diff --git a/lib/ApiOperations/All.php b/lib/ApiOperations/All.php
index 2762748f9..6ae462713 100644
--- a/lib/ApiOperations/All.php
+++ b/lib/ApiOperations/All.php
@@ -22,10 +22,10 @@ public static function all($params = null, $opts = null)
 
         list($response, $opts) = static::_staticRequest('get', $url, $params, $opts);
         $obj = \Stripe\Util\Util::convertToStripeObject($response->json, $opts);
-        if (!is_a($obj, 'Stripe\\Collection')) {
-            $class = get_class($obj);
-            $message = "Expected type \"Stripe\\Collection\", got \"$class\" instead";
-            throw new \Stripe\Error\Api($message);
+        if (!($obj instanceof \Stripe\Collection)) {
+            throw new \Stripe\Error\Api(
+                'Expected type ' . \Stripe\Collection::class . ', got "' . get_class($obj) . '" instead.'
+            );
         }
         $obj->setLastResponse($response);
         $obj->setRequestParams($params);
diff --git a/lib/Util/Util.php b/lib/Util/Util.php
index f9f154400..c86788697 100644
--- a/lib/Util/Util.php
+++ b/lib/Util/Util.php
@@ -67,88 +67,88 @@ public static function convertToStripeObject($resp, $opts)
     {
         $types = [
             // data structures
-            \Stripe\Collection::OBJECT_NAME => 'Stripe\\Collection',
+            \Stripe\Collection::OBJECT_NAME => \Stripe\Collection::class,
 
             // business objects
-            \Stripe\Account::OBJECT_NAME => 'Stripe\\Account',
-            \Stripe\AccountLink::OBJECT_NAME => 'Stripe\\AccountLink',
-            \Stripe\AlipayAccount::OBJECT_NAME => 'Stripe\\AlipayAccount',
-            \Stripe\ApplePayDomain::OBJECT_NAME => 'Stripe\\ApplePayDomain',
-            \Stripe\ApplicationFee::OBJECT_NAME => 'Stripe\\ApplicationFee',
-            \Stripe\Balance::OBJECT_NAME => 'Stripe\\Balance',
-            \Stripe\BalanceTransaction::OBJECT_NAME => 'Stripe\\BalanceTransaction',
-            \Stripe\BankAccount::OBJECT_NAME => 'Stripe\\BankAccount',
-            \Stripe\BitcoinReceiver::OBJECT_NAME => 'Stripe\\BitcoinReceiver',
-            \Stripe\BitcoinTransaction::OBJECT_NAME => 'Stripe\\BitcoinTransaction',
-            \Stripe\Capability::OBJECT_NAME => 'Stripe\\Capability',
-            \Stripe\Card::OBJECT_NAME => 'Stripe\\Card',
-            \Stripe\Charge::OBJECT_NAME => 'Stripe\\Charge',
-            \Stripe\Checkout\Session::OBJECT_NAME => 'Stripe\\Checkout\\Session',
-            \Stripe\CountrySpec::OBJECT_NAME => 'Stripe\\CountrySpec',
-            \Stripe\Coupon::OBJECT_NAME => 'Stripe\\Coupon',
-            \Stripe\CreditNote::OBJECT_NAME => 'Stripe\\CreditNote',
-            \Stripe\Customer::OBJECT_NAME => 'Stripe\\Customer',
-            \Stripe\CustomerBalanceTransaction::OBJECT_NAME => 'Stripe\\CustomerBalanceTransaction',
-            \Stripe\Discount::OBJECT_NAME => 'Stripe\\Discount',
-            \Stripe\Dispute::OBJECT_NAME => 'Stripe\\Dispute',
-            \Stripe\EphemeralKey::OBJECT_NAME => 'Stripe\\EphemeralKey',
-            \Stripe\Event::OBJECT_NAME => 'Stripe\\Event',
-            \Stripe\ExchangeRate::OBJECT_NAME => 'Stripe\\ExchangeRate',
-            \Stripe\ApplicationFeeRefund::OBJECT_NAME => 'Stripe\\ApplicationFeeRefund',
-            \Stripe\File::OBJECT_NAME => 'Stripe\\File',
-            \Stripe\File::OBJECT_NAME_ALT => 'Stripe\\File',
-            \Stripe\FileLink::OBJECT_NAME => 'Stripe\\FileLink',
-            \Stripe\Invoice::OBJECT_NAME => 'Stripe\\Invoice',
-            \Stripe\InvoiceItem::OBJECT_NAME => 'Stripe\\InvoiceItem',
-            \Stripe\InvoiceLineItem::OBJECT_NAME => 'Stripe\\InvoiceLineItem',
-            \Stripe\IssuerFraudRecord::OBJECT_NAME => 'Stripe\\IssuerFraudRecord',
-            \Stripe\Issuing\Authorization::OBJECT_NAME => 'Stripe\\Issuing\\Authorization',
-            \Stripe\Issuing\Card::OBJECT_NAME => 'Stripe\\Issuing\\Card',
-            \Stripe\Issuing\CardDetails::OBJECT_NAME => 'Stripe\\Issuing\\CardDetails',
-            \Stripe\Issuing\Cardholder::OBJECT_NAME => 'Stripe\\Issuing\\Cardholder',
-            \Stripe\Issuing\Dispute::OBJECT_NAME => 'Stripe\\Issuing\\Dispute',
-            \Stripe\Issuing\Transaction::OBJECT_NAME => 'Stripe\\Issuing\\Transaction',
-            \Stripe\LoginLink::OBJECT_NAME => 'Stripe\\LoginLink',
-            \Stripe\Order::OBJECT_NAME => 'Stripe\\Order',
-            \Stripe\OrderItem::OBJECT_NAME => 'Stripe\\OrderItem',
-            \Stripe\OrderReturn::OBJECT_NAME => 'Stripe\\OrderReturn',
-            \Stripe\PaymentIntent::OBJECT_NAME => 'Stripe\\PaymentIntent',
-            \Stripe\PaymentMethod::OBJECT_NAME => 'Stripe\\PaymentMethod',
-            \Stripe\Payout::OBJECT_NAME => 'Stripe\\Payout',
-            \Stripe\Person::OBJECT_NAME => 'Stripe\\Person',
-            \Stripe\Plan::OBJECT_NAME => 'Stripe\\Plan',
-            \Stripe\Product::OBJECT_NAME => 'Stripe\\Product',
-            \Stripe\Radar\EarlyFraudWarning::OBJECT_NAME => 'Stripe\\Radar\\EarlyFraudWarning',
-            \Stripe\Radar\ValueList::OBJECT_NAME => 'Stripe\\Radar\\ValueList',
-            \Stripe\Radar\ValueListItem::OBJECT_NAME => 'Stripe\\Radar\\ValueListItem',
-            \Stripe\Recipient::OBJECT_NAME => 'Stripe\\Recipient',
-            \Stripe\RecipientTransfer::OBJECT_NAME => 'Stripe\\RecipientTransfer',
-            \Stripe\Refund::OBJECT_NAME => 'Stripe\\Refund',
-            \Stripe\Reporting\ReportRun::OBJECT_NAME => 'Stripe\\Reporting\\ReportRun',
-            \Stripe\Reporting\ReportType::OBJECT_NAME => 'Stripe\\Reporting\\ReportType',
-            \Stripe\Review::OBJECT_NAME => 'Stripe\\Review',
-            \Stripe\SetupIntent::OBJECT_NAME => 'Stripe\\SetupIntent',
-            \Stripe\SKU::OBJECT_NAME => 'Stripe\\SKU',
-            \Stripe\Sigma\ScheduledQueryRun::OBJECT_NAME => 'Stripe\\Sigma\\ScheduledQueryRun',
-            \Stripe\Source::OBJECT_NAME => 'Stripe\\Source',
-            \Stripe\SourceTransaction::OBJECT_NAME => 'Stripe\\SourceTransaction',
-            \Stripe\Subscription::OBJECT_NAME => 'Stripe\\Subscription',
-            \Stripe\SubscriptionItem::OBJECT_NAME => 'Stripe\\SubscriptionItem',
-            \Stripe\SubscriptionSchedule::OBJECT_NAME => 'Stripe\\SubscriptionSchedule',
-            \Stripe\SubscriptionScheduleRevision::OBJECT_NAME => 'Stripe\\SubscriptionScheduleRevision',
-            \Stripe\TaxId::OBJECT_NAME => 'Stripe\\TaxId',
-            \Stripe\TaxRate::OBJECT_NAME => 'Stripe\\TaxRate',
-            \Stripe\ThreeDSecure::OBJECT_NAME => 'Stripe\\ThreeDSecure',
-            \Stripe\Terminal\ConnectionToken::OBJECT_NAME => 'Stripe\\Terminal\\ConnectionToken',
-            \Stripe\Terminal\Location::OBJECT_NAME => 'Stripe\\Terminal\\Location',
-            \Stripe\Terminal\Reader::OBJECT_NAME => 'Stripe\\Terminal\\Reader',
-            \Stripe\Token::OBJECT_NAME => 'Stripe\\Token',
-            \Stripe\Topup::OBJECT_NAME => 'Stripe\\Topup',
-            \Stripe\Transfer::OBJECT_NAME => 'Stripe\\Transfer',
-            \Stripe\TransferReversal::OBJECT_NAME => 'Stripe\\TransferReversal',
-            \Stripe\UsageRecord::OBJECT_NAME => 'Stripe\\UsageRecord',
-            \Stripe\UsageRecordSummary::OBJECT_NAME => 'Stripe\\UsageRecordSummary',
-            \Stripe\WebhookEndpoint::OBJECT_NAME => 'Stripe\\WebhookEndpoint',
+            \Stripe\Account::OBJECT_NAME => \Stripe\Account::class,
+            \Stripe\AccountLink::OBJECT_NAME => \Stripe\AccountLink::class,
+            \Stripe\AlipayAccount::OBJECT_NAME => \Stripe\AlipayAccount::class,
+            \Stripe\ApplePayDomain::OBJECT_NAME => \Stripe\ApplePayDomain::class,
+            \Stripe\ApplicationFee::OBJECT_NAME => \Stripe\ApplicationFee::class,
+            \Stripe\ApplicationFeeRefund::OBJECT_NAME => \Stripe\ApplicationFeeRefund::class,
+            \Stripe\Balance::OBJECT_NAME => \Stripe\Balance::class,
+            \Stripe\BalanceTransaction::OBJECT_NAME => \Stripe\BalanceTransaction::class,
+            \Stripe\BankAccount::OBJECT_NAME => \Stripe\BankAccount::class,
+            \Stripe\BitcoinReceiver::OBJECT_NAME => \Stripe\BitcoinReceiver::class,
+            \Stripe\BitcoinTransaction::OBJECT_NAME => \Stripe\BitcoinTransaction::class,
+            \Stripe\Capability::OBJECT_NAME => \Stripe\Capability::class,
+            \Stripe\Card::OBJECT_NAME => \Stripe\Card::class,
+            \Stripe\Charge::OBJECT_NAME => \Stripe\Charge::class,
+            \Stripe\Checkout\Session::OBJECT_NAME => \Stripe\Checkout\Session::class,
+            \Stripe\CountrySpec::OBJECT_NAME => \Stripe\CountrySpec::class,
+            \Stripe\Coupon::OBJECT_NAME => \Stripe\Coupon::class,
+            \Stripe\CreditNote::OBJECT_NAME => \Stripe\CreditNote::class,
+            \Stripe\Customer::OBJECT_NAME => \Stripe\Customer::class,
+            \Stripe\CustomerBalanceTransaction::OBJECT_NAME => \Stripe\CustomerBalanceTransaction::class,
+            \Stripe\Discount::OBJECT_NAME => \Stripe\Discount::class,
+            \Stripe\Dispute::OBJECT_NAME => \Stripe\Dispute::class,
+            \Stripe\EphemeralKey::OBJECT_NAME => \Stripe\EphemeralKey::class,
+            \Stripe\Event::OBJECT_NAME => \Stripe\Event::class,
+            \Stripe\ExchangeRate::OBJECT_NAME => \Stripe\ExchangeRate::class,
+            \Stripe\File::OBJECT_NAME => \Stripe\File::class,
+            \Stripe\File::OBJECT_NAME_ALT => \Stripe\File::class,
+            \Stripe\FileLink::OBJECT_NAME => \Stripe\FileLink::class,
+            \Stripe\Invoice::OBJECT_NAME => \Stripe\Invoice::class,
+            \Stripe\InvoiceItem::OBJECT_NAME => \Stripe\InvoiceItem::class,
+            \Stripe\InvoiceLineItem::OBJECT_NAME => \Stripe\InvoiceLineItem::class,
+            \Stripe\IssuerFraudRecord::OBJECT_NAME => \Stripe\IssuerFraudRecord::class,
+            \Stripe\Issuing\Authorization::OBJECT_NAME => \Stripe\Issuing\Authorization::class,
+            \Stripe\Issuing\Card::OBJECT_NAME => \Stripe\Issuing\Card::class,
+            \Stripe\Issuing\CardDetails::OBJECT_NAME => \Stripe\Issuing\CardDetails::class,
+            \Stripe\Issuing\Cardholder::OBJECT_NAME => \Stripe\Issuing\Cardholder::class,
+            \Stripe\Issuing\Dispute::OBJECT_NAME => \Stripe\Issuing\Dispute::class,
+            \Stripe\Issuing\Transaction::OBJECT_NAME => \Stripe\Issuing\Transaction::class,
+            \Stripe\LoginLink::OBJECT_NAME => \Stripe\LoginLink::class,
+            \Stripe\Order::OBJECT_NAME => \Stripe\Order::class,
+            \Stripe\OrderItem::OBJECT_NAME => \Stripe\OrderItem::class,
+            \Stripe\OrderReturn::OBJECT_NAME => \Stripe\OrderReturn::class,
+            \Stripe\PaymentIntent::OBJECT_NAME => \Stripe\PaymentIntent::class,
+            \Stripe\PaymentMethod::OBJECT_NAME => \Stripe\PaymentMethod::class,
+            \Stripe\Payout::OBJECT_NAME => \Stripe\Payout::class,
+            \Stripe\Person::OBJECT_NAME => \Stripe\Person::class,
+            \Stripe\Plan::OBJECT_NAME => \Stripe\Plan::class,
+            \Stripe\Product::OBJECT_NAME => \Stripe\Product::class,
+            \Stripe\Radar\EarlyFraudWarning::OBJECT_NAME => \Stripe\Radar\EarlyFraudWarning::class,
+            \Stripe\Radar\ValueList::OBJECT_NAME => \Stripe\Radar\ValueList::class,
+            \Stripe\Radar\ValueListItem::OBJECT_NAME => \Stripe\Radar\ValueListItem::class,
+            \Stripe\Recipient::OBJECT_NAME => \Stripe\Recipient::class,
+            \Stripe\RecipientTransfer::OBJECT_NAME => \Stripe\RecipientTransfer::class,
+            \Stripe\Refund::OBJECT_NAME => \Stripe\Refund::class,
+            \Stripe\Reporting\ReportRun::OBJECT_NAME => \Stripe\Reporting\ReportRun::class,
+            \Stripe\Reporting\ReportType::OBJECT_NAME => \Stripe\Reporting\ReportType::class,
+            \Stripe\Review::OBJECT_NAME => \Stripe\Review::class,
+            \Stripe\SetupIntent::OBJECT_NAME => \Stripe\SetupIntent::class,
+            \Stripe\Sigma\ScheduledQueryRun::OBJECT_NAME => \Stripe\Sigma\ScheduledQueryRun::class,
+            \Stripe\SKU::OBJECT_NAME => \Stripe\SKU::class,
+            \Stripe\Source::OBJECT_NAME => \Stripe\Source::class,
+            \Stripe\SourceTransaction::OBJECT_NAME => \Stripe\SourceTransaction::class,
+            \Stripe\Subscription::OBJECT_NAME => \Stripe\Subscription::class,
+            \Stripe\SubscriptionItem::OBJECT_NAME => \Stripe\SubscriptionItem::class,
+            \Stripe\SubscriptionSchedule::OBJECT_NAME => \Stripe\SubscriptionSchedule::class,
+            \Stripe\SubscriptionScheduleRevision::OBJECT_NAME => \Stripe\SubscriptionScheduleRevision::class,
+            \Stripe\TaxId::OBJECT_NAME => \Stripe\TaxId::class,
+            \Stripe\TaxRate::OBJECT_NAME => \Stripe\TaxRate::class,
+            \Stripe\ThreeDSecure::OBJECT_NAME => \Stripe\ThreeDSecure::class,
+            \Stripe\Terminal\ConnectionToken::OBJECT_NAME => \Stripe\Terminal\ConnectionToken::class,
+            \Stripe\Terminal\Location::OBJECT_NAME => \Stripe\Terminal\Location::class,
+            \Stripe\Terminal\Reader::OBJECT_NAME => \Stripe\Terminal\Reader::class,
+            \Stripe\Token::OBJECT_NAME => \Stripe\Token::class,
+            \Stripe\Topup::OBJECT_NAME => \Stripe\Topup::class,
+            \Stripe\Transfer::OBJECT_NAME => \Stripe\Transfer::class,
+            \Stripe\TransferReversal::OBJECT_NAME => \Stripe\TransferReversal::class,
+            \Stripe\UsageRecord::OBJECT_NAME => \Stripe\UsageRecord::class,
+            \Stripe\UsageRecordSummary::OBJECT_NAME => \Stripe\UsageRecordSummary::class,
+            \Stripe\WebhookEndpoint::OBJECT_NAME => \Stripe\WebhookEndpoint::class,
         ];
         if (self::isList($resp)) {
             $mapped = [];
@@ -160,7 +160,7 @@ public static function convertToStripeObject($resp, $opts)
             if (isset($resp['object']) && is_string($resp['object']) && isset($types[$resp['object']])) {
                 $class = $types[$resp['object']];
             } else {
-                $class = 'Stripe\\StripeObject';
+                $class = \Stripe\StripeObject::class;
             }
             return $class::constructFrom($resp, $opts);
         } else {
diff --git a/tests/Stripe/AccountLinkTest.php b/tests/Stripe/AccountLinkTest.php
index 86e6aafbb..0ecb2e239 100644
--- a/tests/Stripe/AccountLinkTest.php
+++ b/tests/Stripe/AccountLinkTest.php
@@ -16,6 +16,6 @@ public function testIsCreatable()
             "success_url" => "https://stripe.com/success",
             "type" => "custom_account_verification",
         ]);
-        $this->assertInstanceOf("Stripe\\AccountLink", $resource);
+        $this->assertInstanceOf(\Stripe\AccountLink::class, $resource);
     }
 }
diff --git a/tests/Stripe/AccountTest.php b/tests/Stripe/AccountTest.php
index 6d28d32ed..7b6f2d1b1 100644
--- a/tests/Stripe/AccountTest.php
+++ b/tests/Stripe/AccountTest.php
@@ -17,7 +17,7 @@ public function testIsListable()
         );
         $resources = Account::all();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\Account", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\Account::class, $resources->data[0]);
     }
 
