1. 在代码中直接写doctest测试用例。
测试用例使用“>>>”，应输出结果就直接换行，不使用“>>>”。如果测试结果和应输出结果相同，则通过测试。用例的位置一是模块的开头，或者是函数声明语句的下一行（本文给的例子就这种情况）。其中注意下应输出的结果一定要严格匹配，比如“hello”和'hello'就是不同的输出。
# doctest_practice.py
def add_two_positive_number(a,b):
"""
>>> add_two_positive_number(2,3)
5
>>> add_two_positive_number(100,200)
300
"""
assert a > 0 and b> 0, "both needs to be positive"
return a+b
add_two_positive_number(1,3)
#add_two_positive_number(-1,4) # AssertionError
# using python -o assert-and-testing.py will ignore all the assertion code!!
def double(values):
""" double the values in a list
>>> double([1,2,3,4])
[2, 4, 6, 8]
>>> double([])
[]
>>> double(['a', 'b', 'c'])
['aa', 'bb', 'cc']
>>> double([True, None])
Traceback (most recent call last):
...
TypeError: unsupported operand type(s) for *: 'int' and 'NoneType'
"""
return [2 * element for element in values]
# doctest expect all str to have single str not double str
def say_hi():
"""
>>> say_hi()
'hi'
"""
return "hi"
# Watch out for whitespace!
# (There's a trailing space on line 42)
def true_that():
"""
>>> true_that()
True
"""
return True
# Order of keys in dicts matters in doctests
def make_dict(keys):
"""
>>> make_dict(['a','b'])
{'a': True, 'b': True}
"""
return {key: True for key in keys}
测试时候直接用以下命令：
python3 -m doctest -v doctest_practice.py
测试结果由于是verbose所以会比较详细：
Trying:
add_two_positive_number(2,3)
Expecting:
5
ok
Trying:
add_two_positive_number(100,200)
Expecting:
300
ok
Trying:
double([1,2,3,4])
Expecting:
[2, 4, 6, 8]
ok
Trying:
double([])
Expecting:
[]
ok
Trying:
double(['a', 'b', 'c'])
Expecting:
['aa', 'bb', 'cc']
ok
Trying:
double([True, None])
Expecting:
Traceback (most recent call last):
...
TypeError: unsupported operand type(s) for *: 'int' and 'NoneType'
ok
Trying:
make_dict(['a','b'])
Expecting:
{'a': True, 'b': True}
ok
Trying:
say_hi()
Expecting:
'hi'
ok
Trying:
true_that()
Expecting:
True
ok
1 items had no tests:
doctest_practice
5 items passed all tests:
2 tests in doctest_practice.add_two_positive_number
4 tests in doctest_practice.double
1 tests in doctest_practice.make_dict
1 tests in doctest_practice.say_hi
1 tests in doctest_practice.true_that
9 tests in 6 items.
9 passed and 0 failed.
Test passed.
2. doctest测试用例单独放在一个文件里面
我这里就把其中一个用例放在了doctest_practice_testfile.txt里面：
>>> from doctest_practice import double
>>> double([1,2,3,4])
[2, 4, 6, 8]
注意一下这个里面的from ... import... 也需要用“>>>”。测试的时候就直接输入以下命令就好了：
python3 -m doctest -v doctest_practice_testfile.txt
测试执行结果：
Trying:
from doctest_practice import double
Expecting nothing
ok
Trying:
double([1,2,3,4])
Expecting:
[2, 4, 6, 8]
ok
1 items passed all tests:
2 tests in doctest_practice_testfile.txt
2 tests in 1 items.
2 passed and 0 failed.
Test passed.
