Big refactor to become more PEP8 compliant.

Mostly focused on docstrings (''' → """), indentation, empty lines,
and superfluous parenthesis.

1 files changed, 31 insertions, 29 deletions

diff --git a/rsa/prime.py b/rsa/prime.py
index 2e23a2d..4763d16 100644
--- a/rsa/prime.py
+++ b/rsa/prime.py
@@ -14,23 +14,23 @@
 #  See the License for the specific language governing permissions and
 #  limitations under the License.
 
-'''Numerical functions related to primes.
+"""Numerical functions related to primes.
 
 Implementation based on the book Algorithm Design by Michael T. Goodrich and
 Roberto Tamassia, 2002.
-'''
+"""
 
-__all__ = [ 'getprime', 'are_relatively_prime']
+__all__ = ['getprime', 'are_relatively_prime']
 
 import rsa.randnum
 
 
 def gcd(p, q):
-    '''Returns the greatest common divisor of p and q
+    """Returns the greatest common divisor of p and q
 
     >>> gcd(48, 180)
     12
-    '''
+    """
 
     while q != 0:
         (p, q) = (q, p % q)
@@ -38,11 +38,11 @@ def gcd(p, q):
 
 
 def jacobi(a, b):
-    '''Calculates the value of the Jacobi symbol (a/b) where both a and b are
+    """Calculates the value of the Jacobi symbol (a/b) where both a and b are
     positive integers, and b is odd
 
     :returns: -1, 0 or 1
-    '''
+    """
 
     assert a > 0
     assert b > 0
@@ -51,7 +51,7 @@ def jacobi(a, b):
     result = 1
     while a > 1:
         if a & 1:
-            if ((a-1)*(b-1) >> 2) & 1:
+            if ((a - 1) * (b - 1) >> 2) & 1:
                 result = -result
             a, b = b % a, a
         else:
@@ -61,10 +61,9 @@ def jacobi(a, b):
     if a == 0: return 0
     return result
 
+
 def jacobi_witness(x, n):
-    '''Returns False if n is an Euler pseudo-prime with base x, and
-    True otherwise.
-    '''
+    """Returns False if n is an Euler pseudo-prime with base x, and True otherwise."""
 
     j = jacobi(x, n) % n
 
@@ -73,13 +72,14 @@ def jacobi_witness(x, n):
     if j == f: return False
     return True
 
+
 def randomized_primality_testing(n, k):
-    '''Calculates whether n is composite (which is always correct) or
+    """Calculates whether n is composite (which is always correct) or
     prime (which is incorrect with error probability 2**-k)
 
     Returns False if the number is composite, and True if it's
     probably prime.
-    '''
+    """
 
     # 50% of Jacobi-witnesses can report compositness of non-prime numbers
 
@@ -92,24 +92,26 @@ def randomized_primality_testing(n, k):
     # this means we can use range(k) rather than range(t)
 
     for _ in range(k):
-        x = rsa.randnum.randint(n-1)
+        x = rsa.randnum.randint(n - 1)
         if jacobi_witness(x, n): return False
-    
+
     return True
 
+
 def is_prime(number):
-    '''Returns True if the number is prime, and False otherwise.
+    """Returns True if the number is prime, and False otherwise.
 
     >>> is_prime(42)
     False
     >>> is_prime(41)
     True
-    '''
+    """
 
     return randomized_primality_testing(number, 6)
 
+
 def getprime(nbits):
-    '''Returns a prime number that can be stored in 'nbits' bits.
+    """Returns a prime number that can be stored in 'nbits' bits.
 
     >>> p = getprime(128)
     >>> is_prime(p-1)
@@ -118,12 +120,11 @@ def getprime(nbits):
     True
     >>> is_prime(p+1)
     False
-    
+
     >>> from rsa import common
     >>> common.bit_size(p) == 128
     True
-    
-    '''
+    """
 
     while True:
         integer = rsa.randnum.read_random_int(nbits)
@@ -135,32 +136,33 @@ def getprime(nbits):
         if is_prime(integer):
             return integer
 
-        # Retry if not prime
+            # Retry if not prime
 
 
 def are_relatively_prime(a, b):
-    '''Returns True if a and b are relatively prime, and False if they
+    """Returns True if a and b are relatively prime, and False if they
     are not.
 
     >>> are_relatively_prime(2, 3)
     1
     >>> are_relatively_prime(2, 4)
     0
-    '''
+    """
 
     d = gcd(a, b)
-    return (d == 1)
-    
+    return d == 1
+
+
 if __name__ == '__main__':
     print('Running doctests 1000x or until failure')
     import doctest
-    
+
     for count in range(1000):
         (failures, tests) = doctest.testmod()
         if failures:
             break
-        
+
         if count and count % 100 == 0:
             print('%i times' % count)
-    
+
     print('Doctests done')