diff --git a/_config/tests.yml b/_config/tests.yml
index 91f3a6a60..439f76a2e 100644
--- a/_config/tests.yml
+++ b/_config/tests.yml
@@ -2,18 +2,19 @@
 Name: sapphiretest
 ---
 SilverStripe\Core\Injector\Injector:
-  SilverStripe\Dev\SapphireTestState:
+  SilverStripe\Dev\State\SapphireTestState:
     properties:
       States:
-        extensions: %$SilverStripe\Dev\ExtensionTestState
-        flushable: %$SilverStripe\Dev\FlushableTestState
+        globals: %$SilverStripe\Dev\State\GlobalsTestState
+        extensions: %$SilverStripe\Dev\State\ExtensionTestState
+        flushable: %$SilverStripe\Dev\State\FlushableTestState
         requirements: %$SilverStripe\View\Dev\RequirementsTestState
 ---
 Name: kerneltest
 Before: '*'
 ---
 SilverStripe\Core\Injector\Injector:
-  SilverStripe\Dev\SapphireTestState:
+  SilverStripe\Dev\State\SapphireTestState:
     properties:
       States:
-        kernel: %$SilverStripe\Dev\KernelTestState
+        kernel: %$SilverStripe\Dev\State\KernelTestState
diff --git a/src/Control/Director.php b/src/Control/Director.php
index e7dbf651c..d0768d18d 100644
--- a/src/Control/Director.php
+++ b/src/Control/Director.php
@@ -176,6 +176,49 @@ class Director implements TemplateGlobalProvider
         $headers = array(),
         $cookies = array(),
         &$request = null
+    ) {
+        return static::mockRequest(
+            function (HTTPRequest $request) {
+                return static::direct($request);
+            },
+            $url,
+            $postVars,
+            $session,
+            $httpMethod,
+            $body,
+            $headers,
+            $cookies,
+            $request
+        );
+    }
+
+    /**
+     * Mock a request, passing this to the given callback, before resetting.
+     *
+     * @param callable $callback Action to pass the HTTPRequst object
+     * @param string $url The URL to build
+     * @param array $postVars The $_POST & $_FILES variables.
+     * @param array|Session $session The {@link Session} object representing the current session.
+     * By passing the same object to multiple  calls of Director::test(), you can simulate a persisted
+     * session.
+     * @param string $httpMethod The HTTP method, such as GET or POST.  It will default to POST if
+     * postVars is set, GET otherwise. Overwritten by $postVars['_method'] if present.
+     * @param string $body The HTTP body.
+     * @param array $headers HTTP headers with key-value pairs.
+     * @param array|Cookie_Backend $cookies to populate $_COOKIE.
+     * @param HTTPRequest $request The {@see SS_HTTP_Request} object generated as a part of this request.
+     * @return mixed Result of callback
+     */
+    public static function mockRequest(
+        $callback,
+        $url,
+        $postVars = [],
+        $session = [],
+        $httpMethod = null,
+        $body = null,
+        $headers = [],
+        $cookies = [],
+        &$request = null
     ) {
         // Build list of cleanup promises
         $finally = [];
@@ -261,6 +304,7 @@ class Director implements TemplateGlobalProvider
             $newVars['_GET'] = [];
         }
         $newVars['_SERVER']['REQUEST_URI'] = Director::baseURL() . $url;
+        $newVars['_REQUEST'] = array_merge($newVars['_GET'], $newVars['_POST']);
 
         // Create new request
         $request = HTTPRequest::createFromVariables($newVars, $body);
@@ -275,7 +319,7 @@ class Director implements TemplateGlobalProvider
 
         try {
             // Normal request handling
-            return static::direct($request);
+            return call_user_func($callback, $request);
         } finally {
             // Restore state in reverse order to assignment
             foreach (array_reverse($finally) as $callback) {
diff --git a/src/Core/CoreKernel.php b/src/Core/CoreKernel.php
index 8fbae8bb3..7b73fb7b4 100644
--- a/src/Core/CoreKernel.php
+++ b/src/Core/CoreKernel.php
@@ -132,7 +132,7 @@ class CoreKernel implements Kernel
 
     public function setEnvironment($environment)
     {
-        if (!in_array($environment, [self::DEV, self::TEST, self::LIVE])) {
+        if (!in_array($environment, [self::DEV, self::TEST, self::LIVE, null])) {
             throw new InvalidArgumentException(
                 "Director::set_environment_type passed '$environment'.  It should be passed dev, test, or live"
             );
diff --git a/src/Dev/FunctionalTest.php b/src/Dev/FunctionalTest.php
index d27193896..8e7cd4d7c 100644
--- a/src/Dev/FunctionalTest.php
+++ b/src/Dev/FunctionalTest.php
@@ -85,12 +85,13 @@ class FunctionalTest extends SapphireTest
 
     protected function setUp()
     {
+        parent::setUp();
+
         // Skip calling FunctionalTest directly.
         if (static::class == __CLASS__) {
             $this->markTestSkipped(sprintf('Skipping %s ', static::class));
         }
 
