added provided method evaluate_predicate_with_reasons for trait PredicateEvaluator

Author: GyulyVGC

src/internals/postfix_stack_item.rs

@@ -13,7 +13,7 @@ impl<Predicate> PostfixStackItem<'_, Predicate> {
     ) -> bool {
         match self {
             PostfixStackItem::Predicate(predicate) => {
-                evaluator.evaluate_predicate(predicate, reasons)
+                evaluator.evaluate_predicate_with_reasons(predicate, reasons)
             }
             PostfixStackItem::Result(result) => *result,
         }
@@ -34,17 +34,17 @@ mod tests {
         type Predicate = bool;
         type Reason = i32;
 
-        fn evaluate_predicate(
-            &self,
-            predicate: &Self::Predicate,
-            _reasons: &mut Vec<Self::Reason>,
-        ) -> bool {
+        fn evaluate_predicate(&self, predicate: &Self::Predicate) -> bool {
             if self.val >= 0 {
                 *predicate
             } else {
                 !*predicate
             }
         }
+
+        fn get_reason(&self, _predicate: &Self::Predicate) -> Self::Reason {
+            self.val
+        }
     }
 
     #[test]

src/traits/predicate_evaluator.rs

@@ -2,11 +2,25 @@ pub trait PredicateEvaluator {
     type Predicate;
     type Reason;
 
-    fn evaluate_predicate(
+    fn evaluate_predicate(&self, predicate: &Self::Predicate) -> bool;
+
+    fn get_reason(&self, predicate: &Self::Predicate) -> Self::Reason;
+
+    fn evaluate_predicate_with_reasons(
         &self,
         predicate: &Self::Predicate,
         reasons: &mut Vec<Self::Reason>,
-    ) -> bool;
+    ) -> bool {
+        let res = self.evaluate_predicate(predicate);
+
+        if res {
+            reasons.push(self.get_reason(predicate));
+        } else {
+            reasons.clear();
+        }
+
+        res
+    }
 }
 
 // impl PredicateEvaluator for () {

tests/postfix.rs

@@ -23,25 +23,17 @@ impl PredicateEvaluator for MyInteger {
     type Predicate = Predicate;
     type Reason = i32;
 
-    fn evaluate_predicate(
-        &self,
-        predicate: &Self::Predicate,
-        reasons: &mut Vec<Self::Reason>,
-    ) -> bool {
-        let res = match predicate.condition {
+    fn evaluate_predicate(&self, predicate: &Self::Predicate) -> bool {
+        match predicate.condition {
             PredicateCondition::Equal => self.val == predicate.val,
             PredicateCondition::NotEqual => self.val != predicate.val,
             PredicateCondition::GreaterThan => self.val > predicate.val,
             PredicateCondition::LowerThan => self.val < predicate.val,
-        };
-
-        if res {
-            reasons.push(predicate.val);
-        } else {
-            reasons.retain(|_| false);
         }
+    }
 
-        res
+    fn get_reason(&self, predicate: &Self::Predicate) -> Self::Reason {
+        predicate.val
     }
 }