Why can't I use lists and dicts as arguments in a search custom function? Is that by design or a bug? Example code included.

[tgkuus]

In the read the docs section Advanced queries>Custom test with parameters:
I noticed I can't have the arguments in the test function be lists or dicts. Is that by design or a bug?

Example of the issue. Note that the first error is at line 30. After the code is the error traceback I got.

from tinydb import TinyDB, Query

def test_function(val,arg1,arg2):
    if '0' == list(val.keys())[0]:
        return True
    else:
        return False
#make the db and add some data
x = TinyDB('questions.json')
x.truncate() #reset for testing
some_fake_data = [{'data':{xidx:xval}} for xidx,xval in enumerate(reversed(range(100)))]
print('1\n\t',some_fake_data)
x.insert_multiple(some_fake_data)
print('2\n\t',x.all())

#search normal - WORKS!
the_return = x.search(Query().data == {'0': 99})
print('3\n\t',the_return)

#search normal with test function args int and string - WORKS!
arg1=0
arg2='asd'
q=Query()
the_return = x.search(q.data.test(test_function,arg1,arg2))
print('4\n\t',the_return)

#search normal with test function args list and int - DOES NOT WORK
arg1=[0,1,2,3]
arg2=1
the_return = x.search(q.data.test(test_function,arg1,arg2))
print('5\n\t',the_return)

#search normal with test function args int and dict - DOES NOT WORK
arg1=1
arg2={'asd':1}
the_return = x.search(q.data.test(test_function,arg1,arg2))
print('6\n\t',the_return)

'''
Error Recieved
Traceback (most recent call last):
  File "...", line 31, in <module>
    the_return = x.search(q.data.test(test_function,arg1,arg2))
  File "...", line 245, in search
    cached_results = self._query_cache.get(cond)
  File "...", line 91, in get
    value = self.cache.get(key)
  File "...", line 98, in __hash__
    return hash(self._hash)
TypeError: unhashable type: 'dict'
'''

[msiemens]

Hey, seems like TinyDB doesn't work properly in the case you described, I'll open an issue for this 🙂

[tgkuus]

Thanks!