-        parent::setUp();
         $this->mainSession = new TestSession();
 
         // Disable theme, if necessary
@@ -115,9 +116,8 @@ class FunctionalTest extends SapphireTest
     protected function tearDown()
     {
         SecurityToken::enable();
-
-        parent::tearDown();
         unset($this->mainSession);
+        parent::tearDown();
     }
 
     /**
diff --git a/src/Dev/SapphireTest.php b/src/Dev/SapphireTest.php
index 957eabac5..5e796fa41 100644
--- a/src/Dev/SapphireTest.php
+++ b/src/Dev/SapphireTest.php
@@ -20,6 +20,8 @@ use SilverStripe\Core\Injector\Injector;
 use SilverStripe\Core\Injector\InjectorLoader;
 use SilverStripe\Core\Manifest\ClassLoader;
 use SilverStripe\Core\TestKernel;
+use SilverStripe\Dev\State\SapphireTestState;
+use SilverStripe\Dev\State\TestState;
 use SilverStripe\i18n\i18n;
 use SilverStripe\ORM\DataExtension;
 use SilverStripe\ORM\DataObject;
diff --git a/src/Dev/ExtensionTestState.php b/src/Dev/State/ExtensionTestState.php
similarity index 93%
rename from src/Dev/ExtensionTestState.php
rename to src/Dev/State/ExtensionTestState.php
index eefe8d484..cf3fca16f 100644
--- a/src/Dev/ExtensionTestState.php
+++ b/src/Dev/State/ExtensionTestState.php
@@ -1,10 +1,12 @@
 <?php
 
-namespace SilverStripe\Dev;
+namespace SilverStripe\Dev\State;
 
 use LogicException;
 use SilverStripe\Core\Extension;
 use SilverStripe\Core\Injector\Injector;
+use SilverStripe\Dev\Debug;
+use SilverStripe\Dev\SapphireTest;
 use SilverStripe\ORM\DataObject;
 
 /**
@@ -38,7 +40,9 @@ class ExtensionTestState implements TestState
     public function setUpOnce($class)
     {
         // May be altered by another class
-        $isAltered = $this->extensionsToReapply || $this->extensionsToRemove;
+        $isAltered = false;
+        $this->extensionsToReapply = [];
+        $this->extensionsToRemove = [];
 
         /** @var string|SapphireTest $class */
         /** @var string|DataObject $dataClass */
@@ -68,7 +72,6 @@ class ExtensionTestState implements TestState
             if (!class_exists($dataClass)) {
                 throw new LogicException("Test {$class} requires dataClass {$dataClass} which doesn't exist");
             }
-            $this->extensionsToRemove[$dataClass] = array();
             foreach ($extensions as $extension) {
                 $extension = Extension::get_classname_without_arguments($extension);
                 if (!class_exists($extension)) {
@@ -76,7 +79,7 @@ class ExtensionTestState implements TestState
                 }
                 if (!$dataClass::has_extension($extension)) {
                     if (!isset($this->extensionsToRemove[$dataClass])) {
-                        $this->extensionsToReapply[$dataClass] = [];
+                        $this->extensionsToRemove[$dataClass] = [];
                     }
                     $this->extensionsToRemove[$dataClass][] = $extension;
                     $dataClass::add_extension($extension);
diff --git a/src/Dev/FlushableTestState.php b/src/Dev/State/FlushableTestState.php
similarity index 93%
rename from src/Dev/FlushableTestState.php
rename to src/Dev/State/FlushableTestState.php
index f1eaaaf2c..23ed07f3f 100644
--- a/src/Dev/FlushableTestState.php
+++ b/src/Dev/State/FlushableTestState.php
@@ -1,10 +1,11 @@
 <?php
 
-namespace SilverStripe\Dev;
+namespace SilverStripe\Dev\State;
 
 use SilverStripe\Core\ClassInfo;
 use SilverStripe\Core\Flushable;
 use SilverStripe\Core\Resettable;
+use SilverStripe\Dev\SapphireTest;
 
 /**
  * Clears flushable / resettable objects
diff --git a/src/Dev/State/GlobalsTestState.php b/src/Dev/State/GlobalsTestState.php
new file mode 100644
index 000000000..df94e7842
--- /dev/null
+++ b/src/Dev/State/GlobalsTestState.php
@@ -0,0 +1,44 @@
+<?php
+
+namespace SilverStripe\Dev\State;
+
+use SilverStripe\Control\Director;
+use SilverStripe\Dev\SapphireTest;
+
+/**
+ * Cleans up and reset global env vars between tests
+ */
+class GlobalsTestState implements TestState
+{
+    /**
+     * Var backed up for the class
+     * @var array
+     */
+    protected $staticVars = [];
+
+    /**
+     * Vars backed up for the test
+     * @var array
+     */
+    protected $vars = [];
+
+    public function setUp(SapphireTest $test)
+    {
+        $this->vars = Director::envToVars();
+    }
+
+    public function tearDown(SapphireTest $test)
+    {
+        Director::varsToEnv($this->vars);
+    }
+
+    public function setUpOnce($class)
+    {
+        $this->staticVars = Director::envToVars();
+    }
+
+    public function tearDownOnce($class)
+    {
+        Director::varsToEnv($this->staticVars);
+    }
+}
diff --git a/src/Dev/KernelTestState.php b/src/Dev/State/KernelTestState.php
similarity index 96%
rename from src/Dev/KernelTestState.php
rename to src/Dev/State/KernelTestState.php
index e8e7c2e45..14e78aa61 100644
--- a/src/Dev/KernelTestState.php
+++ b/src/Dev/State/KernelTestState.php
@@ -1,10 +1,11 @@
 <?php
 
