fix not smart enough type checker

Author: mvorisek

src/StaticAnalysis/ExecutableLinesFindingVisitor.php

@@ -239,9 +239,12 @@ private function getLines(NodeAbstract $node, bool $fromReturns): array
         if ($node instanceof If_ ||
             $node instanceof ElseIf_ ||
             $node instanceof While_ ||
-            $node instanceof Do_ ||
-            $node instanceof Case_) {
-            if ($node instanceof Case_ && null === $node->cond) {
+            $node instanceof Do_) {
+            return [$this->getNodeStartLine($node->cond)];
+        }
+
+        if ($node instanceof Case_) {
+            if (null === $node->cond) {
                 return [];
             }