Coverage for src/rhiza_hooks/_toml.py: 100%

1#!/usr/bin/env python3 

2"""Shared lenient TOML loader. 

3 

4Every hook that reads a TOML file — ``pyproject.toml``, ``Cargo.toml``, 

5``rust-toolchain.toml``, ``.bumpversion.toml`` — treats a missing, malformed or 

6unreadable file as "unspecified": a broken manifest is somebody else's error to 

7report, not a reason to crash the commit. That stance used to be implemented 

8separately in five modules, whose ``except`` tuples drifted apart until two of 

9them crashed on invalid UTF-8 (#396). This module is now the only place that 

10calls :func:`tomllib.load`. 

11""" 

12 

13from __future__ import annotations 

14 

15import tomllib 

16from pathlib import Path 

17from typing import Any 

18 

19 

20def load_toml(path: Path) -> dict[str, Any] | None: 

21 """Parse a TOML file, treating unreadable or malformed input as absent. 

22 

23 Args: 

24 path: File to parse. 

25 

26 Returns: 

27 The parsed mapping, or None if the file is missing, malformed, not valid 

28 UTF-8, or cannot be opened (for example, the path is a directory). 

29 """ 

30 if not path.exists(): 

31 return None 

32 try: 

33 with path.open("rb") as handle: 

34 return tomllib.load(handle) 

35 except (tomllib.TOMLDecodeError, OSError, UnicodeDecodeError): 

36 # tomllib decodes the stream itself, so invalid UTF-8 surfaces as 

37 # UnicodeDecodeError rather than a TOML error. Anything else (e.g. a 

38 # genuine bug) is left to surface. 

39 return None