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Misleading __reduce_cython__ error on import
See original GitHub issueWhenever you use an import instead of a cimport compiling will work but you might be graced with an unrelated error message at import time.
Can’t create easily a self-contained test: I tried and the code was failing with an expected ImportError, however you can reproduce it it with:
git clone git@github.com:psycopg/psycopg3.git mypyerr
cd mypyerr
git checkout 5647fb04dc6eb3e46e2a7bde490feea5be11f2c1
cat <<HERE | patch -p1
--- a/psycopg3/types/text.pyx
+++ b/psycopg3/types/text.pyx
@@ -1,3 +1,4 @@
+from cpython.unicode import PyUnicode_DecodeAscii
from cpython.unicode cimport PyUnicode_DecodeUTF8
cdef object load_text_binary(const char *data, size_t length, void *context):
HERE
python setup.py develop
python -c "import psycopg3._psycopg3"
Which raises the error:
Traceback (most recent call last):
File "<string>", line 1, in <module>
File "psycopg3/pq/pq_cython.pyx", line 34, in init psycopg3._psycopg3
cdef class PGconn:
AttributeError: type object 'psycopg3._psycopg3.PGconn' has no attribute '__reduce_cython__'
I believe many help requests about __reduce_cython__ are related to this.
Tested with Python 3.6 and Cython 3.0a1.
Issue Analytics
- State:
- Created 3 years ago
- Reactions:1
- Comments:12 (6 by maintainers)
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@scoder Move the exception before the class definition and it does break in master though. I’ve edited the example above
Confirmed fixed for my use case too. Thank you for working on it even if my test wasn’t easy to reproduce! 👍