feature[next]: Runtime check args in is_call_to (#1796)

Calling `is_call_to` with the arguments in the wrong order happens
easily. This PR adds a runtime check to avoid this.

src/gt4py/next/iterator/ir_utils/common_pattern_matcher.py

@@ -7,7 +7,7 @@
 # SPDX-License-Identifier: BSD-3-Clause
 
 from collections.abc import Iterable
-from typing import TypeGuard
+from typing import Any, TypeGuard
 
 from gt4py.next.iterator import ir as itir
 from gt4py.next.iterator.ir_utils import ir_makers as im
@@ -63,10 +63,14 @@ def is_let(node: itir.Node) -> TypeGuard[itir.FunCall]:
     return isinstance(node, itir.FunCall) and isinstance(node.fun, itir.Lambda)
 
 
-def is_call_to(node: itir.Node, fun: str | Iterable[str]) -> TypeGuard[itir.FunCall]:
+def is_call_to(node: Any, fun: str | Iterable[str]) -> TypeGuard[itir.FunCall]:
     """
     Match call expression to a given function.
 
+    If the `node` argument is not an `itir.Node` the function does not error, but just returns
+    `False`. This is useful in visitors, where sometimes we pass a list of nodes or a leaf
+    attribute which can be anything.
+
     >>> from gt4py.next.iterator.ir_utils import ir_makers as im
     >>> node = im.call("plus")(1, 2)
     >>> is_call_to(node, "plus")
@@ -76,6 +80,7 @@ def is_call_to(node: itir.Node, fun: str | Iterable[str]) -> TypeGuard[itir.FunC
     >>> is_call_to(node, ("plus", "minus"))
     True
     """
+    assert not isinstance(fun, itir.Node)  # to avoid accidentally passing the fun as first argument
     if isinstance(fun, (list, tuple, set, Iterable)) and not isinstance(fun, str):
         return any((is_call_to(node, f) for f in fun))
     return (