make variable inventory slots

src/player.rs

@@ -12,6 +12,7 @@ pub struct Player {
     gold: usize,
     experience: usize,
     inventory: Vec<Potion>,
+    inventory_slots: usize,
 }
 
 impl Player {
@@ -24,6 +25,7 @@ impl Player {
             gold: 0,
             experience: 0,
             inventory: vec![],
+            inventory_slots: 2,
         }
     }
     pub fn get_name(&self) -> String {
@@ -70,7 +72,7 @@ impl Player {
     }
 
     pub fn add_to_inventory(&mut self, potion: &Potion) -> bool {
-        if self.inventory.len() < 10 {
+        if self.inventory.len() < self.inventory_slots {
             self.inventory.push(*potion);
             true
         } else {
@@ -78,8 +80,8 @@ impl Player {
         }
     }
 
-    pub fn inventory_size(&self) -> usize {
-        self.inventory.len()
+    pub fn inventory_size(&self) -> (usize, usize) {
+        (self.inventory.len(), self.inventory_slots)
     }
 
     pub fn consume_inventory(&mut self) -> usize {