Report integer_array_t arguments made during elaboration as a failure

docs/types.rst

@@ -37,8 +37,11 @@ integer_array_t and NumPy
 
 An ``integer_array_t`` argument is transferred to Python and referred to by
 the expression as a NumPy array of dtype ``int32``, so it can be reused in
-several calls. It is indexed like VUnit, so that elements correspond
-directly:
+several calls. Since it is transferred when the argument is made, the
+argument must be made after ``test_runner_setup``, not during elaboration, for
+example in a constant. Otherwise ``arg`` and ``kwarg`` report a failure, see
+`#17 <https://github.com/VUnit/vunit-python-bridge/issues/17>`__. It is
+indexed like VUnit, so that elements correspond directly:
 
 ============= ================================ ===========================
 Array         VHDL                             Python

release_notes/news.d/29.bugfix.md

@@ -0,0 +1 @@
+An `integer_array_t` argument made before `test_runner_setup`, for example in a constant during elaboration, is reported as a failure naming the call, instead of crashing the simulator (NVC: "foreign function vpy_push_array not found", GHDL: CONSTRAINT_ERROR). See #17.

src/vunit_python_bridge/hdl/src/python_ffi_pkg_bridge.vhd

@@ -26,6 +26,8 @@ use vunit_lib.id_pkg.all;
 use vunit_lib.integer_array_pkg.all;
 use vunit_lib.integer_vector_ptr_pkg.all;
 use vunit_lib.logger_pkg.all;
+use vunit_lib.run_pkg.get_phase;
+use vunit_lib.run_types_pkg.all;
 use work.python_bridge_pkg.all;
 
 package python_ffi_pkg is
@@ -412,6 +414,14 @@ package body python_ffi_pkg is
     variable offset, n : natural := 0;
     variable staged_id : integer;
   begin
+    if get_phase < test_runner_setup then
+      failure(
+        python_logger,
+        operation & " failed:" & LF &
+        "An integer_array_t argument cannot be made before test_runner_setup."
+      );
+      return -1;
+    end if;
     if not p_succeeded(
       vpy_push_array(len, width(arr), height(arr), depth(arr), bit_width(arr), boolean'pos(is_signed(arr))),
       operation

tests/run.py

@@ -39,6 +39,10 @@
     "lib.tb_python_pkg.Test eval of real with underflow from C to VHDL",
 ]
 
+# Fails during elaboration, with this error rather than a crash, see #17
+ELABORATION_ARRAY_TEST = "lib.tb_elaboration_array.all"
+ELABORATION_ARRAY_ERROR = "An integer_array_t argument cannot be made before test_runner_setup"
+
 # Simulators where python_pkg is implemented by the VUnit Python bridge
 BRIDGE_SIMULATORS = ["nvc", "ghdl", "modelsim"]
 
@@ -67,6 +71,11 @@ def verify(results, expected_failures):
     if missing:
         raise RuntimeError("Tests expected to fail but did not:\n" + "\n".join(missing))
 
+    if ELABORATION_ARRAY_TEST in expected and ELABORATION_ARRAY_ERROR not in (
+        tests[ELABORATION_ARRAY_TEST].path / "output.txt"
+    ).read_text(encoding="utf-8"):
+        raise RuntimeError(f"{ELABORATION_ARRAY_TEST} failed without the error: {ELABORATION_ARRAY_ERROR}")
+
     if expected:
         print(f"Verified {len(expected)} expected failures: {', '.join(name.split('.')[-1] for name in expected)}")
 
@@ -113,6 +122,8 @@ def main():
     if simulator_name in BRIDGE_SIMULATORS:
         # The operations implemented by the Python bridge
         lib.add_source_file(ROOT / "tb_python_pkg_bridge.vhd")
+        lib.add_source_file(ROOT / "tb_elaboration_array.vhd")
+        expected_failures.append(ELABORATION_ARRAY_TEST)
 
     vu.set_compile_option("rivierapro.vcom_flags", ["-dbg"])
     vu.set_sim_option("rivierapro.vsim_flags", ["-interceptcoutput"])

tests/tb_elaboration_array.vhd

@@ -0,0 +1,38 @@
+-- This Source Code Form is subject to the terms of the Mozilla Public
+-- License, v. 2.0. If a copy of the MPL was not distributed with this file,
+-- You can obtain one at http://mozilla.org/MPL/2.0/.
+--
+-- Copyright (c) 2014-2026, Lars Asplund lars.anders.asplund@gmail.com
+--
+-- An integer_array_t argument made during elaboration must fail with a clear
+-- error, not crash the simulator, see #17. tests/run.py expects it to fail
+-- and checks the error.
+
+library vunit_lib;
+context vunit_lib.vunit_context;
+library python_bridge;
+context python_bridge.python_context;
+
+entity tb_elaboration_array is
+  generic(runner_cfg : string);
+end entity;
+
+architecture tb of tb_elaboration_array is
+  impure function one_to_four return integer_array_t is
+    variable values : integer_array_t := new_1d(4);
+  begin
+    for idx in 0 to 3 loop
+      set(values, idx, idx + 1);
+    end loop;
+    return values;
+  end;
+
+  constant values_arg : arg_t := arg(one_to_four);
+begin
+  main : process
+  begin
+    test_runner_setup(runner, runner_cfg);
+    check_equal(integer'(call("sum", values_arg)), 10);
+    test_runner_cleanup(runner);
+  end process;
+end architecture;