try to fix unit test for windows

Author: medyagh

cmd/minikube/cmd/delete.go

@@ -22,6 +22,7 @@ import (
 	"os"
 	"os/exec"
 	"path/filepath"
+	"runtime"
 	"strconv"
 	"strings"
 	"time"
@@ -655,16 +656,17 @@ func killProcess(path string) error {
 	return nil
 }
 
-// trySigKillProcess takes a PID as argument and tries to SIGKILL it.
-// It performs an ownership check of the pid,
-// before trying to send a sigkill signal to it
+// trySigKillProcess attempts to terminate a process by PID in a cross-platform way.
+// It first confirms the pid belongs to a minikube process (best-effort heuristic).
+// On Windows, if os.Process.Kill fails (common for some exited or protected processes),
+// it falls back to invoking taskkill.
 func trySigKillProcess(pid int) error {
 	itDoes, err := isMinikubeProcess(pid)
 	if err != nil {
 		return err
 	}
-
 	if !itDoes {
+		// Not a minikube process; report as stale (kept as error for existing caller semantics)
 		return fmt.Errorf("stale pid: %d", pid)
 	}
 
@@ -675,6 +677,25 @@ func trySigKillProcess(pid int) error {
 
 	klog.Infof("Killing pid %d ...", pid)
 	if err := proc.Kill(); err != nil {
+		// Benign / already gone cases (Unix & Go 1.20+)
+		lower := strings.ToLower(err.Error())
+		if errors.Is(err, os.ErrProcessDone) ||
+			strings.Contains(lower, "no such process") ||
+			strings.Contains(lower, "already finished") {
+			klog.Infof("process %d already exited", pid)
+			return nil
+		}
+
+		// Windows fallback: taskkill (handles some cases where Kill fails)
+		if runtime.GOOS == "windows" {
+			klog.Infof("os.Process.Kill failed for %d with %v - attempting taskkill", pid, err)
+			cmd := exec.Command("taskkill", "/PID", strconv.Itoa(pid), "/F", "/T")
+			if tkErr := cmd.Run(); tkErr == nil {
+				return nil
+			}
+			return errors.Wrapf(err, "failed killing pid %d (taskkill also failed)", pid)
+		}
+
 		klog.Infof("Kill failed with %v - removing probably stale pid...", err)
 		return errors.Wrapf(err, "removing likely stale unkillable pid: %d", pid)
 	}