     public function testIsRetrievable()
@@ -27,7 +27,7 @@ public function testIsRetrievable()
             '/v1/accounts/' . self::TEST_RESOURCE_ID
         );
         $resource = Account::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\Account", $resource);
+        $this->assertInstanceOf(\Stripe\Account::class, $resource);
     }
 
     public function testIsRetrievableWithoutId()
@@ -37,7 +37,7 @@ public function testIsRetrievableWithoutId()
             '/v1/account'
         );
         $resource = Account::retrieve();
-        $this->assertInstanceOf("Stripe\\Account", $resource);
+        $this->assertInstanceOf(\Stripe\Account::class, $resource);
     }
 
     public function testIsCreatable()
@@ -47,7 +47,7 @@ public function testIsCreatable()
             '/v1/accounts'
         );
         $resource = Account::create(["type" => "custom"]);
-        $this->assertInstanceOf("Stripe\\Account", $resource);
+        $this->assertInstanceOf(\Stripe\Account::class, $resource);
     }
 
     public function testIsSaveable()
@@ -59,7 +59,7 @@ public function testIsSaveable()
             '/v1/accounts/' . $resource->id
         );
         $resource->save();
-        $this->assertInstanceOf("Stripe\\Account", $resource);
+        $this->assertInstanceOf(\Stripe\Account::class, $resource);
     }
 
     public function testIsUpdatable()
@@ -71,7 +71,7 @@ public function testIsUpdatable()
         $resource = Account::update(self::TEST_RESOURCE_ID, [
             "metadata" => ["key" => "value"],
         ]);
-        $this->assertInstanceOf("Stripe\\Account", $resource);
+        $this->assertInstanceOf(\Stripe\Account::class, $resource);
     }
 
     public function testIsDeletable()
@@ -82,7 +82,7 @@ public function testIsDeletable()
             '/v1/accounts/' . $resource->id
         );
         $resource->delete();
-        $this->assertInstanceOf("Stripe\\Account", $resource);
+        $this->assertInstanceOf(\Stripe\Account::class, $resource);
     }
 
     public function testIsRejectable()
@@ -93,7 +93,7 @@ public function testIsRejectable()
             '/v1/accounts/' . $account->id . '/reject'
         );
         $resource = $account->reject(["reason" => "fraud"]);
-        $this->assertInstanceOf("Stripe\\Account", $resource);
+        $this->assertInstanceOf(\Stripe\Account::class, $resource);
         $this->assertSame($resource, $account);
     }
 
@@ -127,7 +127,7 @@ public function testPersons()
         );
         $persons = $account->persons();
         $this->assertTrue(is_array($persons->data));
-        $this->assertInstanceOf("Stripe\\Person", $persons->data[0]);
+        $this->assertInstanceOf(\Stripe\Person::class, $persons->data[0]);
     }
 
     public function testCanRetrieveCapability()
@@ -137,7 +137,7 @@ public function testCanRetrieveCapability()
             '/v1/accounts/' . self::TEST_RESOURCE_ID . '/capabilities/' . self::TEST_CAPABILITY_ID
         );
         $resource = Account::retrieveCapability(self::TEST_RESOURCE_ID, self::TEST_CAPABILITY_ID);
-        $this->assertInstanceOf("Stripe\\Capability", $resource);
+        $this->assertInstanceOf(\Stripe\Capability::class, $resource);
     }
 
     public function testCanUpdateCapability()
@@ -149,7 +149,7 @@ public function testCanUpdateCapability()
         $resource = Account::updateCapability(self::TEST_RESOURCE_ID, self::TEST_CAPABILITY_ID, [
             "requested" => true,
         ]);
-        $this->assertInstanceOf("Stripe\\Capability", $resource);
+        $this->assertInstanceOf(\Stripe\Capability::class, $resource);
     }
 
     public function testCanListCapabilities()
@@ -171,7 +171,7 @@ public function testCanCreateExternalAccount()
         $resource = Account::createExternalAccount(self::TEST_RESOURCE_ID, [
             "external_account" => "btok_123",
         ]);
-        $this->assertInstanceOf("Stripe\\BankAccount", $resource);
+        $this->assertInstanceOf(\Stripe\BankAccount::class, $resource);
     }
 
     public function testCanRetrieveExternalAccount()
@@ -181,7 +181,7 @@ public function testCanRetrieveExternalAccount()
             '/v1/accounts/' . self::TEST_RESOURCE_ID . '/external_accounts/' . self::TEST_EXTERNALACCOUNT_ID
         );
         $resource = Account::retrieveExternalAccount(self::TEST_RESOURCE_ID, self::TEST_EXTERNALACCOUNT_ID);
-        $this->assertInstanceOf("Stripe\\BankAccount", $resource);
+        $this->assertInstanceOf(\Stripe\BankAccount::class, $resource);
     }
 
     public function testCanUpdateExternalAccount()
@@ -193,7 +193,7 @@ public function testCanUpdateExternalAccount()
         $resource = Account::updateExternalAccount(self::TEST_RESOURCE_ID, self::TEST_EXTERNALACCOUNT_ID, [
             "name" => "name",
         ]);
-        $this->assertInstanceOf("Stripe\\BankAccount", $resource);
+        $this->assertInstanceOf(\Stripe\BankAccount::class, $resource);
     }
 
     public function testCanDeleteExternalAccount()
@@ -223,7 +223,7 @@ public function testCanCreateLoginLink()
             '/v1/accounts/' . self::TEST_RESOURCE_ID . '/login_links'
         );
         $resource = Account::createLoginLink(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\LoginLink", $resource);
+        $this->assertInstanceOf(\Stripe\LoginLink::class, $resource);
     }
 
     public function testCanCreatePerson()
@@ -239,7 +239,7 @@ public function testCanCreatePerson()
                 "year" => 1980
             ]
         ]);
-        $this->assertInstanceOf("Stripe\\Person", $resource);
+        $this->assertInstanceOf(\Stripe\Person::class, $resource);
     }
 
     public function testCanRetrievePerson()
@@ -249,7 +249,7 @@ public function testCanRetrievePerson()
             '/v1/accounts/' . self::TEST_RESOURCE_ID . '/persons/' . self::TEST_PERSON_ID
         );
         $resource = Account::retrievePerson(self::TEST_RESOURCE_ID, self::TEST_PERSON_ID);
-        $this->assertInstanceOf("Stripe\\Person", $resource);
+        $this->assertInstanceOf(\Stripe\Person::class, $resource);
     }
 
     public function testCanUpdatePerson()
@@ -261,7 +261,7 @@ public function testCanUpdatePerson()
         $resource = Account::updatePerson(self::TEST_RESOURCE_ID, self::TEST_PERSON_ID, [
             "first_name" => "First name",
         ]);
-        $this->assertInstanceOf("Stripe\\Person", $resource);
+        $this->assertInstanceOf(\Stripe\Person::class, $resource);
     }
 
     public function testCanDeletePerson()
diff --git a/tests/Stripe/AlipayAccountTest.php b/tests/Stripe/AlipayAccountTest.php
index 7159f5444..cb48a1007 100644
--- a/tests/Stripe/AlipayAccountTest.php
+++ b/tests/Stripe/AlipayAccountTest.php
@@ -50,7 +50,7 @@ public function testIsSaveable()
             '/v1/customers/cus_123/sources/' . self::TEST_RESOURCE_ID
         );
         $resource->save();
-        $this->assertSame("Stripe\\AlipayAccount", get_class($resource));
+        $this->assertSame(\Stripe\AlipayAccount::class, get_class($resource));
     }
 
     /**
@@ -71,6 +71,6 @@ public function testIsDeletable()
             '/v1/customers/cus_123/sources/' . self::TEST_RESOURCE_ID
         );
         $resource->delete();
-        $this->assertSame("Stripe\\AlipayAccount", get_class($resource));
+        $this->assertSame(\Stripe\AlipayAccount::class, get_class($resource));
     }
 }
diff --git a/tests/Stripe/ApiRequestorTest.php b/tests/Stripe/ApiRequestorTest.php
index ae79e5668..8105af7ff 100644
--- a/tests/Stripe/ApiRequestorTest.php
+++ b/tests/Stripe/ApiRequestorTest.php
@@ -8,7 +8,7 @@ class ApiRequestorTest extends TestCase
 {
     public function testEncodeObjects()
     {
-        $reflector = new \ReflectionClass('Stripe\\ApiRequestor');
+        $reflector = new \ReflectionClass(\Stripe\ApiRequestor::class);
         $method = $reflector->getMethod('_encodeObjects');
         $method->setAccessible(true);
 
@@ -38,7 +38,7 @@ public function testEncodeObjects()
 
     public function testHttpClientInjection()
     {
-        $reflector = new \ReflectionClass('Stripe\\ApiRequestor');
+        $reflector = new \ReflectionClass(\Stripe\ApiRequestor::class);
         $method = $reflector->getMethod('httpClient');
         $method->setAccessible(true);
 