-namespace SilverStripe\Dev;
+namespace SilverStripe\Dev\State;
 
 use SilverStripe\Core\Injector\Injector;
 use SilverStripe\Core\Kernel;
 use SilverStripe\Core\TestKernel;
+use SilverStripe\Dev\SapphireTest;
 
 /**
  * Handles nesting of kernel before / after tests
diff --git a/src/Dev/SapphireTestState.php b/src/Dev/State/SapphireTestState.php
similarity index 93%
rename from src/Dev/SapphireTestState.php
rename to src/Dev/State/SapphireTestState.php
index 5fa8cead1..ba2bd2556 100644
--- a/src/Dev/SapphireTestState.php
+++ b/src/Dev/State/SapphireTestState.php
@@ -1,8 +1,10 @@
 <?php
 
-namespace SilverStripe\Dev;
+namespace SilverStripe\Dev\State;
 
 use SilverStripe\Core\Injector\Injectable;
+use SilverStripe\Dev\Debug;
+use SilverStripe\Dev\SapphireTest;
 
 class SapphireTestState implements TestState
 {
diff --git a/src/Dev/TestState.php b/src/Dev/State/TestState.php
similarity index 88%
rename from src/Dev/TestState.php
rename to src/Dev/State/TestState.php
index 72ea0f0d8..1f3807e4b 100644
--- a/src/Dev/TestState.php
+++ b/src/Dev/State/TestState.php
@@ -1,6 +1,9 @@
 <?php
 
-namespace SilverStripe\Dev;
+namespace SilverStripe\Dev\State;
+
+use SilverStripe\Dev\SapphireTest;
+use SilverStripe\Dev\TestOnly;
 
 /**
  * Helper for resetting, booting, or cleaning up test state.
diff --git a/src/View/Dev/RequirementsTestState.php b/src/View/Dev/RequirementsTestState.php
index d10dd2505..4e4f78c8e 100644
--- a/src/View/Dev/RequirementsTestState.php
+++ b/src/View/Dev/RequirementsTestState.php
@@ -4,7 +4,7 @@
 namespace SilverStripe\View\Dev;
 
 use SilverStripe\Dev\SapphireTest;
-use SilverStripe\Dev\TestState;
+use SilverStripe\Dev\State\TestState;
 use SilverStripe\View\Requirements;
 use SilverStripe\View\Requirements_Backend;
 
diff --git a/tests/php/Control/ControllerTest.php b/tests/php/Control/ControllerTest.php
index 8c426669a..66bd13a89 100644
--- a/tests/php/Control/ControllerTest.php
+++ b/tests/php/Control/ControllerTest.php
@@ -5,7 +5,6 @@ namespace SilverStripe\Control\Tests;
 use InvalidArgumentException;
 use SilverStripe\Control\Controller;
 use SilverStripe\Control\Director;
-use SilverStripe\Control\HTTPRequest;
 use SilverStripe\Control\Tests\ControllerTest\AccessBaseController;
 use SilverStripe\Control\Tests\ControllerTest\AccessSecuredController;
 use SilverStripe\Control\Tests\ControllerTest\AccessWildcardSecuredController;
@@ -522,22 +521,12 @@ class ControllerTest extends FunctionalTest
 
     public function testSubActions()
     {
-        /* If a controller action returns another controller, ensure that the $action variable is correctly forwarded */
+        // If a controller action returns another controller, ensure that the $action variable is correctly forwarded
         $response = $this->get("ContainerController/subcontroller/subaction");
         $this->assertEquals('subaction', $response->getBody());
 
