Convert git-check-ref-format logic into a single regexp

darcs-to-git

@@ -287,26 +287,16 @@ class DarcsPatch
     self.name = patch_xml.get_elements('name').first.get_text.value.darcs_unescape rescue 'Unnamed patch'
     self.comment = patch_xml.get_elements('comment').first.get_text.value.darcs_unescape rescue nil
     if (self.is_tag = (self.name =~ /^TAG (.*)/))
-      self.git_tag_name = $1.gsub(/[\s:*]+/, '_')
-      # git tag names cannot start or end with a period
-      if (self.git_tag_name[0] == ?.)
-        self.git_tag_name[0] = ?_
-      end
-      if (self.git_tag_name[self.git_tag_name.length - 1] == ?.)
-        self.git_tag_name[self.git_tag_name.length - 1] = ?_
-      end
-      # git tag names cannot contain two successive periods
-      while (i = self.git_tag_name.index('..'))
-        self.git_tag_name[i + 1] = ?_
-      end
-      # git tag names cannot contain #{
-      while (i = self.git_tag_name.index('#{'))
-        self.git_tag_name[i + 1] = ?_
-      end
+      self.git_tag_name = self.safe_patch_name($1)
     end
     @git_author_name, @git_author_email = AUTHOR_MAP[author]
   end
 
+  def safe_patch_name(darcs_name)
+    # See 'man git-check-ref-format'
+    darcs_name.gsub(/(?:[\s:*]+|\.{2,}|\#\{|^.|\.$)/, '_')
+  end
+
   def <=>(other)
     self.identifier <=> other.identifier
   end