from dataclasses import dataclass from pathlib import PurePath from typing import Set @dataclass class MarkDuplicateException(Exception): """ Tried to mark a file that was already marked. """ path: PurePath @dataclass class MarkConflictException(Exception): """ Marking the path would have caused a conflict. A conflict can have two reasons: Either the new file has the same path as the parent directory of a known file, or a parent directory of the new file has the same path as a known file. In either case, adding the new file would require a file and a directory to share the same path, which is usually not possible. """ path: PurePath collides_with: PurePath class Report: """ A report of a synchronization. Includes all files found by the crawler, as well as the set of changes made to local files. """ def __init__(self) -> None: self.known_files: Set[PurePath] = set() self.new_files: Set[PurePath] = set() self.changed_files: Set[PurePath] = set() self.deleted_files: Set[PurePath] = set() def mark(self, path: PurePath) -> None: """ Mark a previously unknown file as known. May throw a MarkDuplicateException or a MarkConflictException. For more detail, see the respective exception's docstring. """ for known_path in self.known_files: if path == known_path: raise MarkDuplicateException(path) if path.relative_to(known_path) or known_path.relative_to(path): raise MarkConflictException(path, known_path) self.known_files.add(path) def marked(self, path: PurePath) -> bool: return path in self.known_files def add_file(self, path: PurePath) -> None: """ Unlike mark(), this function accepts any paths. """ self.new_files.add(path) def change_file(self, path: PurePath) -> None: """ Unlike mark(), this function accepts any paths. """ self.changed_files.add(path) def delete_file(self, path: PurePath) -> None: """ Unlike mark(), this function accepts any paths. """ self.deleted_files.add(path)