crash when tring to replace None value in a list

[martinResearch]

a={}
dpath.util.new(a, ['b'], [])
dpath.util.new(a, ['b',3], 5)
dpath.util.new(a, ['b',1,"c"], 5)

creates error invalid literal for int() with base 10: 'c' lin 32 oin path.py ( result.append([path[-1], cur[int(path[-1])].class]))

[akesterson]

Can you check your code against te latest version and see if your issue is resolved?

[calebcase]

In 2.0 this happens because new will fill the first 3 array elements with None. None is a leaf so you can't add a new element under it. It is possible however to set the value to a dictionary and then proceed.

import dpath.util

a={}
print(a)

dpath.util.new(a, ['b'], [])
print(a)

dpath.util.new(a, ['b',3], 5)
print(a)

dpath.util.set(a, ['b',1], {})
print(a)

dpath.util.new(a, ['b',1,"c"], 5)
print(a)

Which outputs:

{}
{'b': []}
{'b': [None, None, None, 5]}
{'b': [None, {}, None, 5]}
{'b': [None, {'c': 5}, None, 5]}

You can avoid the situation entirely if you create lists in order.

[calebcase]

This potentially could be made more user friendly by instead filling with a sentinel value. new could then special case the sentinel and replace it as necessary with whatever is necessary (basically treating it as if it didn't exist).

[akesterson]

The 2.0 error message is significantly more comprehensible than the 1.x error message, which is a ValueError. According to the documentation, lists are created by new() up to the index given, and are filled with None, not more mappings. new() sees a string key and assumes you are trying to set a key in a mapping, and proceeds to give a list a character it can't index. ValueError results.

+1 for the sentinel value, I tried a few creative ways to do it with the functionality already in 1.0 and it was prohibitively difficult.

[akesterson]

Blocked by #136