diff --git a/src/League/OAuth2/Server/Grant/Password.php b/src/League/OAuth2/Server/Grant/Password.php
index 1f265081..e87da146 100644
--- a/src/League/OAuth2/Server/Grant/Password.php
+++ b/src/League/OAuth2/Server/Grant/Password.php
@@ -11,7 +11,7 @@
 
 namespace League\OAuth2\Server\Grant;
 
-use League\OAuth2\Server\Authorization;
+use League\OAuth2\Server\AuthorizationServer;
 use League\OAuth2\Server\Entity\AccessToken;
 use League\OAuth2\Server\Entity\Client;
 use League\OAuth2\Server\Entity\RefreshToken;
@@ -87,7 +87,7 @@ class Password extends AbstractGrant
         $clientId = $this->server->getRequest()->request->get('client_id', null);
         if (is_null($clientId)) {
             throw new ClientException(
-                sprintf(Authorization::getExceptionMessage('invalid_request'), 'client_id'),
+                sprintf(AuthorizationServer::getExceptionMessage('invalid_request'), 'client_id'),
                 0
             );
         }
@@ -95,7 +95,7 @@ class Password extends AbstractGrant
         $clientSecret = $this->server->getRequest()->request->get('client_secret', null);
         if (is_null($clientSecret)) {
             throw new ClientException(
-                sprintf(Authorization::getExceptionMessage('invalid_request'), 'client_secret'),
+                sprintf(AuthorizationServer::getExceptionMessage('invalid_request'), 'client_secret'),
                 0
             );
         }
@@ -109,13 +109,13 @@ class Password extends AbstractGrant
         );
 
         if (($client instanceof Client) === false) {
-            throw new ClientException(Authorization::getExceptionMessage('invalid_client'), 8);
+            throw new ClientException(AuthorizationServer::getExceptionMessage('invalid_client'), 8);
         }
 
         $username = $this->server->getRequest()->request->get('username', null);
         if (is_null($username)) {
             throw new ClientException(
-                sprintf(Authorization::getExceptionMessage('invalid_request'), 'username'),
+                sprintf(AuthorizationServer::getExceptionMessage('invalid_request'), 'username'),
                 0
             );
         }
@@ -123,7 +123,7 @@ class Password extends AbstractGrant
         $password = $this->server->getRequest()->request->get('password', null);
         if (is_null($password)) {
             throw new ClientException(
-                sprintf(Authorization::getExceptionMessage('invalid_request'), 'password'),
+                sprintf(AuthorizationServer::getExceptionMessage('invalid_request'), 'password'),
                 0
             );
         }
diff --git a/src/League/OAuth2/Server/Grant/RefreshToken.php b/src/League/OAuth2/Server/Grant/RefreshToken.php
index d1415b1a..87f2563e 100644
--- a/src/League/OAuth2/Server/Grant/RefreshToken.php
+++ b/src/League/OAuth2/Server/Grant/RefreshToken.php
@@ -12,7 +12,7 @@
 namespace League\OAuth2\Server\Grant;
 
 use League\OAuth2\Server\Request;
-use League\OAuth2\Server\Authorization;
+use League\OAuth2\Server\AuthorizationServer;
 use League\OAuth2\Server\Exception;
 use League\OAuth2\Server\Util\SecureKey;
 use League\OAuth2\Server\Storage\SessionInterface;
@@ -88,7 +88,7 @@ class RefreshToken extends AbstractGrant
         );
 
         if ($client === null) {
-            throw new ClientException(Authorization::getExceptionMessage('invalid_client'), 8);
+            throw new ClientException(AuthorizationServer::getExceptionMessage('invalid_client'), 8);
         }
 
         $oldRefreshTokenParam = $this->server->getRequest()->request->get('refresh_token', null);
@@ -122,7 +122,6 @@ class RefreshToken extends AbstractGrant
         } else {
             // The OAuth spec says that a refreshed access token can have the original scopes or fewer so ensure
             //  the request doesn't include any new scopes
-
             foreach ($requestedScopes as $requestedScope) {
                 if (!isset($scopes[$requestedScope->getId()])) {
                     throw new Exception\ClientException(
diff --git a/tests/Grant/PasswordTest.php b/tests/Grant/PasswordTest.php
new file mode 100644
index 00000000..38b33b32
--- /dev/null
+++ b/tests/Grant/PasswordTest.php
@@ -0,0 +1,474 @@
+<?php
+
+namespace LeagueTests\Grant;
+
+use League\OAuth2\Server\Grant\Password;
+use League\OAuth2\Server\Grant\RefreshToken;
+use League\OAuth2\Server\Entity\Scope;
+use League\OAuth2\Server\Entity\Client;
+use League\OAuth2\Server\AuthorizationServer;
+use League\OAuth2\Server\Grant\ClientException;
+use Mockery as M;
+
+class PasswordTest extends \PHPUnit_Framework_TestCase