-        $request = new HTTPRequest(
-            'GET',
-            'ContainerController/subcontroller/substring/subvieweraction'
-        );
-        /* Shift to emulate the director selecting the controller */
-        $request->shift();
-        /* Handle the request to create conditions where improperly passing the action to the viewer might fail */
-        $controller = new ControllerTest\ContainerController();
-        try {
-            $controller->handleRequest($request);
-        } catch (ControllerTest\SubController_Exception $e) {
-            $this->fail($e->getMessage());
-        }
+        // Handle nested action
+        $response = $this->get('ContainerController/subcontroller/substring/subvieweraction');
+        $this->assertEquals('Hope this works', $response->getBody());
     }
 }
diff --git a/tests/php/Control/ControllerTest/SubController.php b/tests/php/Control/ControllerTest/SubController.php
index 8b87d1d02..001dd53dd 100644
--- a/tests/php/Control/ControllerTest/SubController.php
+++ b/tests/php/Control/ControllerTest/SubController.php
@@ -34,10 +34,6 @@ class SubController extends Controller implements TestOnly
 
     public function subvieweraction()
     {
-        return $this->customise(
-            array(
-            'Thoughts' => 'Hope this works',
-            )
-        );
+        return 'Hope this works';
     }
 }
diff --git a/tests/php/Control/DirectorTest.php b/tests/php/Control/DirectorTest.php
index c7afcb0e8..e3c1e81fe 100644
--- a/tests/php/Control/DirectorTest.php
+++ b/tests/php/Control/DirectorTest.php
@@ -3,31 +3,21 @@
 namespace SilverStripe\Control\Tests;
 
 use SilverStripe\Control\Cookie_Backend;
+use SilverStripe\Control\Director;
 use SilverStripe\Control\HTTPRequest;
 use SilverStripe\Control\HTTPResponse;
 use SilverStripe\Control\HTTPResponse_Exception;
-use SilverStripe\Control\Tests\DirectorTest\TestController;
-use SilverStripe\Core\Config\Config;
-use SilverStripe\Core\Injector\Injector;
-use SilverStripe\Dev\SapphireTest;
-use SilverStripe\Control\Director;
 use SilverStripe\Control\RequestProcessor;
-use SilverStripe\Security\Security;
+use SilverStripe\Control\Tests\DirectorTest\TestController;
+use SilverStripe\Core\Injector\Injector;
+use SilverStripe\Core\Kernel;
+use SilverStripe\Dev\SapphireTest;
 
 /**
  * @todo test Director::alternateBaseFolder()
  */
 class DirectorTest extends SapphireTest
 {
-
-    protected static $originalRequestURI;
-
-    protected $originalProtocolHeaders = array();
-
-    protected $originalGet = array();
-
-    protected $originalSession = array();
-
     protected static $extra_controllers = [
         TestController::class,
     ];
@@ -35,28 +25,8 @@ class DirectorTest extends SapphireTest
     protected function setUp()
     {
         parent::setUp();
-
-        // Hold the original request URI once so it doesn't get overwritten
-        if (!self::$originalRequestURI) {
-            self::$originalRequestURI = $_SERVER['REQUEST_URI'];
-        }
-        $_SERVER['REQUEST_URI'] = 'http://www.mysite.com';
-
-        $this->originalGet = $_GET;
-        $this->originalSession = $_SESSION;
-        $_SESSION = array();
-
-        $headers = array(
-            'HTTP_X_FORWARDED_PROTOCOL', 'HTTPS', 'SSL'
-        );
-
-        foreach ($headers as $header) {
-            if (isset($_SERVER[$header])) {
-                $this->originalProtocolHeaders[$header] = $_SERVER[$header];
-            }
-        }
-
-        Config::modify()->set(Director::class, 'alternate_base_url', '/');
+        Director::config()->set('alternate_base_url', 'http://www.mysite.com/');
+        $this->expectedRedirect = null;
     }
 
     protected function getExtraRoutes()
@@ -77,24 +47,6 @@ class DirectorTest extends SapphireTest
         Director::config()->set('rules', $this->getExtraRoutes());
     }
 
-    protected function tearDown()
-    {
-        $_GET = $this->originalGet;
-        $_SESSION = $this->originalSession;
-
-        // Reinstate the original REQUEST_URI after it was modified by some tests
-        $_SERVER['REQUEST_URI'] = self::$originalRequestURI;
-
-        if ($this->originalProtocolHeaders) {
-            foreach ($this->originalProtocolHeaders as $header => $value) {
-                $_SERVER[$header] = $value;
-            }
-        }
-
-
-        parent::tearDown();
-    }
-
     public function testFileExists()
     {
         $tempFileName = 'DirectorTest_testFileExists.tmp';
@@ -118,55 +70,53 @@ class DirectorTest extends SapphireTest
 
     public function testAbsoluteURL()
     {
-
-        $rootURL = Director::protocolAndHost();
-        $_SERVER['REQUEST_URI'] = "$rootURL/mysite/sub-page/";
-        Director::config()->set('alternate_base_url', '/mysite/');
+        Director::config()->set('alternate_base_url', 'http://www.mysite.com/mysite/');
+        $_SERVER['REQUEST_URI'] = "http://www.mysite.com/mysite/sub-page/";
 
