bubble sort

src/listwiz/sorting.py

@@ -46,11 +46,21 @@ def merge_sort(l):
     return res
 
 
-def bubble_sort(l):
-    # We should provide bubble sort as well!
-    raise NotImplementedError
+def bubble_sort(arr):
+    n = len(arr)
+    # Traverse through all array elements
+    for i in range(n):
+        # Last i elements are already sorted
+        for j in range(0, n - i - 1):
+            # Traverse the array from 0 to n-i-1
+            # Swap if the element found is greater
+            # than the next element
+            if arr[j] > arr[j + 1]:
+                arr[j], arr[j + 1] = arr[j + 1], arr[j]
+    return arr
 
 
 def selection_sort(l):
     # We should provide selection sort.
-    raise NotImplementedError
+    raise NotImplementedError
+

tests/test_sorting.py

@@ -21,8 +21,40 @@ def test_mergesort_empty():
 
 
 def test_bubble_sort():
-    # Stub for basic bubble sort tests, see issue #9
-    pass
+    # Test even-sized list:
+    l = [3, 2, 1, 5, 4, 6]
+    res = lws.bubble_sort(l)
+    assert res == [1, 2, 3, 4, 5, 6]
+
+    # Test odd-sized list:
+    l = [5, 4, 3, 2, 1]
+    res = lws.bubble_sort(l)
+    assert res == [1, 2, 3, 4, 5]
+
+    # Test already sorted list:
+    l = [1, 2, 3, 4, 5]
+    res = lws.bubble_sort(l)
+    assert res == [1, 2, 3, 4, 5]
+
+    # Test list with duplicate elements:
+    l = [4, 2, 3, 2, 1, 3]
+    res = lws.bubble_sort(l)
+    assert res == [1, 2, 2, 3, 3, 4]
+
+    # Test list with all identical elements:
+    l = [7, 7, 7, 7]
+    res = lws.bubble_sort(l)
+    assert res == [7, 7, 7, 7]
+
+    # Test empty list:
+    l = []
+    res = lws.bubble_sort(l)
+    assert res == []
+
+    # Test single-element list:
+    l = [1]
+    res = lws.bubble_sort(l)
+    assert res == [1]
 
 
 def test_selection_sort():