Add test cases (using Google Test framework as shown in class), particularly for edge cases, and fix any bugs and memory leaks in the code below. Most functions should probably have at least three test cases. Also add this feature: Print the linked list. This function should be provided a function pointer for printing each element (since they're void pointers, the linked list code cannot know how to print the values without being provided such a function). Print starting at the current element until the end of the list (when current element cycles back around) linkedlist.cpp #include "linkedlist.h" Linkedlist "new_list() { Linkedlist "list - new LinkedList; list->cur - nullptr; return list; void push(Linkedlist "list, void *val) { Node *node = new Node; node->val = val; node->next = list->cur->next; node->prev - list->cur; linkedlist.cpp #include "linkedlist.h" LinkedList "new_list() { LinkedList "list - new LinkedList; list->cur = nullptr; return list; void push(LinkedList "list, void *val) { Node "node = new Node; node->val - val; node->next = list->cur->next; node->prev = list->cur; void *peek(Linkedlist "list) { if(list->cur != nullptr) { return list->cur->val; return nullptr; return list->cur->val; return nullptr; void forward(Linkedlist "list) { list->cur = list->cur->next; void backward (LinkedList "list) { list->cur = list->cur->prev; void "pop(LinkedList "list) void "val - list->cur->val; Node "tmp-list->cur; list->cur - tmp->next; tmp->prev->next = list->cur; list->cur->prev = tmp->prev; delete tmp: return val; void delete_list(Linkedlist "list) { delete tmp return val; void delete_list(LinkedList "list) { Node "start = list->cur; list->cur - list->cur->next; while(start Ilist->cur) { Node "next = list->cur->next; delete list->cur; list->cur - next; int list_count(LinkedList "list) { int count - 1; Node "start - list->cur; list->cur = list->cur->next; while(start ! - list->cur) { count++; return count; linkedlist.h struct Node { void *val; Node "next; Node "prev; }; struct Linkedlist { Node "cur; Linkedlist "new_list(); // add node to right of cur void push(LinkedList "list, void *val); // get value from cur node void *peek(Linkedlist "list); // delete cur node and return its value void *pop(Linkedlist "list); // move cur forward (right) void forward(LinkedList "list); // move cur backward (left) void backward (LinkedList "list); Node "prev; struct LinkedList { Node "cur; Linkedlist *new_list(); // add node to right of cur void push(Linkedlist "list, void *val); // get value from cur node void "peek (Linkedlist "list); // delete cur node and return its value void "pop(LinkedList "list); // move cur forward (right) void forward(Linkedlist "list); // move cur backward (left) void backward (Linkedlist "list); // clean up memory void delete_list(linkedlist "list); // count items int list_count(LinkedList "list); test.cpp #include using namespace std; #include "gtest/gtest.h" #include "linkedlist.h" TEST(list, blank) { Linkedlist "list = new_list(); ASSERT_EQ(list->cur, nullptr); delete_list(list); TEST(list, push_to_blank_double) Linkedlist "list - new_list(); double val = 55.0; push(list, &val); ASSERT_NE(list->cur, nullptr); ASSERT_EQ(peek(list), &val); delete_list(list); push(115t, xval) ASSERT_NE(list->cur, nullptr); ASSERT_EQ(peek(list), &val); delete_list(list); TEST(list, push_to_blank_struct) { struct Student { double gpa; int year; Linkedlist *list = new list(); Student s; s.gpa - 3.5; s.year = 3; push(list, &s); ASSERT_NE (list->cur, nullptr); ASSERT_EQ(((Student*) peek(list))->gpa, 3.5); delete_list(list); Makefile GTEST_DIR - /opt/google-test/googletest CXX = 8++ CXXFLAGS = -std=C++11 -Wall - $(GTEST_DIR)/lib-isystem $(GTEST_DIR)/include - Wextra-lpthread all: test test: test.o linkedlist.o $(CXX) $(CXXFLAGS) -o test test.o linkedlist.o S(GTEST_DIR)/lib/libgtest_main.a $(GTEST_DIR)/lib/libgtest.a test.o: test.cpp linkedlist.h $(CXX) $(CXXFLAGS) - test.cpp linkedlist.o: linkedlist.cpp linkedlist.h $(CXX) $(CXXFLAGS) -c linkedlist.cpp .PHONY: clean clean: rm - f test .o