         //test empty / local urls
         foreach (array('', './', '.') as $url) {
-            $this->assertEquals("$rootURL/mysite/", Director::absoluteURL($url, Director::BASE));
-            $this->assertEquals("$rootURL/", Director::absoluteURL($url, Director::ROOT));
-            $this->assertEquals("$rootURL/mysite/sub-page/", Director::absoluteURL($url, Director::REQUEST));
+            $this->assertEquals("http://www.mysite.com/mysite/", Director::absoluteURL($url, Director::BASE));
+            $this->assertEquals("http://www.mysite.com/", Director::absoluteURL($url, Director::ROOT));
+            $this->assertEquals("http://www.mysite.com/mysite/sub-page/", Director::absoluteURL($url, Director::REQUEST));
         }
 
         // Test site root url
-        $this->assertEquals("$rootURL/", Director::absoluteURL('/'));
+        $this->assertEquals("http://www.mysite.com/", Director::absoluteURL('/'));
 
         // Test Director::BASE
-        $this->assertEquals($rootURL, Director::absoluteURL($rootURL, Director::BASE));
+        $this->assertEquals('http://www.mysite.com/', Director::absoluteURL('http://www.mysite.com/', Director::BASE));
         $this->assertEquals('http://www.mytest.com', Director::absoluteURL('http://www.mytest.com', Director::BASE));
-        $this->assertEquals("$rootURL/test", Director::absoluteURL("$rootURL/test", Director::BASE));
-        $this->assertEquals("$rootURL/root", Director::absoluteURL("/root", Director::BASE));
-        $this->assertEquals("$rootURL/root/url", Director::absoluteURL("/root/url", Director::BASE));
+        $this->assertEquals("http://www.mysite.com/test", Director::absoluteURL("http://www.mysite.com/test", Director::BASE));
+        $this->assertEquals("http://www.mysite.com/root", Director::absoluteURL("/root", Director::BASE));
+        $this->assertEquals("http://www.mysite.com/root/url", Director::absoluteURL("/root/url", Director::BASE));
 
         // Test Director::ROOT
-        $this->assertEquals($rootURL, Director::absoluteURL($rootURL, Director::ROOT));
+        $this->assertEquals('http://www.mysite.com/', Director::absoluteURL('http://www.mysite.com/', Director::ROOT));
         $this->assertEquals('http://www.mytest.com', Director::absoluteURL('http://www.mytest.com', Director::ROOT));
-        $this->assertEquals("$rootURL/test", Director::absoluteURL("$rootURL/test", Director::ROOT));
-        $this->assertEquals("$rootURL/root", Director::absoluteURL("/root", Director::ROOT));
-        $this->assertEquals("$rootURL/root/url", Director::absoluteURL("/root/url", Director::ROOT));
+        $this->assertEquals("http://www.mysite.com/test", Director::absoluteURL("http://www.mysite.com/test", Director::ROOT));
+        $this->assertEquals("http://www.mysite.com/root", Director::absoluteURL("/root", Director::ROOT));
+        $this->assertEquals("http://www.mysite.com/root/url", Director::absoluteURL("/root/url", Director::ROOT));
 
         // Test Director::REQUEST
-        $this->assertEquals($rootURL, Director::absoluteURL($rootURL, Director::REQUEST));
+        $this->assertEquals('http://www.mysite.com/', Director::absoluteURL('http://www.mysite.com/', Director::REQUEST));
         $this->assertEquals('http://www.mytest.com', Director::absoluteURL('http://www.mytest.com', Director::REQUEST));
-        $this->assertEquals("$rootURL/test", Director::absoluteURL("$rootURL/test", Director::REQUEST));
-        $this->assertEquals("$rootURL/root", Director::absoluteURL("/root", Director::REQUEST));
-        $this->assertEquals("$rootURL/root/url", Director::absoluteURL("/root/url", Director::REQUEST));
+        $this->assertEquals("http://www.mysite.com/test", Director::absoluteURL("http://www.mysite.com/test", Director::REQUEST));
+        $this->assertEquals("http://www.mysite.com/root", Director::absoluteURL("/root", Director::REQUEST));
+        $this->assertEquals("http://www.mysite.com/root/url", Director::absoluteURL("/root/url", Director::REQUEST));
 
         // Test evaluating relative urls relative to base (default)
-        $this->assertEquals("$rootURL/mysite/test", Director::absoluteURL("test"));
-        $this->assertEquals("$rootURL/mysite/test/url", Director::absoluteURL("test/url"));
-        $this->assertEquals("$rootURL/mysite/test", Director::absoluteURL("test", Director::BASE));
-        $this->assertEquals("$rootURL/mysite/test/url", Director::absoluteURL("test/url", Director::BASE));
+        $this->assertEquals("http://www.mysite.com/mysite/test", Director::absoluteURL("test"));
+        $this->assertEquals("http://www.mysite.com/mysite/test/url", Director::absoluteURL("test/url"));
+        $this->assertEquals("http://www.mysite.com/mysite/test", Director::absoluteURL("test", Director::BASE));
+        $this->assertEquals("http://www.mysite.com/mysite/test/url", Director::absoluteURL("test/url", Director::BASE));
 
