issue on internal import in a package

[人言落日是天涯，望极天涯不见家]

On Feb 27, 9:22 pm, "Frank Millman" <fr... at chagford.com> wrote:
> "Ben Finney" <ben+pyt... at benfinney.id.au> wrote in message
>
> news:87ei6t646h.fsf at benfinney.id.au...
>
>
>
> > 人言落日是天涯，望极天涯不见家 <kelvin.... at gmail.com> writes:
>
> >> Here is a simple example:
> >> [app]
> >>       [module]
> >>             __init__.py   --> empty
> >>             a.py   --> import b
> >>             b.py  --> defined a function foo()
> >>       test.py
>
> >> In the test.py, contains the below statement:
> >> from module import a
> >> Execute the test.py will get error:
>
> > This works fine for me::
>
> >    $ mkdir --parents app/module/
> >    $ touch app/module/__init__.py
> >    $ printf "import b\n" > app/module/a.py
> >    $ printf "def foo(): pass\n" > app/module/b.py
> >    $ printf "from module import a\n" > app/test.py
> >    $ find .
> >    .
> >    ./app
> >    ./app/module
> >    ./app/module/__init__.py
> >    ./app/module/a.py
> >    ./app/module/b.py
> >    ./app/test.py
>
> >    $ python app/test.py
>
> >> Traceback (most recent call last):
> >>   File "<stdin>", line 1, in <module>
> >>   File "module\a.py", line 1, in <module>
> >>     import b
> >> ImportError: No module named b
>
> >> Why the b.py can not be found by a.py?
>
> > I get no errors; the code appears to run fine. Perhaps the scenario is
> > not exactly as you describe?
>
> I get exactly the same result as the OP, using python 3.2 on both windows
> and linux. It works using python 2.6.
>
> I can fix it by changing a.py from 'import b' to 'from . import b'.
>
> As I understand it, the reason is that python 3.x will no longer look for an
> absolute import in the current package - it will only look in sys.path.
>
> Frank Millman

This behavior is by design or just a bug for Python3.x ?