fix(ci): remove the nightly_toolchain feature gate for assert_matches

CONTRIBUTING.md

@@ -108,10 +108,6 @@ The following tools should be installed as a part of the `windows-drivers-rs` de
 
 The crates in this repository are designed to work with `stable` rust. Some of the crates expose a `nightly` feature that adds additional functionality that requires unstable rust features in the `nightly` toolchains.
 
-#### In `test` targets and unit tests
-
-`test` targets and unit tests in other targets will automatically enable nightly features when a nightly toolchain is detected. This is done via the `nightly_toolchain` `cfg` value. This allows us to take advantage of unstable features (ex. [`assert_matches`](https://doc.rust-lang.org/std/assert_matches/macro.assert_matches.html)) in tests.
-
 ### Build and Test
 
 To **only build** the workspace: `cargo build --locked --all-features`

crates/wdk-build/build.rs

@@ -1,21 +1,24 @@
 // Copyright (c) Microsoft Corporation
 // License: MIT OR Apache-2.0
 
-//! Build script for the `wdk-build` crate
+//! Build script for the `wdk-build` crate.
 //!
-//! This provides a `nightly_toolchain` feature to the `wdk-build` crate, so
-//! that it can conditionally enable unstable features.
+//! This provides a temporary fix for using `assert_matches!` in specific Rust
+//! versions in the `wdk-build` crate.
 
 fn main() {
-    println!("cargo::rustc-check-cfg=cfg(nightly_toolchain)");
-    setup_nightly_cfgs();
+    println!("cargo::rustc-check-cfg=cfg(assert_matches_stabilized)");
+    setup_assert_matches_stabilized_cfg();
 }
 
-// Custom attributes cannot be applied to expressions yet, so separate functions are required for nightly/non-nightly: https://github.com/rust-lang/rust/issues/15701
-#[rustversion::nightly]
-fn setup_nightly_cfgs() {
-    println!("cargo::rustc-cfg=nightly_toolchain");
+// Custom attributes cannot be applied to expressions yet, so separate functions
+// are required for `rustversion` conditional compilation: https://github.com/rust-lang/rust/issues/15701
+// TODO: Remove the `setup_assert_matches_stabilized_cfg` feature and related
+// code once the minimum supported Rust version is 1.95.0 or later.
+#[rustversion::since(1.95.0)]
+fn setup_assert_matches_stabilized_cfg() {
+    println!("cargo::rustc-cfg=assert_matches_stabilized");
 }
 
-#[rustversion::not(nightly)]
-const fn setup_nightly_cfgs() {}
+#[rustversion::before(1.95.0)]
+const fn setup_assert_matches_stabilized_cfg() {}

crates/wdk-build/src/lib.rs

@@ -10,7 +10,6 @@
 //! includes being ables to select different WDF versions and different driver
 //! models (WDM, KMDF, UMDF).
 
-#![cfg_attr(nightly_toolchain, feature(assert_matches))]
 use std::{
     env,
     fmt,
@@ -1547,7 +1546,7 @@ pub fn detect_wdk_build_number() -> Result<u32, ConfigError> {
 
 #[cfg(test)]
 mod tests {
-    #[cfg(nightly_toolchain)]
+    #[cfg(assert_matches_stabilized)]
     use std::assert_matches;
     use std::{collections::HashMap, ffi::OsStr, sync::Mutex};
 
@@ -1824,7 +1823,7 @@ mod tests {
     fn default_config() {
         let config = with_env(&[("CARGO_CFG_TARGET_ARCH", Some("x86_64"))], Config::new);
 
-        #[cfg(nightly_toolchain)]
+        #[cfg(assert_matches_stabilized)]
         assert_matches!(config.driver_config, DriverConfig::Wdm);
         assert_eq!(config.cpu_architecture, CpuArchitecture::Amd64);
     }
@@ -1836,7 +1835,7 @@ mod tests {
             ..Config::default()
         });
 
-        #[cfg(nightly_toolchain)]
+        #[cfg(assert_matches_stabilized)]
         assert_matches!(config.driver_config, DriverConfig::Wdm);
         assert_eq!(config.cpu_architecture, CpuArchitecture::Amd64);
     }
@@ -1848,7 +1847,7 @@ mod tests {
             ..Config::default()
         });
 
-        #[cfg(nightly_toolchain)]
+        #[cfg(assert_matches_stabilized)]
         assert_matches!(
             config.driver_config,
             DriverConfig::Kmdf(KmdfConfig {
@@ -1871,7 +1870,7 @@ mod tests {
             ..Config::default()
         });
 
-        #[cfg(nightly_toolchain)]
+        #[cfg(assert_matches_stabilized)]
         assert_matches!(
             config.driver_config,
             DriverConfig::Kmdf(KmdfConfig {
@@ -1890,7 +1889,7 @@ mod tests {
             ..Config::default()
         });
 
-        #[cfg(nightly_toolchain)]
+        #[cfg(assert_matches_stabilized)]
         assert_matches!(
             config.driver_config,
             DriverConfig::Umdf(UmdfConfig {
@@ -1913,7 +1912,7 @@ mod tests {
             ..Config::default()
         });
 
-        #[cfg(nightly_toolchain)]
+        #[cfg(assert_matches_stabilized)]
         assert_matches!(
             config.driver_config,
             DriverConfig::Umdf(UmdfConfig {
@@ -2082,7 +2081,7 @@ mod tests {
                 Config::validate_and_add_folder_path(&mut include_paths, non_existent_path);
 
             assert!(result.is_err());
-            #[cfg(nightly_toolchain)]
+            #[cfg(assert_matches_stabilized)]
             assert_matches!(
                 result.unwrap_err(),
                 ConfigError::DirectoryNotFound { directory } if directory == non_existent_path.to_string_lossy()
@@ -2100,7 +2099,7 @@ mod tests {
             let result = Config::validate_and_add_folder_path(&mut include_paths, file.path());
 
             assert!(result.is_err());
-            #[cfg(nightly_toolchain)]
+            #[cfg(assert_matches_stabilized)]
             assert_matches!(
                 result.unwrap_err(),
                 ConfigError::DirectoryNotFound { directory } if directory == file.path().to_string_lossy()