Doctest for nested docstring

Question

Suppose I have following code:

def foo(s):
    """A dummy function foo. For example:

>>> a = '''This is a test string line 1
This is a test string line 2
This is a test string line 3'''
>>> foo(a)
This is a test string line 1
This is a test string line 2
This is a test string line 3
>>>
    """
    print s

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

And let's save it as foo.py. When I run:

C:\Python27>python.exe foo.py
**********************************************************************
File "foo.py", line 5, in __main__.foo
Failed example:
    a = '''This is a test string line 1
Exception raised:
    Traceback (most recent call last):
      File "C:\Python27\lib\doctest.py", line 1254, in __run
        compileflags, 1) in test.globs
      File "<doctest __main__.foo[0]>", line 1
        a = '''This is a test string line 1
                                          ^
    SyntaxError: EOF while scanning triple-quoted string literal
**********************************************************************
File "foo.py", line 8, in __main__.foo
Failed example:
    foo(a)
Exception raised:
    Traceback (most recent call last):
      File "C:\Python27\lib\doctest.py", line 1254, in __run
        compileflags, 1) in test.globs
      File "<doctest __main__.foo[1]>", line 1, in <module>
        foo(a)
    NameError: name 'a' is not defined
**********************************************************************
1 items had failures:
   2 of   2 in __main__.foo
***Test Failed*** 2 failures.

Have tried indent the docstring ( >>> a = '''...'''. Have checked all indents - 4 spaces for each indent) and changed single quote to double quote (>>> a = """...."""), the errors are different and the doctest just won't go successfully. Currently the only thing work is to join all lines to a extreme long string and separate with '\r\n'.

Do I miss something?

Answer 1

I think you need to put some dots there

>>> a = """This is a test string line 1
... This is a test string line 2
... This is a test string line 3"""