[EMSUSD-2154] mayaUsd_ProxyTargetsSessionLayerOnOpen doesn't seem to work

[radon199]

Describe the bug
The mayaUsd_ProxyTargetsSessionLayerOnOpen option var does not appear to work for us with mayaUsdProxyShapes anymore. We should expect that the session layer is always set as the edit target, regardless of what is set in Maya when the file is saved.

Steps to reproduce
Steps to reproduce the behaviour:

1. Set the mayaUsd_ProxyTargetsSessionLayerOnOpen option var to 1.
2. Create a mayaUsdProxyShape pointing to a file.
3. Save a Maya file with the proxy shape included.
4. Close the Maya file and reopen the one saved in step 4.
5. Look at the Layer Editor and you will see that the session layer is not targeted despite the option var.

Expected behavior
The session layer should be targeted regardless of the edit target saved into the file.

Specs (if applicable):

• OS & version : Windows 10
• Compiler & version : precompiled
• Maya version : 2022.5, 2024
• Maya USD : 0.30.0

[radon199]

After some further testing we are seeing :

• Shared proxy : Edit Target is set to whatever the edit target was when the file was saved.

• Unshated proxy : Edit target is always set to the unshared layer

I think that if the set session layer option var is set, it should affect things regardless of what is saved in the file or the shared state of the proxy.

[santosg87]

thank you for the report! we are investigating this currently. logged internally as EMSUSD-2154