82 lines
2.4 KiB
Plaintext
82 lines
2.4 KiB
Plaintext
This example tests the %import directive and python import from __init__.py.
|
|
|
|
This case is not correctly handled by swig 2.
|
|
|
|
The issue was reported as Source Forge bug #1297 and later as GitHub issue #7.
|
|
|
|
Use 'python runme.py' to run a test.
|
|
|
|
Overview:
|
|
---------
|
|
|
|
The example defines 2 different extension modules--each wrapping a separate C++
|
|
class.
|
|
|
|
pyX/pkg2/pkg3/foo.i - Pkg3_Foo class
|
|
pyX/pkg2/bar.i - Pkg2_Bar class derived from Pkg3_Foo
|
|
|
|
and the package pyX.pkg2 has:
|
|
|
|
pyX/pkg2/__init__.py - which imports something from "bar" module
|
|
|
|
For example with python 2.x the py2/pkg2/__init__.py imports Pkg2_Bar class as
|
|
follows
|
|
|
|
from bar import Pkg2_Bar # [1]
|
|
|
|
Such cases doesn't work when fully qualified python module names are used by
|
|
swig to generate python import directives (SF bug #1297). The generated file
|
|
"py2/pkg2/bar.py" has following lines:
|
|
|
|
import py2.pkg2.pkg3.foo # [2]
|
|
class Pkg2_Bar(py2.pkg2.pkg3.foo.Pkg3_Foo): # [3]
|
|
|
|
and it's not possible to import anything from py2.pkg2 subpackage, e.g.
|
|
|
|
import py2.pkg2
|
|
|
|
fails with the following exception:
|
|
|
|
Traceback (most recent call last):
|
|
File "runme.py", line 3, in <module>
|
|
import py2.pkg2
|
|
File "py2/pkg2/__init__.py", line 4, in <module>
|
|
from bar import Pkg2_Bar
|
|
File "py2/pkg2/bar.py", line 71, in <module>
|
|
class Pkg2_Bar(py2.pkg2.pkg3.foo.Pkg3_Foo):
|
|
AttributeError: 'module' object has no attribute 'pkg2'
|
|
|
|
It seems like during the import [1], the subpackage pkg2 is not yet fully
|
|
initialized, so pyX.pkg2 is not known. The above exception is raised at line [3].
|
|
The problem disappears, for example, if we force swig to use relative package
|
|
names.
|
|
|
|
The difference between this ('from_init2') case and the case
|
|
'from_init1' is that here it's not sufficient to import relative module
|
|
by just ignoring the package part of the fully qualified module name. IOW
|
|
it is not correct to force swig to put:
|
|
|
|
import foo
|
|
class Pkg2_Bar(foo.Pkg3_Foo)
|
|
|
|
into pyX/pkg2/bar.py (note, that this would work for 'from_init1' case).
|
|
The import directive shall be rather:
|
|
|
|
import pkg3.foo
|
|
|
|
for python 2.x and:
|
|
|
|
from . import pkg3
|
|
import pkg3.foo
|
|
|
|
for python 3, and the class definition shall begin with:
|
|
|
|
class Pkg2_Bar(pkg3.foo.Pkg3_Foo)
|
|
|
|
If everything works well, the package pyX.pkg2 shall load properly.
|
|
|
|
Unix:
|
|
-----
|
|
- Run make
|
|
- Run the test as described above
|