         // Test evaluting relative urls relative to root
-        $this->assertEquals("$rootURL/test", Director::absoluteURL("test", Director::ROOT));
-        $this->assertEquals("$rootURL/test/url", Director::absoluteURL("test/url", Director::ROOT));
+        $this->assertEquals("http://www.mysite.com/test", Director::absoluteURL("test", Director::ROOT));
+        $this->assertEquals("http://www.mysite.com/test/url", Director::absoluteURL("test/url", Director::ROOT));
 
         // Test relative to requested page
-        $this->assertEquals("$rootURL/mysite/sub-page/test", Director::absoluteURL("test", Director::REQUEST));
-        $this->assertEquals("$rootURL/mysite/sub-page/test/url", Director::absoluteURL("test/url", Director::REQUEST));
+        $this->assertEquals("http://www.mysite.com/mysite/sub-page/test", Director::absoluteURL("test", Director::REQUEST));
+        $this->assertEquals("http://www.mysite.com/mysite/sub-page/test/url", Director::absoluteURL("test/url", Director::REQUEST));
 
         // Test that javascript links are not left intact
         $this->assertStringStartsNotWith('javascript', Director::absoluteURL('javascript:alert("attack")'));
@@ -177,17 +127,15 @@ class DirectorTest extends SapphireTest
 
     public function testAlternativeBaseURL()
     {
-        // Get original protocol and hostname
-        $rootURL = Director::protocolAndHost();
-
         // relative base URLs - you should end them in a /
         Director::config()->set('alternate_base_url', '/relativebase/');
-        $_SERVER['REQUEST_URI'] = "$rootURL/relativebase/sub-page/";
+        $_SERVER['HTTP_HOST'] = 'www.somesite.com';
+        $_SERVER['REQUEST_URI'] = "/relativebase/sub-page/";
 
         $this->assertEquals('/relativebase/', Director::baseURL());
-        $this->assertEquals($rootURL . '/relativebase/', Director::absoluteBaseURL());
+        $this->assertEquals('http://www.somesite.com/relativebase/', Director::absoluteBaseURL());
         $this->assertEquals(
-            $rootURL . '/relativebase/subfolder/test',
+            'http://www.somesite.com/relativebase/subfolder/test',
             Director::absoluteURL('subfolder/test')
         );
 
@@ -336,6 +284,10 @@ class DirectorTest extends SapphireTest
         unset($_GET['isTest']);
         unset($_GET['isDev']);
 
+        /** @var Kernel $kernel */
+        $kernel = Injector::inst()->get(Kernel::class);
+        $kernel->setEnvironment(null);
+
         // Test isDev=1
         $_GET['isDev'] = '1';
         $this->assertTrue(Director::isDev());
@@ -399,28 +351,40 @@ class DirectorTest extends SapphireTest
         );
     }
 
-    public function testTestRequestCarriesGlobals()
+    public function providerTestTestRequestCarriesGlobals()
     {
-        $fixture = array('somekey' => 'sometestvalue');
+        $tests = [];
+        $fixture = [ 'somekey' => 'sometestvalue' ];
         foreach (array('get', 'post') as $method) {
             foreach (array('return%sValue', 'returnRequestValue', 'returnCookieValue') as $testfunction) {
                 $url = 'TestController/' . sprintf($testfunction, ucfirst($method))
                     . '?' . http_build_query($fixture);
-
-                $getresponse = Director::test(
-                    $url,
-                    $fixture,
-                    null,
-                    strtoupper($method),
-                    null,
-                    null,
-                    Injector::inst()->createWithArgs(Cookie_Backend::class, array($fixture))
-                );
-
-                $this->assertInstanceOf(HTTPResponse::class, $getresponse, 'Director::test() returns HTTPResponse');
-                $this->assertEquals($fixture['somekey'], $getresponse->getBody(), 'Director::test() ' . $testfunction);
+                $tests[] = [$url, $fixture, $method];
             }
         }
+        return $tests;
+    }
+
+    /**
+     * @dataProvider providerTestTestRequestCarriesGlobals
+     * @param $url
+     * @param $fixture
+     * @param $method
+     */
+    public function testTestRequestCarriesGlobals($url, $fixture, $method)
+    {
+        $getresponse = Director::test(
+            $url,
+            $fixture,
+            null,
+            strtoupper($method),
+            null,
+            null,
+            Injector::inst()->createWithArgs(Cookie_Backend::class, array($fixture))
+        );
+
+        $this->assertInstanceOf(HTTPResponse::class, $getresponse, 'Director::test() returns HTTPResponse');
+        $this->assertEquals($fixture['somekey'], $getresponse->getBody(), "Director::test({$url}, {$method})");
     }
 