+{
+    function testCompleteFlowMissingClientId()
+    {
+        $this->setExpectedException('League\OAuth2\Server\Exception\ClientException');
+
+        $_POST['grant_type'] = 'password';
+
+        $server = new AuthorizationServer;
+        $grant = new Password;
+
+        $server->addGrantType($grant);
+        $server->issueAccessToken();
+
+    }
+
+    function testCompleteFlowMissingClientSecret()
+    {
+        $this->setExpectedException('League\OAuth2\Server\Exception\ClientException');
+
+        $_POST = [
+            'grant_type' => 'password',
+            'client_id' =>  'testapp'
+        ];
+
+        $server = new AuthorizationServer;
+        $grant = new Password;
+
+        $server->addGrantType($grant);
+        $server->issueAccessToken();
+    }
+
+    function testCompleteFlowInvalidClient()
+    {
+        $this->setExpectedException('League\OAuth2\Server\Exception\ClientException');
+
+        $_POST = [
+            'grant_type' => 'password',
+            'client_id' =>  'testapp',
+            'client_secret' =>  'foobar'
+        ];
+
+        $server = new AuthorizationServer;
+        $grant = new Password;
+
+        $clientStorage = M::mock('League\OAuth2\Server\Storage\ClientInterface');
+        $clientStorage->shouldReceive('setServer');
+        $clientStorage->shouldReceive('get')->andReturn(null);
+
+        $server->setClientStorage($clientStorage);
+
+        $server->addGrantType($grant);
+        $server->issueAccessToken();
+    }
+
+    function testNoUsername()
+    {
+        $this->setExpectedException('League\OAuth2\Server\Exception\ClientException');
+
+        $_POST = [
+            'grant_type' => 'password',
+            'client_id' =>  'testapp',
+            'client_secret' =>  'foobar'
+        ];
+
+        $server = new AuthorizationServer;
+        $grant = new Password;
+
+        $clientStorage = M::mock('League\OAuth2\Server\Storage\ClientInterface');
+        $clientStorage->shouldReceive('setServer');
+        $clientStorage->shouldReceive('get')->andReturn(
+            (new Client($server))->setId('testapp')
+        );
+
+        $sessionStorage = M::mock('League\OAuth2\Server\Storage\SessionInterface');
+        $sessionStorage->shouldReceive('setServer');
+        $sessionStorage->shouldReceive('create');
+        $sessionStorage->shouldReceive('getScopes')->andReturn([]);
+
+        $accessTokenStorage = M::mock('League\OAuth2\Server\Storage\AccessTokenInterface');
+        $accessTokenStorage->shouldReceive('setServer');
+        $accessTokenStorage->shouldReceive('create');
+        $accessTokenStorage->shouldReceive('getScopes')->andReturn([]);
+
+        $scopeStorage = M::mock('League\OAuth2\Server\Storage\ScopeInterface');
+        $scopeStorage->shouldReceive('setServer');
+        $scopeStorage->shouldReceive('get')->andReturn(null);
+
+        $server->setClientStorage($clientStorage);
+        $server->setScopeStorage($scopeStorage);
+        $server->setSessionStorage($sessionStorage);
+        $server->setAccessTokenStorage($accessTokenStorage);
+
+        $server->addGrantType($grant);
+        $server->issueAccessToken();
+    }
+
+    function testNoPassword()
+    {
+        $this->setExpectedException('League\OAuth2\Server\Exception\ClientException');
+
+        $_POST = [
+            'grant_type' => 'password',
+            'client_id' =>  'testapp',
+            'client_secret' =>  'foobar',
+            'username'  =>  'foo'
+        ];
+
+        $server = new AuthorizationServer;
+        $grant = new Password;
+
+        $clientStorage = M::mock('League\OAuth2\Server\Storage\ClientInterface');
+        $clientStorage->shouldReceive('setServer');
+        $clientStorage->shouldReceive('get')->andReturn(
+            (new Client($server))->setId('testapp')
+        );
+
+        $sessionStorage = M::mock('League\OAuth2\Server\Storage\SessionInterface');
+        $sessionStorage->shouldReceive('setServer');
+        $sessionStorage->shouldReceive('create');
+        $sessionStorage->shouldReceive('getScopes')->andReturn([]);
+
+        $accessTokenStorage = M::mock('League\OAuth2\Server\Storage\AccessTokenInterface');
+        $accessTokenStorage->shouldReceive('setServer');
+        $accessTokenStorage->shouldReceive('create');
+        $accessTokenStorage->shouldReceive('getScopes')->andReturn([]);
+
+        $scopeStorage = M::mock('League\OAuth2\Server\Storage\ScopeInterface');
+        $scopeStorage->shouldReceive('setServer');
+        $scopeStorage->shouldReceive('get')->andReturn(null);
