"""
Implementa Fibonacci.
"""

def fib(n):
    """Fibonacci:
    Se n <= 1, fib(n) = 1
    Se n > 1, fib(n) = fib(n - 1) + fib(n - 2)
    
    Exemplos de uso:
    
    >>> fib(0)
    1
    >>> fib(1)
    1
    >>> fib(10)
    100
    >>> [ fib(x) for x in xrange(10) ]
    [1, 1, 2, 3, 5, 8, 13, 21, 34, 55]
    >>> fib('')
    Traceback (most recent call last):
      File "<input>", line 1, in ?
      File "<input>", line 19, in fib
    TypeError
    >>> 
    """
    if not type(n) is int:
        raise TypeError

    if n > 1:
        return fib(n - 1) + fib(n - 2)
    else:
        return 1

def _doctest():
    """
    Evoca o doctest.
    """

    import doctest
    doctest.run_docstring_examples(fib, globals())

if __name__ == "__main__":

    _doctest()

"""

Usa unittest para testar fib.py.
"""

import fib
import unittest

class TestSequenceFunctions(unittest.TestCase):

    def setUp(self):
        self.seq = range(10)

    def test0(self):
        self.assertEqual(fib.fib(0), 1)

    def test1(self):
        self.assertEqual(fib.fib(1), 1)

    def test10(self):
        self.assertEqual(fib.fib(10), 89)

    def testseq(self):
        fibs = [1, 1, 2, 3, 5, 8, 13, 21, 34, 55]
        
        for x, y in zip(fibs, [ fib.fib(x) for x in self.seq ]):
            self.assert_(x is y)

    def testtype(self):
        self.assertRaises(TypeError, fib.fib, '')

if __name__ == '__main__':
    
    suite = unittest.TestLoader().loadTestsFromTestCase(TestSequenceFunctions)
    unittest.TextTestRunner(verbosity=2).run(suite)