@@ -52,7 +52,7 @@ public function testHttpClientInjection()
 
     public function testDefaultHeaders()
     {
-        $reflector = new \ReflectionClass('Stripe\\ApiRequestor');
+        $reflector = new \ReflectionClass(\Stripe\ApiRequestor::class);
         $method = $reflector->getMethod('_defaultHeaders');
         $method->setAccessible(true);
 
diff --git a/tests/Stripe/ApplePayDomainTest.php b/tests/Stripe/ApplePayDomainTest.php
index d033f55cb..5b64cabfd 100644
--- a/tests/Stripe/ApplePayDomainTest.php
+++ b/tests/Stripe/ApplePayDomainTest.php
@@ -14,7 +14,7 @@ public function testIsListable()
         );
         $resources = ApplePayDomain::all();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\ApplePayDomain", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\ApplePayDomain::class, $resources->data[0]);
     }
 
     public function testIsRetrievable()
@@ -24,7 +24,7 @@ public function testIsRetrievable()
             '/v1/apple_pay/domains/' . self::TEST_RESOURCE_ID
         );
         $resource = ApplePayDomain::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\ApplePayDomain", $resource);
+        $this->assertInstanceOf(\Stripe\ApplePayDomain::class, $resource);
     }
 
     public function testIsCreatable()
@@ -36,7 +36,7 @@ public function testIsCreatable()
         $resource = ApplePayDomain::create([
             "domain_name" => "domain",
         ]);
-        $this->assertInstanceOf("Stripe\\ApplePayDomain", $resource);
+        $this->assertInstanceOf(\Stripe\ApplePayDomain::class, $resource);
     }
 
     public function testIsDeletable()
@@ -47,6 +47,6 @@ public function testIsDeletable()
             '/v1/apple_pay/domains/' . $resource->id
         );
         $resource->delete();
-        $this->assertInstanceOf("Stripe\\ApplePayDomain", $resource);
+        $this->assertInstanceOf(\Stripe\ApplePayDomain::class, $resource);
     }
 }
diff --git a/tests/Stripe/ApplicationFeeRefundTest.php b/tests/Stripe/ApplicationFeeRefundTest.php
index 9af059ff7..fda6feea1 100644
--- a/tests/Stripe/ApplicationFeeRefundTest.php
+++ b/tests/Stripe/ApplicationFeeRefundTest.php
@@ -16,6 +16,6 @@ public function testIsSaveable()
             '/v1/application_fees/' . $resource->fee . '/refunds/' . $resource->id
         );
         $resource->save();
-        $this->assertInstanceOf("Stripe\\ApplicationFeeRefund", $resource);
+        $this->assertInstanceOf(\Stripe\ApplicationFeeRefund::class, $resource);
     }
 }
diff --git a/tests/Stripe/ApplicationFeeTest.php b/tests/Stripe/ApplicationFeeTest.php
index 66e007ff3..2feb4ccd1 100644
--- a/tests/Stripe/ApplicationFeeTest.php
+++ b/tests/Stripe/ApplicationFeeTest.php
@@ -15,7 +15,7 @@ public function testIsListable()
         );
         $resources = ApplicationFee::all();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\ApplicationFee", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\ApplicationFee::class, $resources->data[0]);
     }
 
     public function testIsRetrievable()
@@ -25,7 +25,7 @@ public function testIsRetrievable()
             '/v1/application_fees/' . self::TEST_RESOURCE_ID
         );
         $resource = ApplicationFee::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\ApplicationFee", $resource);
+        $this->assertInstanceOf(\Stripe\ApplicationFee::class, $resource);
     }
 
     public function testIsRefundable()
@@ -36,7 +36,7 @@ public function testIsRefundable()
             '/v1/application_fees/' . $fee->id . '/refunds'
         );
         $resource = $fee->refund();
-        $this->assertInstanceOf("Stripe\\ApplicationFee", $resource);
+        $this->assertInstanceOf(\Stripe\ApplicationFee::class, $resource);
         $this->assertSame($resource, $fee);
     }
 
@@ -47,7 +47,7 @@ public function testCanCreateRefund()
             '/v1/application_fees/' . self::TEST_RESOURCE_ID . '/refunds'
         );
         $resource = ApplicationFee::createRefund(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\ApplicationFeeRefund", $resource);
+        $this->assertInstanceOf(\Stripe\ApplicationFeeRefund::class, $resource);
     }
 
     public function testCanRetrieveRefund()
@@ -57,7 +57,7 @@ public function testCanRetrieveRefund()
             '/v1/application_fees/' . self::TEST_RESOURCE_ID . '/refunds/' . self::TEST_FEEREFUND_ID
         );
         $resource = ApplicationFee::retrieveRefund(self::TEST_RESOURCE_ID, self::TEST_FEEREFUND_ID);
-        $this->assertInstanceOf("Stripe\\ApplicationFeeRefund", $resource);
+        $this->assertInstanceOf(\Stripe\ApplicationFeeRefund::class, $resource);
     }
 
     public function testCanUpdateRefund()
@@ -67,7 +67,7 @@ public function testCanUpdateRefund()
             '/v1/application_fees/' . self::TEST_RESOURCE_ID . '/refunds/' . self::TEST_FEEREFUND_ID
         );
         $resource = ApplicationFee::updateRefund(self::TEST_RESOURCE_ID, self::TEST_FEEREFUND_ID);
-        $this->assertInstanceOf("Stripe\\ApplicationFeeRefund", $resource);
+        $this->assertInstanceOf(\Stripe\ApplicationFeeRefund::class, $resource);
     }
 
     public function testCanListRefunds()
@@ -78,6 +78,6 @@ public function testCanListRefunds()
         );
         $resources = ApplicationFee::allRefunds(self::TEST_RESOURCE_ID);
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\ApplicationFeeRefund", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\ApplicationFeeRefund::class, $resources->data[0]);
     }
 }
diff --git a/tests/Stripe/BalanceTest.php b/tests/Stripe/BalanceTest.php
index ccbdbdfb7..dbdcd8e68 100644
--- a/tests/Stripe/BalanceTest.php
+++ b/tests/Stripe/BalanceTest.php
@@ -11,6 +11,6 @@ public function testIsRetrievable()
             '/v1/balance'
         );
         $resource = Balance::retrieve();
-        $this->assertInstanceOf("Stripe\\Balance", $resource);
+        $this->assertInstanceOf(\Stripe\Balance::class, $resource);
     }
 }
diff --git a/tests/Stripe/BalanceTransactionTest.php b/tests/Stripe/BalanceTransactionTest.php
index ed5be3e1b..ea7921490 100644
--- a/tests/Stripe/BalanceTransactionTest.php
+++ b/tests/Stripe/BalanceTransactionTest.php
@@ -14,7 +14,7 @@ public function testIsListable()
         );
         $resources = BalanceTransaction::all();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\BalanceTransaction", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\BalanceTransaction::class, $resources->data[0]);
     }
 
     public function testIsRetrievable()
@@ -24,6 +24,6 @@ public function testIsRetrievable()
             '/v1/balance_transactions/' . self::TEST_RESOURCE_ID
         );
         $resource = BalanceTransaction::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\BalanceTransaction", $resource);
+        $this->assertInstanceOf(\Stripe\BalanceTransaction::class, $resource);
     }
 }
diff --git a/tests/Stripe/BankAccountTest.php b/tests/Stripe/BankAccountTest.php
index ab1dff9d5..33ab4f792 100644
--- a/tests/Stripe/BankAccountTest.php
+++ b/tests/Stripe/BankAccountTest.php
@@ -59,7 +59,7 @@ public function testIsSaveable()
             '/v1/customers/cus_123/sources/' . self::TEST_RESOURCE_ID
         );
         $resource->save();
-        $this->assertSame("Stripe\\BankAccount", get_class($resource));
+        $this->assertSame(\Stripe\BankAccount::class, get_class($resource));
     }
 
     /**
@@ -80,7 +80,7 @@ public function testIsDeletable()
             '/v1/customers/cus_123/sources/' . self::TEST_RESOURCE_ID
         );
         $resource->delete();
-        $this->assertSame("Stripe\\BankAccount", get_class($resource));
+        $this->assertSame(\Stripe\BankAccount::class, get_class($resource));
     }
 
     public function testIsVerifiable()
@@ -94,6 +94,6 @@ public function testIsVerifiable()
             ]
         );
         $resource->verify(["amounts" => [1, 2]]);
-        $this->assertInstanceOf("Stripe\\BankAccount", $resource);
+        $this->assertInstanceOf(\Stripe\BankAccount::class, $resource);
     }
 }
diff --git a/tests/Stripe/BitcoinReceiverTest.php b/tests/Stripe/BitcoinReceiverTest.php
index cea999fc4..2da919259 100644
--- a/tests/Stripe/BitcoinReceiverTest.php
+++ b/tests/Stripe/BitcoinReceiverTest.php
@@ -47,7 +47,7 @@ public function testIsListable()
         );
         $resources = BitcoinReceiver::all();
         $this->assertTrue(is_array($resources->data));
-        $this->assertSame("Stripe\\BitcoinReceiver", get_class($resources->data[0]));
+        $this->assertSame(\Stripe\BitcoinReceiver::class, get_class($resources->data[0]));
     }
 
     public function testIsRetrievable()
@@ -57,6 +57,6 @@ public function testIsRetrievable()
             '/v1/bitcoin/receivers/' . self::TEST_RESOURCE_ID
         );
         $resource = BitcoinReceiver::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertSame("Stripe\\BitcoinReceiver", get_class($resource));
+        $this->assertSame(\Stripe\BitcoinReceiver::class, get_class($resource));
     }
 }
diff --git a/tests/Stripe/CapabilityTest.php b/tests/Stripe/CapabilityTest.php
index 45f6b6332..1d0b80717 100644
--- a/tests/Stripe/CapabilityTest.php
+++ b/tests/Stripe/CapabilityTest.php
@@ -33,7 +33,7 @@ public function testIsSaveable()
             '/v1/accounts/' . self::TEST_ACCOUNT_ID . '/capabilities/' . self::TEST_RESOURCE_ID
         );
         $resource->save();
-        $this->assertSame("Stripe\\Capability", get_class($resource));
+        $this->assertInstanceOf(\Stripe\Capability::class, $resource);
     }
 
     /**
diff --git a/tests/Stripe/CardTest.php b/tests/Stripe/CardTest.php
index 8976eff66..ec19558f1 100644
--- a/tests/Stripe/CardTest.php
+++ b/tests/Stripe/CardTest.php
@@ -68,7 +68,7 @@ public function testIsSaveable()
             '/v1/customers/cus_123/sources/' . self::TEST_RESOURCE_ID
         );
         $resource->save();
-        $this->assertSame("Stripe\\Card", get_class($resource));
+        $this->assertSame(\Stripe\Card::class, get_class($resource));
     }
 
     /**
@@ -89,6 +89,6 @@ public function testIsDeletable()
             '/v1/customers/cus_123/sources/' . self::TEST_RESOURCE_ID
         );
         $resource->delete();
-        $this->assertSame("Stripe\\Card", get_class($resource));
+        $this->assertSame(\Stripe\Card::class, get_class($resource));
     }
 }
diff --git a/tests/Stripe/ChargeTest.php b/tests/Stripe/ChargeTest.php
index b8c6cbabf..f609b50b7 100644
--- a/tests/Stripe/ChargeTest.php
+++ b/tests/Stripe/ChargeTest.php
@@ -14,7 +14,7 @@ public function testIsListable()
         );
         $resources = Charge::all();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\Charge", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\Charge::class, $resources->data[0]);
     }
 
     public function testIsRetrievable()
@@ -24,7 +24,7 @@ public function testIsRetrievable()
             '/v1/charges/' . self::TEST_RESOURCE_ID
         );
         $resource = Charge::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\Charge", $resource);
+        $this->assertInstanceOf(\Stripe\Charge::class, $resource);
     }
 
     public function testIsCreatable()
@@ -38,7 +38,7 @@ public function testIsCreatable()
             "currency" => "usd",
             "source" => "tok_123"
         ]);
-        $this->assertInstanceOf("Stripe\\Charge", $resource);
+        $this->assertInstanceOf(\Stripe\Charge::class, $resource);
     }
 
     public function testIsSaveable()
@@ -50,7 +50,7 @@ public function testIsSaveable()
             '/v1/charges/' . $resource->id
         );
         $resource->save();
-        $this->assertInstanceOf("Stripe\\Charge", $resource);
+        $this->assertInstanceOf(\Stripe\Charge::class, $resource);
     }
 
     public function testIsUpdatable()
@@ -62,7 +62,7 @@ public function testIsUpdatable()
         $resource = Charge::update(self::TEST_RESOURCE_ID, [
             "metadata" => ["key" => "value"],
         ]);
-        $this->assertInstanceOf("Stripe\\Charge", $resource);
+        $this->assertInstanceOf(\Stripe\Charge::class, $resource);
     }
 
     public function testCanRefund()
@@ -73,7 +73,7 @@ public function testCanRefund()
             '/v1/charges/' . $charge->id . '/refund'
         );
         $resource = $charge->refund();
-        $this->assertInstanceOf("Stripe\\Charge", $resource);
+        $this->assertInstanceOf(\Stripe\Charge::class, $resource);
         $this->assertSame($resource, $charge);
     }
 
@@ -85,7 +85,7 @@ public function testCanCapture()
             '/v1/charges/' . $charge->id . '/capture'
         );
         $resource = $charge->capture();
-        $this->assertInstanceOf("Stripe\\Charge", $resource);
+        $this->assertInstanceOf(\Stripe\Charge::class, $resource);
         $this->assertSame($resource, $charge);
     }
 
@@ -97,7 +97,7 @@ public function testCanUpdateDispute()
             '/v1/charges/' . $charge->id . '/dispute'
         );
         $resource = $charge->updateDispute();
-        $this->assertInstanceOf("Stripe\\Dispute", $resource);
+        $this->assertInstanceOf(\Stripe\Dispute::class, $resource);
     }
 
     public function testCanCloseDispute()
@@ -108,7 +108,7 @@ public function testCanCloseDispute()
             '/v1/charges/' . $charge->id . '/dispute/close'
         );
         $resource = $charge->closeDispute();
-        $this->assertInstanceOf("Stripe\\Charge", $resource);
+        $this->assertInstanceOf(\Stripe\Charge::class, $resource);
         $this->assertSame($resource, $charge);
     }
 