+
+        $server->setClientStorage($clientStorage);
+        $server->setScopeStorage($scopeStorage);
+        $server->setSessionStorage($sessionStorage);
+        $server->setAccessTokenStorage($accessTokenStorage);
+
+        $server->addGrantType($grant);
+        $server->issueAccessToken();
+    }
+
+    function testNoCallable()
+    {
+        $this->setExpectedException('League\OAuth2\Server\Exception\InvalidGrantTypeException');
+
+        $_POST = [
+            'grant_type' => 'password',
+            'client_id' =>  'testapp',
+            'client_secret' =>  'foobar',
+            'username'  =>  'foo',
+            'password'  =>  'foobar'
+        ];
+
+        $server = new AuthorizationServer;
+        $grant = new Password;
+
+        $clientStorage = M::mock('League\OAuth2\Server\Storage\ClientInterface');
+        $clientStorage->shouldReceive('setServer');
+        $clientStorage->shouldReceive('get')->andReturn(
+            (new Client($server))->setId('testapp')
+        );
+
+        $sessionStorage = M::mock('League\OAuth2\Server\Storage\SessionInterface');
+        $sessionStorage->shouldReceive('setServer');
+        $sessionStorage->shouldReceive('create');
+        $sessionStorage->shouldReceive('getScopes')->andReturn([]);
+
+        $accessTokenStorage = M::mock('League\OAuth2\Server\Storage\AccessTokenInterface');
+        $accessTokenStorage->shouldReceive('setServer');
+        $accessTokenStorage->shouldReceive('create');
+        $accessTokenStorage->shouldReceive('getScopes')->andReturn([]);
+
+        $scopeStorage = M::mock('League\OAuth2\Server\Storage\ScopeInterface');
+        $scopeStorage->shouldReceive('setServer');
+        $scopeStorage->shouldReceive('get')->andReturn(null);
+
+        $server->setClientStorage($clientStorage);
+        $server->setScopeStorage($scopeStorage);
+        $server->setSessionStorage($sessionStorage);
+        $server->setAccessTokenStorage($accessTokenStorage);
+
+        $server->addGrantType($grant);
+        $server->issueAccessToken();
+    }
+
+    function testCompleteFlowInvalidScope()
+    {
+        $this->setExpectedException('League\OAuth2\Server\Exception\ClientException');
+
+        $_POST = [
+            'grant_type' => 'password',
+            'client_id' =>  'testapp',
+            'client_secret' =>  'foobar',
+            'scope' => 'foo'
+        ];
+
+        $server = new AuthorizationServer;
+        $grant = new Password;
+
+        $clientStorage = M::mock('League\OAuth2\Server\Storage\ClientInterface');
+        $clientStorage->shouldReceive('setServer');
+        $clientStorage->shouldReceive('get')->andReturn(
+            (new Client($server))->setId('testapp')
+        );
+
+        $sessionStorage = M::mock('League\OAuth2\Server\Storage\SessionInterface');
+        $sessionStorage->shouldReceive('setServer');
+        $sessionStorage->shouldReceive('create');
+        $sessionStorage->shouldReceive('getScopes')->andReturn([]);
+
+        $accessTokenStorage = M::mock('League\OAuth2\Server\Storage\AccessTokenInterface');
+        $accessTokenStorage->shouldReceive('setServer');
+        $accessTokenStorage->shouldReceive('create');
+        $accessTokenStorage->shouldReceive('getScopes')->andReturn([]);
+
+        $scopeStorage = M::mock('League\OAuth2\Server\Storage\ScopeInterface');
+        $scopeStorage->shouldReceive('setServer');
+        $scopeStorage->shouldReceive('get')->andReturn(null);
+
+        $server->setClientStorage($clientStorage);
+        $server->setScopeStorage($scopeStorage);
+        $server->setSessionStorage($sessionStorage);
+        $server->setAccessTokenStorage($accessTokenStorage);
+        $grant->setVerifyCredentialsCallback(function () {
+            return 123;
+        });
+
+        $server->addGrantType($grant);
+        $server->issueAccessToken();
+    }
+
+    function testCompleteFlowNoScopes()
+    {
+        $this->setExpectedException('League\OAuth2\Server\Exception\ClientException');
+
+        $_POST = [
+            'grant_type' => 'password',
+            'client_id' =>  'testapp',
+            'client_secret' =>  'foobar',
+            'username'  =>  'username',
+            'password'  =>  'password'
+        ];
+
+        $server = new AuthorizationServer;
+        $grant = new Password;
+
+        $clientStorage = M::mock('League\OAuth2\Server\Storage\ClientInterface');
+        $clientStorage->shouldReceive('setServer');
+        $clientStorage->shouldReceive('get')->andReturn(
+            (new Client($server))->setId('testapp')
