chore: ci

src-tauri/tests/common/mod.rs

@@ -1,6 +1,22 @@
 use std::path::PathBuf;
 use std::process::Command;
 
+/// Whether Docker can run the Linux images these fixtures are built from.
+///
+/// `docker version` succeeding is not enough: the Windows CI runner ships a
+/// daemon in Windows-container mode, which answers that command happily and
+/// then rejects the fixtures with `unknown capability: "CAP_NET_ADMIN"`.
+#[allow(dead_code)]
+pub fn docker_supports_linux_containers() -> bool {
+  Command::new("docker")
+    .args(["version", "--format", "{{.Server.Os}}"])
+    .output()
+    .map(|output| {
+      output.status.success() && String::from_utf8_lossy(&output.stdout).trim() == "linux"
+    })
+    .unwrap_or(false)
+}
+
 /// Utility functions for integration tests
 pub struct TestUtils;
 

src-tauri/tests/donut_proxy_integration.rs

@@ -1612,10 +1612,8 @@ async fn test_local_proxy_with_shadowsocks_upstream(
   let binary_path = setup_test().await?;
   let mut tracker = ProxyTestTracker::new(binary_path.clone());
 
-  // Check Docker availability
-  let docker_check = std::process::Command::new("docker").arg("version").output();
-  if docker_check.map(|o| !o.status.success()).unwrap_or(true) {
-    eprintln!("skipping Shadowsocks e2e test because Docker is unavailable");
+  if !common::docker_supports_linux_containers() {
+    eprintln!("skipping Shadowsocks e2e test because Docker cannot run Linux containers");
     return Ok(());
   }
 

src-tauri/tests/test_harness/mod.rs

@@ -24,13 +24,9 @@ fn has_external_wireguard_service() -> bool {
   std::env::var("VPN_TEST_WG_HOST").is_ok()
 }
 
-/// Check if Docker is available
+/// Check if Docker can run the Linux fixtures this harness needs
 pub fn is_docker_available() -> bool {
-  Command::new("docker")
-    .arg("version")
-    .output()
-    .map(|o| o.status.success())
-    .unwrap_or(false)
+  crate::common::docker_supports_linux_containers()
 }
 
 /// Start a WireGuard test server and return client config

src-tauri/tests/vpn_integration.rs

@@ -775,7 +775,7 @@ async fn test_wireguard_traffic_flows_through_donut_proxy(
 
   cleanup_runtime().await;
   if !test_harness::is_docker_available() {
-    eprintln!("skipping WireGuard e2e test because Docker is unavailable");
+    eprintln!("skipping WireGuard e2e test because Docker cannot run Linux containers");
     return Ok(());
   }