LGTM, thanks! Just one minor comment above to clarify shapes for the zero-size tensor.

@jcwchen I ran the commands, they did not show any files. However, after removing test_driver.cc changes the CI started passing. I have no idea why it's passing now, maybe the issue was sporadic or has been fixed on master in the meantime. Thanks for the help!

FYI: to detect similar issue (introducing new node test directories without corresponding test script) I mentioned above, I added a CI check for it by this PR: #4514.

@jcwchen I applied your suggestions, thanks! For some reason I assumed that script that generates data also removes the old files. I also approved your PR introducing a CI check for that, it sounds helpful. Test names also have been aligned.

I might figure out why previous CI has failed: some added test model files are not needed. I don't see where they are generated. For instance, test_uneven_split and test_uneven_split_opset18. I would suggest you clean all of added test files and then use python onnx/backend/test/cmd_tools.py generate-data to generated them again. Since related test was just removed due to recent ONNXIFI deprecation, I will add a similar check in CI to prevent future issues like it.

Another suggestion would be making test files naming convention consistent. For names of Split related tests, please use test_split_XXX_XXX. IMO, it will be helpful for users to search related test files.

I think it would be helpful to update the AddNewOp document (may be as a helpful Troubleshooting tip at the end) to remind people to delete the old folder before generating test-cases. (If the CI can catch it, that would be great too.)

I might figure out why previous CI has failed: some added test model files are not needed. I don't see where they are generated. For instance, test_uneven_split and test_uneven_split_opset18. I would suggest you clean all of added test files and then use python onnx/backend/test/cmd_tools.py generate-data to generated them again. Since related test was just removed due to recent ONNXIFI deprecation, I will add a similar check in CI to prevent future issues like it.
Another suggestion would be making test files naming convention consistent. For names of Split related tests, please use test_split_XXX_XXX. IMO, it will be helpful for users to search related test files.

I think it would be helpful to update the AddNewOp document (may be as a helpful Troubleshooting tip at the end) to remind people to delete the old folder before generating test-cases. (If the CI can catch it, that would be great too.)

Or, may be the test-case generator should delete the folder? (Of course, it could be a bit risky in case the user has some other file there ... may be warn the user if there is some extra files there perhaps.)

I think it would be helpful to update the AddNewOp document (may be as a helpful Troubleshooting tip at the end) to remind people to delete the old folder before generating test-cases. (If the CI can catch it, that would be great too.)

Sounds good. I will add sentence about it in AddNewOp.md in this PR as well: #4514. Also note that that PR will let CI to catch this kind of issue. Perhaps we can forward that PR first and have that verify this PR.

Or, may be the test-case generator should delete the folder? (Of course, it could be a bit risky in case the user has some other file there ... may be warn the user if there is some extra files there perhaps.)

Yes, but it seems possible that users would like to keep existing ones for some testing purposes? Therefore, to keep behavior consistent, I introduced --clean flag for generate_data for CI use (by default it is False so it won't clean original node directory automatically).