Ensure shapes passed to mb.fill are int (#1850)

Ensure shapes passed to `mb.fill` are `int`, with test cases.

Author: pcuenca

coremltools/converters/mil/frontend/torch/ops.py

@@ -3594,6 +3594,8 @@ def _make_fill_op(size, val, name):
     assert val is not None
     if isinstance(size, list):
         size = mb.concat(values=size, axis=0)
+    if types.is_float(size.dtype):
+        size = mb.cast(x=size, dtype="int32")
     fill = mb.fill(shape=size, value=val, name=name)
     return fill
 

coremltools/converters/mil/frontend/torch/test/test_torch_ops.py

@@ -3531,6 +3531,29 @@ def forward(self, x):
             shape, FullStaticModel().eval(), backend=backend, compute_unit=compute_unit
         )
 
+    @pytest.mark.parametrize(
+        "compute_unit, backend, shape_val",
+        itertools.product(
+            compute_units,
+            backends,
+            [
+                [(1,), 0.0],
+                [(2, 3), 3.1415],
+                [(1, 1, 2, 5, 1), -2.0],
+            ],
+        ),
+    )
+    def test_full_scalar(self, compute_unit, backend, shape_val):
+        shape, val = shape_val
+
+        class FullScalarModel(nn.Module):
+            def forward(self, x):
+                return x / torch.full([], fill_value=val)
+
+        self.run_compare_torch(
+            shape, FullScalarModel().eval(), backend=backend, compute_unit=compute_unit
+        )
+
     @pytest.mark.parametrize(
         "compute_unit, backend, shape_val",
         itertools.product(