test: Added test for init and destroy

Also changed a few things like destroy tanking a double pointer so that
is more secure and making sure before hand that capacity is not that
ridiculous of a size, still, shit can get pass but generally is fine

test/test_arraylist.c

@@ -1,5 +1,99 @@
-#include <stdlib.h>
+#include <stdalign.h>
+#include <stdarg.h>
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <setjmp.h>
+#include <cmocka.h>
+#include <string.h>
+
+#include "arraylist.h"
+
+static void test_init_valid_parameters(void **state) {
+    (void) state;
+
+    ArrayList *arr = arraylist_init(64, sizeof(int));
+    assert_ptr_not_equal(arr, NULL);
+    arraylist_destroy(&arr);
+}
+
+static void test_init_zero_capacity(void **state) {
+    (void) state;
+
+    ArrayList *arr = arraylist_init(0, sizeof(int));
+    assert_ptr_equal(arr, NULL);
+    arraylist_destroy(&arr);
+}
+
+static void test_init_zero_elem_size(void **state) {
+    (void) state;
+
+    ArrayList *arr = arraylist_init(64, 0);
+    assert_ptr_equal(arr, NULL);
+    arraylist_destroy(&arr);
+}
+
+static void test_init_large_capacity(void **state) {
+    (void) state;
+
+    ArrayList *arr = arraylist_init(SIZE_MAX, sizeof(int));
+    assert_ptr_equal(arr, NULL);
+    arraylist_destroy(&arr);
+}
+
+static void test_destroy_valid_array(void **state) {
+    (void) state;
+
+    ArrayList *arr = arraylist_init(64, sizeof(int));
+    assert_ptr_not_equal(arr, NULL);
+
+    arraylist_destroy(&arr);
+    assert_ptr_equal(arr, NULL);
+}
+
+static void test_destroy_null_array(void **state) {
+    (void) state;
+
+    ArrayList *arr = NULL;
+    ArrayListErr err = arraylist_destroy(&arr);
+
+    assert_ptr_equal(arr, NULL);
+    assert_int_equal(err, ARRLIST_NULL_ARG);
+}
+
+static void test_destroy_double(void **state) {
+    (void) state;
+
+    ArrayList *arr = arraylist_init(64, sizeof(int));
+    assert_ptr_not_equal(arr, NULL);
+
+    ArrayListErr err = arraylist_destroy(&arr);
+    assert_int_equal(err, ARRLIST_OK);
+    assert_ptr_equal(arr, NULL);
+
+    err = arraylist_destroy(&arr);
+    assert_int_equal(err, ARRLIST_NULL_ARG);
+    assert_ptr_equal(arr, NULL);
+}
 
 int main(void) {
-    return EXIT_SUCCESS;
+    const struct CMUnitTest init[] = {
+        cmocka_unit_test(test_init_valid_parameters),
+        cmocka_unit_test(test_init_zero_capacity),
+        cmocka_unit_test(test_init_zero_elem_size),
+        cmocka_unit_test(test_init_large_capacity),
+    };
+
+    const struct CMUnitTest destroy[] = {
+        cmocka_unit_test(test_destroy_valid_array),
+        cmocka_unit_test(test_destroy_null_array),
+        cmocka_unit_test(test_destroy_double),
+    };
+
+    int rc = 0;
+
+    rc += cmocka_run_group_tests(init, NULL, NULL);
+    rc += cmocka_run_group_tests(destroy, NULL, NULL);
+
+    return rc;
 }