@@ -121,7 +121,7 @@ public function testCanMarkAsFraudulent()
             ['fraud_details' => ['user_report' => 'fraudulent']]
         );
         $resource = $charge->markAsFraudulent();
-        $this->assertInstanceOf("Stripe\\Charge", $resource);
+        $this->assertInstanceOf(\Stripe\Charge::class, $resource);
         $this->assertSame($resource, $charge);
     }
 
@@ -134,7 +134,7 @@ public function testCanMarkAsSafe()
             ['fraud_details' => ['user_report' => 'safe']]
         );
         $resource = $charge->markAsSafe();
-        $this->assertInstanceOf("Stripe\\Charge", $resource);
+        $this->assertInstanceOf(\Stripe\Charge::class, $resource);
         $this->assertSame($resource, $charge);
     }
 }
diff --git a/tests/Stripe/Checkout/SessionTest.php b/tests/Stripe/Checkout/SessionTest.php
index 56b0f22fe..81ca4f3b0 100644
--- a/tests/Stripe/Checkout/SessionTest.php
+++ b/tests/Stripe/Checkout/SessionTest.php
@@ -33,7 +33,7 @@ public function testIsCreatable()
             'payment_method_types' => ['card'],
             'success_url' => 'https://stripe.com/success'
         ]);
-        $this->assertInstanceOf('Stripe\\Checkout\\Session', $resource);
+        $this->assertInstanceOf(\Stripe\Checkout\Session::class, $resource);
     }
 
     public function testIsRetrievable()
@@ -43,6 +43,6 @@ public function testIsRetrievable()
             '/v1/checkout/sessions/' . self::TEST_RESOURCE_ID
         );
         $resource = Session::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\Checkout\\Session", $resource);
+        $this->assertInstanceOf(\Stripe\Checkout\Session::class, $resource);
     }
 }
diff --git a/tests/Stripe/CountrySpecTest.php b/tests/Stripe/CountrySpecTest.php
index cccd41168..c4ecd45f2 100644
--- a/tests/Stripe/CountrySpecTest.php
+++ b/tests/Stripe/CountrySpecTest.php
@@ -14,7 +14,7 @@ public function testIsListable()
         );
         $resources = CountrySpec::all();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\CountrySpec", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\CountrySpec::class, $resources->data[0]);
     }
 
     public function testIsRetrievable()
@@ -24,6 +24,6 @@ public function testIsRetrievable()
             '/v1/country_specs/' . self::TEST_RESOURCE_ID
         );
         $resource = CountrySpec::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\CountrySpec", $resource);
+        $this->assertInstanceOf(\Stripe\CountrySpec::class, $resource);
     }
 }
diff --git a/tests/Stripe/CouponTest.php b/tests/Stripe/CouponTest.php
index 8a6fbf630..dfb274db0 100644
--- a/tests/Stripe/CouponTest.php
+++ b/tests/Stripe/CouponTest.php
@@ -14,7 +14,7 @@ public function testIsListable()
         );
         $resources = Coupon::all();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\Coupon", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\Coupon::class, $resources->data[0]);
     }
 
     public function testIsRetrievable()
@@ -24,7 +24,7 @@ public function testIsRetrievable()
             '/v1/coupons/' . self::TEST_RESOURCE_ID
         );
         $resource = Coupon::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\Coupon", $resource);
+        $this->assertInstanceOf(\Stripe\Coupon::class, $resource);
     }
 
     public function testIsCreatable()
@@ -39,7 +39,7 @@ public function testIsCreatable()
             "duration_in_months" => 3,
             "id" => self::TEST_RESOURCE_ID,
         ]);
-        $this->assertInstanceOf("Stripe\\Coupon", $resource);
+        $this->assertInstanceOf(\Stripe\Coupon::class, $resource);
     }
 
     public function testIsSaveable()
@@ -51,7 +51,7 @@ public function testIsSaveable()
             '/v1/coupons/' . self::TEST_RESOURCE_ID
         );
         $resource->save();
-        $this->assertInstanceOf("Stripe\\Coupon", $resource);
+        $this->assertInstanceOf(\Stripe\Coupon::class, $resource);
     }
 
     public function testIsUpdatable()
@@ -63,7 +63,7 @@ public function testIsUpdatable()
         $resource = Coupon::update(self::TEST_RESOURCE_ID, [
             "metadata" => ["key" => "value"],
         ]);
-        $this->assertInstanceOf("Stripe\\Coupon", $resource);
+        $this->assertInstanceOf(\Stripe\Coupon::class, $resource);
     }
 
     public function testIsDeletable()
@@ -74,6 +74,6 @@ public function testIsDeletable()
             '/v1/coupons/' . self::TEST_RESOURCE_ID
         );
         $resource->delete();
-        $this->assertInstanceOf("Stripe\\Coupon", $resource);
+        $this->assertInstanceOf(\Stripe\Coupon::class, $resource);
     }
 }
diff --git a/tests/Stripe/CreditNoteTest.php b/tests/Stripe/CreditNoteTest.php
index c256bb91c..c05c811d9 100644
--- a/tests/Stripe/CreditNoteTest.php
+++ b/tests/Stripe/CreditNoteTest.php
@@ -14,7 +14,7 @@ public function testIsListable()
         );
         $resources = CreditNote::all();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\CreditNote", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\CreditNote::class, $resources->data[0]);
     }
 
     public function testIsRetrievable()
@@ -24,7 +24,7 @@ public function testIsRetrievable()
             '/v1/credit_notes/' . self::TEST_RESOURCE_ID
         );
         $resource = CreditNote::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\CreditNote", $resource);
+        $this->assertInstanceOf(\Stripe\CreditNote::class, $resource);
     }
 
     public function testIsCreatable()
@@ -38,7 +38,7 @@ public function testIsCreatable()
             "invoice" => "in_132",
             "reason" => "duplicate",
         ]);
-        $this->assertInstanceOf("Stripe\\CreditNote", $resource);
+        $this->assertInstanceOf(\Stripe\CreditNote::class, $resource);
     }
 
     public function testIsSaveable()
@@ -50,7 +50,7 @@ public function testIsSaveable()
             '/v1/credit_notes/' . $resource->id
         );
         $resource->save();
-        $this->assertInstanceOf("Stripe\\CreditNote", $resource);
+        $this->assertInstanceOf(\Stripe\CreditNote::class, $resource);
     }
 
     public function testIsUpdatable()
@@ -62,7 +62,7 @@ public function testIsUpdatable()
         $resource = CreditNote::update(self::TEST_RESOURCE_ID, [
             "metadata" => ["key" => "value"],
         ]);
-        $this->assertInstanceOf("Stripe\\CreditNote", $resource);
+        $this->assertInstanceOf(\Stripe\CreditNote::class, $resource);
     }
 
     public function testCanVoidCreditNote()
@@ -73,7 +73,7 @@ public function testCanVoidCreditNote()
             '/v1/credit_notes/' . $creditNote->id . '/void'
         );
         $resource = $creditNote->voidCreditNote();
-        $this->assertInstanceOf("Stripe\\CreditNote", $resource);
+        $this->assertInstanceOf(\Stripe\CreditNote::class, $resource);
         $this->assertSame($resource, $creditNote);
     }
 }
diff --git a/tests/Stripe/CustomerTest.php b/tests/Stripe/CustomerTest.php
index 3b1eeadbe..3f143483d 100644
--- a/tests/Stripe/CustomerTest.php
+++ b/tests/Stripe/CustomerTest.php
@@ -17,7 +17,7 @@ public function testIsListable()
         );
         $resources = Customer::all();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\Customer", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\Customer::class, $resources->data[0]);
     }
 
     public function testIsRetrievable()
@@ -27,7 +27,7 @@ public function testIsRetrievable()
             '/v1/customers/' . self::TEST_RESOURCE_ID
         );
         $resource = Customer::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\Customer", $resource);
+        $this->assertInstanceOf(\Stripe\Customer::class, $resource);
     }
 
     public function testIsCreatable()
@@ -37,7 +37,7 @@ public function testIsCreatable()
             '/v1/customers'
         );
         $resource = Customer::create();
-        $this->assertInstanceOf("Stripe\\Customer", $resource);
+        $this->assertInstanceOf(\Stripe\Customer::class, $resource);
     }
 
     public function testIsSaveable()
@@ -49,7 +49,7 @@ public function testIsSaveable()
             '/v1/customers/' . $resource->id
         );
         $resource->save();
-        $this->assertInstanceOf("Stripe\\Customer", $resource);
+        $this->assertInstanceOf(\Stripe\Customer::class, $resource);
     }
 
     public function testIsUpdatable()
@@ -61,7 +61,7 @@ public function testIsUpdatable()
         $resource = Customer::update(self::TEST_RESOURCE_ID, [
             "metadata" => ["key" => "value"],
         ]);
-        $this->assertInstanceOf("Stripe\\Customer", $resource);
+        $this->assertInstanceOf(\Stripe\Customer::class, $resource);
     }
 
     public function testIsDeletable()
@@ -72,7 +72,7 @@ public function testIsDeletable()
             '/v1/customers/' . $resource->id
         );
         $resource->delete();
-        $this->assertInstanceOf("Stripe\\Customer", $resource);
+        $this->assertInstanceOf(\Stripe\Customer::class, $resource);
     }
 
     public function testCanAddInvoiceItem()
@@ -91,7 +91,7 @@ public function testCanAddInvoiceItem()
             "amount" => 100,
             "currency" => "usd"
         ]);
-        $this->assertInstanceOf("Stripe\\InvoiceItem", $resource);
+        $this->assertInstanceOf(\Stripe\InvoiceItem::class, $resource);
     }
 
     public function testCanListInvoices()
@@ -104,7 +104,7 @@ public function testCanListInvoices()
         );
         $resources = $customer->invoices();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\Invoice", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\Invoice::class, $resources->data[0]);
     }
 
     public function testCanListInvoiceItems()
@@ -117,7 +117,7 @@ public function testCanListInvoiceItems()
         );
         $resources = $customer->invoiceItems();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\InvoiceItem", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\InvoiceItem::class, $resources->data[0]);
     }
 
     public function testCanListCharges()
@@ -130,7 +130,7 @@ public function testCanListCharges()
         );
         $resources = $customer->charges();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\Charge", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\Charge::class, $resources->data[0]);
     }
 
     public function testCanUpdateSubscription()
@@ -148,7 +148,7 @@ public function testCanUpdateSubscription()
             ]
         );
         $resource = $customer->updateSubscription(["plan" => "plan"]);
-        $this->assertInstanceOf("Stripe\\Subscription", $resource);
+        $this->assertInstanceOf(\Stripe\Subscription::class, $resource);
         $this->assertSame("sub_foo", $customer->subscription->id);
     }
 
@@ -167,7 +167,7 @@ public function testCanCancelSubscription()
             ]
         );
         $resource = $customer->cancelSubscription();
-        $this->assertInstanceOf("Stripe\\Subscription", $resource);
+        $this->assertInstanceOf(\Stripe\Subscription::class, $resource);
         $this->assertSame("sub_foo", $customer->subscription->id);
     }
 
@@ -208,7 +208,7 @@ public function testCanUpdateSource()
         );
         $resource = Customer::updateSource(self::TEST_RESOURCE_ID, self::TEST_SOURCE_ID, ["name" => "name"]);
         // stripe-mock returns a Card on this method and not a bank account
-        $this->assertInstanceOf("Stripe\\Card", $resource);
+        $this->assertInstanceOf(\Stripe\Card::class, $resource);
     }
 
     public function testCanDeleteSource()
diff --git a/tests/Stripe/DisputeTest.php b/tests/Stripe/DisputeTest.php
index 81d93da02..67ddb1d80 100644
--- a/tests/Stripe/DisputeTest.php
+++ b/tests/Stripe/DisputeTest.php
@@ -14,7 +14,7 @@ public function testIsListable()
         );
         $resources = Dispute::all();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\Dispute", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\Dispute::class, $resources->data[0]);
     }
 
     public function testIsRetrievable()
@@ -24,7 +24,7 @@ public function testIsRetrievable()
             '/v1/disputes/' . self::TEST_RESOURCE_ID
         );
         $resource = Dispute::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\Dispute", $resource);
+        $this->assertInstanceOf(\Stripe\Dispute::class, $resource);
     }
 
     public function testIsSaveable()
@@ -36,7 +36,7 @@ public function testIsSaveable()
             '/v1/disputes/' . $resource->id
         );
         $resource->save();
-        $this->assertInstanceOf("Stripe\\Dispute", $resource);
+        $this->assertInstanceOf(\Stripe\Dispute::class, $resource);
     }
 
     public function testIsUpdatable()
@@ -48,7 +48,7 @@ public function testIsUpdatable()
         $resource = Dispute::update(self::TEST_RESOURCE_ID, [
             "metadata" => ["key" => "value"],
         ]);
-        $this->assertInstanceOf("Stripe\\Dispute", $resource);
+        $this->assertInstanceOf(\Stripe\Dispute::class, $resource);
     }
 
     public function testIsClosable()
@@ -59,7 +59,7 @@ public function testIsClosable()
             '/v1/disputes/' . $dispute->id . '/close'
         );
         $resource = $dispute->close();
-        $this->assertInstanceOf("Stripe\\Dispute", $resource);
+        $this->assertInstanceOf(\Stripe\Dispute::class, $resource);
         $this->assertSame($resource, $dispute);
     }
 }
diff --git a/tests/Stripe/EphemeralKeyTest.php b/tests/Stripe/EphemeralKeyTest.php
index e8a1fc0e9..b5196e2a6 100644
--- a/tests/Stripe/EphemeralKeyTest.php
+++ b/tests/Stripe/EphemeralKeyTest.php
@@ -15,7 +15,7 @@ public function testIsCreatable()
         $resource = EphemeralKey::create([
             "customer" => "cus_123",
         ], ["stripe_version" => "2017-05-25"]);
-        $this->assertInstanceOf("Stripe\\EphemeralKey", $resource);
+        $this->assertInstanceOf(\Stripe\EphemeralKey::class, $resource);
     }
 
