GH-15976: test current output

So that it is clearer what changes

Zend/tests/gh15976/alias-names.phpt

@@ -0,0 +1,13 @@
+--TEST--
+GH-15976: Bad class alias names
+--FILE--
+<?php
+
+class_alias( 'stdClass', '_' );
+class_alias( 'stdClass', 'bool' );
+
+?>
+--EXPECTF--
+Deprecated: Using "_" as a class name is deprecated since 8.4 in %salias-names.php on line 3
+
+Fatal error: Cannot use 'bool' as class name as it is reserved in %salias-names.php on line 4

Zend/tests/gh15976/class-names.phpt

@@ -0,0 +1,13 @@
+--TEST--
+GH-15976: Bad class names
+--FILE--
+<?php
+
+class _ {}
+class bool {}
+
+?>
+--EXPECTF--
+Deprecated: Using "_" as a class name is deprecated since 8.4 in %sclass-names.php on line 3
+
+Fatal error: Cannot use 'bool' as class name as it is reserved in %sclass-names.php on line 4

Zend/tests/gh15976/enum-names.phpt

@@ -0,0 +1,13 @@
+--TEST--
+GH-15976: Bad enum names
+--FILE--
+<?php
+
+enum _ {}
+enum bool {}
+
+?>
+--EXPECTF--
+Deprecated: Using "_" as a class name is deprecated since 8.4 in %senum-names.php on line 3
+
+Fatal error: Cannot use 'bool' as class name as it is reserved in %senum-names.php on line 4

Zend/tests/gh15976/interface-names.phpt

@@ -0,0 +1,13 @@
+--TEST--
+GH-15976: Bad interface names
+--FILE--
+<?php
+
+interface _ {}
+interface bool {}
+
+?>
+--EXPECTF--
+Deprecated: Using "_" as a class name is deprecated since 8.4 in %sinterface-names.php on line 3
+
+Fatal error: Cannot use 'bool' as class name as it is reserved in %sinterface-names.php on line 4

Zend/tests/gh15976/trait-names.phpt

@@ -0,0 +1,13 @@
+--TEST--
+GH-15976: Bad trait names
+--FILE--
+<?php
+
+trait _ {}
+trait bool {}
+
+?>
+--EXPECTF--
+Deprecated: Using "_" as a class name is deprecated since 8.4 in %strait-names.php on line 3
+
+Fatal error: Cannot use 'bool' as class name as it is reserved in %strait-names.php on line 4