cmdx.listRelatives always returns None

[vonbehr]

Steps to reproduce:

1. Create cube primitive.
2. run
   `import cmdx
   import maya.cmds as cmds

print cmdx.listRelatives("pCube1")
print cmds.listRelatives("pCube1")`

cmds.listRelatives returns [u'pCubeShape1'] while
cmdx.listRelatives("pCube1") returns None

Example from the command reference also returns false and not true.

cmdx 0.4.6
Maya 2020.2
Windows 10

[mottosso]

Thanks for reporting this @fvbehr, are you able to spot what's going on?

[vonbehr]

No, I am afraid that debugging this is beyond my skill level.

[mottosso]

For the time being, you can do:

list(cmdx.encode("pCube1").descendents())

For hierarchy, or any of the other options here.

[mottosso]

Could it be that for cmds.listRelatives the shapes=True argument defaults to True? If you pass shapes=True does it return values as you expect? It's False here in cmdx, apparently. It should act like Maya's cmdx.listRelatives however, so if this is the case then that's a bug.

[vonbehr]

Testsetup:

• group1
  |__ pCube1

cmdx.listRelatives("pCube1") returns None
cmds.listRelatives("pCube1") returns [u'pCubeShape1']

cmdx.listRelatives("pCube1", shapes=True) returns None
cmds.listRelatives("pCube1", shapes=True) returns [u'pCubeShape1']

cmdx.listRelatives("pCube1", shapes=False) returns None
cmds.listRelatives("pCube1", shapes=False) returns [u'pCubeShape1']

cmdx.listRelatives("group1", shapes=True) returns None
cmds.listRelatives("group1", shapes=True) returns None

cmdx.listRelatives("group1") returns None
cmds.listRelatives("group1") returns [u'pCube1']

cmdx.listRelatives("group1", allDescendents=True) returns None
cmds.listRelatives("group1", allDescendents=True) returns [u'pCubeShape1', u'pCube1']

It looks like cmdx always returns None. No mater what flags are used.

[vonbehr]

Could it be that for cmds.listRelatives the shapes=True argument defaults to True?

The shapes=True flag only returns shape nodes. It defaults to False and then returns all nodes, including shapes.

[mottosso]

I think I see the problem.

• cmdx/cmdx.py

  Line 4250 in d2203e8

  if not isinstance(node, DagNode):

It's expecting a cmdx.DagNode whereas we are passing a string. Yes, I think we should either add support for automatically converting strings to cmdx objects, or you can..

cmdx.listRelatives(cmdx.encode("pCube1"))

Normally, all commands from cmdx return cmdx objects, like cmdx.createNode and even cmdx.listRelatives. But it's true, it would be convenient to mimic Maya's cmds more closely here. If so, it would be a matter of adding this to listRelatives.

if isinstance(node, str):
  node = encode(node)

That would handle the conversion automatically and internally. What do you think?

[vonbehr]

I would prefer if it would mimic Maya's cmds.

I added the if statement to listRelatives.

cmdx.listRelatives("pCube1") returns None while
cmdx.listRelatives("pCube1", shapes=True) returns [|group1|pCube1|pCubeShape1], the whole hierarchy
cmdx.listRelatives("pCube1", children=True) returns [ ] and
cmdx.listRelatives("group1", children=True) returns [|group1|pCube1]

So its not returning the same as cmds.

What values can I pass as the type argument? It expects an int. All values except 0 seem to return an empty list.

[mottosso]

It's expecting an cmdx type, like cmdx.kJoint. It's one of these, alternatively from the Maya API directly for more choice, here e.g. om.MFn.kJoint.

The reason for not taking a string like cmds is performance.

returns [|group1|pCube1|pCubeShape1], the whole hierarchy

It's actually returning a cmdx.DagNode which when you print it calls node.path(). Nodes in cmdx are absolute references that doesn't break when they move or change name. Try calling node.name() instead for the more familiar short path.

[vonbehr]

It's actually returning a cmdx.DagNode which when you print it calls node.path().

Right. I missed that. My bad.
I think the long path is preferably anyway.

[mottosso]

If you'd like, it would be great with a PR containing the changes you'd like to see added, then we can chat about specifics from there and also ensure the tests are all happy (performance included).

[vonbehr]

Will do.