Change the calculation of cyclomatic complexity

 - xor has not been covered yet.
 - The ternary operator and the coalesce operator has been count both
   as 2. Also the default case of a switch statement has been counted.
   But as the else statement is not counted because it represents the
   default path (and can be elimated), the default case should not be
   counted (corresponds to else) and both the ternary and the coalesce
   operator should be counted as 1, because they can be exchanged by
   if-else / if which would be counted as 1.
   The spaceship operator by contrast is now counted as 2, because it
   would need if-elseif-else to replace it.
 - continue does not increase the cyclomatic complexity as its no
   decision. It's the if around the continue which increases the ccn.

src/Hal/Metric/Class_/Complexity/CyclomaticComplexityVisitor.php

@@ -1,7 +1,6 @@
 <?php
 namespace Hal\Metric\Class_\Complexity;
 
-use Hal\Component\Reflected\Method;
 use Hal\Metric\Helper\MetricClassNameGenerator;
 use Hal\Metric\Metrics;
 use PhpParser\Node;
@@ -24,31 +23,22 @@
  */
 class CyclomaticComplexityVisitor extends NodeVisitorAbstract
 {
-
     /**
      * @var Metrics
      */
     private $metrics;
 
-    /**
-     * ClassEnumVisitor constructor.
-     * @param Metrics $metrics
-     */
     public function __construct(Metrics $metrics)
     {
         $this->metrics = $metrics;
     }
 
-    /**
-     * @inheritdoc
-     */
     public function leaveNode(Node $node)
     {
         if ($node instanceof Stmt\Class_
             || $node instanceof Stmt\Interface_
             || $node instanceof Stmt\Trait_
         ) {
-
             $class = $this->metrics->get(MetricClassNameGenerator::getName($node));
 
             $ccn = 1;
@@ -62,9 +52,9 @@ public function leaveNode(Node $node)
                         $ccn = 0;
 
                         foreach (get_object_vars($node) as $name => $member) {
-                            foreach (is_array($member) ? $member : [$member] as $member_item) {
-                                if ($member_item instanceof Node) {
-                                    $ccn += $cb($member_item);
+                            foreach (is_array($member) ? $member : [$member] as $memberItem) {
+                                if ($memberItem instanceof Node) {
+                                    $ccn += $cb($memberItem);
                                 }
                             }
                         }
@@ -78,18 +68,23 @@ public function leaveNode(Node $node)
                             case $node instanceof Stmt\Do_:
                             case $node instanceof Node\Expr\BinaryOp\LogicalAnd:
                             case $node instanceof Node\Expr\BinaryOp\LogicalOr:
+                            case $node instanceof Node\Expr\BinaryOp\LogicalXor:
                             case $node instanceof Node\Expr\BinaryOp\BooleanAnd:
                             case $node instanceof Node\Expr\BinaryOp\BooleanOr:
-                            case $node instanceof Node\Expr\BinaryOp\Spaceship:
-                            case $node instanceof Stmt\Case_: // include default
                             case $node instanceof Stmt\Catch_:
-                            case $node instanceof Stmt\Continue_:
-                                $ccn++;
-                                break;
                             case $node instanceof Node\Expr\Ternary:
                             case $node instanceof Node\Expr\BinaryOp\Coalesce:
-                                $ccn = $ccn + 2;
+                                $ccn++;
+                                break;
+                            case $node instanceof Stmt\Case_: // include default
+                                if ($node->cond !== null) { // exclude default
+                                    $ccn++;
+                                }
+                                break;
+                            case $node instanceof Node\Expr\BinaryOp\Spaceship:
+                                $ccn += 2;
                                 break;
+
                         }
                         return $ccn;
                     };

tests/Metric/Class_/Complexity/CyclomaticComplexityVisitorTest.php

@@ -53,17 +53,22 @@ public function testCyclomaticComplexityOfMethodsIsWellCalculated($example, $cla
     public function provideExamplesForClasses()
     {
         return [
-            [ __DIR__.'/../../examples/cyclomatic1.php', 'A', 8],
-            [ __DIR__.'/../../examples/cyclomatic1.php', 'B', 5],
-            [ __DIR__.'/../../examples/cyclomatic_anon.php', 'Foo\C', 1],
+            'A' => [ __DIR__.'/../../examples/cyclomatic1.php', 'A', 8],
+            'B' => [ __DIR__.'/../../examples/cyclomatic1.php', 'B', 4],
+            'Foo\\C' => [ __DIR__.'/../../examples/cyclomatic_anon.php', 'Foo\\C', 1],
+            'SwitchCase' => [ __DIR__.'/../../examples/cyclomatic_full.php', 'SwitchCase', 4],
+            'IfElseif' => [ __DIR__.'/../../examples/cyclomatic_full.php', 'IfElseif', 7],
+            'Loops' => [ __DIR__.'/../../examples/cyclomatic_full.php', 'Loops', 5],
+            'CatchIt' => [ __DIR__.'/../../examples/cyclomatic_full.php', 'CatchIt', 3],
+            'Logical' => [ __DIR__.'/../../examples/cyclomatic_full.php', 'Logical', 11],
         ];
     }
 
     public function provideExamplesForMethods()
     {
         return [
             [ __DIR__.'/../../examples/cyclomatic1.php', 'A', 6],
-            [ __DIR__.'/../../examples/cyclomatic1.php', 'B', 5],
+            [ __DIR__.'/../../examples/cyclomatic1.php', 'B', 4],
         ];
     }
 

tests/Metric/examples/cyclomatic_full.php

@@ -0,0 +1,72 @@
+<?php
+class SwitchCase // ccn2: 4
+{
+    function __invoke()
+    {
+        switch ('abc') {
+            case 'abc':
+            case 'def':
+            case 'hij':
+                break;
+            default:
+        }
+    }
+}
+
+class IfElseif // ccn2: 7
+{
+    function __invoke()
+    {
+        if (true) {
+            if (true) {
+            } elseif (true) {
+            } else {
+            }
+        } elseif (true) {
+            if (false) {
+            }
+        }
+
+        if (true) {
+        }
+    }
+}
+
+class Loops // ccn2: 5
+{
+    function __invoke()
+    {
+        while (true) {
+            do {
+            } while (false);
+        }
+        foreach (array() as $each) {
+            for ($i = 0; $i < 0; ++$i) {
+            }
+        }
+    }
+}
+
+class CatchIt // ccn2: 3
+{
+    function __invoke()
+    {
+        try {
+        } catch (Exception $e) {
+        } catch (Throwable $e) {
+        } finally {
+        }
+    }
+}
+
+class Logical // ccn2: 11
+{
+    function __invoke()
+    {
+        $a = (true || false) and (false && true) or (true xor false);
+        $b = $a ? 1 : 2;
+        $c = $b ?: 0;
+        $d = $b ?? $c;
+        $e = $b <=> $d;
+    }
+}