+        );
+
+        $sessionStorage = M::mock('League\OAuth2\Server\Storage\SessionInterface');
+        $sessionStorage->shouldReceive('setServer');
+        $sessionStorage->shouldReceive('create')->andreturn(123);
+        $sessionStorage->shouldReceive('getScopes')->shouldReceive('getScopes')->andReturn([]);
+        $sessionStorage->shouldReceive('associateScope');
+
+        $accessTokenStorage = M::mock('League\OAuth2\Server\Storage\AccessTokenInterface');
+        $accessTokenStorage->shouldReceive('setServer');
+        $accessTokenStorage->shouldReceive('create');
+        $accessTokenStorage->shouldReceive('getScopes')->andReturn([]);
+        $accessTokenStorage->shouldReceive('associateScope');
+
+        $scopeStorage = M::mock('League\OAuth2\Server\Storage\ScopeInterface');
+        $scopeStorage->shouldReceive('setServer');
+
+        $server->setClientStorage($clientStorage);
+        $server->setScopeStorage($scopeStorage);
+        $server->setSessionStorage($sessionStorage);
+        $server->setAccessTokenStorage($accessTokenStorage);
+        $server->requireScopeParam(true);
+        $grant->setVerifyCredentialsCallback(function () {
+            return 123;
+        });
+
+        $server->addGrantType($grant);
+        $server->issueAccessToken();
+    }
+
+    function testCompleteFlowInvalidCredentials()
+    {
+        $this->setExpectedException('League\OAuth2\Server\Exception\ClientException');
+
+        $_POST = [
+            'grant_type' => 'password',
+            'client_id' =>  'testapp',
+            'client_secret' =>  'foobar',
+            'scope' =>  'foo',
+            'username'  =>  'username',
+            'password'  =>  'password'
+        ];
+
+        $server = new AuthorizationServer;
+        $grant = new Password;
+
+        $clientStorage = M::mock('League\OAuth2\Server\Storage\ClientInterface');
+        $clientStorage->shouldReceive('setServer');
+        $clientStorage->shouldReceive('get')->andReturn(
+            (new Client($server))->setId('testapp')
+        );
+
+        $sessionStorage = M::mock('League\OAuth2\Server\Storage\SessionInterface');
+        $sessionStorage->shouldReceive('setServer');
+        $sessionStorage->shouldReceive('create')->andreturn(123);
+        $sessionStorage->shouldReceive('getScopes')->shouldReceive('getScopes')->andReturn([
+            (new Scope($server))->setId('foo')
+        ]);
+        $sessionStorage->shouldReceive('associateScope');
+
+        $accessTokenStorage = M::mock('League\OAuth2\Server\Storage\AccessTokenInterface');
+        $accessTokenStorage->shouldReceive('setServer');
+        $accessTokenStorage->shouldReceive('create');
+        $accessTokenStorage->shouldReceive('getScopes')->andReturn([
+            (new Scope($server))->setId('foo')
+        ]);
+        $accessTokenStorage->shouldReceive('associateScope');
+
+        $scopeStorage = M::mock('League\OAuth2\Server\Storage\ScopeInterface');
+        $scopeStorage->shouldReceive('setServer');
+        $scopeStorage->shouldReceive('get')->andReturn(
+            (new Scope($server))->setId('foo')
+        );
+
+        $server->setClientStorage($clientStorage);
+        $server->setScopeStorage($scopeStorage);
+        $server->setSessionStorage($sessionStorage);
+        $server->setAccessTokenStorage($accessTokenStorage);
+        $grant->setVerifyCredentialsCallback(function () {
+            return false;
+        });
+
+        $server->addGrantType($grant);
+        $server->issueAccessToken();
+    }
+
+    function testCompleteFlow()
+    {
+        $_POST = [
+            'grant_type' => 'password',
+            'client_id' =>  'testapp',
+            'client_secret' =>  'foobar',
+            'scope' =>  'foo',
+            'username'  =>  'username',
+            'password'  =>  'password'
+        ];
+
+        $server = new AuthorizationServer;
+        $grant = new Password;
+
+        $clientStorage = M::mock('League\OAuth2\Server\Storage\ClientInterface');
+        $clientStorage->shouldReceive('setServer');
+        $clientStorage->shouldReceive('get')->andReturn(
+            (new Client($server))->setId('testapp')
+        );
+
+        $sessionStorage = M::mock('League\OAuth2\Server\Storage\SessionInterface');
+        $sessionStorage->shouldReceive('setServer');
+        $sessionStorage->shouldReceive('create')->andreturn(123);
+        $sessionStorage->shouldReceive('getScopes')->shouldReceive('getScopes')->andReturn([
+            (new Scope($server))->setId('foo')
+        ]);
+        $sessionStorage->shouldReceive('associateScope');
