Bugfix: headers not being passed to request (#529)

* Add IDE files to gitignore

* Add failing UT to show bug

* Fix bug: reset plugin when headers change

* Remove IDEs from gitignore

Author: emmetog

Diff for: lib/Github/HttpClient/Builder.php

@@ -168,6 +168,9 @@ public function addHeaderValue($header, $headerValue)
         } else {
             $this->headers[$header] = array_merge((array)$this->headers[$header], array($headerValue));
         }
+
+        $this->removePlugin(Plugin\HeaderAppendPlugin::class);
+        $this->addPlugin(new Plugin\HeaderAppendPlugin($this->headers));
     }
 
     /**

Diff for: test/Github/Tests/HttpClient/BuilderTest.php

@@ -49,4 +49,28 @@ public function shouldAddHeaders()
 
         $client->addHeaders($headers);
     }
+
+    /**
+     * @test
+     */
+    public function appendingHeaderShouldAddAndRemovePlugin()
+    {
+        $expectedHeaders = [
+            'Accept' => 'application/vnd.github.v3',
+        ];
+
+        $client = $this->getMockBuilder(\Github\HttpClient\Builder::class)
+            ->setMethods(array('removePlugin', 'addPlugin'))
+            ->getMock();
+
+        $client->expects($this->once())
+            ->method('removePlugin')
+            ->with(Plugin\HeaderAppendPlugin::class);
+
+        $client->expects($this->once())
+            ->method('addPlugin')
+            ->with(new Plugin\HeaderAppendPlugin($expectedHeaders));
+
+        $client->addHeaderValue('Accept', 'application/vnd.github.v3');
+    }
 }