Fail on spice netlist error

cpp/VpiCallbacks.cpp

@@ -233,6 +233,10 @@ auto vpi_start_of_sim_cb(p_cb_data cb_data_p) -> PLI_INT32 {
 
     if (ngSpice_Init_Sync(ng_srcdata, nullptr, ng_sync, nullptr, nullptr) == 0) {
         ngSpice_Command((char *)"bg_run");
+        if (ngSpice_running()==0) {
+            ERROR("Failed to initialize run ngspice.");
+            return 1;
+        }
     } else {
         ERROR("Failed to initialize ngSpice_Init_Sync interface.");
         return 1;

tests/error.cir

@@ -0,0 +1,7 @@
+* test error 
+
+Vdd vdd 0 {ERROR_PARAM}
+
+.tran 1ns 1
+
+.end

tests/error.v

@@ -0,0 +1,16 @@
+`timescale 1ns/1ps
+
+module error_cir();
+
+endmodule
+
+module error_tb();
+
+    error_cir error_cir ();
+
+    initial begin
+        $dumpfile("error.vcd");
+        $dumpvars (0);
+    end
+
+endmodule

tests/test_error.py

@@ -0,0 +1,37 @@
+import cocotb
+from cocotb.triggers import Timer
+from cocotb.runner import get_runner
+import os
+from pathlib import Path
+import spicebind
+import pytest
+
+@cocotb.test()
+async def run_error_test(dut):
+    await Timer(10, units="ns")
+    # assert False, "Error"
+
+@pytest.mark.xfail(reason="Expected error from spice simulation")
+def test_error():
+    proj_path = Path(__file__).resolve().parent
+    sources = [proj_path / "error.v"]
+
+    sim = os.getenv("SIM", "icarus")
+
+    runner = get_runner(sim)
+    runner.build(
+        sources=sources,
+        hdl_toplevel="error_tb",
+        always=True,
+    )
+
+    runner.test(
+        hdl_toplevel="error_tb",
+        test_module="test_error,",
+        test_args=["-M", spicebind.get_lib_dir(), "-m", "spicebind_vpi"],
+        extra_env={"SPICE_NETLIST": str(proj_path / "error.cir"), "HDL_INSTANCE": "error_tb.error_cir"},
+    )
+
+
+if __name__ == "__main__":
+    test_error()