//go:build !linux && !darwin && !windows

package fileops

import (
	"errors"
	"os"
	"path/filepath"
	"strings"
	"testing"
)

func TestPromoteDirectoryFailsBeforeCreatingTemporaryTree(t *testing.T) {
	root := t.TempDir()
	src := filepath.Join(root, "source")
	dst := filepath.Join(root, "destination")
	if err := os.Mkdir(src, 0o755); err != nil {
		t.Fatalf("Mkdir(source) error = %v", err)
	}
	if err := os.WriteFile(filepath.Join(src, "value.txt"), []byte("source"), 0o644); err != nil {
		t.Fatalf("WriteFile(source) error = %v", err)
	}

	err := PromoteDirectory(src, dst)
	if !errors.Is(err, ErrAtomicDirectoryPromotionUnsupported) {
		t.Fatalf("PromoteDirectory() error = %v, want unsupported capability", err)
	}
	entries, readErr := os.ReadDir(root)
	if readErr != nil {
		t.Fatalf("ReadDir(root) error = %v", readErr)
	}
	for _, entry := range entries {
		if entry.Name() == filepath.Base(dst) || strings.HasPrefix(entry.Name(), ".destination.tmp-") {
			t.Fatalf("unsupported promotion created %q", entry.Name())
		}
	}
}