pacman.py

# @ -> our hero
# G -> ghosts
# P -> pills
# . -> empty spaces
# | and - -> walls
map = [
    "|--------|",
    "|G..|..G.|",
    "|...PP...|",
    "|G...@.|.|",
    "|........|",
    "|--------|"
]

def find_pacman(map):
    pacman_x = -1
    pacman_y = -1

    for x in range(len(map)):
        for y in range(len(map[x])):
            if map[x][y] == '@':
                pacman_x = x
                pacman_y = y

    return pacman_x, pacman_y

def move_pacman(map, next_pacman_x, next_pacman_y):
    pacman_x, pacman_y = find_pacman(map)

    # the place where the pacman was is now empty
    everything_to_the_left = map[pacman_x][0:pacman_y]
    everything_to_the_right = map[pacman_x][pacman_y+1:]
    map[pacman_x] = everything_to_the_left + "." + everything_to_the_right

    # the new place has the pacman
    everything_to_the_left = map[next_pacman_x][0:next_pacman_y]
    everything_to_the_right = map[next_pacman_x][next_pacman_y+1:]
    map[next_pacman_x] = everything_to_the_left + "@" + everything_to_the_right

pacman_tests.py

import unittest

from pacman import find_pacman, move_pacman


class PacmanTest(unittest.TestCase):

    def test_find_pacman(self):
        map = [
            "|--------|",
            "|G..|..G.|",
            "|...PP...|",
            "|G...@.|.|",
            "|........|",
            "|--------|"
        ]

        x, y = find_pacman(map)

        self.assertEqual(x, 3)
        self.assertEqual(y, 5)

    def test_find_pacman_when_pacman_doesnt_exist(self):
        map = [
            "|--------|",
            "|G..|..G.|",
            "|...PP...|",
            "|G.....|.|",
            "|........|",
            "|--------|"
        ]

        x, y = find_pacman(map)

        self.assertEqual(x, -1)
        self.assertEqual(y, -1)

    def test_move_pacman(self):
        map = [
            "|--------|",
            "|G..|..G.|",
            "|...PP...|",
            "|G...@.|.|",
            "|........|",
            "|--------|"
        ]

        move_pacman(map, 4, 1)

        new_x, new_y = find_pacman(map)

        self.assertEqual(new_x, 4)
        self.assertEqual(new_y, 1)