minor #12974 [Contributing] Fix Coding Standards example (esp. null return vs. void) (guilliamxavier)

This PR was squashed before being merged into the 3.4 branch (closes #12974).

Discussion
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[Contributing] Fix Coding Standards example (esp. null return vs. void)

Fix inconsistent return points and make the logic a bit more realistic (even if still dummy code)

Commits
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11cfb2e [Contributing] Fix Coding Standards example (esp. null return vs. void)

Author: javiereguiluz

contributing/code/standards.rst

@@ -40,6 +40,8 @@ short example containing most features described below::
 
     namespace Acme;
 
+    use Other\Qux;
+
     /**
      * Coding standards demonstration.
      */
@@ -52,12 +54,15 @@ short example containing most features described below::
          */
         private $fooBar;
 
+        private $qux;
+
         /**
          * @param string $dummy Some argument description
          */
-        public function __construct($dummy)
+        public function __construct($dummy, Qux $qux)
         {
             $this->fooBar = $this->transformText($dummy);
+            $this->qux = $qux;
         }
 
         /**
@@ -89,9 +94,9 @@ short example containing most features described below::
                 'another_default' => 'more values',
             ];
 
-            foreach ($options as $option) {
-                if (!in_array($option, $defaultOptions)) {
-                    throw new \RuntimeException(sprintf('Unrecognized option "%s"', $option));
+            foreach ($options as $name => $value) {
+                if (!array_key_exists($name, $defaultOptions)) {
+                    throw new \RuntimeException(sprintf('Unrecognized option "%s"', $name));
                 }
             }
 
@@ -101,33 +106,34 @@ short example containing most features described below::
             );
 
             if (true === $dummy) {
-                return null;
+                return 'something';
             }
 
-            if ('string' === $dummy) {
+            if (is_string($dummy)) {
                 if ('values' === $mergedOptions['some_default']) {
                     return substr($dummy, 0, 5);
                 }
 
                 return ucwords($dummy);
             }
+
+            return null;
         }
 
         /**
-         * Performs some basic check for a given value.
+         * Performs some basic operations for a given value.
          *
-         * @param mixed $value     Some value to check against
+         * @param mixed $value     Some value to operate against
          * @param bool  $theSwitch Some switch to control the method's flow
-         *
-         * @return bool|void The resultant check if $theSwitch isn't false, void otherwise
          */
-        private function reverseBoolean($value = null, $theSwitch = false)
+        private function performOperations($value = null, $theSwitch = false)
         {
             if (!$theSwitch) {
                 return;
             }
 
-            return !$value;
+            $this->qux->doFoo($value);
+            $this->qux->doBar($value);
         }
     }