new: tests

Author: Maxim Kochukov

.travis.yml

@@ -0,0 +1,11 @@
+language: python
+python:
+  - "3.3"
+  - "3.4"
+  - "3.5"
+  - "3.6"
+  - "3.7"
+install:
+  - pip install -r requirements.txt
+script:
+  - pytest

README.md

@@ -6,7 +6,9 @@
 ![PyPI - Python Version](https://img.shields.io/pypi/pyversions/randcrack.svg)
 ![PyPI - Implementation](https://img.shields.io/pypi/implementation/randcrack.svg)
 
-This script is able to predict python's `random` module random generated values. Script was tested against **Python 3.5.2**, **3.6.2.** and **3.7.0.** Should work against other versions of Python as well, since the generator is pretty much the same in **2.7.12**. Enjoy!
+This script is able to predict python's `random` module random generated values.
+
+Script was tested against **Python 3.5.2**, **3.6.2.** and **3.7.0.** Should work against other versions of Python as well, since the generator is pretty much the same in **2.7.12**. Enjoy!
 
 ## Installation
 To install randcrack, simply:

randcrack/randcrack.py

@@ -7,8 +7,8 @@ def __init__(self):
 
     def submit(self, num):
         if self.state:
-            print("Already got enough bits")
-            return
+            raise ValueError("Already got enough bits")
+
         bits = self._to_bitarray(num)
 
         assert (all([x == 0 or x == 1 for x in bits]))
@@ -20,8 +20,8 @@ def submit(self, num):
 
     def _predict_32(self):
         if not self.state:
-            print("Didn't recieve enough bits to predict")
-            return 0
+            raise ValueError("Didn't recieve enough bits to predict")
+
         if self.counter >= 624:
             self._regen()
         self.counter += 1
@@ -30,8 +30,8 @@ def _predict_32(self):
 
     def predict_getrandbits(self, k):
         if not self.state:
-            print("Didn't recieve enough bits to predict")
-            return 0
+            raise ValueError("Didn't recieve enough bits to predict")
+
         if k == 0:
             return 0
         words = (k - 1) // 32 + 1
@@ -208,7 +208,8 @@ def _regen(self):
 
 
 if __name__ == "__main__":
-    import random, time
+    import random
+    import time
 
     print("Testing random module cracker...")
 

tests/test_randcrack.py

@@ -0,0 +1,52 @@
+import random
+import time
+
+import pytest
+
+from randcrack import RandCrack
+
+
+def test_submit_not_enough():
+    random.seed(time.time())
+
+    cracker = RandCrack()
+
+    for i in range(623):
+        cracker.submit(random.randint(0, 4294967294))
+
+    with pytest.raises(ValueError):
+        cracker.predict_randint(0, 1)
+
+
+def test_submit_too_much():
+    random.seed(time.time())
+
+    cracker = RandCrack()
+
+    for i in range(624):
+        cracker.submit(random.randint(0, 4294967294))
+
+    with pytest.raises(ValueError):
+        cracker.submit(random.randint(0, 4294967294))
+
+
+def test_predict_first_624():
+    random.seed(time.time())
+
+    cracker = RandCrack()
+
+    for i in range(624):
+        cracker.submit(random.randint(0, 4294967294))
+
+    assert sum([random.getrandbits(32) == cracker.predict_getrandbits(32) for _ in range(1000)]) >= 620
+
+
+def test_predict_first_1000_close():
+    random.seed(time.time())
+
+    cracker = RandCrack()
+
+    for i in range(624):
+        cracker.submit(random.randint(0, 4294967294))
+
+    assert sum([random.getrandbits(32) == cracker.predict_getrandbits(32) for _ in range(1000)]) >= 980