     /**
@@ -38,6 +38,6 @@ public function testIsDeletable()
             '/v1/ephemeral_keys/' . $key->id
         );
         $resource = $key->delete();
-        $this->assertInstanceOf("Stripe\\EphemeralKey", $resource);
+        $this->assertInstanceOf(\Stripe\EphemeralKey::class, $resource);
     }
 }
diff --git a/tests/Stripe/Error/BaseTest.php b/tests/Stripe/Error/BaseTest.php
index 4c2732ed1..c86d9ab9b 100644
--- a/tests/Stripe/Error/BaseTest.php
+++ b/tests/Stripe/Error/BaseTest.php
@@ -6,7 +6,7 @@ class BaseTest extends TestCase
 {
     public function createFixture($params = [])
     {
-        return $this->getMockForAbstractClass('Stripe\\Error\\Base', [
+        return $this->getMockForAbstractClass(\Stripe\Error\Base::class, [
             'message',
             200,
             '{"key": "value"}',
diff --git a/tests/Stripe/EventTest.php b/tests/Stripe/EventTest.php
index 2e3c92f0e..4fdea6e63 100644
--- a/tests/Stripe/EventTest.php
+++ b/tests/Stripe/EventTest.php
@@ -14,7 +14,7 @@ public function testIsListable()
         );
         $resources = Event::all();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\Event", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\Event::class, $resources->data[0]);
     }
 
     public function testIsRetrievable()
@@ -24,6 +24,6 @@ public function testIsRetrievable()
             '/v1/events/' . self::TEST_RESOURCE_ID
         );
         $resource = Event::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\Event", $resource);
+        $this->assertInstanceOf(\Stripe\Event::class, $resource);
     }
 }
diff --git a/tests/Stripe/FileCreationTest.php b/tests/Stripe/FileCreationTest.php
index 7da79054d..a4bd55e80 100644
--- a/tests/Stripe/FileCreationTest.php
+++ b/tests/Stripe/FileCreationTest.php
@@ -42,7 +42,7 @@ public function testIsCreatableWithFileHandle()
             "file" => $fp,
             "file_link_data" => ["create" => true]
         ]);
-        $this->assertInstanceOf("Stripe\\File", $resource);
+        $this->assertInstanceOf(\Stripe\File::class, $resource);
     }
 
     public function testIsCreatableWithCURLFile()
@@ -61,6 +61,6 @@ public function testIsCreatableWithCURLFile()
             "file" => $curlFile,
             "file_link_data" => ["create" => true]
         ]);
-        $this->assertInstanceOf("Stripe\\File", $resource);
+        $this->assertInstanceOf(\Stripe\File::class, $resource);
     }
 }
diff --git a/tests/Stripe/FileLinkTest.php b/tests/Stripe/FileLinkTest.php
index 264d0f5ee..e70aaf658 100644
--- a/tests/Stripe/FileLinkTest.php
+++ b/tests/Stripe/FileLinkTest.php
@@ -14,7 +14,7 @@ public function testIsListable()
         );
         $resources = FileLink::all();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\FileLink", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\FileLink::class, $resources->data[0]);
     }
 
     public function testIsRetrievable()
@@ -24,7 +24,7 @@ public function testIsRetrievable()
             '/v1/file_links/' . self::TEST_RESOURCE_ID
         );
         $resource = FileLink::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\FileLink", $resource);
+        $this->assertInstanceOf(\Stripe\FileLink::class, $resource);
     }
 
     public function testIsCreatable()
@@ -36,7 +36,7 @@ public function testIsCreatable()
         $resource = FileLink::create([
             "file" => "file_123"
         ]);
-        $this->assertInstanceOf("Stripe\\FileLink", $resource);
+        $this->assertInstanceOf(\Stripe\FileLink::class, $resource);
     }
 
     public function testIsSaveable()
@@ -48,7 +48,7 @@ public function testIsSaveable()
             '/v1/file_links/' . $resource->id
         );
         $resource->save();
-        $this->assertInstanceOf("Stripe\\FileLink", $resource);
+        $this->assertInstanceOf(\Stripe\FileLink::class, $resource);
     }
 
     public function testIsUpdatable()
@@ -60,6 +60,6 @@ public function testIsUpdatable()
         $resource = FileLink::update(self::TEST_RESOURCE_ID, [
             "metadata" => ["key" => "value"],
         ]);
-        $this->assertInstanceOf("Stripe\\FileLink", $resource);
+        $this->assertInstanceOf(\Stripe\FileLink::class, $resource);
     }
 }
diff --git a/tests/Stripe/FileTest.php b/tests/Stripe/FileTest.php
index 5ea89184c..621d2918e 100644
--- a/tests/Stripe/FileTest.php
+++ b/tests/Stripe/FileTest.php
@@ -14,7 +14,7 @@ public function testIsListable()
         );
         $resources = File::all();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\File", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\File::class, $resources->data[0]);
     }
 
     public function testIsRetrievable()
@@ -24,7 +24,7 @@ public function testIsRetrievable()
             '/v1/files/' . self::TEST_RESOURCE_ID
         );
         $resource = File::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\File", $resource);
+        $this->assertInstanceOf(\Stripe\File::class, $resource);
     }
 
     public function testDeserializesFromFile()
@@ -32,7 +32,7 @@ public function testDeserializesFromFile()
         $obj = Util\Util::convertToStripeObject([
             'object' => 'file',
         ], null);
-        $this->assertInstanceOf("Stripe\\File", $obj);
+        $this->assertInstanceOf(\Stripe\File::class, $obj);
     }
 
     public function testDeserializesFromFileUpload()
@@ -40,6 +40,6 @@ public function testDeserializesFromFileUpload()
         $obj = Util\Util::convertToStripeObject([
             'object' => 'file_upload',
         ], null);
-        $this->assertInstanceOf("Stripe\\File", $obj);
+        $this->assertInstanceOf(\Stripe\File::class, $obj);
     }
 }
diff --git a/tests/Stripe/InvoiceItemTest.php b/tests/Stripe/InvoiceItemTest.php
index ffe140aa7..d528da902 100644
--- a/tests/Stripe/InvoiceItemTest.php
+++ b/tests/Stripe/InvoiceItemTest.php
@@ -14,7 +14,7 @@ public function testIsListable()
         );
         $resources = InvoiceItem::all();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\InvoiceItem", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\InvoiceItem::class, $resources->data[0]);
     }
 
     public function testIsRetrievable()
@@ -24,7 +24,7 @@ public function testIsRetrievable()
             '/v1/invoiceitems/' . self::TEST_RESOURCE_ID
         );
         $resource = InvoiceItem::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\InvoiceItem", $resource);
+        $this->assertInstanceOf(\Stripe\InvoiceItem::class, $resource);
     }
 
     public function testIsCreatable()
@@ -38,7 +38,7 @@ public function testIsCreatable()
             "currency" => "usd",
             "customer" => "cus_123"
         ]);
-        $this->assertInstanceOf("Stripe\\InvoiceItem", $resource);
+        $this->assertInstanceOf(\Stripe\InvoiceItem::class, $resource);
     }
 
     public function testIsSaveable()
@@ -50,7 +50,7 @@ public function testIsSaveable()
             '/v1/invoiceitems/' . $resource->id
         );
         $resource->save();
-        $this->assertInstanceOf("Stripe\\InvoiceItem", $resource);
+        $this->assertInstanceOf(\Stripe\InvoiceItem::class, $resource);
     }
 
     public function testIsUpdatable()
@@ -62,7 +62,7 @@ public function testIsUpdatable()
         $resource = InvoiceItem::update(self::TEST_RESOURCE_ID, [
             "metadata" => ["key" => "value"],
         ]);
-        $this->assertInstanceOf("Stripe\\InvoiceItem", $resource);
+        $this->assertInstanceOf(\Stripe\InvoiceItem::class, $resource);
     }
 
     public function testIsDeletable()
@@ -73,6 +73,6 @@ public function testIsDeletable()
             '/v1/invoiceitems/' . $invoiceItem->id
         );
         $resource = $invoiceItem->delete();
-        $this->assertInstanceOf("Stripe\\InvoiceItem", $resource);
+        $this->assertInstanceOf(\Stripe\InvoiceItem::class, $resource);
     }
 }
diff --git a/tests/Stripe/InvoiceTest.php b/tests/Stripe/InvoiceTest.php
index 578b551a1..36c28012e 100644
--- a/tests/Stripe/InvoiceTest.php
+++ b/tests/Stripe/InvoiceTest.php
@@ -14,7 +14,7 @@ public function testIsListable()
         );
         $resources = Invoice::all();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\Invoice", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\Invoice::class, $resources->data[0]);
     }
 
     public function testIsRetrievable()
@@ -24,7 +24,7 @@ public function testIsRetrievable()
             '/v1/invoices/' . self::TEST_RESOURCE_ID
         );
         $resource = Invoice::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\Invoice", $resource);
+        $this->assertInstanceOf(\Stripe\Invoice::class, $resource);
     }
 
     public function testIsCreatable()
@@ -36,7 +36,7 @@ public function testIsCreatable()
         $resource = Invoice::create([
             "customer" => "cus_123"
         ]);
-        $this->assertInstanceOf("Stripe\\Invoice", $resource);
+        $this->assertInstanceOf(\Stripe\Invoice::class, $resource);
     }
 
     public function testIsSaveable()
@@ -48,7 +48,7 @@ public function testIsSaveable()
             '/v1/invoices/' . $resource->id
         );
         $resource->save();
-        $this->assertInstanceOf("Stripe\\Invoice", $resource);
+        $this->assertInstanceOf(\Stripe\Invoice::class, $resource);
     }
 
     public function testIsUpdatable()
@@ -60,7 +60,7 @@ public function testIsUpdatable()
         $resource = Invoice::update(self::TEST_RESOURCE_ID, [
             "metadata" => ["key" => "value"],
         ]);
-        $this->assertInstanceOf("Stripe\\Invoice", $resource);
+        $this->assertInstanceOf(\Stripe\Invoice::class, $resource);
     }
 
     public function testIsDeletable()
@@ -71,7 +71,7 @@ public function testIsDeletable()
             '/v1/invoices/' . self::TEST_RESOURCE_ID
         );
         $resource->delete();
-        $this->assertInstanceOf("Stripe\\Invoice", $resource);
+        $this->assertInstanceOf(\Stripe\Invoice::class, $resource);
     }
 
     public function testCanFinalizeInvoice()
@@ -82,7 +82,7 @@ public function testCanFinalizeInvoice()
             '/v1/invoices/' . $invoice->id . '/finalize'
         );
         $resource = $invoice->finalizeInvoice();
-        $this->assertInstanceOf("Stripe\\Invoice", $resource);
+        $this->assertInstanceOf(\Stripe\Invoice::class, $resource);
         $this->assertSame($resource, $invoice);
     }
 
@@ -94,7 +94,7 @@ public function testCanMarkUncollectible()
             '/v1/invoices/' . $invoice->id . '/mark_uncollectible'
         );
         $resource = $invoice->markUncollectible();
-        $this->assertInstanceOf("Stripe\\Invoice", $resource);
+        $this->assertInstanceOf(\Stripe\Invoice::class, $resource);
         $this->assertSame($resource, $invoice);
     }
 
@@ -106,7 +106,7 @@ public function testCanPay()
             '/v1/invoices/' . $invoice->id . '/pay'
         );
         $resource = $invoice->pay();
-        $this->assertInstanceOf("Stripe\\Invoice", $resource);
+        $this->assertInstanceOf(\Stripe\Invoice::class, $resource);
         $this->assertSame($resource, $invoice);
     }
 
@@ -117,7 +117,7 @@ public function testCanRetrieveUpcoming()
             '/v1/invoices/upcoming'
         );
         $resource = Invoice::upcoming(["customer" => "cus_123"]);
-        $this->assertInstanceOf("Stripe\\Invoice", $resource);
+        $this->assertInstanceOf(\Stripe\Invoice::class, $resource);
     }
 
     public function testCanSendInvoice()
@@ -128,7 +128,7 @@ public function testCanSendInvoice()
             '/v1/invoices/' . $invoice->id . '/send'
         );
         $resource = $invoice->sendInvoice();
-        $this->assertInstanceOf("Stripe\\Invoice", $resource);
+        $this->assertInstanceOf(\Stripe\Invoice::class, $resource);
         $this->assertSame($resource, $invoice);
     }
 
