Can't generate Constant nodes with attributes as vectors

[vera121]

I find there are some bugs when trying to use attributes as vector for constant node input inside a local function, i.e.

These codes could work:

from onnxscript import opset18 as op
from onnxscript import script

import numpy as np


@script()
def LocalFunc(X, alpha: int):
    alphaX = op.Constant(value_int=alpha)
    gammaX = op.Constant(value_ints=[1, 2])
    Add = alphaX + X + gammaX
    return Add


v = np.array([[0, 1], [2, 3]], dtype=np.int64)
result = LocalFunc(v, 1)
print(result)

But this snippet would report errors:

@script()
def LocalFunc1(X, alpha: int, gamma: int):
    alphaX = op.Constant(value_ints=[alpha, gamma])
    Add = alphaX + X
    return Add


v = np.array([[0, 1], [2, 3]], dtype=np.int64)
result = LocalFunc1(v, 1, 2)
print(result)

Errors are like

...
onnxscript\converter.py", line 471, in _eval_constant_expr
    return eval(cpl, self.globals, locals)  # pylint: disable=eval-used
  File "<ast>", line 3, in <module>
NameError: name 'alpha' is not defined
...

NameError: ERROR: Missing names, globals contains ['__name__', '__doc__', '__package__', '__loader__', '__spec__', '__annotations__', '__builtins__', '__file__', '__cached__', 'op', 'script', 'np', 'LocalFunc', 'v', 'result'], locals [].
at: Function 'LocalFunc1', line 3
    alphaX = op.Constant(value_ints=[alpha, gamma])
                                    ^

I think there might be a bug in the Constant node conversion, and such bug makes it hard for us to use multiple attributes directly in local function design.
Could you fix it?

[justinchuby]

This is a known limitation, since the attribute in value_ints in op.Constant(value_ints=...) can only be a constant for a reference, it cannot be [alpha, gamma] which is a computed value. It is a construct not supported by ONNX.

Instead, consider using Concat or construct the constant before passing it into the function if possible.