Case-sensitivity problem

[kirill-bessonov]

cocotb==1.6.2
cocotbext-axi==0.1.16
Questa Sim-64 Version 10.7f

Hello,

I published this problem in cocotbext-axi: alexforencich/cocotbext-axi#40
But I've tracked it to the Bus class.
My SystemVerilog Interface's instance contains all signals from AXI4-Stream spec (all uppercase as in spec), i.e.
TDATA,
TLAST,
TKEEP,
TUSER,
TVALID,
TREADY
Let's launch remote_pdb and see at Bus constructor in cocotb_bus/bus.py file. (I'll omit line's numbers because they shifted because of "breakpoints")
See in this loop "for attr_name, sig_name in _build_sig_attr_dict(optional_signals).items():" where "optional signals" must be founded.
Here are some Pdb logs:

---

(Pdb) p dir(entity)
['ACLK', 'ARESETn', 'TDATA', 'TID', 'TKEEP', 'TLAST', 'TREADY', 'TUSER', 'TVALID', '_HierarchyObject__get_sub_handle_by_name', 'class', 'delattr', 'dict', 'dir', 'doc', 'eq', 'format', 'ge', 'getattr', 'getattribute', 'gt', 'hash', 'init', 'init_subclass', 'iter', 'le', 'len', 'lt', 'module', 'ne', 'new', 'reduce', 'reduce_ex', 'repr', 'setattr', 'sizeof', 'str', 'subclasshook', 'weakref', '_child_path', '_compat_mapping', '_def_file', '_def_name', '_discover_all', '_discovered', '_fullname', '_handle', '_id', '_invalid_sub_handles', '_len', '_log', '_name', '_path', '_sub_handle_key', '_sub_handles', '_type', 'get_definition_file', 'get_definition_name']
(Pdb) p signame
'tvalid'
(Pdb) !hasattr(entity, signame)
False
(Pdb) !hasattr(entity,'tvalid')
False
(Pdb) !hasattr(entity,'TVALID')
True

---

Comparing to previous loop which finds "main" signals, this has hasattr() function which checks if "optional signal" is exist. And it's case-sensitive. So this is where "case-sensitivity" option loses its functionality.

[kirill-bessonov]

I've added to the Bus class following method:

---

def _caseInsensHasattr(self, obj, attr):
    for a in dir(obj):
        if a.casefold() == attr.casefold():
            return hasattr(obj, a)

---

then in line 72 I've replaced "if hasattr(entity, signame):" to "if self._caseInsensHasattr(entity, signame):"
and everything seems to work as it should be.

[alexforencich]

Presumably this was fixed with b4196ba