| """Utilities for working with paths.""" | |
| from collections.abc import Sequence | |
| from contextlib import suppress | |
| def normalize_path_segments(segments: Sequence[str]) -> list[str]: | |
| """Drop '.' and '..' from a sequence of str segments""" | |
| resolved_path: list[str] = [] | |
| for seg in segments: | |
| if seg == "..": | |
| # ignore any .. segments that would otherwise cause an | |
| # IndexError when popped from resolved_path if | |
| # resolving for rfc3986 | |
| with suppress(IndexError): | |
| resolved_path.pop() | |
| elif seg != ".": | |
| resolved_path.append(seg) | |
| if segments and segments[-1] in (".", ".."): | |
| # do some post-processing here. | |
| # if the last segment was a relative dir, | |
| # then we need to append the trailing '/' | |
| resolved_path.append("") | |
| return resolved_path | |
| def normalize_path(path: str) -> str: | |
| # Drop '.' and '..' from str path | |
| prefix = "" | |
| if path and path[0] == "/": | |
| # preserve the "/" root element of absolute paths, copying it to the | |
| # normalised output as per sections 5.2.4 and 6.2.2.3 of rfc3986. | |
| prefix = "/" | |
| path = path[1:] | |
| segments = path.split("/") | |
| return prefix + "/".join(normalize_path_segments(segments)) | |