// Copyright (c) 2026 Petr Balvín <opensource@petrbalvin.org> (https://petrbalvin.org)
// SPDX-License-Identifier: MIT

package integrate

import "testing"

// TestSolvePoissonFEM2DNilMeshRefused pins the nil-mesh refusal: the
// three-dimensional solve reports a nil mesh as an error, so the
// two-dimensional one answers the same way instead of dereferencing
// it and panicking.
func TestSolvePoissonFEM2DNilMeshRefused(t *testing.T) {
	_, err := SolvePoissonFEM2D(nil, nil, FEMPoissonOptions{
		Kappa:           1,
		DirichletNodes:  []int{0},
		DirichletValues: []float64{0},
	})
	if err == nil {
		t.Fatal("SolvePoissonFEM2D: expected an error for a nil mesh")
	}
}