From e3f3460f625f63bb8157f0dd9418a0580f12fdf1 Mon Sep 17 00:00:00 2001
From: Lisachenko Alexander <lisachenko.it@gmail.com>
Date: Sun, 9 Apr 2017 22:22:48 +0300
Subject: [PATCH] Method isSubclassOf() should also look at interfaces, fixes
 #72

---
 src/Traits/ReflectionClassLikeTrait.php | 13 ++++++++++---
 tests/ReflectionClassTest.php           | 14 ++++++++++++++
 2 files changed, 24 insertions(+), 3 deletions(-)

diff --git a/src/Traits/ReflectionClassLikeTrait.php b/src/Traits/ReflectionClassLikeTrait.php
index f2e02743..604dde2b 100644
--- a/src/Traits/ReflectionClassLikeTrait.php
+++ b/src/Traits/ReflectionClassLikeTrait.php
@@ -758,9 +758,16 @@ public function isSubclassOf($class)
 
         if (!$this->classLikeNode instanceof Class_) {
             return false;
-        } else {
-            $extends = $this->classLikeNode->extends;
-            if ($extends && $extends->toString() == $class) {
+        }
+
+        $extends = $this->classLikeNode->extends;
+        if ($extends && $extends->toString() == $class) {
+            return true;
+        }
+
+        $implementedInterfaces = $this->classLikeNode->implements;
+        foreach ($implementedInterfaces as $implementedInterface) {
+            if ($implementedInterface->toString() == $class) {
                 return true;
             }
         }
diff --git a/tests/ReflectionClassTest.php b/tests/ReflectionClassTest.php
index 5d5fc346..6fc07522 100644
--- a/tests/ReflectionClassTest.php
+++ b/tests/ReflectionClassTest.php
@@ -2,11 +2,13 @@
 namespace Go\ParserReflection;
 
 use Go\ParserReflection\Stub\ClassWithConstantsAndInheritance;
+use Go\ParserReflection\Stub\ClassWithInterface;
 use Go\ParserReflection\Stub\ClassWithMethodsAndProperties;
 use Go\ParserReflection\Stub\ClassWithScalarConstants;
 use Go\ParserReflection\Stub\FinalClass;
 use Go\ParserReflection\Stub\ImplicitAbstractClass;
 use Go\ParserReflection\Stub\SimpleAbstractInheritance;
+use Go\ParserReflection\Stub\SimpleInterface;
 
 class ReflectionClassTest extends AbstractTestCase
 {
@@ -147,6 +149,18 @@ public function testGetProperties($fileName)
         }
     }
 
+    /**
+     * Test isSubclassOf() method parity
+     */
+    public function testIsSubclassOf()
+    {
+        $parsedClass   = $this->parsedRefFileNamespace->getClass(ClassWithInterface::class);
+        $actualValue   = $parsedClass->isSubclassOf(SimpleInterface::class);
+        $originalClass = new \ReflectionClass(ClassWithInterface::class);
+        $expectedValue = $originalClass->isSubclassOf(SimpleInterface::class);
+        $this->assertSame($expectedValue, $actualValue, "Class should also check interfaces for isSubclassOf");
+    }
+
     public function testNewInstanceMethod()
     {
         $parsedRefClass = $this->parsedRefFileNamespace->getClass(FinalClass::class);