+
+        $accessTokenStorage = M::mock('League\OAuth2\Server\Storage\AccessTokenInterface');
+        $accessTokenStorage->shouldReceive('setServer');
+        $accessTokenStorage->shouldReceive('create');
+        $accessTokenStorage->shouldReceive('getScopes')->andReturn([
+            (new Scope($server))->setId('foo')
+        ]);
+        $accessTokenStorage->shouldReceive('associateScope');
+
+        $scopeStorage = M::mock('League\OAuth2\Server\Storage\ScopeInterface');
+        $scopeStorage->shouldReceive('setServer');
+        $scopeStorage->shouldReceive('get')->andReturn(
+            (new Scope($server))->setId('foo')
+        );
+
+        $server->setClientStorage($clientStorage);
+        $server->setScopeStorage($scopeStorage);
+        $server->setSessionStorage($sessionStorage);
+        $server->setAccessTokenStorage($accessTokenStorage);
+        $grant->setVerifyCredentialsCallback(function () {
+            return 123;
+        });
+
+        $server->addGrantType($grant);
+        $response = $server->issueAccessToken();
+
+        $this->assertTrue(isset($response['access_token']));
+        $this->assertTrue(isset($response['token_type']));
+        $this->assertTrue(isset($response['expires_in']));
+        $this->assertTrue(isset($response['expires']));
+    }
+
+    function testCompleteFlowRefreshToken()
+    {
+        $_POST = [
+            'grant_type' => 'password',
+            'client_id' =>  'testapp',
+            'client_secret' =>  'foobar',
+            'scope' =>  'foo',
+            'username'  =>  'username',
+            'password'  =>  'password'
+        ];
+
+        $server = new AuthorizationServer;
+        $grant = new Password;
+
+        $clientStorage = M::mock('League\OAuth2\Server\Storage\ClientInterface');
+        $clientStorage->shouldReceive('setServer');
+        $clientStorage->shouldReceive('get')->andReturn(
+            (new Client($server))->setId('testapp')
+        );
+
+        $sessionStorage = M::mock('League\OAuth2\Server\Storage\SessionInterface');
+        $sessionStorage->shouldReceive('setServer');
+        $sessionStorage->shouldReceive('create')->andreturn(123);
+        $sessionStorage->shouldReceive('getScopes')->shouldReceive('getScopes')->andReturn([
+            (new Scope($server))->setId('foo')
+        ]);
+        $sessionStorage->shouldReceive('associateScope');
+
+        $accessTokenStorage = M::mock('League\OAuth2\Server\Storage\AccessTokenInterface');
+        $accessTokenStorage->shouldReceive('setServer');
+        $accessTokenStorage->shouldReceive('create');
+        $accessTokenStorage->shouldReceive('getScopes')->andReturn([
+            (new Scope($server))->setId('foo')
+        ]);
+        $accessTokenStorage->shouldReceive('associateScope');
+
+        $scopeStorage = M::mock('League\OAuth2\Server\Storage\ScopeInterface');
+        $scopeStorage->shouldReceive('setServer');
+        $scopeStorage->shouldReceive('get')->andReturn(
+            (new Scope($server))->setId('foo')
+        );
+
+        $refreshTokenStorage = M::mock('League\OAuth2\Server\Storage\RefreshTokenInterface');
+        $refreshTokenStorage->shouldReceive('setServer');
+        $refreshTokenStorage->shouldReceive('create');
+        $refreshTokenStorage->shouldReceive('associateScope');
+
+        $server->setClientStorage($clientStorage);
+        $server->setScopeStorage($scopeStorage);
+        $server->setSessionStorage($sessionStorage);
+        $server->setAccessTokenStorage($accessTokenStorage);
+        $server->setRefreshTokenStorage($refreshTokenStorage);
+
+        $grant->setVerifyCredentialsCallback(function () {
+            return 123;
+        });
+
+        $server->addGrantType($grant);
+        $server->addGrantType(new RefreshToken);
+        $response = $server->issueAccessToken();
+
+        $this->assertTrue(isset($response['access_token']));
+        $this->assertTrue(isset($response['refresh_token']));
+        $this->assertTrue(isset($response['token_type']));
+        $this->assertTrue(isset($response['expires_in']));
+        $this->assertTrue(isset($response['expires']));
+    }
+}
\ No newline at end of file
diff --git a/tests/Grant/RefreshTokenTest.php b/tests/Grant/RefreshTokenTest.php
new file mode 100644
index 00000000..d0c2785e
--- /dev/null
+++ b/tests/Grant/RefreshTokenTest.php
@@ -0,0 +1,359 @@
+<?php
+
+namespace LeagueTests\Grant;
+
+use League\OAuth2\Server\Grant\RefreshToken;
+use League\OAuth2\Server\Entity\Scope;
+use League\OAuth2\Server\Entity\Client;
