fix(frontend-python): stop crashing on scalar squeeze

frontends/concrete-python/concrete/fhe/mlir/converter.py

@@ -521,6 +521,9 @@ def squeeze(self, ctx: Context, node: Node, preds: List[Conversion]) -> Conversi
         # if the output shape is (), it means (1, 1, ..., 1, 1) is squeezed
         # and the result is a scalar, so we need to do indexing, not reshape
         if node.output.shape == ():
+            if preds[0].shape == ():
+                return preds[0]
+
             assert all(size == 1 for size in preds[0].shape)
             index = (0,) * len(preds[0].shape)
             return ctx.index_static(ctx.typeof(node), preds[0], index)

frontends/concrete-python/tests/execution/test_others.py

@@ -659,6 +659,13 @@ def copy_modify(x):
             },
             id="x ** 3",
         ),
+        pytest.param(
+            lambda x: np.squeeze(x),
+            {
+                "x": {"status": "encrypted", "range": [-10, 10], "shape": ()},
+            },
+            id="np.squeeze(x)",
+        ),
         pytest.param(
             lambda x: np.squeeze(x),
             {