Ignore private and protected constants

CHANGELOG.rst

@@ -1,6 +1,12 @@
 Changelog
 #########
 
+1.0.1
+*****
+
+- ignore private and protected constants
+
+
 1.0.0
 *****
 

README.rst

@@ -48,6 +48,10 @@ Defining an enum class
        const SUNDAY = 6;
    }
 
+.. NOTE::
+
+   Private and protected constants are ignored.
+
 
 Supported value types
 =====================
@@ -198,7 +202,7 @@ Creating enum instances
 
    Instances created by ``fromValue()``, ``fromKey()`` and the static magic factory
    methods are cached internally and reused.
-   
+
    Multiple calls to the factory methods with the same value or key will yield
    the same instance.
 

src/Enum.php

@@ -349,8 +349,16 @@ protected static function loadValueToKeyMap()
      */
     protected static function determineKeyToValueMap(): array
     {
-        // use all constants of current class
-        return (new \ReflectionClass(static::class))->getConstants();
+        // use all public constants of current class
+        $keyToValueMap = [];
+
+        foreach ((new \ReflectionClass(static::class))->getReflectionConstants() as $constant) {
+            if ($constant->isPublic()) {
+                $keyToValueMap[$constant->name] = $constant->getValue();
+            }
+        }
+
+        return $keyToValueMap;
     }
 
     /**

tests/TestSubject/TestEnum.php

@@ -16,4 +16,7 @@ class TestEnum extends Enum
     const LOREM = 'foo';
     const IPSUM = 123;
     const DOLOR = null;
+
+    protected const SIT = 'protected const should be ignored';
+    private const AMET = 'private const should be ignored';
 }