feat: implement quick sort

1 files changed, 65 insertions, 0 deletions

diff --git a/src/03/sort_test.c b/src/03/sort_test.c
index 8c01b04..fabb4ee 100644
--- a/src/03/sort_test.c
+++ b/src/03/sort_test.c
@@ -64,6 +64,64 @@ Ensure(merge_sort_sorts_many_items) {
   assert_that(items[10], is_equal_to(9));
 }
 
+Ensure(quick_sort_sorts_a_null_list) {
+  quick_sort(NULL, 0);
+}
+
+Ensure(quick_sort_sorts_an_empty_list) {
+  int items[] = {};
+
+  quick_sort(items, 0);
+
+  assert_that(sizeof(items), is_equal_to(0));
+}
+
+Ensure(quick_sort_sorts_a_list_with_one_item) {
+  int items[] = {100};
+
+  quick_sort(items, 1);
+
+  assert_that(items[0], is_equal_to(100));
+}
+
+Ensure(quick_sort_sorts_a_list_with_two_items) {
+  int items[] = {100, 10};
+
+  quick_sort(items, 2);
+
+  assert_that(items[0], is_equal_to(10));
+  assert_that(items[1], is_equal_to(100));
+}
+
+Ensure(quick_sort_sorts_three_unique_items) {
+  int items[] = { 3, 1, 4 };
+
+  quick_sort(items, sizeof(items) / sizeof(int));
+
+  assert_that(items[0], is_equal_to(1));
+  assert_that(items[1], is_equal_to(3));
+  assert_that(items[2], is_equal_to(4));
+}
+
+Ensure(quick_sort_sorts_many_items) {
+  int items[] = { 3, 1, 4, 1, 5, 9, 2, 6, 5, 3, 5 };
+
+  quick_sort(items, sizeof(items) / sizeof(int));
+
+  assert_that(items[0], is_equal_to(1));
+  assert_that(items[1], is_equal_to(1));
+  assert_that(items[2], is_equal_to(2));
+  assert_that(items[3], is_equal_to(3));
+  assert_that(items[4], is_equal_to(3));
+  assert_that(items[5], is_equal_to(4));
+  assert_that(items[6], is_equal_to(5));
+  assert_that(items[7], is_equal_to(5));
+  assert_that(items[8], is_equal_to(5));
+  assert_that(items[9], is_equal_to(6));
+  assert_that(items[10], is_equal_to(9));
+}
+
+
 TestSuite *sort_tests() {
   TestSuite *x = create_test_suite();
   add_test(x, one_equals_one);
@@ -74,5 +132,12 @@ TestSuite *sort_tests() {
   add_test(x, merge_sort_sorts_a_list_with_two_items);
   add_test(x, merge_sort_sorts_three_unique_items);
   add_test(x, merge_sort_sorts_many_items);
+
+  add_test(x, quick_sort_sorts_a_null_list);
+  add_test(x, quick_sort_sorts_an_empty_list);
+  add_test(x, quick_sort_sorts_a_list_with_one_item);
+  add_test(x, quick_sort_sorts_a_list_with_two_items);
+  add_test(x, quick_sort_sorts_three_unique_items);
+  add_test(x, quick_sort_sorts_many_items);
   return x;
 }