fix workspace output and cleanup uncertainty

tools/thothctl/internal/safeio/files_darwin_test.go

@@ -0,0 +1,44 @@
+//go:build darwin
+
+package safeio
+
+import (
+	"errors"
+	"os"
+	"path/filepath"
+	"testing"
+
+	"golang.org/x/sys/unix"
+)
+
+func TestWriteCanonicalExclusiveClassifiesUnlinkFailureAsIndeterminate(t *testing.T) {
+	root := t.TempDir()
+	stage := filepath.Join(root, "stage")
+	if err := os.WriteFile(stage, []byte("candidate"), 0o600); err != nil {
+		t.Fatal(err)
+	}
+	dir, err := unix.Open(root, unix.O_RDONLY|unix.O_DIRECTORY, 0)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer unix.Close(dir)
+	fd, err := unix.Openat(dir, "stage", unix.O_RDWR, 0)
+	if err != nil {
+		t.Fatal(err)
+	}
+	file := os.NewFile(uintptr(fd), "stage")
+	if file == nil {
+		t.Fatal("os.NewFile returned nil")
+	}
+	defer file.Close()
+	var staged unix.Stat_t
+	if err := unix.Fstat(fd, &staged); err != nil {
+		t.Fatal(err)
+	}
+	oldUnlink := darwinUnlinkat
+	t.Cleanup(func() { darwinUnlinkat = oldUnlink })
+	darwinUnlinkat = func(int, string, int) error { return errors.New("injected unlink failure") }
+	if err := cleanupDarwinStage(dir, "stage", &staged, file.Close); !errors.Is(err, ErrIndeterminateFile) {
+		t.Fatalf("unlink failure = %v, want ErrIndeterminateFile", err)
+	}
+}