+use League\OAuth2\Server\Entity\AccessToken;
+use League\OAuth2\Server\Entity\Session;
+use League\OAuth2\Server\Entity\RefreshToken as RT;
+use League\OAuth2\Server\AuthorizationServer;
+use League\OAuth2\Server\Grant\ClientException;
+use Mockery as M;
+
+class RefreshTokenTest extends \PHPUnit_Framework_TestCase
+{
+    function testSetRefreshTokenTTL()
+    {
+        $grant = new RefreshToken;
+        $grant->setRefreshTokenTTL(86400);
+
+        $property = new \ReflectionProperty($grant, 'refreshTokenTTL');
+        $property->setAccessible(true);
+
+        $this->assertEquals(86400, $property->getValue($grant));
+    }
+
+    function testCompleteFlowMissingClientId()
+    {
+        $this->setExpectedException('League\OAuth2\Server\Exception\ClientException');
+
+        $_POST['grant_type'] = 'refresh_token';
+
+        $server = new AuthorizationServer;
+        $grant = new RefreshToken;
+
+        $server->addGrantType($grant);
+        $server->issueAccessToken();
+    }
+
+    function testCompleteFlowMissingClientSecret()
+    {
+        $this->setExpectedException('League\OAuth2\Server\Exception\ClientException');
+
+        $_POST = [
+            'grant_type' => 'refresh_token',
+            'client_id'  =>  'testapp'
+        ];
+
+        $server = new AuthorizationServer;
+        $grant = new RefreshToken;
+
+        $server->addGrantType($grant);
+        $server->issueAccessToken();
+    }
+
+    function testCompleteFlowInvalidClient()
+    {
+        $this->setExpectedException('League\OAuth2\Server\Exception\ClientException');
+
+        $_POST = [
+            'grant_type' => 'refresh_token',
+            'client_id' =>  'testapp',
+            'client_secret' =>  'foobar'
+        ];
+
+        $server = new AuthorizationServer;
+        $grant = new RefreshToken;
+
+        $clientStorage = M::mock('League\OAuth2\Server\Storage\ClientInterface');
+        $clientStorage->shouldReceive('setServer');
+        $clientStorage->shouldReceive('get')->andReturn(null);
+
+        $server->setClientStorage($clientStorage);
+
+        $server->addGrantType($grant);
+        $server->issueAccessToken();
+    }
+
+    function testCompleteFlowMissingRefreshToken()
+    {
+        $this->setExpectedException('League\OAuth2\Server\Exception\ClientException');
+
+        $_POST = [
+            'grant_type'    => 'refresh_token',
+            'client_id'     =>  'testapp',
+            'client_secret' =>  'foobar',
+        ];
+
+        $server = new AuthorizationServer;
+        $grant = new RefreshToken;
+
+        $clientStorage = M::mock('League\OAuth2\Server\Storage\ClientInterface');
+        $clientStorage->shouldReceive('setServer');
+        $clientStorage->shouldReceive('get')->andReturn(
+            (new Client($server))->setId('testapp')
+        );
+
+        $sessionStorage = M::mock('League\OAuth2\Server\Storage\SessionInterface');
+        $sessionStorage->shouldReceive('setServer');
+
+        $scopeStorage = M::mock('League\OAuth2\Server\Storage\ScopeInterface');
+        $scopeStorage->shouldReceive('setServer');
+
+        $server->setClientStorage($clientStorage);
+        $server->setScopeStorage($scopeStorage);
+        $server->setSessionStorage($sessionStorage);
+        $server->requireScopeParam(true);
+
+        $server->addGrantType($grant);
+        $server->issueAccessToken();
+    }
+
+    function testCompleteFlowInvalidRefreshToken()
+    {
+        $this->setExpectedException('League\OAuth2\Server\Exception\ClientException');
+
+        $_POST = [
+            'grant_type'    => 'refresh_token',
+            'client_id'     =>  'testapp',
+            'client_secret' =>  'foobar',
+            'refresh_token' =>  'meh'
+        ];
+
+        $server = new AuthorizationServer;
+        $grant = new RefreshToken;
+
+        $clientStorage = M::mock('League\OAuth2\Server\Storage\ClientInterface');
+        $clientStorage->shouldReceive('setServer');
+        $clientStorage->shouldReceive('get')->andReturn(
+            (new Client($server))->setId('testapp')
+        );
+
+        $refreshTokenStorage = M::mock('League\OAuth2\Server\Storage\RefreshTokenInterface');
+        $refreshTokenStorage->shouldReceive('get');
+        $refreshTokenStorage->shouldReceive('setServer');
+
+        $scopeStorage = M::mock('League\OAuth2\Server\Storage\ScopeInterface');
+        $scopeStorage->shouldReceive('setServer');
+
+        $server->setClientStorage($clientStorage);
+        $server->setScopeStorage($scopeStorage);
+        $server->setRefreshTokenStorage($refreshTokenStorage);
