site_file: catch for moving directory into itself

models/site_file.rb

@@ -89,6 +89,10 @@ class SiteFile < Sequel::Model
         return false, 'directory name cannot end with .htm or .html'
       end
 
+      if new_path.start_with?(current_path + '/')
+        return false, 'cannot move directory into itself'
+      end
+
     else # a file
       begin
         mime_type = Magic.guess_file_mime_type site.files_path(self.path)

tests/site_file_tests.rb

@@ -107,6 +107,20 @@ describe 'site_files' do
       _(res).must_equal [false, 'directory name cannot end with .htm or .html']
     end
 
+    it 'fails when trying to move directory into itself' do
+      @site.create_directory 'dir'
+      dir = @site.site_files_dataset.where(path: 'dir').first
+      res = dir.rename('dir/newdir')
+      _(res).must_equal [false, 'cannot move directory into itself']
+      _(@site.site_files_dataset.where(path: 'dir').first).wont_equal nil
+      _(@site.site_files_dataset.where(path: 'dir/newdir').first).must_equal nil
+
+      res = dir.rename('dir/sub/dir')
+      _(res).must_equal [false, 'cannot move directory into itself']
+      _(@site.site_files_dataset.where(path: 'dir').first).wont_equal nil
+      _(@site.site_files_dataset.where(path: 'dir/sub/dir').first).must_equal nil
+    end
+
     it 'wont set an empty directory' do
       @site.create_directory 'dirone'
       _(@site.site_files.select {|sf| sf.path == 'dirone'}.length).must_equal 1