PSR12/ConstantVisibility: prevent false negatives for asym visibility

Class constants do not support asymmetric visibility, so if this "typo" would be encountered, the sniff should still flag the constant as not having visibility.

Includes test.

Author: jrfnl

src/Standards/PSR12/Sniffs/Properties/ConstantVisibilitySniff.php

@@ -50,8 +50,14 @@ public function process(File $phpcsFile, $stackPtr)
         $ignore   = Tokens::$emptyTokens;
         $ignore[] = T_FINAL;
 
+        $validVisibility = [
+            T_PRIVATE   => T_PRIVATE,
+            T_PUBLIC    => T_PUBLIC,
+            T_PROTECTED => T_PROTECTED,
+        ];
+
         $prev = $phpcsFile->findPrevious($ignore, ($stackPtr - 1), null, true);
-        if (isset(Tokens::$scopeModifiers[$tokens[$prev]['code']]) === true) {
+        if (isset($validVisibility[$tokens[$prev]['code']]) === true) {
             return;
         }
 

src/Standards/PSR12/Tests/Properties/ConstantVisibilityUnitTest.2.inc

@@ -0,0 +1,7 @@
+<?php
+
+// Intentional parse error - unsupported asym visibility used on class constant.
+// Testing that the sniff will flags this as the constant doesn't have a valid visibility.
+class Foo {
+    public(set) const BAR = 'bar';
+}

src/Standards/PSR12/Tests/Properties/ConstantVisibilityUnitTest.php

@@ -55,6 +55,11 @@ public function getWarningList($testFile='')
                 21 => 1,
             ];
 
+        case 'ConstantVisibilityUnitTest.2.inc':
+            return [
+                6 => 1,
+            ];
+
         default:
             return [];
         }