WIP: Implemented a int-only deque with limited capabilities

include/pocketpy/collections.h

@@ -4,22 +4,154 @@
 #include "common.h"
 #include "memory.h"
 #include "str.h"
+#include "iter.h"
 #include "cffi.h"
 
 namespace pkpy
 {
+    struct DequeNode{
+        int obj; //TODO: change to PyObject*
+        DequeNode* prev;
+        DequeNode* next;
+        DequeNode(){
+            this->obj = -1; // ignored value
+            this->prev = nullptr;
+            this->next = nullptr;
+        }
+        DequeNode(int obj){
+            this->obj = obj;
+            this->prev = nullptr;
+            this->next = nullptr;
+        }
+        
+        ~DequeNode(){
+        }
+
+        void printNode(){
+            printf("%d ", this->obj);
+        }
+    };
+
+    struct MyDoublyLinkedList{
+        int len;
+        DequeNode* head;
+        DequeNode* tail;
+
+        MyDoublyLinkedList(){ //creates an empty list
+            this->len = 0;
+            this->head = new DequeNode(); // dummy
+            this->tail = new DequeNode(); // dummy
+            this->head->next = this->tail;
+            this->tail->prev = this->head;
+        }
+
+        ~MyDoublyLinkedList(){
+            if(this->head == nullptr) return;
+            this->makeListEmpty();
+            delete this->head;
+            delete this->tail;
+        }
+
+        void push_back(DequeNode* node){
+            node->prev = this->tail->prev;
+            node->next = this->tail;
+            this->tail->prev->next = node;
+            this->tail->prev = node;
+            this->len++;
+        }
+        void push_front(DequeNode* node){
+            node->prev = this->head;
+            node->next = this->head->next;
+            this->head->next->prev = node;
+            this->head->next = node;
+            this->len++;
+        }
+
+        DequeNode* pop_back(){
+            if(this->empty()) throw std::runtime_error("DoubleLinkedList::pop_back() called on empty list");
+            DequeNode* node = this->tail->prev;
+            this->tail->prev->prev->next = this->tail;
+            this->tail->prev = this->tail->prev->prev;
+            this->len--;
+            return node;
+        }
+
+        DequeNode* pop_front(){
+            if(this->empty()) throw std::runtime_error("DoubleLinkedList::pop_front() called on empty list");
+            DequeNode* node = this->head->next;
+            this->head->next->next->prev = this->head;
+            this->head->next = this->head->next->next;
+            this->len--;
+            return node;
+        }
+
+        bool empty() const {
+            if(this->len == 0){
+                if(this->head->next != this->tail || this->tail->prev != this->head){
+                    throw std::runtime_error("DoubleLinkedList::size() returned 0 but the list is not empty");
+                }
+                return true;
+            }
+            return false;
+        }
+
+        int count(int obj){ // TODO: change to PyObject*
+            int cnt = 0;
+            DequeNode* p = this->head->next;
+            while(p != this->tail){
+                if(p->obj == obj) cnt++;
+                p = p->next;
+            }
+            return cnt;
+        }
+
+        void makeListEmpty(){
+            while(!this->empty()){
+                this->pop_back();
+            }
+        }
+        
+        void printList(){
+            if(this->empty()){
+                printf("Empty List\n");
+                return;
+            }
+            DequeNode* p = this->head->next;
+            while(p != this->tail){
+                p->printNode();
+                p = p->next;
+            }
+            printf("\n");
+        }
+
+        
+    };
+
+    // STARTING HERE
     struct PyDeque
     {
         PY_CLASS(PyDeque, collections, deque);
 
         // some fields can be defined here
         int len;
+        MyDoublyLinkedList *dequeItems;
         
-        PyDeque() = default;
+
+        void appendLeft(int item); // TODO: change to PyObject*
+        void append(int item); // TODO: change to PyObject*
+        int popLeft(); // TODO: change to PyObject*
+        int pop(); // TODO: change to PyObject*
+        int count(int obj); // TODO: change to PyObject*
+        
+        void clear();
+        void print(VM *vm);
+
+        PyDeque(): len(0), dequeItems(new MyDoublyLinkedList()){}
+        PyDeque(VM *vm) : len(0), dequeItems(new MyDoublyLinkedList()){}
         void printHelloWorld();
         static void _register(VM *vm, PyObject *mod, PyObject *type);
 
