Make priority clearer

Author: emyller

src/Engine/Engine.php

@@ -24,6 +24,9 @@
 
 class Engine
 {
+    private const float STRONGEST_PRIORITY = -INF;
+    private const float WEAKEST_PRIORITY = +INF;
+
     /**
      * Get the evaluation result for a given context.
      *
@@ -63,8 +66,8 @@ public static function getEvaluationResult($context): EvaluationResult
                 $evaluatedFeature = $evaluatedFeatures[$featureKey] ?? null;
                 if ($evaluatedFeature) {
                     $overrideWinsPriority =
-                        ($overrideFeature->priority ?? INF) <
-                        ($evaluatedFeature->priority ?? INF);
+                        ($overrideFeature->priority ?? self::WEAKEST_PRIORITY) <
+                        ($evaluatedFeature->priority ?? self::WEAKEST_PRIORITY);
                     if (!$overrideWinsPriority) {
                         continue;
                     }