[Bug]: slither.core.expressions.new_contract.NewContract object's contract_name field is not str

[Tiko7454]

Describe the issue:

The contract name for the right expression C c = new C(); is not str

The way to get the actual contract name is to call newC.contract_name.type.name (is it the intended way?)

I think the bug is caused by the confusion between slither.core.expressions.new_contract.NewContract and slither.slithir.operations.new_contract.NewContract, both have an option contract_name but the first one is of type str, and the second is of type UserDefinedType.
I think the issue arouse in this commit

69ece6d#diff-fd01d1c9135cdceee138701706ce2947d135c9b32bf89253c5ca2f84a54979d9
new = NewContract(contract_type)

Code example to reproduce the issue:

contract C { }

contract D {
    function f() public {
        C c = new C();
    }
}

Version:

0.10.2

Relevant log output:

>>> from slither import Slither
>>> s = Slither('a.sol')
>>> d = s.contracts[1]
>>> d.name
'D'
>>> str(d.functions[0].nodes[1])
'NEW VARIABLE c = new C()'
>>> newvar = d.functions[0].nodes[1]
>>> print(newvar.expression)
c = new C()
>>> c_new_C = newvar.expression
>>> print(c_new_C.expression_right)
new C()
>>> newC = c_new_C.expression_right.called
>>> print(newC)
new C
>>> type(newC)
<class 'slither.core.expressions.new_contract.NewContract'>
>>> newC.contract_name
<slither.core.solidity_types.user_defined_type.UserDefinedType object at 0x76c1d236b310>

[0xalpharush]

This was changed purposely in #2370. It used to be a late lookup and caused issues with aliasing. In retrospect, I probably could have replaced uses of contract_name where I wanted it to be the contract and left contract_name a str

[0xalpharush]

Ah I see. I didn't update the signature of slither.core.expressions.new_contract.NewContract
https://github.com/crytic/slither/pull/2370/files#diff-fd01d1c9135cdceee138701706ce2947d135c9b32bf89253c5ca2f84a54979d9R619

[Tiko7454]

So is this newC.contract_name.type.name the intended way to get the contract name?
Also why is that called contract_name, I think it could cause further confusions and is better to be replaced with something like contract_type or contract