-        void _gc_mark() const;  // needed for container types
+        void _gc_mark() const; // needed for container types
     };
 
     void add_module_mycollections(VM *vm);

src/collections.cpp

@@ -7,22 +7,140 @@ namespace pkpy
 		vm->bind_default_constructor<PyDeque>(type);
 
 		vm->bind(type, "__len__(self) -> int",
-				 [](VM *vm, ArgsView args){
-					PyDeque& self = _CAST(PyDeque&, args[0]);
-					return VAR(self.len); 
-			});
+				 [](VM *vm, ArgsView args)
+				 {
+					 PyDeque &self = _CAST(PyDeque &, args[0]);
+					 return VAR(self.len);
+				 });
 
 		vm->bind(type, "printHelloWorld(self) -> None",
-				 [](VM *vm, ArgsView args){
-					PyDeque& self = _CAST(PyDeque&, args[0]);
-					self.printHelloWorld();
-					return vm->None;
-			});
+				 [](VM *vm, ArgsView args)
+				 {
+					 printf("TESTING HELLO WORLD!!\n");
+
+					 PyDeque &self = _CAST(PyDeque &, args[0]);
+					 self.printHelloWorld();
+
+					 printf("TESTED HELLO WORLD!!\n");
+					 return vm->None;
+				 });
+
+		vm->bind(type, "appendleft(self, item) -> None",
+				 [](VM *vm, ArgsView args)
+				 {
+					 PyDeque &self = _CAST(PyDeque &, args[0]);
+					 int item = _CAST(int, args[1]); // TODO: change to PyObject*
+					 self.appendLeft(item);
+					 return vm->None;
+				 });
+
+		vm->bind(type, "append(self, item) -> None",
+				 [](VM *vm, ArgsView args)
+				 {
+					 PyDeque &self = _CAST(PyDeque &, args[0]);
+					 int item = _CAST(int, args[1]); //	TODO: change to PyObject*
+					 self.append(item);
+					 return vm->None;
+				 });
+
+		vm->bind(type, "popleft(self) -> PyObject",
+				 [](VM *vm, ArgsView args)
+				 {
+					 PyDeque &self = _CAST(PyDeque &, args[0]);
+					 int tmp = self.popLeft(); // TODO: change to PyObject*
+					 return py_var(vm, tmp);
+				 });
+
+		vm->bind(type,"pop(self) -> PyObject",
+				 [](VM *vm, ArgsView args)
+				 {
+					 PyDeque &self = _CAST(PyDeque &, args[0]);
+					 int tmp = self.pop(); // TODO: change to PyObject*
+					 return py_var(vm, tmp);
+				 });
+
+
+		vm->bind(type, "count(self, obj) -> int",
+				 [](VM *vm, ArgsView args)
+				 {
+					 PyDeque &self = _CAST(PyDeque &, args[0]);
+					 int obj = _CAST(int, args[1]); // TODO: change to PyObject*
+					 int cnt = self.count(obj);
+					 return VAR(cnt);
+				 });
+
+
+		vm->bind(type, "print(self) -> None", // TODO: remove this later
+				 [](VM *vm, ArgsView args)
+				 {
+					 PyDeque &self = _CAST(PyDeque &, args[0]);
+					 self.print(vm);
+					 return vm->None;
+				 });
+
+		vm->bind(type, "clear(self) -> None",
+				 [](VM *vm, ArgsView args)
+				 {
+					 PyDeque &self = _CAST(PyDeque &, args[0]);
+					 self.clear();
+					 return vm->None;
+				 });
+	}
+
+	void PyDeque::_gc_mark() const
+	{
+		// TODO: implement
+	}
+	void PyDeque::appendLeft(int item) // TODO: change to PyObject*
+	{
+		DequeNode *node = new DequeNode(item);
+		this->dequeItems->push_front(node);
+	}
+	void PyDeque::append(int item) // TODO: change to PyObject*
+	{
+		// int val = _CAST(int, item);
+		DequeNode *node = new DequeNode(item);
+		this->dequeItems->push_back(node);
+	}
+
+	int PyDeque::popLeft() // TODO: change to PyObject*
+	{
+		if (this->dequeItems->empty())
+		{
+			throw std::runtime_error("pop from an empty deque");
+		}
+		DequeNode *node = this->dequeItems->pop_front();
+		return node->obj;
+	}
+
+	int PyDeque::pop() // TODO: change to PyObject*
+	{
+		if (this->dequeItems->empty())
+		{
+			throw std::runtime_error("pop from an empty deque");
+		}
+		DequeNode *node = this->dequeItems->pop_back();
+		return node->obj;
+	}
+
+	int PyDeque::count(int obj) // TODO: change to PyObject*
+	{
+		return this->dequeItems->count(obj);
+	}
+	void PyDeque::clear()
+	{
+		this->dequeItems->makeListEmpty();
+	}
+	void PyDeque::print(VM *vm)
+	{
+		// TODO: Helper function to print the deque, will be removed later
+		this->dequeItems->printList();
 	}
 
 	void PyDeque::printHelloWorld()
 	{
 		printf("Hello World!\n");
+		return;
 	}
 
 	void add_module_mycollections(VM *vm)