+        $server->requireScopeParam(true);
+
+        $server->addGrantType($grant);
+        $server->issueAccessToken();
+    }
+
+    function testCompleteFlowExistingScopes()
+    {
+        $_POST = [
+            'grant_type'    => 'refresh_token',
+            'client_id'     =>  'testapp',
+            'client_secret' =>  'foobar',
+            'refresh_token' =>  'refresh_token'
+        ];
+
+        $server = new AuthorizationServer;
+        $grant = new RefreshToken;
+
+        $clientStorage = M::mock('League\OAuth2\Server\Storage\ClientInterface');
+        $clientStorage->shouldReceive('setServer');
+        $clientStorage->shouldReceive('get')->andReturn(
+            (new Client($server))->setId('testapp')
+        );
+
+        $sessionStorage = M::mock('League\OAuth2\Server\Storage\SessionInterface');
+        $sessionStorage->shouldReceive('setServer');
+        $sessionStorage->shouldReceive('getScopes')->shouldReceive('getScopes')->andReturn([]);
+        $sessionStorage->shouldReceive('associateScope');
+        $sessionStorage->shouldReceive('getByAccessToken')->andReturn(
+            (new Session($server))
+        );
+
+        $accessTokenStorage = M::mock('League\OAuth2\Server\Storage\AccessTokenInterface');
+        $accessTokenStorage->shouldReceive('setServer');
+        $accessTokenStorage->shouldReceive('getByRefreshToken')->andReturn(
+            (new AccessToken($server))
+        );
+        $accessTokenStorage->shouldReceive('delete');
+        $accessTokenStorage->shouldReceive('create');
+        $accessTokenStorage->shouldReceive('getScopes')->andReturn([
+            (new Scope($server))->setId('foo')
+        ]);
+        $accessTokenStorage->shouldReceive('associateScope');
+
+        $refreshTokenStorage = M::mock('League\OAuth2\Server\Storage\RefreshTokenInterface');
+        $refreshTokenStorage->shouldReceive('setServer');
+        $refreshTokenStorage->shouldReceive('associateScope');
+        $refreshTokenStorage->shouldReceive('delete');
+        $refreshTokenStorage->shouldReceive('create');
+        $refreshTokenStorage->shouldReceive('get')->andReturn(
+            (new RT($server))
+        );
+
+        $scopeStorage = M::mock('League\OAuth2\Server\Storage\ScopeInterface');
+        $scopeStorage->shouldReceive('setServer');
+        $scopeStorage->shouldReceive('get')->andReturn(
+            (new Scope($server))->setId('foo')
+        );
+
+        $server->setClientStorage($clientStorage);
+        $server->setScopeStorage($scopeStorage);
+        $server->setSessionStorage($sessionStorage);
+        $server->setAccessTokenStorage($accessTokenStorage);
+        $server->setRefreshTokenStorage($refreshTokenStorage);
+
+        $server->addGrantType($grant);
+        $response = $server->issueAccessToken();
+
+        $this->assertTrue(isset($response['access_token']));
+        $this->assertTrue(isset($response['refresh_token']));
+        $this->assertTrue(isset($response['token_type']));
+        $this->assertTrue(isset($response['expires_in']));
+        $this->assertTrue(isset($response['expires']));
+    }
+
+    function testCompleteFlowRequestScopes()
+    {
+        $_POST = [
+            'grant_type'    => 'refresh_token',
+            'client_id'     =>  'testapp',
+            'client_secret' =>  'foobar',
+            'refresh_token' =>  'refresh_token',
+            'scope'         =>  'foo'
+        ];
+
+        $server = new AuthorizationServer;
+        $grant = new RefreshToken;
+
+        $oldSession = (new Session($server))->associateScope((new Scope($server))->setId('foo'));
+
+        $clientStorage = M::mock('League\OAuth2\Server\Storage\ClientInterface');
+        $clientStorage->shouldReceive('setServer');
+        $clientStorage->shouldReceive('get')->andReturn(
+            (new Client($server))->setId('testapp')
+        );
+
+        $sessionStorage = M::mock('League\OAuth2\Server\Storage\SessionInterface');
+        $sessionStorage->shouldReceive('setServer');
+        $sessionStorage->shouldReceive('getScopes')->shouldReceive('getScopes')->andReturn([]);
+        $sessionStorage->shouldReceive('associateScope');
+        $sessionStorage->shouldReceive('getByAccessToken')->andReturn(
+            $oldSession
+        );
+
+        $accessTokenStorage = M::mock('League\OAuth2\Server\Storage\AccessTokenInterface');
+        $accessTokenStorage->shouldReceive('setServer');
+        $accessTokenStorage->shouldReceive('getByRefreshToken')->andReturn(
+            (new AccessToken($server))
+        );
+        $accessTokenStorage->shouldReceive('delete');