@@ -140,7 +140,7 @@ public function testCanVoidInvoice()
             '/v1/invoices/' . $invoice->id . '/void'
         );
         $resource = $invoice->voidInvoice();
-        $this->assertInstanceOf("Stripe\\Invoice", $resource);
+        $this->assertInstanceOf(\Stripe\Invoice::class, $resource);
         $this->assertSame($resource, $invoice);
     }
 }
diff --git a/tests/Stripe/IssuerFraudRecordTest.php b/tests/Stripe/IssuerFraudRecordTest.php
index 1869248a1..5bcaec745 100644
--- a/tests/Stripe/IssuerFraudRecordTest.php
+++ b/tests/Stripe/IssuerFraudRecordTest.php
@@ -14,7 +14,7 @@ public function testIsListable()
         );
         $resources = IssuerFraudRecord::all();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\IssuerFraudRecord", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\IssuerFraudRecord::class, $resources->data[0]);
     }
 
     public function testIsRetrievable()
@@ -24,6 +24,6 @@ public function testIsRetrievable()
             '/v1/issuer_fraud_records/' . self::TEST_RESOURCE_ID
         );
         $resource = IssuerFraudRecord::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\IssuerFraudRecord", $resource);
+        $this->assertInstanceOf(\Stripe\IssuerFraudRecord::class, $resource);
     }
 }
diff --git a/tests/Stripe/Issuing/AuthorizationTest.php b/tests/Stripe/Issuing/AuthorizationTest.php
index 4bd5480de..956bcdfa9 100644
--- a/tests/Stripe/Issuing/AuthorizationTest.php
+++ b/tests/Stripe/Issuing/AuthorizationTest.php
@@ -14,7 +14,7 @@ public function testIsListable()
         );
         $resources = Authorization::all();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\Issuing\\Authorization", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\Issuing\Authorization::class, $resources->data[0]);
     }
 
     public function testIsRetrievable()
@@ -24,7 +24,7 @@ public function testIsRetrievable()
             '/v1/issuing/authorizations/' . self::TEST_RESOURCE_ID
         );
         $resource = Authorization::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\Issuing\\Authorization", $resource);
+        $this->assertInstanceOf(\Stripe\Issuing\Authorization::class, $resource);
     }
 
     public function testIsSaveable()
@@ -37,7 +37,7 @@ public function testIsSaveable()
             '/v1/issuing/authorizations/' . self::TEST_RESOURCE_ID
         );
         $resource->save();
-        $this->assertInstanceOf("Stripe\\Issuing\\Authorization", $resource);
+        $this->assertInstanceOf(\Stripe\Issuing\Authorization::class, $resource);
     }
 
     public function testIsUpdatable()
@@ -50,7 +50,7 @@ public function testIsUpdatable()
         $resource = Authorization::update(self::TEST_RESOURCE_ID, [
             "metadata" => ["key" => "value"],
         ]);
-        $this->assertInstanceOf("Stripe\\Issuing\\Authorization", $resource);
+        $this->assertInstanceOf(\Stripe\Issuing\Authorization::class, $resource);
     }
 
     public function testIsApprovable()
@@ -62,7 +62,7 @@ public function testIsApprovable()
             '/v1/issuing/authorizations/' . self::TEST_RESOURCE_ID . '/approve'
         );
         $resource = $resource->approve();
-        $this->assertInstanceOf("Stripe\\Issuing\\Authorization", $resource);
+        $this->assertInstanceOf(\Stripe\Issuing\Authorization::class, $resource);
     }
 
     public function testIsDeclinable()
@@ -74,6 +74,6 @@ public function testIsDeclinable()
             '/v1/issuing/authorizations/' . self::TEST_RESOURCE_ID . '/decline'
         );
         $resource = $resource->decline();
-        $this->assertInstanceOf("Stripe\\Issuing\\Authorization", $resource);
+        $this->assertInstanceOf(\Stripe\Issuing\Authorization::class, $resource);
     }
 }
diff --git a/tests/Stripe/Issuing/CardTest.php b/tests/Stripe/Issuing/CardTest.php
index edbe85028..6ad1846cf 100644
--- a/tests/Stripe/Issuing/CardTest.php
+++ b/tests/Stripe/Issuing/CardTest.php
@@ -14,7 +14,7 @@ public function testIsListable()
         );
         $resources = Card::all();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\Issuing\\Card", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\Issuing\Card::class, $resources->data[0]);
     }
 
     public function testIsRetrievable()
@@ -24,7 +24,7 @@ public function testIsRetrievable()
             '/v1/issuing/cards/' . self::TEST_RESOURCE_ID
         );
         $resource = Card::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\Issuing\\Card", $resource);
+        $this->assertInstanceOf(\Stripe\Issuing\Card::class, $resource);
     }
 
     public function testIsSaveable()
@@ -37,7 +37,7 @@ public function testIsSaveable()
             '/v1/issuing/cards/' . self::TEST_RESOURCE_ID
         );
         $resource->save();
-        $this->assertInstanceOf("Stripe\\Issuing\\Card", $resource);
+        $this->assertInstanceOf(\Stripe\Issuing\Card::class, $resource);
     }
 
     public function testIsUpdatable()
@@ -50,7 +50,7 @@ public function testIsUpdatable()
         $resource = Card::update(self::TEST_RESOURCE_ID, [
             "metadata" => ["key" => "value"],
         ]);
-        $this->assertInstanceOf("Stripe\\Issuing\\Card", $resource);
+        $this->assertInstanceOf(\Stripe\Issuing\Card::class, $resource);
     }
 
     public function testCanRetrieveDetails()
@@ -61,6 +61,6 @@ public function testCanRetrieveDetails()
             '/v1/issuing/cards/' . self::TEST_RESOURCE_ID . '/details'
         );
         $details = $resource->details();
-        $this->assertInstanceOf("Stripe\\Issuing\\CardDetails", $details);
+        $this->assertInstanceOf(\Stripe\Issuing\CardDetails::class, $details);
     }
 }
diff --git a/tests/Stripe/Issuing/CardholderTest.php b/tests/Stripe/Issuing/CardholderTest.php
index 8e334e5f8..29a28ed70 100644
--- a/tests/Stripe/Issuing/CardholderTest.php
+++ b/tests/Stripe/Issuing/CardholderTest.php
@@ -27,7 +27,7 @@ public function testIsCreatable()
             $params
         );
         $resource = Cardholder::create($params);
-        $this->assertInstanceOf("Stripe\\Issuing\\Cardholder", $resource);
+        $this->assertInstanceOf(\Stripe\Issuing\Cardholder::class, $resource);
     }
 
     public function testIsListable()
@@ -38,7 +38,7 @@ public function testIsListable()
         );
         $resources = Cardholder::all();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\Issuing\\Cardholder", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\Issuing\Cardholder::class, $resources->data[0]);
     }
 
     public function testIsRetrievable()
@@ -48,7 +48,7 @@ public function testIsRetrievable()
             '/v1/issuing/cardholders/' . self::TEST_RESOURCE_ID
         );
         $resource = Cardholder::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\Issuing\\Cardholder", $resource);
+        $this->assertInstanceOf(\Stripe\Issuing\Cardholder::class, $resource);
     }
 
     public function testIsSaveable()
@@ -61,7 +61,7 @@ public function testIsSaveable()
             '/v1/issuing/cardholders/' . self::TEST_RESOURCE_ID
         );
         $resource->save();
-        $this->assertInstanceOf("Stripe\\Issuing\\Cardholder", $resource);
+        $this->assertInstanceOf(\Stripe\Issuing\Cardholder::class, $resource);
     }
 
     public function testIsUpdatable()
@@ -74,6 +74,6 @@ public function testIsUpdatable()
         $resource = Cardholder::update(self::TEST_RESOURCE_ID, [
             "metadata" => ["key" => "value"],
         ]);
-        $this->assertInstanceOf("Stripe\\Issuing\\Cardholder", $resource);
+        $this->assertInstanceOf(\Stripe\Issuing\Cardholder::class, $resource);
     }
 }
diff --git a/tests/Stripe/Issuing/DisputeTest.php b/tests/Stripe/Issuing/DisputeTest.php
index 068868d30..38e76cc65 100644
--- a/tests/Stripe/Issuing/DisputeTest.php
+++ b/tests/Stripe/Issuing/DisputeTest.php
@@ -19,7 +19,7 @@ public function testIsCreatable()
             $params
         );
         $resource = Dispute::create($params);
-        $this->assertInstanceOf("Stripe\\Issuing\\Dispute", $resource);
+        $this->assertInstanceOf(\Stripe\Issuing\Dispute::class, $resource);
     }
 
     public function testIsListable()
@@ -30,7 +30,7 @@ public function testIsListable()
         );
         $resources = Dispute::all();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\Issuing\\Dispute", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\Issuing\Dispute::class, $resources->data[0]);
     }
 
     public function testIsRetrievable()
@@ -40,7 +40,7 @@ public function testIsRetrievable()
             '/v1/issuing/disputes/' . self::TEST_RESOURCE_ID
         );
         $resource = Dispute::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\Issuing\\Dispute", $resource);
+        $this->assertInstanceOf(\Stripe\Issuing\Dispute::class, $resource);
     }
 
     public function testIsSaveable()
@@ -53,7 +53,7 @@ public function testIsSaveable()
             '/v1/issuing/disputes/' . self::TEST_RESOURCE_ID
         );
         $resource->save();
-        $this->assertInstanceOf("Stripe\\Issuing\\Dispute", $resource);
+        $this->assertInstanceOf(\Stripe\Issuing\Dispute::class, $resource);
     }
 
     public function testIsUpdatable()
@@ -66,6 +66,6 @@ public function testIsUpdatable()
         $resource = Dispute::update(self::TEST_RESOURCE_ID, [
             "metadata" => ["key" => "value"],
         ]);
-        $this->assertInstanceOf("Stripe\\Issuing\\Dispute", $resource);
+        $this->assertInstanceOf(\Stripe\Issuing\Dispute::class, $resource);
     }
 }
diff --git a/tests/Stripe/Issuing/TransactionTest.php b/tests/Stripe/Issuing/TransactionTest.php
index 64d12374a..28978ac68 100644
--- a/tests/Stripe/Issuing/TransactionTest.php
+++ b/tests/Stripe/Issuing/TransactionTest.php
@@ -14,7 +14,7 @@ public function testIsListable()
         );
         $resources = Transaction::all();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\Issuing\\Transaction", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\Issuing\Transaction::class, $resources->data[0]);
     }
 
     public function testIsRetrievable()
@@ -24,7 +24,7 @@ public function testIsRetrievable()
             '/v1/issuing/transactions/' . self::TEST_RESOURCE_ID
         );
         $resource = Transaction::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\Issuing\\Transaction", $resource);
+        $this->assertInstanceOf(\Stripe\Issuing\Transaction::class, $resource);
     }
 
     public function testIsSaveable()
@@ -37,7 +37,7 @@ public function testIsSaveable()
             '/v1/issuing/transactions/' . self::TEST_RESOURCE_ID
         );
         $resource->save();
-        $this->assertInstanceOf("Stripe\\Issuing\\Transaction", $resource);
+        $this->assertInstanceOf(\Stripe\Issuing\Transaction::class, $resource);
     }
 
     public function testIsUpdatable()
@@ -50,6 +50,6 @@ public function testIsUpdatable()
         $resource = Transaction::update(self::TEST_RESOURCE_ID, [
             "metadata" => ["key" => "value"],
         ]);
-        $this->assertInstanceOf("Stripe\\Issuing\\Transaction", $resource);
+        $this->assertInstanceOf(\Stripe\Issuing\Transaction::class, $resource);
     }
 }
diff --git a/tests/Stripe/OrderReturnTest.php b/tests/Stripe/OrderReturnTest.php
index bb2d65c43..c0aa0e115 100644
--- a/tests/Stripe/OrderReturnTest.php
+++ b/tests/Stripe/OrderReturnTest.php
@@ -14,7 +14,7 @@ public function testIsListable()
         );
         $resources = OrderReturn::all();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\OrderReturn", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\OrderReturn::class, $resources->data[0]);
     }
 
     public function testIsRetrievable()
@@ -24,6 +24,6 @@ public function testIsRetrievable()
             '/v1/order_returns/' . self::TEST_RESOURCE_ID
         );
         $resource = OrderReturn::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\OrderReturn", $resource);
+        $this->assertInstanceOf(\Stripe\OrderReturn::class, $resource);
     }
 }
diff --git a/tests/Stripe/OrderTest.php b/tests/Stripe/OrderTest.php
index 51d17e94f..f13ed04b6 100644
--- a/tests/Stripe/OrderTest.php
+++ b/tests/Stripe/OrderTest.php
@@ -14,7 +14,7 @@ public function testIsListable()
         );
         $resources = Order::all();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\Order", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\Order::class, $resources->data[0]);
     }
 
     public function testIsRetrievable()
@@ -24,7 +24,7 @@ public function testIsRetrievable()
             '/v1/orders/' . self::TEST_RESOURCE_ID
         );
         $resource = Order::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\Order", $resource);
+        $this->assertInstanceOf(\Stripe\Order::class, $resource);
     }
 
     public function testIsCreatable()
@@ -36,7 +36,7 @@ public function testIsCreatable()
         $resource = Order::create([
             'currency' => 'usd'
         ]);
-        $this->assertInstanceOf("Stripe\\Order", $resource);
+        $this->assertInstanceOf(\Stripe\Order::class, $resource);
     }
 
     public function testIsSaveable()
@@ -48,7 +48,7 @@ public function testIsSaveable()
             '/v1/orders/' . $resource->id
         );
         $resource->save();
-        $this->assertInstanceOf("Stripe\\Order", $resource);
+        $this->assertInstanceOf(\Stripe\Order::class, $resource);
     }
 
     public function testIsUpdatable()
@@ -60,7 +60,7 @@ public function testIsUpdatable()
         $resource = Order::update(self::TEST_RESOURCE_ID, [
             "metadata" => ["key" => "value"],
         ]);
-        $this->assertInstanceOf("Stripe\\Order", $resource);
+        $this->assertInstanceOf(\Stripe\Order::class, $resource);
     }
 
     public function testIsPayable()
@@ -71,7 +71,7 @@ public function testIsPayable()
             '/v1/orders/' . $resource->id . '/pay'
         );
         $resource->pay();
-        $this->assertInstanceOf("Stripe\\Order", $resource);
+        $this->assertInstanceOf(\Stripe\Order::class, $resource);
     }
 
     public function testIsReturnable()
@@ -82,6 +82,6 @@ public function testIsReturnable()
             '/v1/orders/' . $order->id . '/returns'
         );
         $resource = $order->returnOrder();
-        $this->assertInstanceOf("Stripe\\OrderReturn", $resource);
+        $this->assertInstanceOf(\Stripe\OrderReturn::class, $resource);
     }
 }
diff --git a/tests/Stripe/PaymentIntentTest.php b/tests/Stripe/PaymentIntentTest.php
index 5a883da37..3eaed9a4b 100644
--- a/tests/Stripe/PaymentIntentTest.php
+++ b/tests/Stripe/PaymentIntentTest.php
@@ -14,7 +14,7 @@ public function testIsListable()
         );
         $resources = PaymentIntent::all();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\PaymentIntent", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\PaymentIntent::class, $resources->data[0]);
     }
 
