fix: harden thothctl Windows safe I/O

tools/thothctl/cmd/thothctl/main_test.go

@@ -3,14 +3,14 @@ package main
 import (
 	"bytes"
 	"context"
-	"errors"
 	"fmt"
 	"os"
 	"path/filepath"
-	"runtime"
 	"strconv"
 	"strings"
 	"testing"
+
+	"github.com/aritmolab/thothii/tools/thothctl/internal/testsupport"
 )
 
 func TestRunLogsRedactsAnUnlabelledDeclaredSecret(t *testing.T) {
@@ -155,7 +155,7 @@ func TestRunFailsClosedForTraversalAndParentSymlinkSecretSources(t *testing.T) {
 				t.Fatal(err)
 			}
 			linkDirectory := filepath.Join(fixture.root, "linked")
-			symlinkOrSkip(t, realDirectory, linkDirectory)
+			testsupport.SymlinkOrSkip(t, realDirectory, linkDirectory)
 			return filepath.Join(linkDirectory, "secret")
 		},
 		"final symlink": func(t *testing.T, fixture cliFixture) string {
@@ -164,7 +164,7 @@ func TestRunFailsClosedForTraversalAndParentSymlinkSecretSources(t *testing.T) {
 				t.Fatal(err)
 			}
 			linkSecret := filepath.Join(fixture.root, "linked-secret")
-			symlinkOrSkip(t, realSecret, linkSecret)
+			testsupport.SymlinkOrSkip(t, realSecret, linkSecret)
 			return linkSecret
 		},
 	} {
@@ -458,13 +458,3 @@ func assertDockerNotInvoked(t *testing.T, fixture cliFixture) {
 		t.Errorf("Docker was invoked: stat error = %v", err)
 	}
 }
-
-func symlinkOrSkip(t *testing.T, target, link string) {
-	t.Helper()
-	if err := os.Symlink(target, link); err != nil {
-		if runtime.GOOS == "windows" && errors.Is(err, os.ErrPermission) {
-			t.Skip("Windows symlink privilege is unavailable")
-		}
-		t.Fatal(err)
-	}
-}