     /**
@@ -446,46 +410,87 @@ class DirectorTest extends SapphireTest
 
     public function testForceSSLProtectsEntireSite()
     {
-        $_SERVER['REQUEST_URI'] = '/admin';
-        $output = Director::forceSSL();
-        $this->assertEquals($output, 'https://' . $_SERVER['HTTP_HOST'] . $_SERVER['REQUEST_URI']);
-
-        $_SERVER['REQUEST_URI'] = Director::baseURL() . 'some-url';
-        $output = Director::forceSSL();
-        $this->assertEquals($output, 'https://' . $_SERVER['HTTP_HOST'] . $_SERVER['REQUEST_URI']);
+        $this->expectExceptionRedirect('https://www.mysite.com/some-url');
+        Director::mockRequest(function () {
+            Director::forceSSL();
+        }, '/some-url');
     }
 
     public function testForceSSLOnTopLevelPagePattern()
     {
-        $_SERVER['REQUEST_URI'] = Director::baseURL() . 'admin';
-        $output = Director::forceSSL(array('/^admin/'));
-        $this->assertEquals($output, 'https://' . $_SERVER['HTTP_HOST'] . $_SERVER['REQUEST_URI']);
+        // Expect admin to trigger redirect
+        $this->expectExceptionRedirect('https://www.mysite.com/admin');
+        Director::mockRequest(function () {
+            Director::forceSSL(array('/^admin/'));
+        }, '/admin');
     }
 
     public function testForceSSLOnSubPagesPattern()
     {
-        $_SERVER['REQUEST_URI'] = Director::baseURL() . Config::inst()->get(Security::class, 'login_url');
-        $output = Director::forceSSL(array('/^Security/'));
-        $this->assertEquals($output, 'https://' . $_SERVER['HTTP_HOST'] . $_SERVER['REQUEST_URI']);
+        // Expect to redirect to security login page
+        $this->expectExceptionRedirect('https://www.mysite.com/Security/login');
+        Director::mockRequest(function () {
+            Director::forceSSL(array('/^Security/'));
+        }, '/Security/login');
     }
 
     public function testForceSSLWithPatternDoesNotMatchOtherPages()
     {
-        $_SERVER['REQUEST_URI'] = Director::baseURL() . 'normal-page';
-        $output = Director::forceSSL(array('/^admin/'));
-        $this->assertFalse($output);
+        // Not on same url should not trigger redirect
+        Director::mockRequest(function () {
+            $this->assertFalse(Director::forceSSL(array('/^admin/')));
+        }, Director::baseURL() . 'normal-page');
 
-        $_SERVER['REQUEST_URI'] = Director::baseURL() . 'just-another-page/sub-url';
-        $output = Director::forceSSL(array('/^admin/', '/^Security/'));
-        $this->assertFalse($output);
+        // nested url should not triger redirect either
+        Director::mockRequest(function () {
+            $this->assertFalse(Director::forceSSL(array('/^admin/', '/^Security/')));
+        }, Director::baseURL() . 'just-another-page/sub-url');
     }
 
     public function testForceSSLAlternateDomain()
     {
-        Director::config()->set('alternate_base_url', '/');
-        $_SERVER['REQUEST_URI'] = Director::baseURL() . 'admin';
-        $output = Director::forceSSL(array('/^admin/'), 'secure.mysite.com');
-        $this->assertEquals($output, 'https://secure.mysite.com/admin');
+        // Ensure that forceSSL throws the appropriate exception
+        $this->expectExceptionRedirect('https://secure.mysite.com/admin');
+        Director::mockRequest(function (HTTPRequest $request) {
+            return Director::forceSSL(array('/^admin/'), 'secure.mysite.com');
+        }, Director::baseURL() . 'admin');
+    }
+
+    /**
+     * Set url to redirect to
+     *
+     * @var string
+     */
+    protected $expectedRedirect = null;
+
+    /**
+     * Expects this test to throw a HTTPResponse_Exception with the given redirect
+     *
+     * @param string $url
+     */
+    protected function expectExceptionRedirect($url)
+    {
+        $this->expectedRedirect = $url;
+    }
+
+    protected function runTest()
+    {
+        try {
+            $result = parent::runTest();
+            if ($this->expectedRedirect) {
+                $this->fail("Expected to redirect to {$this->expectedRedirect} but no redirect found");
+            }
+            return $result;
+        } catch (HTTPResponse_Exception $exception) {
+            // Check URL
+            if ($this->expectedRedirect) {
+                $url = $exception->getResponse()->getHeader('Location');
+                $this->assertEquals($this->expectedRedirect, $url, "Expected to redirect to {$this->expectedRedirect}");
+                return null;
+            } else {
+                throw $exception;
+            }
+        }
     }
 
     /**
@@ -614,28 +619,30 @@ class DirectorTest extends SapphireTest
         $processor = new RequestProcessor(array($filter));
 
         Injector::inst()->registerService($processor, RequestProcessor::class);
-
-        Director::test('some-dummy-url');
+        $response = Director::test('some-dummy-url');
+        $this->assertEquals(404, $response->getStatusCode());
 
         $this->assertEquals(1, $filter->preCalls);
         $this->assertEquals(1, $filter->postCalls);
 
         $filter->failPost = true;
 
