Add initial support for chained exception inspection

src/Whoops/Exception/Inspector.php

@@ -21,6 +21,11 @@ class Inspector
      */
     private $frames;
 
+    /**
+     * @var Whoops\Exception\Inspector
+     */
+    private $previousExceptionInspector;
+
     /**
      * @param Exception $exception The exception to inspect
      */
@@ -53,6 +58,33 @@ class Inspector
         return $this->exception->getMessage();
     }
 
+    /**
+     * Does this Exception have a previous Exception?
+     * @return bool
+     */
+    public function hasPreviousException()
+    {
+        return !!$this->previousExceptionInspector || !!$this->exception->getPrevious();
+    }
+    
+    /**
+     * Returns an inspector for a previous inspector, if any.
+     * @todo   Clean this up a bit, cache stuff a bit better.
+     * @return Whoops\Exception\Inspector|null
+     */
+    public function getPreviousExceptionInspector()
+    {
+        if($this->previousExceptionInspector === null) {
+            $previousException = $this->exception->getPrevious();
+
+            if($previousException) {
+                $this->previousExceptionInspector = new Inspector($previousException);
+            }
+        }
+
+        return $this->previousExceptionInspector;
+    }
+
     /**
      * Returns an iterator for the inspected exception's
      * frames.

tests/Whoops/Exception/InspectorTest.php

@@ -7,19 +7,19 @@
 namespace Whoops\Exception;
 use Whoops\Exception\Inspector;
 use Whoops\TestCase;
-use RuntimeException;
 use Exception;
-use Mockery as m;
 
 class InspectorTest extends TestCase
 {
     /**
-     * @param string $message
+     * @param string    $message
+     * @param int       $code
+     * @param Exception $previous
      * @return Exception
      */
-    protected function getException($message = null)
+    protected function getException($message = null, $code = 0, Exception $previous = null)
     {
-        return m::mock('Exception', array($message));
+        return new Exception($message, $code, $previous);
     }
 
     /**
@@ -64,4 +64,29 @@ class InspectorTest extends TestCase
 
         $this->assertInstanceOf('Whoops\\Exception\\FrameCollection', $inspector->getFrames());
     }
+
+    /**
+     * @covers Whoops\Exception\Inspector::hasPreviousException
+     * @covers Whoops\Exception\Inspector::getPreviousExceptionInspector
+     */
+    public function testPreviousException()
+    {
+        $previousException = $this->getException("I'm here first!");
+        $exception         = $this->getException("Oh boy", null, $previousException);
+        $inspector         = $this->getInspectorInstance($exception);
+
+        $this->assertTrue($inspector->hasPreviousException());
+        $this->assertEquals($previousException, $inspector->getPreviousExceptionInspector()->getException());
+    }
+
+    /**
+     * @covers Whoops\Exception\Inspector::hasPreviousException
+     */
+    public function testNegativeHasPreviousException()
+    {
+        $exception         = $this->getException("Oh boy");
+        $inspector         = $this->getInspectorInstance($exception);
+
+        $this->assertFalse($inspector->hasPreviousException());
+    }
 }