`test_run_with_check_raise` fails on OpenIndiana

[mtelka]

The test_run_with_check_raise test fails on OpenIndiana with this error:

__________________________ test_run_with_check_raise ___________________________

    def test_run_with_check_raise() -> None:
        """Asure compatibility with subprocess.run when using check (return 1)."""
        with pytest.raises(subprocess.CalledProcessError) as ours:
            run("false", check=True)
        with pytest.raises(subprocess.CalledProcessError) as original:
            subprocess.run("false", check=True, universal_newlines=True)
>       assert ours.value.returncode == original.value.returncode
E       AssertionError: assert 1 == 255
E        +  where 1 = CalledProcessError(1, 'false').returncode
E        +    where CalledProcessError(1, 'false') = <ExceptionInfo CalledProcessError(1, 'false') tblen=2>.value
E        +  and   255 = CalledProcessError(255, 'false').returncode
E        +    where CalledProcessError(255, 'false') = <ExceptionInfo CalledProcessError(255, 'false') tblen=2>.value

test/test_unit.py:114: AssertionError

On OpenIndiana there are two false commands:

$ /usr/bin/false ; echo $?
255
$ /usr/gnu/bin/false ; echo $?
1
$

When the test is run the PATH environment variable contains /usr/bin before /usr/gnu/bin, but the user's default is the opposite. This means that run() (ours) honors current PATH, but subprocess.run() (original) does not.