Add testcases

Author: sj-i

Zend/tests/traits/constant_017.phpt

@@ -0,0 +1,13 @@
+--TEST--
+Referencing trait constants directly on calling \defined() returns false
+--FILE--
+<?php
+
+trait TestTrait {
+  public const Constant = 42;
+}
+
+var_dump(\defined('TestTrait::Constant'));
+?>
+--EXPECTF--
+bool(false)

Zend/tests/traits/constant_018.phpt

@@ -0,0 +1,17 @@
+--TEST--
+Referencing trait constants directly on calling \constant() causes a fatal error
+--FILE--
+<?php
+
+trait TestTrait {
+  public const Constant = 42;
+}
+
+var_dump(\constant('TestTrait::Constant'));
+?>
+--EXPECTF--
+Fatal error: Uncaught Error: Cannot access trait constant TestTrait::Constant directly in %s:%d
+Stack trace:
+#0 %s: constant('TestTrait::Cons...')
+#1 {main}
+  thrown in %s on line %d