test: close remaining workspace preprocessing gates

tools/thothctl/internal/compose/process_windows_test.go

@@ -3,9 +3,15 @@
 package compose
 
 import (
-	"golang.org/x/sys/windows"
+	"context"
+	"errors"
+	"os"
 	"os/exec"
+	"path/filepath"
 	"testing"
+	"time"
+
+	"golang.org/x/sys/windows"
 )
 
 func TestOwnedProcessUsesCreationTimeJobAttribute(t *testing.T) {
@@ -24,3 +30,74 @@ func TestOwnedJobPolicyKillsDescendantsOnClose(t *testing.T) {
 		t.Fatal("owned job must use kill-on-close policy")
 	}
 }
+
+// TestWindowsProcessHelper is both a test helper and the child process used by the runtime
+// ownership regression below. The child writes a marker only if it outlives its parent job.
+func TestWindowsProcessHelper(t *testing.T) {
+	mode := os.Getenv("THOTHCTL_WINDOWS_HELPER")
+	if mode == "" {
+		return
+	}
+	marker := os.Getenv("THOTHCTL_WINDOWS_MARKER")
+	if mode == "child" {
+		time.Sleep(2 * time.Second)
+		_ = os.WriteFile(marker, []byte("survived"), 0o600)
+		return
+	}
+	child := exec.Command(os.Args[0], "-test.run=TestWindowsProcessHelper", "--")
+	child.Env = append(os.Environ(), "THOTHCTL_WINDOWS_HELPER=child", "THOTHCTL_WINDOWS_MARKER="+marker)
+	if err := child.Start(); err != nil {
+		t.Fatal(err)
+	}
+	if mode == "exit" {
+		return
+	}
+	if mode == "cancel" {
+		for {
+			time.Sleep(time.Second)
+		}
+	}
+	for {
+		_, _ = os.Stdout.Write([]byte("overflow\n"))
+		time.Sleep(time.Millisecond)
+	}
+}
+
+func TestOwnedProcessTerminatesDescendantOnOverflowCancelAndParentExit(t *testing.T) {
+	for _, mode := range []string{"overflow", "cancel", "exit"} {
+		t.Run(mode, func(t *testing.T) {
+			marker := filepath.Join(t.TempDir(), "descendant-marker")
+			t.Setenv("THOTHCTL_WINDOWS_HELPER", mode)
+			t.Setenv("THOTHCTL_WINDOWS_MARKER", marker)
+			ctx := context.Background()
+			var cancel context.CancelFunc
+			if mode == "cancel" {
+				ctx, cancel = context.WithCancel(ctx)
+			}
+			result := make(chan error, 1)
+			go func() {
+				_, err := runBoundedWindows(ctx, os.Args[0], []string{"-test.run=TestWindowsProcessHelper", "--"}, nil, CaptureLimits{StdoutBytes: 1024, StderrBytes: 1024})
+				result <- err
+			}()
+			if mode == "cancel" {
+				time.Sleep(100 * time.Millisecond)
+				cancel()
+			}
+			select {
+			case err := <-result:
+				if mode == "overflow" && !errors.Is(err, ErrOutputLimit) {
+					t.Fatalf("overflow error = %v, want ErrOutputLimit", err)
+				}
+				if mode == "cancel" && !errors.Is(err, context.Canceled) {
+					t.Fatalf("cancel error = %v, want context.Canceled", err)
+				}
+			case <-time.After(5 * time.Second):
+				t.Fatal("owned process did not terminate")
+			}
+			time.Sleep(150 * time.Millisecond)
+			if _, err := os.Stat(marker); !errors.Is(err, os.ErrNotExist) {
+				t.Fatalf("descendant marker error = %v; descendant survived %s termination", err, mode)
+			}
+		})
+	}
+}