Enhance sentinel_linear_search doctests with edge cases and type variations

Author: JesunAhmadUshno

searches/sentinel_linear_search.py

@@ -14,10 +14,17 @@
 def sentinel_linear_search(sequence, target):
     """Pure implementation of sentinel linear search algorithm in Python
 
-    :param sequence: some sequence with comparable items
+    :param sequence: a mutable list with comparable items. Note: this function
+        temporarily mutates the input list by appending and then removing the
+        target value, but the list is restored to its original state.
     :param target: item value to search
     :return: index of found item or None if item is not found
 
+    The sentinel linear search algorithm works by appending the target value to the
+    end of the list before searching. This eliminates the need for boundary checking
+    during the loop, as the search is guaranteed to find the target (at minimum, at
+    the end where the sentinel is placed). The input list is restored after the search.
+
     Examples:
     >>> sentinel_linear_search([0, 5, 7, 10, 15], 0)
     0
@@ -30,6 +37,35 @@ def sentinel_linear_search(sequence, target):
 
     >>> sentinel_linear_search([0, 5, 7, 10, 15], 6)
 
+    >>> sentinel_linear_search([1], 1)
+    0
+
+    >>> sentinel_linear_search([1], 99)
+
+    >>> sentinel_linear_search([], 5)
+
+    >>> sentinel_linear_search([3, 1, 4, 1, 5, 9, 2, 6], 9)
+    5
+
+    >>> sentinel_linear_search([3, 1, 4, 1, 5, 9, 2, 6], 1)
+    1
+
+    >>> sentinel_linear_search(['a', 'b', 'c', 'd'], 'c')
+    2
+
+    >>> sentinel_linear_search(['a', 'b', 'c', 'd'], 'z')
+
+    >>> sentinel_linear_search([1.5, 2.7, 3.14, 4.0], 3.14)
+    2
+
+    >>> sentinel_linear_search([1.5, 2.7, 3.14, 4.0], 2.5)
+
+    >>> sentinel_linear_search([-10, -5, 0, 5, 10], -5)
+    1
+
+    >>> sentinel_linear_search([-10, -5, 0, 5, 10], 0)
+    2
+
     """
     sequence.append(target)