Fix/inlet outlet connections

[schmoelder]

With this PR, an exception is raised whenever a user tries to connect an Outlet unit operation to another unit, or some unit to an Inlet unit operation.

@hannahlanzrath @daklauss Do we already handle this in #95?

Fixes #139

Todo

• Raise Exceptions
• Add tests

[hannahlanzrath]

AFAIK this is not explicitly caught, but inexplicitly via "CADETProcessError: Origin/Destination unit does not support ports."

[schmoelder]

Thanks. Would you be up for adding some tests to this branch here?

[hannahlanzrath]

Will do 👍

[daklauss]

I wrote a small test on #95 and we actually do not caugh the exception. It actually errors out by subscripting over non existant dict entrys, in the connections dict. So yeah we still have to catch this error.

import unittest

from CADETProcess import CADETProcessError
from CADETProcess.processModel import ComponentSystem
from CADETProcess.processModel import Inlet, Outlet, Cstr
from CADETProcess.processModel import FlowSheet
from CADETProcess.processModel import Process

class Test_inlet_outlet(unittest.TestCase):
    
    def test_io(self):
        comp_sys = ComponentSystem(1)

        flow_sheet = FlowSheet(comp_sys)

        inlet = Inlet(comp_sys, "inlet")
        outlet = Outlet(comp_sys, "outlet")
        cstr = Cstr(comp_sys, "cstr")


        flow_sheet.add_unit(inlet)
        flow_sheet.add_unit(outlet)
        flow_sheet.add_unit(cstr)

        self.assertRaises(RuntimeError,flow_sheet.add_connection(outlet, cstr))

        self.assertRaises(RuntimeError,flow_sheet.add_connection(cstr, inlet))

        self.assertRaises(RuntimeError,flow_sheet.add_connection(outlet, inlet))`

./test_io.py::Test_inlet_outlet::test_io Failed with Error: 'NoneType' object is not subscriptable
  File "C:\Users\klauss\AppData\Local\miniconda3\envs\cadsem\Lib\unittest\case.py", line 57, in testPartExecutor
    yield
  File "C:\Users\klauss\AppData\Local\miniconda3\envs\cadsem\Lib\unittest\case.py", line 623, in run
    self._callTestMethod(testMethod)
  File "C:\Users\klauss\AppData\Local\miniconda3\envs\cadsem\Lib\unittest\case.py", line 579, in _callTestMethod
    if method() is not None:
       ^^^^^^^^
  File "c:\Users\klauss\Documents\Arbeitsprojekte\ModSim\Ports\CADET-Process\tests\test_io.py", line 25, in test_io
    self.assertRaises(RuntimeError,flow_sheet.add_connection(outlet, cstr))
                                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "c:\Users\klauss\Documents\Arbeitsprojekte\ModSim\Ports\CADET-Process\CADETProcess\processModel\flowSheet.py", line 99, in wrapper
    return func(self, origin, destination, *args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "c:\Users\klauss\Documents\Arbeitsprojekte\ModSim\Ports\CADET-Process\CADETProcess\processModel\flowSheet.py", line 129, in wrapper
    results = func(self, *args, **kwargs)
              ^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "c:\Users\klauss\Documents\Arbeitsprojekte\ModSim\Ports\CADET-Process\CADETProcess\processModel\flowSheet.py", line 445, in add_connection
    if destination_port in self._connections[origin]['destinations'][origin_port][destination]:
                           ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^
TypeError: 'NoneType' object is not subscriptable```

[hannahlanzrath]

We will sort it out. This week didn't work out unfortunately but next week @daklauss and I will do an intense cadet-process + ports session.

[daklauss]

Wrote some tests for checking errorraising of wrong inlet/outlet connections. Additionaly added tests for the other cases in which add_connection raises errors. The "connection already exists" case may already be covered in test_name_decorator, but the others are not.