1 files changed, 25 insertions, 1 deletions

diff --git a/test/morpher/quadrilateral.c b/test/morpher/quadrilateral.c
index 963d1d6..b278e2f 100644
--- a/test/morpher/quadrilateral.c
+++ b/test/morpher/quadrilateral.c
@@ -21,7 +21,6 @@ static inline bool vertices_equals(CartesianMapping maps[],
  */
 static void test_quadrilateral_flip_diagonal() {
   CartesianMapping A = m(50, 0), B = m(0, 100), C = m(100, 100), D = m(0, 200), E = m(100, 200);
-
   TriangleMap *t = trianglemap_create(A, B, C);
   TriangleMap *r = trianglemap_create(C, B, E);
   TriangleMap *l = trianglemap_create(B, D, E);
@@ -54,9 +53,34 @@ static void test_quadrilateral_is_delaunay(CartesianMapping A, CartesianMapping
   trianglemap_destroy(r);
 }
 
+static void test_quadrilateral_propagate_delaunay() {
+  CartesianMapping A = m(0, 0), B = m(0, 10), C = m(10, 10), D = m(10, 0), E = m(4, 6), F = m(8, 7);
+  TriangleMap *l = trianglemap_create(A, B, C);
+  TriangleMap *r = trianglemap_create(A, C, D);
+  trianglemap_set_neighbors(l, NULL, NULL, r, r);
+  trianglemap_set_neighbors(r, l, NULL, NULL, NULL);
+  trianglemap_split(l, E);
+  trianglemap_split(r, F);
+
+  trianglemap_foreach_neighbor(r, quadrilateral_propagate_delaunay);
+
+  {
+    TriangleMap *triangle;
+    int neighbor_index;
+    for (triangle = l; triangle != NULL; triangle = triangle->next)
+      for (neighbor_index = 0; neighbor_index < 3; ++neighbor_index)
+        if (triangle->neighbors[neighbor_index] != NULL)
+          assert(quadrilateral_is_delaunay(triangle, triangle->neighbors[neighbor_index]));
+  }
+
+  trianglemap_destroy(l);
+  trianglemap_destroy(r);
+}
+
 int main(int argc, char **argv) {
   test_quadrilateral_flip_diagonal();
   test_quadrilateral_is_delaunay(m(0, 0), m(0, 3), m(3, 3), m(2, 1), false);
   test_quadrilateral_is_delaunay(m(0, 0), m(0, 3), m(3, 3), m(4, -1), true);
+  test_quadrilateral_propagate_delaunay();
   return 0;
 }