     public function testIsRetrievable()
@@ -24,7 +24,7 @@ public function testIsRetrievable()
             '/v1/payment_intents/' . self::TEST_RESOURCE_ID
         );
         $resource = PaymentIntent::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\PaymentIntent", $resource);
+        $this->assertInstanceOf(\Stripe\PaymentIntent::class, $resource);
     }
 
     public function testIsCreatable()
@@ -38,7 +38,7 @@ public function testIsCreatable()
             "currency" => "usd",
             'payment_method_types' => ['card'],
         ]);
-        $this->assertInstanceOf("Stripe\\PaymentIntent", $resource);
+        $this->assertInstanceOf(\Stripe\PaymentIntent::class, $resource);
     }
 
     public function testIsSaveable()
@@ -50,7 +50,7 @@ public function testIsSaveable()
             '/v1/payment_intents/' . self::TEST_RESOURCE_ID
         );
         $resource->save();
-        $this->assertInstanceOf("Stripe\\PaymentIntent", $resource);
+        $this->assertInstanceOf(\Stripe\PaymentIntent::class, $resource);
     }
 
     public function testIsUpdatable()
@@ -65,7 +65,7 @@ public function testIsUpdatable()
                 "metadata" => ["key" => "value"],
             ]
         );
-        $this->assertInstanceOf("Stripe\\PaymentIntent", $resource);
+        $this->assertInstanceOf(\Stripe\PaymentIntent::class, $resource);
     }
 
     public function testIsCancelable()
@@ -76,7 +76,7 @@ public function testIsCancelable()
             '/v1/payment_intents/' . self::TEST_RESOURCE_ID . '/cancel'
         );
         $resource->cancel();
-        $this->assertInstanceOf("Stripe\\PaymentIntent", $resource);
+        $this->assertInstanceOf(\Stripe\PaymentIntent::class, $resource);
     }
 
     public function testIsCapturable()
@@ -87,7 +87,7 @@ public function testIsCapturable()
             '/v1/payment_intents/' . self::TEST_RESOURCE_ID . '/capture'
         );
         $resource->capture();
-        $this->assertInstanceOf("Stripe\\PaymentIntent", $resource);
+        $this->assertInstanceOf(\Stripe\PaymentIntent::class, $resource);
     }
 
     public function testIsConfirmable()
@@ -98,6 +98,6 @@ public function testIsConfirmable()
             '/v1/payment_intents/' . self::TEST_RESOURCE_ID . '/confirm'
         );
         $resource->confirm();
-        $this->assertInstanceOf("Stripe\\PaymentIntent", $resource);
+        $this->assertInstanceOf(\Stripe\PaymentIntent::class, $resource);
     }
 }
diff --git a/tests/Stripe/PaymentMethodTest.php b/tests/Stripe/PaymentMethodTest.php
index 0280cfb23..89db89af8 100644
--- a/tests/Stripe/PaymentMethodTest.php
+++ b/tests/Stripe/PaymentMethodTest.php
@@ -17,7 +17,7 @@ public function testIsListable()
             'type' => 'card',
         ]);
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\PaymentMethod", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\PaymentMethod::class, $resources->data[0]);
     }
 
     public function testIsRetrievable()
@@ -27,7 +27,7 @@ public function testIsRetrievable()
             '/v1/payment_methods/' . self::TEST_RESOURCE_ID
         );
         $resource = PaymentMethod::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\PaymentMethod", $resource);
+        $this->assertInstanceOf(\Stripe\PaymentMethod::class, $resource);
     }
 
     public function testIsCreatable()
@@ -39,7 +39,7 @@ public function testIsCreatable()
         $resource = PaymentMethod::create([
             'type' => 'card',
         ]);
-        $this->assertInstanceOf("Stripe\\PaymentMethod", $resource);
+        $this->assertInstanceOf(\Stripe\PaymentMethod::class, $resource);
     }
 
     public function testIsSaveable()
@@ -51,7 +51,7 @@ public function testIsSaveable()
             '/v1/payment_methods/' . $resource->id
         );
         $resource->save();
-        $this->assertInstanceOf("Stripe\\PaymentMethod", $resource);
+        $this->assertInstanceOf(\Stripe\PaymentMethod::class, $resource);
     }
 
     public function testIsUpdatable()
@@ -63,7 +63,7 @@ public function testIsUpdatable()
         $resource = PaymentMethod::update(self::TEST_RESOURCE_ID, [
             "metadata" => ["key" => "value"],
         ]);
-        $this->assertInstanceOf("Stripe\\PaymentMethod", $resource);
+        $this->assertInstanceOf(\Stripe\PaymentMethod::class, $resource);
     }
 
     public function testCanAttach()
@@ -76,7 +76,7 @@ public function testCanAttach()
         $resource = $resource->attach([
             'customer' => 'cus_123',
         ]);
-        $this->assertInstanceOf("Stripe\\PaymentMethod", $resource);
+        $this->assertInstanceOf(\Stripe\PaymentMethod::class, $resource);
         $this->assertSame($resource, $resource);
     }
 
@@ -88,7 +88,7 @@ public function testCanDetach()
             '/v1/payment_methods/' . $resource->id . '/detach'
         );
         $resource = $resource->detach();
-        $this->assertInstanceOf("Stripe\\PaymentMethod", $resource);
+        $this->assertInstanceOf(\Stripe\PaymentMethod::class, $resource);
         $this->assertSame($resource, $resource);
     }
 }
diff --git a/tests/Stripe/PayoutTest.php b/tests/Stripe/PayoutTest.php
index 79c7b5fd0..648947636 100644
--- a/tests/Stripe/PayoutTest.php
+++ b/tests/Stripe/PayoutTest.php
@@ -14,7 +14,7 @@ public function testIsListable()
         );
         $resources = Payout::all();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\Payout", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\Payout::class, $resources->data[0]);
     }
 
     public function testIsRetrievable()
@@ -24,7 +24,7 @@ public function testIsRetrievable()
             '/v1/payouts/' . self::TEST_RESOURCE_ID
         );
         $resource = Payout::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\Payout", $resource);
+        $this->assertInstanceOf(\Stripe\Payout::class, $resource);
     }
 
     public function testIsCreatable()
@@ -37,7 +37,7 @@ public function testIsCreatable()
             "amount" => 100,
             "currency" => "usd"
         ]);
-        $this->assertInstanceOf("Stripe\\Payout", $resource);
+        $this->assertInstanceOf(\Stripe\Payout::class, $resource);
     }
 
     public function testIsSaveable()
@@ -49,7 +49,7 @@ public function testIsSaveable()
             '/v1/payouts/' . $resource->id
         );
         $resource->save();
-        $this->assertInstanceOf("Stripe\\Payout", $resource);
+        $this->assertInstanceOf(\Stripe\Payout::class, $resource);
     }
 
     public function testIsUpdatable()
@@ -61,7 +61,7 @@ public function testIsUpdatable()
         $resource = Payout::update(self::TEST_RESOURCE_ID, [
             "metadata" => ["key" => "value"],
         ]);
-        $this->assertInstanceOf("Stripe\\Payout", $resource);
+        $this->assertInstanceOf(\Stripe\Payout::class, $resource);
     }
 
     public function testIsCancelable()
@@ -72,6 +72,6 @@ public function testIsCancelable()
             '/v1/payouts/' . $resource->id . '/cancel'
         );
         $resource->cancel();
-        $this->assertInstanceOf("Stripe\\Payout", $resource);
+        $this->assertInstanceOf(\Stripe\Payout::class, $resource);
     }
 }
diff --git a/tests/Stripe/PersonTest.php b/tests/Stripe/PersonTest.php
index 74c9c3403..fa5a10356 100644
--- a/tests/Stripe/PersonTest.php
+++ b/tests/Stripe/PersonTest.php
@@ -33,7 +33,7 @@ public function testIsSaveable()
             '/v1/accounts/' . self::TEST_ACCOUNT_ID . '/persons/' . self::TEST_RESOURCE_ID
         );
         $resource->save();
-        $this->assertSame("Stripe\\Person", get_class($resource));
+        $this->assertSame(\Stripe\Person::class, get_class($resource));
     }
 
     /**
@@ -54,6 +54,6 @@ public function testIsDeletable()
             '/v1/accounts/' . self::TEST_ACCOUNT_ID . '/persons/' . self::TEST_RESOURCE_ID
         );
         $resource->delete();
-        $this->assertSame("Stripe\\Person", get_class($resource));
+        $this->assertSame(\Stripe\Person::class, get_class($resource));
     }
 }
diff --git a/tests/Stripe/PlanTest.php b/tests/Stripe/PlanTest.php
index 9c33b4174..c87a42429 100644
--- a/tests/Stripe/PlanTest.php
+++ b/tests/Stripe/PlanTest.php
@@ -14,7 +14,7 @@ public function testIsListable()
         );
         $resources = Plan::all();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\Plan", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\Plan::class, $resources->data[0]);
     }
 
     public function testIsRetrievable()
@@ -24,7 +24,7 @@ public function testIsRetrievable()
             '/v1/plans/' . self::TEST_RESOURCE_ID
         );
         $resource = Plan::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\Plan", $resource);
+        $this->assertInstanceOf(\Stripe\Plan::class, $resource);
     }
 
     public function testIsCreatable()
@@ -40,7 +40,7 @@ public function testIsCreatable()
             'nickname' => self::TEST_RESOURCE_ID,
             'id' => self::TEST_RESOURCE_ID
         ]);
-        $this->assertInstanceOf("Stripe\\Plan", $resource);
+        $this->assertInstanceOf(\Stripe\Plan::class, $resource);
     }
 
     public function testIsSaveable()
@@ -52,7 +52,7 @@ public function testIsSaveable()
             '/v1/plans/' . $resource->id
         );
         $resource->save();
-        $this->assertInstanceOf("Stripe\\Plan", $resource);
+        $this->assertInstanceOf(\Stripe\Plan::class, $resource);
     }
 
     public function testIsUpdatable()
@@ -64,7 +64,7 @@ public function testIsUpdatable()
         $resource = Plan::update(self::TEST_RESOURCE_ID, [
             "metadata" => ["key" => "value"],
         ]);
-        $this->assertInstanceOf("Stripe\\Plan", $resource);
+        $this->assertInstanceOf(\Stripe\Plan::class, $resource);
     }
 
     public function testIsDeletable()
@@ -75,6 +75,6 @@ public function testIsDeletable()
             '/v1/plans/' . $resource->id
         );
         $resource->delete();
-        $this->assertInstanceOf("Stripe\\Plan", $resource);
+        $this->assertInstanceOf(\Stripe\Plan::class, $resource);
     }
 }
diff --git a/tests/Stripe/ProductTest.php b/tests/Stripe/ProductTest.php
index c2a3813c8..47854ee33 100644
--- a/tests/Stripe/ProductTest.php
+++ b/tests/Stripe/ProductTest.php
@@ -14,7 +14,7 @@ public function testIsListable()
         );
         $resources = Product::all();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\Product", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\Product::class, $resources->data[0]);
     }
 
     public function testIsRetrievable()
@@ -24,7 +24,7 @@ public function testIsRetrievable()
             '/v1/products/' . self::TEST_RESOURCE_ID
         );
         $resource = Product::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\Product", $resource);
+        $this->assertInstanceOf(\Stripe\Product::class, $resource);
     }
 
     public function testIsCreatable()
@@ -37,7 +37,7 @@ public function testIsCreatable()
             'name' => 'name',
             'type' => 'good'
         ]);
-        $this->assertInstanceOf("Stripe\\Product", $resource);
+        $this->assertInstanceOf(\Stripe\Product::class, $resource);
     }
 
     public function testIsSaveable()
@@ -49,7 +49,7 @@ public function testIsSaveable()
             '/v1/products/' . $resource->id
         );
         $resource->save();
-        $this->assertInstanceOf("Stripe\\Product", $resource);
+        $this->assertInstanceOf(\Stripe\Product::class, $resource);
     }
 
     public function testIsUpdatable()
@@ -61,7 +61,7 @@ public function testIsUpdatable()
         $resource = Product::update(self::TEST_RESOURCE_ID, [
             "metadata" => ["key" => "value"],
         ]);
-        $this->assertInstanceOf("Stripe\\Product", $resource);
+        $this->assertInstanceOf(\Stripe\Product::class, $resource);
     }
 
     public function testIsDeletable()
@@ -72,6 +72,6 @@ public function testIsDeletable()
             '/v1/products/' . $resource->id
         );
         $resource->delete();
-        $this->assertInstanceOf("Stripe\\Product", $resource);
+        $this->assertInstanceOf(\Stripe\Product::class, $resource);
     }
 }
diff --git a/tests/Stripe/Radar/EarlyFraudWarningTest.php b/tests/Stripe/Radar/EarlyFraudWarningTest.php
index 3facf67a9..ac09aec2b 100644
--- a/tests/Stripe/Radar/EarlyFraudWarningTest.php
+++ b/tests/Stripe/Radar/EarlyFraudWarningTest.php
@@ -14,7 +14,7 @@ public function testIsListable()
         );
         $resources = EarlyFraudWarning::all();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\Radar\\EarlyFraudWarning", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\Radar\EarlyFraudWarning::class, $resources->data[0]);
     }
 
     public function testIsRetrievable()
@@ -24,6 +24,6 @@ public function testIsRetrievable()
             '/v1/radar/early_fraud_warnings/' . self::TEST_RESOURCE_ID
         );
         $resource = EarlyFraudWarning::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\Radar\\EarlyFraudWarning", $resource);
+        $this->assertInstanceOf(\Stripe\Radar\EarlyFraudWarning::class, $resource);
     }
 }
diff --git a/tests/Stripe/Radar/ValueListItemTest.php b/tests/Stripe/Radar/ValueListItemTest.php
index 0edb6c137..fdb86342f 100644
--- a/tests/Stripe/Radar/ValueListItemTest.php
+++ b/tests/Stripe/Radar/ValueListItemTest.php
@@ -16,7 +16,7 @@ public function testIsListable()
             "value_list" => "rsl_123",
         ]);
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\Radar\\ValueListItem", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\Radar\ValueListItem::class, $resources->data[0]);
     }
 
