diff -r 435c9965b2dd -r 3dc9075df822 test/test_list.c
--- a/test/test_list.c	Sat Jan 29 12:46:07 2022 +0100
+++ b/test/test_list.c	Sat Jan 29 14:32:04 2022 +0100
@@ -1001,6 +1001,92 @@
     test_hl_linked_list_iterator_impl(list);
 }
 
+void test_hl_linked_list_insert_via_iterator(void) {
+    cxTestingAllocatorReset();
+    CxList list = cxLinkedListCreate(cxTestingAllocator, cmp_int, sizeof(int));
+    for (int i = 0; i < 5; i++) {
+        cxListAdd(list, &i);
+    }
+    CxIterator iter = cxListIterator(list, 2);
+    CU_ASSERT_EQUAL(iter.index, 2)
+    CU_ASSERT_EQUAL(*(int *) cxIteratorCurrent(&iter), 2)
+
+    int data = 10;
+    cxListInsertAfter(&iter, &data);
+    CU_ASSERT_EQUAL(iter.index, 2)
+    CU_ASSERT_EQUAL(*(int *) cxIteratorCurrent(&iter), 2)
+    data = 20;
+    cxListInsertBefore(&iter, &data);
+    CU_ASSERT_EQUAL(iter.index, 3)
+    CU_ASSERT_EQUAL(*(int *) cxIteratorCurrent(&iter), 2)
+
+    data = 30;
+    iter = cxListBegin(list);
+    cxListInsertBefore(&iter, &data);
+    CU_ASSERT_EQUAL(iter.index, 1)
+    CU_ASSERT_EQUAL(*(int *) cxIteratorCurrent(&iter), 0)
+    data = 40;
+    iter = cxListIterator(list, list->size);
+    cxListInsertBefore(&iter, &data);
+    CU_ASSERT_EQUAL(iter.index, 9)
+    CU_ASSERT_FALSE(cxIteratorValid(&iter))
+    data = 50;
+    iter = cxListIterator(list, list->size);
+    cxListInsertAfter(&iter, &data);
+    CU_ASSERT_EQUAL(iter.index, 10)
+    CU_ASSERT_FALSE(cxIteratorValid(&iter))
+
+    int expdata[] = {30, 0, 1, 20, 2, 10, 3, 4, 40, 50};
+    CxList expected = cxLinkedListFromArray(cxTestingAllocator,
+                                            cmp_int, sizeof(int), 10, expdata);
+
+    CU_ASSERT_EQUAL(0, cxListCompare(list, expected))
+    cxLinkedListDestroy(list);
+    cxLinkedListDestroy(expected);
+    CU_ASSERT_TRUE(cxTestingAllocatorVerify())
+}
+
+void test_hl_ptr_linked_list_insert_via_iterator(void) {
+    int testdata[] = {0, 1, 2, 3, 4, 10, 20, 30, 40, 50};
+    cxTestingAllocatorReset();
+    CxList list = cxPointerLinkedListCreate(cxTestingAllocator, cmp_int);
+    int i;
+    for (i = 0; i < 5; i++) {
+        cxListAdd(list, &testdata[i]);
+    }
+    CxIterator iter = cxListIterator(list, 2);
+    CU_ASSERT_EQUAL(iter.index, 2)
+    CU_ASSERT_EQUAL(*(int *) cxIteratorCurrent(&iter), 2)
+
+    cxListInsertAfter(&iter, &testdata[i++]);
+    CU_ASSERT_EQUAL(iter.index, 2)
+    CU_ASSERT_EQUAL(*(int *) cxIteratorCurrent(&iter), 2)
+    cxListInsertBefore(&iter, &testdata[i++]);
+    CU_ASSERT_EQUAL(iter.index, 3)
+    CU_ASSERT_EQUAL(*(int *) cxIteratorCurrent(&iter), 2)
+
+    iter = cxListBegin(list);
+    cxListInsertBefore(&iter, &testdata[i++]);
+    CU_ASSERT_EQUAL(iter.index, 1)
+    CU_ASSERT_EQUAL(*(int *) cxIteratorCurrent(&iter), 0)
+    iter = cxListIterator(list, list->size);
+    cxListInsertBefore(&iter, &testdata[i++]);
+    CU_ASSERT_EQUAL(iter.index, 9)
+    CU_ASSERT_FALSE(cxIteratorValid(&iter))
+    iter = cxListIterator(list, list->size);
+    cxListInsertAfter(&iter, &testdata[i++]);
+    CU_ASSERT_EQUAL(iter.index, 10)
+    CU_ASSERT_FALSE(cxIteratorValid(&iter))
+
+    int expdata[] = {30, 0, 1, 20, 2, 10, 3, 4, 40, 50};
+    for (i = 0; i < 10; i++) {
+        CU_ASSERT_EQUAL(*(int *) cxListAt(list, i), expdata[i])
+    }
+
+    cxLinkedListDestroy(list);
+    CU_ASSERT_TRUE(cxTestingAllocatorVerify())
+}
+
 int main() {
     CU_pSuite suite = NULL;
 
@@ -1037,6 +1123,7 @@
     cu_add_test(suite, test_hl_linked_list_find);
     cu_add_test(suite, test_hl_linked_list_sort);
     cu_add_test(suite, test_hl_linked_list_iterator);
+    cu_add_test(suite, test_hl_linked_list_insert_via_iterator);
 
     suite = CU_add_suite("high level pointer linked list", NULL, NULL);
 
@@ -1048,6 +1135,7 @@
     cu_add_test(suite, test_hl_ptr_linked_list_find);
     cu_add_test(suite, test_hl_ptr_linked_list_sort);
     cu_add_test(suite, test_hl_ptr_linked_list_iterator);
+    cu_add_test(suite, test_hl_ptr_linked_list_insert_via_iterator);
 
     CU_basic_set_mode(UCX_CU_BRM);