Unit tesztek
=============

Példa
----------------------------

Készítsünk egy függvényt, amely egy másodfokú egyenlet gyökeit adja vissza! A függvény neve secondDegreeEquationSolver legyen, és kerüljön egy önálló fájlba, :file:`equationSolver.py` néven!

.. code-block:: console

  class equationSolver():

      def secondDegreeEquationSolver(self, a, b, c):
          if type(a) not in [int, float] or type(b) not in [int, float] or type(c) not in [int, float]:
              raise TypeError('Int or float only.')

          d = (b * b) - (4 * a * c)
          if d < 0:
              return None, None
          sqrtd = d ** 0.5
          return (-b + sqrtd) / 2 / a, (-b - sqrtd) / 2 / a

Készíts egy programot, mely erre a alapozva konkrét egyenletek megoldásait adja meg! A program neve legyen :file:`application.py`!

.. code-block:: console

  from equationSolver import *

  def solveTheProblem(a, b, c):
      e = equationSolver()
      x1, x2 = e.secondDegreeEquationSolver(a, b, c)  # pylint: disable=invalid-name
      print ("%dx^2 + %dx + %d = 0" % (a,b,c))
      if (x1 == None) and (x2 == None):
          print("There are no solutions.")
      if (x1 == x2):
          print("One solution has been found: %d", (x1))
      else:
          print("Two different soultions are exist: x1=%f, x2=%f" % (x1, x2))
      print("------------")

  solveTheProblem(1, 2, 8)
  solveTheProblem(1, -14, 49)
  solveTheProblem(1, 6, 8)
  solveTheProblem(1, 6, 'alma')

Készítsünk egy tesztelést végző programot :file:`test_EquationSolver.py` néven!

.. code-block:: console

  # https://docs.python.org/3/library/unittest.html
  import unittest
  from equationSolver import *


  class testEquationSolverClass(unittest.TestCase):

      @classmethod
      def setUp(self):
          print("setUp test class")
          self.tst = equationSolver()

      @classmethod
      def tearDown(self):
          print("tearDown.")

      def test_secondDegreeEquation_case_for_solutions(self):
          print("running test 1")
          self.assertEqual(self.tst.secondDegreeEquationSolver(1, 2, 8), (None, None), msg="D<0 hiba")
          print("running test 2")
          self.assertEqual(self.tst.secondDegreeEquationSolver(1, -14, 49), (7, 7), msg="D=1 hiba")
          print("running test 3")
          self.assertEqual(self.tst.secondDegreeEquationSolver(1, 6, 8), (-2, -4), msg="D=2 hiba")

      def test_secondDegreeEquation_case_TypeError(self):
          print("running TypeError test")
          with self.assertRaises(TypeError):
              result = self.tst.secondDegreeEquationSolver(True, 2, 4)


  if __name__ == '__main__':
      unittest.main()

Futtassuk:

.. code-block:: console

  koczka@columbo:~/python$ python3 test_EquationSolver.py
  setUp test class
  running TypeError test
  tearDown.
  .setUp test class
  running test 1
  running test 2
  running test 3
  tearDown.
  .
  ----------------------------------------------------------------------
  Ran 2 tests in 0.002s

  OK


Elemezzük a programot stilisztikai szempontból! Ehhez szükségünk lesz a :envvar:`pylint` modulra:

.. code-block:: console

  pip install pylint

A linter kódja:

.. code-block:: console

  import sys
  from pylint import lint
  THRESHOLD = 8

  run = lint.Run(["application.py"], do_exit=False)
  score = run.linter.stats.global_note
  # score = lint.Run(["application.py"], do_exit=False).linter.stats.global_note
  print("score=%d", score)
  if score < THRESHOLD:
      print("Linter failed: Score < threshold value")
      sys.exit(1)
  sys.exit(0)

Lássuk az elemzést!

.. code-block:: console

  koczka@columbo:~/python$ python3 lint.py
  ************* Module application
  application.py:9:0: C0325: Unnecessary parens after 'if' keyword (superfluous-parens)
  application.py:1:0: C0114: Missing module docstring (missing-module-docstring)
  application.py:1:0: W0401: Wildcard import equationSolver (wildcard-import)
  application.py:3:0: C0116: Missing function or method docstring (missing-function-docstring)
  application.py:3:0: C0103: Function name "solveTheProblem" doesn't conform to snake_case naming style (invalid-name)
  application.py:3:20: C0103: Argument name "a" doesn't conform to snake_case naming style (invalid-name)
  application.py:3:23: C0103: Argument name "b" doesn't conform to snake_case naming style (invalid-name)
  application.py:3:26: C0103: Argument name "c" doesn't conform to snake_case naming style (invalid-name)
  application.py:4:4: C0103: Variable name "e" doesn't conform to snake_case naming style (invalid-name)
  application.py:5:4: C0103: Variable name "x1" doesn't conform to snake_case naming style (invalid-name)
  application.py:5:8: C0103: Variable name "x2" doesn't conform to snake_case naming style (invalid-name)
  application.py:6:11: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
  application.py:7:8: C0121: Comparison 'x1 == None' should be 'x1 is None' (singleton-comparison)
  application.py:7:25: C0121: Comparison 'x2 == None' should be 'x2 is None' (singleton-comparison)
  application.py:12:14: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)

  ------------------------------------------------------------------
  Your code has been rated at 0.00/10 (previous run: 0.00/10, +0.00)

  score=%d 0
  Linter failed: Score < threshold value

A linter az alábbi javítások mellett éri el a 10 pontot:

.. code-block:: console


        """ Másodfokú egyenlet megoldása"""

        from equationSolver import equationSolver

        def solve_the_problem(var_a, var_b, var_c):
            """ A függvény"""
            var_e = equationSolver()
            var_x1, var_x2 = var_e.secondDegreeEquationSolver(var_a, var_b, var_c)
            print ('%dx^2 + %dx + %d = 0' % (var_a, var_b, var_c))
            if (var_x1 is None) and (var_x2 is None):
                print('Nincs megoldás')
            if var_x1==var_x2:
                print('Egy megoldás: %d', (var_x1))
            else:
                print('Két megoldás: x1=%f, x2=%f' % (var_x1, var_x2))
            print("------------")

        solve_the_problem(1, 2, 8)
        solve_the_problem(1, -14, 49)
        solve_the_problem(1, 6, 8)
        # solveTheProblem(1, 6, 'alma')

A :file:`.pylintrc` módosítja a linter működését:

.. code-block:: console

        [MASTER]

        disable=consider-using-f-string
        argument-naming-style=camelCase
        attr-naming-style=camelCase
        class-attribute-naming-style=camelCase
        class-const-naming-style=camelCase
        class-naming-style=camelCase
        const-naming-style=camelCase
        function-naming-style=camelCase
        inlinevar-naming-style=camelCase
        method-naming-style=camelCase
        module-naming-style=camelCase
        variable-naming-style=camelCase

Ezzel a program 10 pontot ér el:

.. code-block:: console

        --------------------------------------------------------------------
        Your code has been rated at 10.00/10 (previous run: 10.00/10, +0.00)

        score=%d 10.0