jython-dev

[Jython-dev] two (more) bugs (?)

[Samuele P. <pe...@in...>]

Hi.

Let's consider the following module/pkg/dir hierarchy:
TOP/
 a.py
 p0/
  __init__.py
  x.py
  y.py
  p1/
  __init__.py
  z.py
  
all python files just contain:
print __name__

except a.py:

import p0.x

print __name__

and x.py:

import y
import p1.z

print __name__

(0) If one executes a.py from TOP with CPython 1.5/1.6/2.0 everything
 works fine.
 
(1) Jython instead fails to locate p1 relative to x package (stmt import p1.z in 
x.py).

Built-in Package Support in Python 1.5 
( http://www.python.org/doc/essays/packages.html )

is not explicit about loading packages relative to modules in pkgs, it only
speaks about module (but pkgs "are" modules) rel. import, in any case CPython 
behaviour is to find p1 package relative to x package p0 completing import p1.z 
in x.py.
So jython seems buggy in this respect.
Notice that jython correctly locate y.

(2) If one compiles a.py with jythonc and the --deep option,
p0.y will not be compiled. The relative import rule is ignored
by jythonc. In my opinion this is a bug, and I know how possibly
fix this.

Both bugs are better solved in the "grand" *loading cleanup...

(a little note) Differently from jython, jythonc follows
the proposed precedence py > java. For the rest (java loading)
it uses the org.python.core runtime. Is that true?
 

Remarks are welcome.

regards, Samuele

Re: [Jython-dev] two (more) bugs (?)

[<bc...@wo...>]

[Samuele]

>Let's consider the following module/pkg/dir hierarchy:
>TOP/
> a.py
> p0/
>  __init__.py
>  x.py
>  y.py
>  p1/
>  __init__.py
>  z.py
>  
>all python files just contain:
>print __name__
>
>except a.py:
>
>import p0.x
>
>print __name__
>
>and x.py:
>
>import y
>import p1.z
>
>print __name__
>
>(0) If one executes a.py from TOP with CPython 1.5/1.6/2.0 everything
> works fine.
> 
>(1) Jython instead fails to locate p1 relative to x package (stmt import p1.z in 
>x.py).
>
>Built-in Package Support in Python 1.5 
>( http://www.python.org/doc/essays/packages.html )
>
>is not explicit about loading packages relative to modules in pkgs, it only
>speaks about module (but pkgs "are" modules) rel. import, in any case CPython 
>behaviour is to find p1 package relative to x package p0 completing import p1.z 
>in x.py.
>So jython seems buggy in this respect.

I agree, this is bug. Complex python applications depends on this
relative behaviour, so it should be fixed. OTOH, since no one have
reported the bug it does not have get a high priority.

(Once on python-dev, it was suggested that relative imports should look
in each package, the whole way up the package structure. If my memory
serves me right, there was a very high level of agreement that this
would be a good thing)

>Notice that jython correctly locate y.
>
>(2) If one compiles a.py with jythonc and the --deep option,
>p0.y will not be compiled. The relative import rule is ignored
>by jythonc. In my opinion this is a bug, and I know how possibly
>fix this.

Also a bug IMO. Also a low priority for the same reasons.

>Both bugs are better solved in the "grand" *loading cleanup...
>
>(a little note) Differently from jython, jythonc follows
>the proposed precedence py > java. For the rest (java loading)
>it uses the org.python.core runtime. Is that true?

I don't think so. jythonc creates a list of known java packages and
passes this list on to sys.add_package() during initialization. This
creates PyJavaPackages which is currently searched before the python
modules. I think. But hey, you're the expert <wink>.

regards,
finn