cli: skip glibc check for nixos

Fixes microsoft/vscode-remote-release#7129

Author: connor4312

cli/src/util/prereqs.rs

@@ -23,6 +23,8 @@ lazy_static! {
 	static ref MIN_LDD_VERSION: SimpleSemver = SimpleSemver::new(2, 17, 0);
 }
 
+const NIXOS_TEST_PATH: &str = "/etc/NIXOS";
+
 pub struct PreReqChecker {}
 
 impl Default for PreReqChecker {
@@ -45,13 +47,14 @@ impl PreReqChecker {
 
 	#[cfg(target_os = "linux")]
 	pub async fn verify(&self) -> Result<Platform, AnyError> {
-		let (gnu_a, gnu_b, or_musl) = tokio::join!(
+		let (is_nixos, gnu_a, gnu_b, or_musl) = tokio::join!(
+			check_is_nixos(),
 			check_glibc_version(),
 			check_glibcxx_version(),
 			check_musl_interpreter()
 		);
 
-		if gnu_a.is_ok() && gnu_b.is_ok() {
+		if (gnu_a.is_ok() && gnu_b.is_ok()) || is_nixos {
 			return Ok(if cfg!(target_arch = "x86_64") {
 				Platform::LinuxX64
 			} else if cfg!(target_arch = "armhf") {
@@ -132,6 +135,13 @@ async fn check_glibc_version() -> Result<(), String> {
 	Ok(())
 }
 
+/// Check for nixos to avoid mandating glibc versions. See:
+/// https://github.com/microsoft/vscode-remote-release/issues/7129
+#[allow(dead_code)]
+async fn check_is_nixos() -> bool {
+	fs::metadata(NIXOS_TEST_PATH).await.is_ok()
+}
+
 #[allow(dead_code)]
 async fn check_glibcxx_version() -> Result<(), String> {
 	let mut libstdc_path: Option<String> = None;