From efb642880de0384ef4234968989f1dd609b46ecb Mon Sep 17 00:00:00 2001
From: Christian Clauss <cclauss@me.com>
Date: Fri, 16 Apr 2021 14:45:36 +0200
Subject: [PATCH] Add Python doctests to binary search (#193)

* Add Python doctests to binary search

* Add Python doctests to binary search

* Rename searching/python/binary-search.py to algorithms/Python/searching/binary-search.py

* Rename binary-search.py to binary_search.py
---
 algorithms/Python/searching/binary_search.py | 29 ++++++++++++++++----
 1 file changed, 24 insertions(+), 5 deletions(-)

diff --git a/algorithms/Python/searching/binary_search.py b/algorithms/Python/searching/binary_search.py
index 6e15a22f..b8f8ee19 100644
--- a/algorithms/Python/searching/binary_search.py
+++ b/algorithms/Python/searching/binary_search.py
@@ -1,10 +1,26 @@
+from collections import namedtuple
+
+TestData = namedtuple("TestData", "array target expected")
+
+test_data = (
+    TestData([1, 2, 3, 4, 5], 1, True),
+    TestData([0, 4, 10, 1000], 10, True),
+    TestData([], -2, False),
+)
+
+
 def binary_search(array: list, target: int) -> bool:
-    """ searches through a sorted list to find a target integer """
-    mid = len(array) // 2
+    """
+    Search a sorted list to find a target integer
+
+    >>> all(binary_search(x.array, x.target) == x.expected for x in test_data)
+    True
+    """
     if len(array) < 1:
         return False
     if len(array) == 1:
         return array[0] == target
+    mid = len(array) // 2
     if array[mid] < target:
         return binary_search(array[mid:], target)
     elif array[mid] > target:
@@ -12,7 +28,10 @@ def binary_search(array: list, target: int) -> bool:
     else:
         return True
 
+
 if __name__ == "__main__":
-    print(binary_search([1, 2, 3, 4, 5], 1))
-    print(binary_search([0, 4, 10, 1000], 10))
-    print(binary_search([], -2))
+    for item in test_data:
+        print(
+            f"binary_search({item.array}, {item.target}) is "
+            f"{binary_search(item.array, item.target)}"
+        )