+        $accessTokenStorage->shouldReceive('create');
+        $accessTokenStorage->shouldReceive('getScopes')->andReturn([
+            (new Scope($server))->setId('foo')
+        ]);
+        $accessTokenStorage->shouldReceive('associateScope');
+
+        $refreshTokenStorage = M::mock('League\OAuth2\Server\Storage\RefreshTokenInterface');
+        $refreshTokenStorage->shouldReceive('setServer');
+        $refreshTokenStorage->shouldReceive('associateScope');
+        $refreshTokenStorage->shouldReceive('delete');
+        $refreshTokenStorage->shouldReceive('create');
+        $refreshTokenStorage->shouldReceive('get')->andReturn(
+            (new RT($server))
+        );
+
+        $scopeStorage = M::mock('League\OAuth2\Server\Storage\ScopeInterface');
+        $scopeStorage->shouldReceive('setServer');
+        $scopeStorage->shouldReceive('get')->andReturn(
+            (new Scope($server))->setId('foo')
+        );
+
+        $server->setClientStorage($clientStorage);
+        $server->setScopeStorage($scopeStorage);
+        $server->setSessionStorage($sessionStorage);
+        $server->setAccessTokenStorage($accessTokenStorage);
+        $server->setRefreshTokenStorage($refreshTokenStorage);
+
+        $server->addGrantType($grant);
+        $response = $server->issueAccessToken();
+
+        $this->assertTrue(isset($response['access_token']));
+        $this->assertTrue(isset($response['refresh_token']));
+        $this->assertTrue(isset($response['token_type']));
+        $this->assertTrue(isset($response['expires_in']));
+        $this->assertTrue(isset($response['expires']));
+    }
+
+    function testCompleteFlowRequestScopesInvalid()
+    {
+        $_POST = [
+            'grant_type'    => 'refresh_token',
+            'client_id'     =>  'testapp',
+            'client_secret' =>  'foobar',
+            'refresh_token' =>  'refresh_token',
+            'scope'         =>  'blah'
+        ];
+
+        $server = new AuthorizationServer;
+        $grant = new RefreshToken;
+
+        $oldSession = (new Session($server))->associateScope((new Scope($server))->setId('foo'));
+
+        $clientStorage = M::mock('League\OAuth2\Server\Storage\ClientInterface');
+        $clientStorage->shouldReceive('setServer');
+        $clientStorage->shouldReceive('get')->andReturn(
+            (new Client($server))->setId('testapp')
+        );
+
+        $sessionStorage = M::mock('League\OAuth2\Server\Storage\SessionInterface');
+        $sessionStorage->shouldReceive('setServer');
+        $sessionStorage->shouldReceive('getScopes')->shouldReceive('getScopes')->andReturn([]);
+        $sessionStorage->shouldReceive('associateScope');
+        $sessionStorage->shouldReceive('getByAccessToken')->andReturn(
+            $oldSession
+        );
+
+        $accessTokenStorage = M::mock('League\OAuth2\Server\Storage\AccessTokenInterface');
+        $accessTokenStorage->shouldReceive('setServer');
+        $accessTokenStorage->shouldReceive('getByRefreshToken')->andReturn(
+            (new AccessToken($server))
+        );
+        $accessTokenStorage->shouldReceive('delete');
+        $accessTokenStorage->shouldReceive('create');
+        $accessTokenStorage->shouldReceive('getScopes')->andReturn([
+            (new Scope($server))->setId('foo')
+        ]);
+        $accessTokenStorage->shouldReceive('associateScope');
+
+        $refreshTokenStorage = M::mock('League\OAuth2\Server\Storage\RefreshTokenInterface');
+        $refreshTokenStorage->shouldReceive('setServer');
+        $refreshTokenStorage->shouldReceive('associateScope');
+        $refreshTokenStorage->shouldReceive('delete');
+        $refreshTokenStorage->shouldReceive('create');
+        $refreshTokenStorage->shouldReceive('get')->andReturn(
+            (new RT($server))
+        );
+
+        $scopeStorage = M::mock('League\OAuth2\Server\Storage\ScopeInterface');
+        $scopeStorage->shouldReceive('setServer');
+        $scopeStorage->shouldReceive('get')->andReturn(
+            (new Scope($server))->setId('blah')
+        );
+
+        $server->setClientStorage($clientStorage);
+        $server->setScopeStorage($scopeStorage);
+        $server->setSessionStorage($sessionStorage);
+        $server->setAccessTokenStorage($accessTokenStorage);
+        $server->setRefreshTokenStorage($refreshTokenStorage);
+
+        $server->addGrantType($grant);
+
+        $this->setExpectedException('League\OAuth2\Server\Exception\ClientException');
+
+        $server->issueAccessToken();
+    }
+}
\ No newline at end of file