Simplify and improve OOP scope check for nested functions

Author: Daimona

src/Standards/Squiz/Sniffs/PHP/InnerFunctionsSniff.php

@@ -11,6 +11,7 @@
 
 use PHP_CodeSniffer\Files\File;
 use PHP_CodeSniffer\Sniffs\Sniff;
+use PHP_CodeSniffer\Util\Tokens;
 
 class InnerFunctionsSniff implements Sniff
 {
@@ -45,39 +46,26 @@ public function process(File $phpcsFile, $stackPtr)
             return;
         }
 
-        $conditions = $tokens[$stackPtr]['conditions'];
+        $reversedConditions = array_reverse($tokens[$stackPtr]['conditions'], true);
 
         $outerFuncToken = null;
-        foreach ($conditions as $condToken => $condition) {
+        foreach ($reversedConditions as $condToken => $condition) {
             if ($condition === T_FUNCTION || $condition === T_CLOSURE) {
                 $outerFuncToken = $condToken;
                 break;
             }
+
+            if (\array_key_exists($condition, Tokens::$ooScopeTokens) === true) {
+                // Ignore methods in OOP structures defined within functions.
+                return;
+            }
         }
 
         if ($outerFuncToken === null) {
             // Not a nested function.
             return;
         }
 
-        $reversedConditions   = array_reverse($conditions, true);
-        $allowedOOPConditions = [
-            T_ANON_CLASS => true,
-            T_CLASS      => true,
-            T_TRAIT      => true,
-            T_INTERFACE  => true,
-        ];
-        foreach ($reversedConditions as $condToken => $condition) {
-            if ($condToken <= $outerFuncToken) {
-                break;
-            }
-
-            if (\array_key_exists($condition, $allowedOOPConditions) === true) {
-                // Ignore methods in OOP structures defined within functions.
-                return;
-            }
-        }
-
         $error = 'The use of inner functions is forbidden';
         $phpcsFile->addError($error, $stackPtr, 'NotAllowed');
 

src/Standards/Squiz/Tests/PHP/InnerFunctionsUnitTest.inc

@@ -75,4 +75,13 @@ function foo() {
             function foo();
         }
     }
+
+    // But disallow functions nested inside those methods
+    if (class_exists('NestedFunctionInMethod') === false) {
+        class NestedFunctionInMethod {
+            function foo() {
+                function innerFunction() {}
+            }
+        }
+    }
 }

src/Standards/Squiz/Tests/PHP/InnerFunctionsUnitTest.php

@@ -29,6 +29,7 @@ public function getErrorList()
             5  => 1,
             46 => 1,
             55 => 1,
+            83 => 1,
         ];
 
     }//end getErrorList()