightly/${EDK2_NIGHTLY_COMMIT}/bin/RELEASEIa32_OVMF_CODE.fd
         curl -o uefi-test-runner/OVMF32_VARS.fd https://raw.githubusercontent.com/retrage/edk2-nightly/${EDK2_NIGHTLY_COMMIT}/bin/RELEASEIa32_OVMF_VARS.fd
 
+    - name: Install stable
+      uses: actions-rs/toolchain@v1
+      with:
+          toolchain: stable
+
     - name: Install latest nightly
       uses: actions-rs/toolchain@v1
       with:
           toolchain: nightly
-          override: true
           components: rust-src
       # TODO: cache Rust binaries
 
@@ -119,13 +131,17 @@ jobs:
       - name: Checkout sources
         uses: actions/checkout@v2
 
+      - name: Install stable
+        uses: actions-rs/toolchain@v1
+        with:
+            toolchain: stable
+
       - name: Install latest nightly
         uses: actions-rs/toolchain@v1
         with:
             profile: minimal
             toolchain: nightly
             components: rust-src
-            override: true
 
       - name: Run cargo test
         run: cargo xtask test
@@ -137,13 +153,17 @@ jobs:
       - name: Checkout sources
         uses: actions/checkout@v2
 
+      - name: Install stable
+        uses: actions-rs/toolchain@v1
+        with:
+            toolchain: stable
+
       - name: Install latest nightly
         uses: actions-rs/toolchain@v1
         with:
             profile: minimal
             toolchain: nightly
             components: rustfmt, clippy, rust-src
-            override: true
 
       - name: Run cargo fmt
         uses: actions-rs/cargo@v1
@@ -164,6 +184,11 @@ jobs:
       - name: Checkout sources
         uses: actions/checkout@v2
 
+      - name: Install stable
+        uses: actions-rs/toolchain@v1
+        with:
+            toolchain: stable
+
       - name: Install latest nightly toolchain that includes Miri
         uses: actions-rs/toolchain@v1
         with:
@@ -188,11 +213,15 @@ jobs:
     - name: Checkout sources
       uses: actions/checkout@v2
 
+    - name: Install stable
+      uses: actions-rs/toolchain@v1
+      with:
+          toolchain: stable
+
     - name: Install latest nightly
       uses: actions-rs/toolchain@v1
       with:
           toolchain: nightly
-          override: true
           components: rust-src
 
     - name: Build

xtask/src/main.rs

@@ -108,13 +108,26 @@ fn run_vm_tests(opt: &QemuOpt) -> Result<()> {
 /// with VM tests, but a few things like macros and data types can be
 /// tested with regular tests.
 fn run_host_tests() -> Result<()> {
+    // Run xtask tests.
+    let cargo = Cargo {
+        action: CargoAction::Test,
+        features: Vec::new(),
+        toolchain: None,
+        packages: vec![Package::Xtask],
+        release: false,
+        target: None,
+        warnings_as_errors: false,
+    };
+    run_cmd(cargo.command()?)?;
+
+    // Run uefi-rs and uefi-macros tests.
     let cargo = Cargo {
         action: CargoAction::Test,
         features: vec![Feature::Exts],
         toolchain: Some(NIGHTLY.into()),
         // Don't test uefi-services (or the packages that depend on it)
         // as it has lang items that conflict with `std`.
-        packages: vec![Package::Uefi, Package::UefiMacros, Package::Xtask],
+        packages: vec![Package::Uefi, Package::UefiMacros],
         release: false,
         // Use the host target so that tests can run without a VM.
         target: None,