bottles_test.py

import pytest
from bottles import CountdownSong, BottleVerse


def responds_to_lyrics(role_player):
  return hasattr(role_player, 'lyrics') and callable(role_player.lyrics)


class TestBottleVerse:
  def test_plays_verse_role(self):
    assert responds_to_lyrics(BottleVerse)

  def test_verse_general_rule_upper_bound(self):
    expected = (
      '99 bottles of beer on the wall, '
      '99 bottles of beer.\n'
      'Take one down and pass it around, '
      '98 bottles of beer on the wall.\n'
    )
    assert BottleVerse.lyrics(99) == expected

  def test_verse_general_rule_lower_bound(self):
    expected = (
      '3 bottles of beer on the wall, '
      '3 bottles of beer.\n'
      'Take one down and pass it around, '
      '2 bottles of beer on the wall.\n'
    )
    assert BottleVerse.lyrics(3) == expected

  def test_verse_7(self):
    expected = (
      '7 bottles of beer on the wall, '
      '7 bottles of beer.\n'
      'Take one down and pass it around, '
      '1 six-pack of beer on the wall.\n'
    )
    assert BottleVerse.lyrics(7) == expected

  def test_verse_6(self):
    expected = (
      '1 six-pack of beer on the wall, '
      '1 six-pack of beer.\n'
      'Take one down and pass it around, '
      '5 bottles of beer on the wall.\n'
    )
    assert BottleVerse.lyrics(6) == expected

  def test_verse_2(self):
    expected = (
      '2 bottles of beer on the wall, '
      '2 bottles of beer.\n'
      'Take one down and pass it around, '
      '1 bottle of beer on the wall.\n'
    )
    assert BottleVerse.lyrics(2) == expected

  def test_verse_1(self):
    expected = (
      '1 bottle of beer on the wall, '
      '1 bottle of beer.\n'
      'Take it down and pass it around, '
      'no more bottles of beer on the wall.\n'
    )
    assert BottleVerse.lyrics(1) == expected

  def test_verse_0(self):
    expected = (
      'No more bottles of beer on the wall, '
      'no more bottles of beer.\n'
      'Go to the store and buy some more, '
      '99 bottles of beer on the wall.\n'
    )
    assert BottleVerse.lyrics(0) == expected


class VerseFake:
  @staticmethod
  def lyrics(number):
    return f'This is verse {number}.\n'


class TestVerseFake:
  def test_plays_verse_role(self):
    assert responds_to_lyrics(VerseFake)


class TestCountdownSong:
  def test_verse(self):
    expected = 'This is verse 500.\n'
    assert CountdownSong(verse_template=VerseFake).verse(500) == expected

  def test_verses(self):
    expected = (
      'This is verse 99.\n'
      '\n'
      'This is verse 98.\n'
      '\n'
      'This is verse 97.\n'
    )
    assert CountdownSong(verse_template=VerseFake).verses(99, 97) == expected

  def test_song(self):
    expected = (
      'This is verse 47.\n'
      '\n'
      'This is verse 46.\n'
      '\n'
      'This is verse 45.\n'
      '\n'
      'This is verse 44.\n'
      '\n'
      'This is verse 43.\n'
    )
    assert CountdownSong(verse_template=VerseFake, max=47, min=43).song() == expected