doctest

• Última modificación: Mayo 14, 2022

%%writefile example.py
"""
This is the "example" module.

The example module supplies one function, factorial().  For example,

>>> factorial(5)
120
"""

def factorial(n):
    """Return the factorial of n, an exact integer >= 0.

    >>> [factorial(n) for n in range(6)]
    [1, 1, 2, 6, 24, 120]
    >>> factorial(30)
    265252859812191058636308480000000
    >>> factorial(-1)
    Traceback (most recent call last):
        ...
    ValueError: n must be >= 0

    Factorials of floats are OK, but the float must be an exact integer:
    >>> factorial(30.1)
    Traceback (most recent call last):
        ...
    ValueError: n must be exact integer
    >>> factorial(30.0)
    265252859812191058636308480000000

    It must also not be ridiculously large:
    >>> factorial(1e100)
    Traceback (most recent call last):
        ...
    OverflowError: n too large
    """

    import math
    if not n >= 0:
        raise ValueError("n must be >= 0")
    if math.floor(n) != n:
        raise ValueError("n must be exact integer")
    if n+1 == n:  # catch a value like 1e300
        raise OverflowError("n too large")
    result = 1
    factor = 2
    while factor <= n:
        result *= factor
        factor += 1
    return result


if __name__ == "__main__":
    import doctest
    doctest.testmod()

Overwriting example.py

#
# Ejecución
#
!python3 example.py

#
# verbose
#
!python3 example.py -v

Trying:
    factorial(5)
Expecting:
    120
ok
Trying:
    [factorial(n) for n in range(6)]
Expecting:
    [1, 1, 2, 6, 24, 120]
ok
Trying:
    factorial(30)
Expecting:
    265252859812191058636308480000000
ok
Trying:
    factorial(-1)
Expecting:
    Traceback (most recent call last):
        ...
    ValueError: n must be >= 0
ok
Trying:
    factorial(30.1)
Expecting:
    Traceback (most recent call last):
        ...
    ValueError: n must be exact integer
ok
Trying:
    factorial(30.0)
Expecting:
    265252859812191058636308480000000
ok
Trying:
    factorial(1e100)
Expecting:
    Traceback (most recent call last):
        ...
    OverflowError: n too large
ok
2 items passed all tests:
   1 tests in __main__
   6 tests in __main__.factorial
7 tests in 2 items.
7 passed and 0 failed.
Test passed.

Verificación de ejemplos en Docstrings

Llamado a DocTest dentro del código

if __name__ == "__main__":
    import doctest
    doctest.testmod()

Llamado a DocTest por fuera del código

$ python3 -m doctest -v example.py

Verificación de ejemplos en un archivo de texto

%%writefile example.txt
The ``example`` module
======================

Using ``factorial``
-------------------

This is an example text file in reStructuredText format.  First import
``factorial`` from the ``example`` module:

    >>> from example import factorial

Now use it:

    >>> factorial(6)
    120

Overwriting example.txt

%%writefile test.py
import doctest

doctest.testfile("./example.txt")

Overwriting test.py

!python3 test.py

**********************************************************************
File "./example.txt", line 14, in example.txt
Failed example:
    factorial(6)
Expected:
    120
Got:
    720
**********************************************************************
1 items had failures:
   1 of   2 in example.txt
***Test Failed*** 1 failures.

!python3 -m doctest -v example.txt

Trying:
    from example import factorial
Expecting nothing
ok
Trying:
    factorial(6)
Expecting:
    120
**********************************************************************
File "example.txt", line 14, in example.txt
Failed example:
    factorial(6)
Expected:
    120
Got:
    720
**********************************************************************
1 items had failures:
   1 of   2 in example.txt
2 tests in 1 items.
1 passed and 1 failed.
***Test Failed*** 1 failures.