Add test cases (using Google Test framework as shown in class), particularly for edge cases, and fix any bugs and memory leaks in the code below. Most functions should probably have at least three test cases. Also add this feature: Print the linked list. This function should be provided a function pointer for printing each element (since they're void pointers, the linked list code cannot know how to print the values without being provided such a function). Print starting at the current element until the end of the list (when current element cycles back around) linkedlist.cpp #include "linkedlist.h" Linkedlist "new_list() { Linkedlist "list - new LinkedList; list->cur - nullptr; return list; void push(Linkedlist "list, void *val) { Node *node = new Node; node->val = val; node->next = list->cur->next; node->prev - list->cur; linkedlist.cpp #include "linkedlist.h" LinkedList "new_list() { LinkedList "list - new LinkedList; list->cur = nullptr; return list; void push(LinkedList "list, void *val) { Node "node = new Node; node->val - val; node->next = list->cur->next; node->prev = list->cur; void *peek(Linkedlist "list) { if(list->cur != nullptr) { return list->cur->val; return nullptr; return list->cur->val; return nullptr; void forward(Linkedlist "list) { list->cur = list->cur->next; void backward (LinkedList "list) { list->cur = list->cur->prev; void "pop(LinkedList "list) void "val - list->cur->val; Node "tmp-list->cur; list->cur - tmp->next; tmp->prev->next = list->cur; list->cur->prev = tmp->prev; delete tmp: return val; void delete_list(Linkedlist "list) { delete tmp return val; void delete_list(LinkedList "list) { Node "start = list->cur; list->cur - list->cur->next; while(start Ilist->cur) { Node "next = list->cur->next; delete list->cur; list->cur - next; int list_count(LinkedList "list) { int count - 1; Node "start - list->cur; list->cur = list->cur->next; while(start ! - list->cur) { count++; return count; linkedlist.h struct Node { void *val; Node "next; Node "prev; }; struct Linkedlist { Node "cur; Linkedlist "new_list(); // add node to right of cur void push(LinkedList "list, void *val); // get value from cur node void *peek(Linkedlist "list); // delete cur node and return its value void *pop(Linkedlist "list); // move cur forward (right) void forward(LinkedList "list); // move cur backward (left) void backward (LinkedList "list); Node "prev; struct LinkedList { Node "cur; Linkedlist *new_list(); // add node to right of cur void push(Linkedlist "list, void *val); // get value from cur node void "peek (Linkedlist "list); // delete cur node and return its value void "pop(LinkedList "list); // move cur forward (right) void forward(Linkedlist "list); // move cur backward (left) void backward (Linkedlist "list); // clean up memory void delete_list(linkedlist "list); // count items int list_count(LinkedList "list); test.cpp #include using namespace std; #include "gtest/gtest.h" #include "linkedlist.h" TEST(list, blank) { Linkedlist "list = new_list(); ASSERT_EQ(list->cur, nullptr); delete_list(list); TEST(list, push_to_blank_double) Linkedlist "list - new_list(); double val = 55.0; push(list, &val); ASSERT_NE(list->cur, nullptr); ASSERT_EQ(peek(list), &val); delete_list(list); push(115t, xval) ASSERT_NE(list->cur, nullptr); ASSERT_EQ(peek(list), &val); delete_list(list); TEST(list, push_to_blank_struct) { struct Student { double gpa; int year; Linkedlist *list = new list(); Student s; s.gpa - 3.5; s.year = 3; push(list, &s); ASSERT_NE (list->cur, nullptr); ASSERT_EQ(((Student*) peek(list))->gpa, 3.5); delete_list(list); Makefile GTEST_DIR - /opt/google-test/googletest CXX = 8++ CXXFLAGS = -std=C++11 -Wall - $(GTEST_DIR)/lib-isystem $(GTEST_DIR)/include - Wextra-lpthread all: test test: test.o linkedlist.o $(CXX) $(CXXFLAGS) -o test test.o linkedlist.o S(GTEST_DIR)/lib/libgtest_main.a $(GTEST_DIR)/lib/libgtest.a test.o: test.cpp linkedlist.h $(CXX) $(CXXFLAGS) - test.cpp linkedlist.o: linkedlist.cpp linkedlist.h $(CXX) $(CXXFLAGS) -c linkedlist.cpp .PHONY: clean clean: rm - f test .o