Coverage for lobster/common/graphviz_utils.py: 88%

1#!/usr/bin/env python3 

2# 

3# LOBSTER - Lightweight Open BMW Software Traceability Evidence Report 

4# Copyright (C) 2025 Bayerische Motoren Werke Aktiengesellschaft (BMW AG) 

5# 

6# This program is free software: you can redistribute it and/or modify 

7# it under the terms of the GNU Affero General Public License as 

8# published by the Free Software Foundation, either version 3 of the 

9# License, or (at your option) any later version. 

10# 

11# This program is distributed in the hope that it will be useful, but 

12# WITHOUT ANY WARRANTY; without even the implied warranty of 

13# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 

14# Affero General Public License for more details. 

15# 

16# You should have received a copy of the GNU Affero General Public 

17# License along with this program. If not, see 

18# <https://www.gnu.org/licenses/>. 

19"""Shared Graphviz utilities for LOBSTER report tools.""" 

20 

21import subprocess 

22from typing import Optional 

23 

24 

25def is_dot_available(dot: Optional[str] = None) -> bool: 

26 """Return True if the ``dot`` executable (Graphviz) is on PATH. 

27 

28 Args: 

29 dot: Optional explicit path to the ``dot`` binary. When ``None`` 

30 (default) the system PATH is searched. 

31 

32 Returns: 

33 ``True`` if Graphviz ``dot`` is available, ``False`` otherwise. 

34 """ 

35 try: 

36 subprocess.run( 

37 [dot if dot else "dot", "-V"], 

38 stdout=subprocess.PIPE, 

39 stderr=subprocess.PIPE, 

40 encoding="UTF-8", 

41 check=True, 

42 timeout=5, 

43 ) 

44 return True 

45 except (FileNotFoundError, subprocess.TimeoutExpired, 

46 subprocess.CalledProcessError): 

47 return False