feat: Add evolution model and comprehensive tests for evolution requirements

src/models/evolution.cairo

@@ -12,15 +12,12 @@ struct Evolution {
 }
 
 mod rules {
-    /// Minimum rules for beast evolution
-
     /// Minimum level required before evolution is possible
     const LEVEL_REQUIREMENT: u32 = 10;
     /// Minimum number of battles required before evolution
     const REQUIRED_BATTLES: u32 = 5;
     /// Item ID required for evolution (special evolution stone)
     const REQUIRED_ITEM: u32 = 1001;
-
 }
 
 #[generate_trait]
@@ -49,3 +46,124 @@ impl EvolutionImpl of EvolutionTrait {
         }
     }
 }
+
+
+#[cfg(test)]
+mod tests {
+    use super::{Evolution, EvolutionTrait};
+    use core::result::Result;
+
+    #[test]
+    fn test_evolution_with_valid_requirements() {
+
+        let mut evolution = Evolution {
+            base_beast_id: 1_u32,
+            evolved_beast_id: 0_u32,
+            level_requirement: 15_u32, 
+            required_battles: 10_u32,  
+            required_item: Option::Some(1001_u32) 
+        };
+
+        let result = evolution.evolve();
+
+        match result {
+            Result::Ok(evolved_id) => {
+                assert(evolved_id == 10_u32, 'Incorrect evolution ID');
+                assert(evolution.evolved_beast_id == 10_u32, 'Beast not evolved correctly');
+            },
+            Result::Err(_) => {
+                panic!("Evolution should have succeeded")
+            }
+        }
+    }
+
+    #[test]
+    fn test_evolution_with_invalid_level() {
+
+        let mut evolution = Evolution {
+            base_beast_id: 1_u32,
+            evolved_beast_id: 0_u32,
+            level_requirement: 5_u32,
+            required_battles: 10_u32,
+            required_item: Option::Some(1001_u32)
+        };
+
+        let result = evolution.evolve();
+
+        match result {
+            Result::Ok(_) => {
+                panic!("Evolution should have failed due to low level")
+            },
+            Result::Err(e) => {
+                assert(e == 'Evolution requirements not met', 'Unexpected error message');
+            }
+        }
+    }
+
+    #[test]
+    fn test_evolution_with_invalid_battles() {
+
+        let mut evolution = Evolution {
+            base_beast_id: 1_u32,
+            evolved_beast_id: 0_u32,
+            level_requirement: 15_u32,
+            required_battles: 3_u32, 
+            required_item: Option::Some(1001_u32)
+        };
+
+        let result = evolution.evolve();
+        match result {
+            Result::Ok(_) => {
+                panic!("Evolution should have failed due to insufficient battles")
+            },
+            Result::Err(e) => {
+                assert(e == 'Evolution requirements not met', 'Unexpected error message');
+            }
+        }
+    }
+
+    #[test]
+    fn test_evolution_with_invalid_item() {
+
+        let mut evolution = Evolution {
+            base_beast_id: 1_u32,
+            evolved_beast_id: 0_u32,
+            level_requirement: 15_u32,
+            required_battles: 10_u32,
+            required_item: Option::Some(999_u32) 
+        };
+
+        let result = evolution.evolve();
+        match result {
+            Result::Ok(_) => {
+                panic!("Evolution should have failed due to wrong item")
+            },
+            Result::Err(e) => {
+                assert(e == 'Evolution requirements not met', 'Unexpected error message');
+            }
+        }
+    }
+
+    #[test]
+    fn test_evolution_with_no_item_requirement() {
+
+        let mut evolution = Evolution {
+            base_beast_id: 1_u32,
+            evolved_beast_id: 0_u32,
+            level_requirement: 15_u32,
+            required_battles: 10_u32,
+            required_item: Option::None 
+        };
+
+        let result = evolution.evolve();
+
+        match result {
+            Result::Ok(evolved_id) => {
+                assert(evolved_id == 10_u32, 'Incorrect evolution ID');
+            },
+            Result::Err(_) => {
+                panic!("Evolution should have succeeded without item requirement")
+            }
+        }
+    }
+}