Stop condition evaluation on first failure (#112)

* Stop condition evaluation on first failure

The `&=` operator will convert the value to an integer (see some examples here: https://stackoverflow.com/questions/17553004/boolean-assignment-operators-in-php) which causes the condition evaluation to not stop on the first failure, as otherwise noted.

Author: k4emic

CHANGELOG.md

@@ -10,6 +10,10 @@
 
 - Support for `nyholm/psr7` version 1.0. 
 
+### Fixed
+
+- Fixed condition evaluation
+
 ## 1.4.0 - 2018-02-06
 
 ### Added

spec/ClassDiscoverySpec.php

@@ -44,9 +44,16 @@ function it_returns_a_class()
 
     function it_validates_conditions() {
         $c0 = ['class' => 'ClassName0', 'condition' => false];
+        $c0b = ['class' => 'ClassName0', 'condition' => [false, true]];
+        $c0c = ['class' => 'ClassName0', 'condition' => [true, false]];
+        $c0d = ['class' => 'ClassName0', 'condition' => [true, false, true]];
+        $c0e = ['class' => 'ClassName0', 'condition' => [false, function() {
+            throw new \RuntimeException('This should never be called');
+        }]];
         $c1 = ['class' => 'ClassName1', 'condition' => true];
         $c2 = ['class' => 'ClassName2', 'condition' => false];
-        DiscoveryHelper::setClasses('Foobar', [$c0, $c1, $c2]);
+        $c3 = ['class' => 'ClassName3', 'condition' => true];
+        DiscoveryHelper::setClasses('Foobar', [$c0, $c0b, $c0c, $c0d, $c0e, $c1, $c2, $c3]);
 
         $this->find('Foobar')->shouldReturn('ClassName1');
     }

src/ClassDiscovery.php

@@ -167,14 +167,14 @@ protected static function evaluateCondition($condition)
         } elseif (is_bool($condition)) {
             return $condition;
         } elseif (is_array($condition)) {
-            $evaluatedCondition = true;
-
             // Immediately stop execution if the condition is false
-            for ($i = 0; $i < count($condition) && false !== $evaluatedCondition; ++$i) {
-                $evaluatedCondition &= static::evaluateCondition($condition[$i]);
+            for ($i = 0; $i < count($condition); ++$i) {
+                if (false === static::evaluateCondition($condition[$i])) {
+                    return false;
+                }
             }
 
-            return $evaluatedCondition;
+            return true;
         }
 
         return false;