[Sqlalchemy-tickets] Issue #4261: TypeError while using sqlalchemy.Enum with enum.Enum (zzzeek/sqlalchemy)

[Piotr P. <iss...@bi...>]

New issue 4261: TypeError while using sqlalchemy.Enum with enum.Enum
https://bitbucket.org/zzzeek/sqlalchemy/issues/4261/typeerror-while-using-sqlalchemyenum-with

Piotr Pokorski:

Hi!

I'm working on a database, where some of the columns need to have an enumeration/dictionary attribute, so I decided to use a sqlalchemy.Enum type like described in the [doc](http://docs.sqlalchemy.org/en/latest/core/type_basics.html#sqlalchemy.types.Enum). Here is an example showing the problem:

```
#!python

import enum
import sqlalchemy as db
from sqlalchemy.ext.declarative import declarative_base

Base = declarative_base()

class Sizes(enum.Enum):
    SMALL = 0
    MEDIUM = 1
    LARGE = 2

class Test(Base):
    __tablename__ = 'Test'
    size = db.Column(db.Enum(Sizes), nullable=False)
 
engine = db.create_engine('sqlite:///test.db')
Base.metadata.create_all(engine)
```

which throws:

```
#!python

Traceback (most recent call last):
  File "C:/Users/User/PycharmProjects/project/test.py", line 15, in <module>
    class Test(Base):
  File "C:/Users/User/PycharmProjects/project/test.py", line 18, in Test
    size = db.Column(db.Enum(Sizes), nullable=False)
  File "C:\Python27\lib\site-packages\sqlalchemy\sql\sqltypes.py", line 1296, in __init__
    self._enum_init(enums, kw)
  File "C:\Python27\lib\site-packages\sqlalchemy\sql\sqltypes.py", line 1332, in _enum_init
    length = max(len(x) for x in self.enums)
  File "C:\Python27\lib\site-packages\sqlalchemy\sql\sqltypes.py", line 1332, in <genexpr>
    length = max(len(x) for x in self.enums)
TypeError: object of type 'type' has no len()
```
Setup information:

```
#!python
Python 2.7.15 (v2.7.15:ca079a3ea3, Apr 30 2018, 16:30:26) [MSC v.1500 64 bit (AMD64)] on win32
sqlalchemy.__version__
'1.2.7'

```

Thank you for your help!