[Bugfix] Add triton.language.tensor placeholder

[adobrzyn]

Fix issue:
AttributeError: module 'triton.language' has no attribute 'tensor'

As LanguagePlaceholder doesn't have this field that is being used in compute_identity_kernel in vllm/model_executor/layers/fused_moe/fused_moe.py:670

Regression after: #23991

[gemini-code-assist]

Code Review

This pull request correctly addresses the AttributeError by adding the tensor attribute to the TritonLanguagePlaceholder. The fix is straightforward and aligns with the existing implementation of the placeholder class. However, to ensure this bug does not reappear in the future, it's important to add a corresponding test case. I've left a specific comment regarding updating the tests.

[gemini-code-assist]

This change correctly adds the tensor attribute. To prevent future regressions, please also update the corresponding unit test in tests/test_triton_utils.py.

The test_triton_placeholder_language function is incomplete and should be updated to check for all attributes of TritonLanguagePlaceholder, including the newly added tensor.

Here is a suggested update for the test:

def test_triton_placeholder_language():
    lang = TritonLanguagePlaceholder()
    assert isinstance(lang, types.ModuleType)
    assert lang.__name__ == "triton.language"
    assert lang.constexpr is None
    assert lang.dtype is None
    assert lang.int64 is None
    assert lang.int32 is None
    assert lang.tensor is None

[adobrzyn]

I added both int32 and tensor attribute

[bigPYJ1151]

Thanks for the fix!