-        $this->expectException(HTTPResponse_Exception::class);
-
-        Director::test('some-dummy-url');
+        $response = Director::test('some-dummy-url');
+        $this->assertEquals(500, $response->getStatusCode());
+        $this->assertEquals(_t(Director::class.'.REQUEST_ABORTED', 'Request aborted'), $response->getBody());
 
         $this->assertEquals(2, $filter->preCalls);
         $this->assertEquals(2, $filter->postCalls);
 
         $filter->failPre = true;
 
-        Director::test('some-dummy-url');
+        $response = Director::test('some-dummy-url');
+        $this->assertEquals(400, $response->getStatusCode());
+        $this->assertEquals(_t(Director::class.'.INVALID_REQUEST', 'Invalid request'), $response->getBody());
 
         $this->assertEquals(3, $filter->preCalls);
 
-        // preCall 'false' will trigger an exception and prevent post call execution
+        // preCall 'true' will trigger an exception and prevent post call execution
         $this->assertEquals(2, $filter->postCalls);
     }
 }
diff --git a/tests/php/Control/DirectorTest/TestController.php b/tests/php/Control/DirectorTest/TestController.php
index 713831d17..e3e4400be 100644
--- a/tests/php/Control/DirectorTest/TestController.php
+++ b/tests/php/Control/DirectorTest/TestController.php
@@ -26,21 +26,33 @@ class TestController extends Controller implements TestOnly
 
     public function returnGetValue($request)
     {
-        return $_GET['somekey'];
+        if (isset($_GET['somekey'])) {
+            return $_GET['somekey'];
+        }
+        return null;
     }
 
     public function returnPostValue($request)
     {
-        return $_POST['somekey'];
+        if (isset($_POST['somekey'])) {
+            return $_POST['somekey'];
+        }
+        return null;
     }
 
     public function returnRequestValue($request)
     {
-        return $_REQUEST['somekey'];
+        if (isset($_REQUEST['somekey'])) {
+            return $_REQUEST['somekey'];
+        }
+        return null;
     }
 
     public function returnCookieValue($request)
     {
-        return $_COOKIE['somekey'];
+        if (isset($_COOKIE['somekey'])) {
+            return $_COOKIE['somekey'];
+        }
+        return null;
     }
 }
diff --git a/tests/php/Control/FlushRequestFilterTest.php b/tests/php/Control/FlushRequestFilterTest.php
index c32de20db..8644cc014 100644
--- a/tests/php/Control/FlushRequestFilterTest.php
+++ b/tests/php/Control/FlushRequestFilterTest.php
@@ -13,9 +13,7 @@ class FlushRequestFilterTest extends FunctionalTest
     public function testImplementorsAreCalled()
     {
         TestFlushable::$flushed = false;
-
         $this->get('?flush=1');
-
         $this->assertTrue(TestFlushable::$flushed);
     }
 }
diff --git a/tests/php/Control/FlushRequestFilterTest/TestFlushable.php b/tests/php/Control/FlushRequestFilterTest/TestFlushable.php
index e3d68aa3b..c867696f0 100644
--- a/tests/php/Control/FlushRequestFilterTest/TestFlushable.php
+++ b/tests/php/Control/FlushRequestFilterTest/TestFlushable.php
@@ -7,7 +7,6 @@ use SilverStripe\Dev\TestOnly;
 
 class TestFlushable implements Flushable, TestOnly
 {
-
     public static $flushed = false;
 
     public static function flush()
diff --git a/tests/php/Control/SessionTest.php b/tests/php/Control/SessionTest.php
index 145e189b8..afdda1013 100644
--- a/tests/php/Control/SessionTest.php
+++ b/tests/php/Control/SessionTest.php
@@ -3,7 +3,6 @@
 namespace SilverStripe\Control\Tests;
 
 use SilverStripe\Control\Session;
-use SilverStripe\Core\Config\Config;
 use SilverStripe\Dev\SapphireTest;
 
 /**
@@ -105,14 +104,6 @@ class SessionTest extends SapphireTest
         $this->assertEquals(array('something' => array('does' => null)), $result);
     }
 
-    public function testNonStandardPath()
-    {
-        Session::config()->set('store_path', (realpath(dirname($_SERVER['DOCUMENT_ROOT']) . '/../session')));
-        $this->session->start();
-
-        $this->assertEquals(Config::inst()->get('SilverStripe\\Control\\Session', 'store_path'), '');
-    }
-
     public function testUserAgentLockout()
     {
         // Set a user agent
@@ -120,6 +111,7 @@ class SessionTest extends SapphireTest
 
         // Generate our session
         $s = new Session(array());
+        $s->init();
         $s->set('val', 123);
         $s->finalize();
 
@@ -128,6 +120,7 @@ class SessionTest extends SapphireTest
 
         // Verify the new session reset our values
         $s2 = new Session($s);
+        $s2->init();
         $this->assertNotEquals($s2->get('val'), 123);
     }
 }