add class SelectionSort.py and test_selection_sort.py

Author: Diegoslourenco

classical_algorithms/python/SelectionSort.py

@@ -0,0 +1,17 @@
+class SelectionSort:
+    def sort(self, array):
+        if array is None:
+            raise TypeError('array cannot be None')
+        return self._sort(array)
+
+    def _sort(self, array):
+        if len(array) < 2:
+            return array
+
+        for i in range(len(array)):
+            minimum = i
+            for j in range(i+1, len(array)):
+                if array[j] < array[i]:
+                    array[i], array[j] = array[j], array[i]
+
+        return array

classical_algorithms/python/tests/test_selection_sort.py

@@ -0,0 +1,28 @@
+import unittest
+from classical_algorithms.python.SelectionSort import SelectionSort
+
+class TestSelectionSort(unittest.TestCase):
+    def test_selection_sort(self):
+        selection_sort = SelectionSort()
+
+        print('None Input')
+        self.assertRaises(TypeError, selection_sort.sort, None)
+
+        print('Empty Input')
+        self.assertEqual(selection_sort.sort([]), [])
+
+        print('One Element')
+        self.assertEqual(selection_sort.sort([25]), [25])
+
+        print('Two or More Elements')
+        array = [10, 1, 0, 100, 5, 15, 100, 7]
+        self.assertEqual(selection_sort.sort(array), sorted(array))
+
+        print('Two or More with negative Elements')
+        array = [10, -1, 0, 100, 5, 15, -100, -7]
+        self.assertEqual(selection_sort.sort(array), sorted(array))
+
+        print('Success: selection_sort_sort\n')
+
+if __name__ == '__main__':
+    unittest.main()