     public function testIsRetrievable()
@@ -26,7 +26,7 @@ public function testIsRetrievable()
             '/v1/radar/value_list_items/' . self::TEST_RESOURCE_ID
         );
         $resource = ValueListItem::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\Radar\\ValueListItem", $resource);
+        $this->assertInstanceOf(\Stripe\Radar\ValueListItem::class, $resource);
     }
 
     public function testIsCreatable()
@@ -39,7 +39,7 @@ public function testIsCreatable()
             "value_list" => "rsl_123",
             "value" => "value",
         ]);
-        $this->assertInstanceOf("Stripe\\Radar\\ValueListItem", $resource);
+        $this->assertInstanceOf(\Stripe\Radar\ValueListItem::class, $resource);
     }
 
     public function testIsDeletable()
@@ -50,6 +50,6 @@ public function testIsDeletable()
             '/v1/radar/value_list_items/' . self::TEST_RESOURCE_ID
         );
         $resource->delete();
-        $this->assertInstanceOf("Stripe\\Radar\\ValueListItem", $resource);
+        $this->assertInstanceOf(\Stripe\Radar\ValueListItem::class, $resource);
     }
 }
diff --git a/tests/Stripe/Radar/ValueListTest.php b/tests/Stripe/Radar/ValueListTest.php
index 214e13e90..5c3ef1115 100644
--- a/tests/Stripe/Radar/ValueListTest.php
+++ b/tests/Stripe/Radar/ValueListTest.php
@@ -14,7 +14,7 @@ public function testIsListable()
         );
         $resources = ValueList::all();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\Radar\\ValueList", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\Radar\ValueList::class, $resources->data[0]);
     }
 
     public function testIsRetrievable()
@@ -24,7 +24,7 @@ public function testIsRetrievable()
             '/v1/radar/value_lists/' . self::TEST_RESOURCE_ID
         );
         $resource = ValueList::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\Radar\\ValueList", $resource);
+        $this->assertInstanceOf(\Stripe\Radar\ValueList::class, $resource);
     }
 
     public function testIsCreatable()
@@ -37,7 +37,7 @@ public function testIsCreatable()
             "alias" => "alias",
             "name" => "name",
         ]);
-        $this->assertInstanceOf("Stripe\\Radar\\ValueList", $resource);
+        $this->assertInstanceOf(\Stripe\Radar\ValueList::class, $resource);
     }
 
     public function testIsSaveable()
@@ -49,7 +49,7 @@ public function testIsSaveable()
             '/v1/radar/value_lists/' . self::TEST_RESOURCE_ID
         );
         $resource->save();
-        $this->assertInstanceOf("Stripe\\Radar\\ValueList", $resource);
+        $this->assertInstanceOf(\Stripe\Radar\ValueList::class, $resource);
     }
 
     public function testIsUpdatable()
@@ -61,7 +61,7 @@ public function testIsUpdatable()
         $resource = ValueList::update(self::TEST_RESOURCE_ID, [
             "metadata" => ["key" => "value"],
         ]);
-        $this->assertInstanceOf("Stripe\\Radar\\ValueList", $resource);
+        $this->assertInstanceOf(\Stripe\Radar\ValueList::class, $resource);
     }
 
     public function testIsDeletable()
@@ -72,6 +72,6 @@ public function testIsDeletable()
             '/v1/radar/value_lists/' . self::TEST_RESOURCE_ID
         );
         $resource->delete();
-        $this->assertInstanceOf("Stripe\\Radar\\ValueList", $resource);
+        $this->assertInstanceOf(\Stripe\Radar\ValueList::class, $resource);
     }
 }
diff --git a/tests/Stripe/RecipientTest.php b/tests/Stripe/RecipientTest.php
index 67866721f..cc7f1c7ba 100644
--- a/tests/Stripe/RecipientTest.php
+++ b/tests/Stripe/RecipientTest.php
@@ -14,7 +14,7 @@ public function testIsListable()
         );
         $resources = Recipient::all();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\Recipient", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\Recipient::class, $resources->data[0]);
     }
 
     public function testIsRetrievable()
@@ -24,7 +24,7 @@ public function testIsRetrievable()
             '/v1/recipients/' . self::TEST_RESOURCE_ID
         );
         $resource = Recipient::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\Recipient", $resource);
+        $this->assertInstanceOf(\Stripe\Recipient::class, $resource);
     }
 
     public function testIsCreatable()
@@ -37,7 +37,7 @@ public function testIsCreatable()
             "name" => "name",
             "type" => "individual"
         ]);
-        $this->assertInstanceOf("Stripe\\Recipient", $resource);
+        $this->assertInstanceOf(\Stripe\Recipient::class, $resource);
     }
 
     public function testIsSaveable()
@@ -49,7 +49,7 @@ public function testIsSaveable()
             '/v1/recipients/' . $resource->id
         );
         $resource->save();
-        $this->assertInstanceOf("Stripe\\Recipient", $resource);
+        $this->assertInstanceOf(\Stripe\Recipient::class, $resource);
     }
 
     public function testIsUpdatable()
@@ -61,7 +61,7 @@ public function testIsUpdatable()
         $resource = Recipient::update(self::TEST_RESOURCE_ID, [
             "metadata" => ["key" => "value"],
         ]);
-        $this->assertInstanceOf("Stripe\\Recipient", $resource);
+        $this->assertInstanceOf(\Stripe\Recipient::class, $resource);
     }
 
     public function testIsDeletable()
@@ -72,7 +72,7 @@ public function testIsDeletable()
             '/v1/recipients/' . $resource->id
         );
         $resource->delete();
-        $this->assertInstanceOf("Stripe\\Recipient", $resource);
+        $this->assertInstanceOf(\Stripe\Recipient::class, $resource);
     }
 
     public function testCanListTransfers()
@@ -93,6 +93,6 @@ public function testCanListTransfers()
         );
         $resources = $recipient->transfers();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\Transfer", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\Transfer::class, $resources->data[0]);
     }
 }
diff --git a/tests/Stripe/RefundTest.php b/tests/Stripe/RefundTest.php
index 788361d4d..96e8e6ed1 100644
--- a/tests/Stripe/RefundTest.php
+++ b/tests/Stripe/RefundTest.php
@@ -14,7 +14,7 @@ public function testIsListable()
         );
         $resources = Refund::all();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\Refund", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\Refund::class, $resources->data[0]);
     }
 
     public function testIsRetrievable()
@@ -24,7 +24,7 @@ public function testIsRetrievable()
             '/v1/refunds/' . self::TEST_RESOURCE_ID
         );
         $resource = Refund::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\Refund", $resource);
+        $this->assertInstanceOf(\Stripe\Refund::class, $resource);
     }
 
     public function testIsCreatable()
@@ -36,7 +36,7 @@ public function testIsCreatable()
         $resource = Refund::create([
             "charge" => "ch_123"
         ]);
-        $this->assertInstanceOf("Stripe\\Refund", $resource);
+        $this->assertInstanceOf(\Stripe\Refund::class, $resource);
     }
 
     public function testIsSaveable()
@@ -48,7 +48,7 @@ public function testIsSaveable()
             '/v1/refunds/' . $resource->id
         );
         $resource->save();
-        $this->assertInstanceOf("Stripe\\Refund", $resource);
+        $this->assertInstanceOf(\Stripe\Refund::class, $resource);
     }
 
     public function testIsUpdatable()
@@ -60,6 +60,6 @@ public function testIsUpdatable()
         $resource = Refund::update(self::TEST_RESOURCE_ID, [
             "metadata" => ["key" => "value"],
         ]);
-        $this->assertInstanceOf("Stripe\\Refund", $resource);
+        $this->assertInstanceOf(\Stripe\Refund::class, $resource);
     }
 }
diff --git a/tests/Stripe/Reporting/ReportRunTest.php b/tests/Stripe/Reporting/ReportRunTest.php
index a78070405..788f2379d 100644
--- a/tests/Stripe/Reporting/ReportRunTest.php
+++ b/tests/Stripe/Reporting/ReportRunTest.php
@@ -21,7 +21,7 @@ public function testIsCreatable()
             $params
         );
         $resource = ReportRun::create($params);
-        $this->assertInstanceOf("Stripe\\Reporting\\ReportRun", $resource);
+        $this->assertInstanceOf(\Stripe\Reporting\ReportRun::class, $resource);
     }
 
     public function testIsListable()
@@ -32,7 +32,7 @@ public function testIsListable()
         );
         $resources = ReportRun::all();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\Reporting\\ReportRun", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\Reporting\ReportRun::class, $resources->data[0]);
     }
 
     public function testIsRetrievable()
@@ -42,6 +42,6 @@ public function testIsRetrievable()
             '/v1/reporting/report_runs/' . self::TEST_RESOURCE_ID
         );
         $resource = ReportRun::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\Reporting\\ReportRun", $resource);
+        $this->assertInstanceOf(\Stripe\Reporting\ReportRun::class, $resource);
     }
 }
diff --git a/tests/Stripe/Reporting/ReportTypeTest.php b/tests/Stripe/Reporting/ReportTypeTest.php
index d37778502..43d1a91cd 100644
--- a/tests/Stripe/Reporting/ReportTypeTest.php
+++ b/tests/Stripe/Reporting/ReportTypeTest.php
@@ -14,7 +14,7 @@ public function testIsListable()
         );
         $resources = ReportType::all();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\Reporting\\ReportType", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\Reporting\ReportType::class, $resources->data[0]);
     }
 
     public function testIsRetrievable()
@@ -24,6 +24,6 @@ public function testIsRetrievable()
             '/v1/reporting/report_types/' . self::TEST_RESOURCE_ID
         );
         $resource = ReportType::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\Reporting\\ReportType", $resource);
+        $this->assertInstanceOf(\Stripe\Reporting\ReportType::class, $resource);
     }
 }
diff --git a/tests/Stripe/ReviewTest.php b/tests/Stripe/ReviewTest.php
index 7c82c21c0..82b9673de 100644
--- a/tests/Stripe/ReviewTest.php
+++ b/tests/Stripe/ReviewTest.php
@@ -14,7 +14,7 @@ public function testIsApprovable()
             '/v1/reviews/' . self::TEST_RESOURCE_ID . '/approve'
         );
         $resource->approve();
-        $this->assertInstanceOf("Stripe\\Review", $resource);
+        $this->assertInstanceOf(\Stripe\Review::class, $resource);
     }
 
     public function testIsListable()
@@ -25,7 +25,7 @@ public function testIsListable()
         );
         $resources = Review::all();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\Review", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\Review::class, $resources->data[0]);
     }
 
     public function testIsRetrievable()
@@ -35,6 +35,6 @@ public function testIsRetrievable()
             '/v1/reviews/' . self::TEST_RESOURCE_ID
         );
         $resource = Review::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\Review", $resource);
+        $this->assertInstanceOf(\Stripe\Review::class, $resource);
     }
 }
diff --git a/tests/Stripe/SKUTest.php b/tests/Stripe/SKUTest.php
index d4fc2ad40..584c37cfe 100644
--- a/tests/Stripe/SKUTest.php
+++ b/tests/Stripe/SKUTest.php
@@ -14,7 +14,7 @@ public function testIsListable()
         );
         $resources = SKU::all();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\SKU", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\SKU::class, $resources->data[0]);
     }
 
     public function testIsRetrievable()
@@ -24,7 +24,7 @@ public function testIsRetrievable()
             '/v1/skus/' . self::TEST_RESOURCE_ID
         );
         $resource = SKU::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\SKU", $resource);
+        $this->assertInstanceOf(\Stripe\SKU::class, $resource);
     }
 
     public function testIsCreatable()
@@ -42,7 +42,7 @@ public function testIsCreatable()
             'price'     => 100,
             'product'   => "prod_123"
         ]);
-        $this->assertInstanceOf("Stripe\\SKU", $resource);
+        $this->assertInstanceOf(\Stripe\SKU::class, $resource);
     }
 
     public function testIsSaveable()
@@ -54,7 +54,7 @@ public function testIsSaveable()
             '/v1/skus/' . $resource->id
         );
         $resource->save();
-        $this->assertInstanceOf("Stripe\\SKU", $resource);
+        $this->assertInstanceOf(\Stripe\SKU::class, $resource);
     }
 
     public function testIsUpdatable()
@@ -66,7 +66,7 @@ public function testIsUpdatable()
         $resource = SKU::update(self::TEST_RESOURCE_ID, [
             "metadata" => ["key" => "value"],
         ]);
-        $this->assertInstanceOf("Stripe\\SKU", $resource);
+        $this->assertInstanceOf(\Stripe\SKU::class, $resource);
     }
 
     public function testIsDeletable()
@@ -77,6 +77,6 @@ public function testIsDeletable()
             '/v1/skus/' . $resource->id
         );
         $resource->delete();
-        $this->assertInstanceOf("Stripe\\SKU", $resource);
+        $this->assertInstanceOf(\Stripe\SKU::class, $resource);
     }
 }
diff --git a/tests/Stripe/SetupIntentTest.php b/tests/Stripe/SetupIntentTest.php
index d6361413d..65b207934 100644
--- a/tests/Stripe/SetupIntentTest.php
+++ b/tests/Stripe/SetupIntentTest.php
@@ -14,7 +14,7 @@ public function testIsListable()
         );
         $resources = SetupIntent::all();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\SetupIntent", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\SetupIntent::class, $resources->data[0]);
     }
 
     public function testIsRetrievable()
@@ -24,7 +24,7 @@ public function testIsRetrievable()
             '/v1/setup_intents/' . self::TEST_RESOURCE_ID
         );
         $resource = SetupIntent::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\SetupIntent", $resource);
+        $this->assertInstanceOf(\Stripe\SetupIntent::class, $resource);
     }
 
     public function testIsCreatable()
@@ -36,7 +36,7 @@ public function testIsCreatable()
         $resource = SetupIntent::create([
             'payment_method_types' => ['card'],
         ]);
-        $this->assertInstanceOf("Stripe\\SetupIntent", $resource);
+        $this->assertInstanceOf(\Stripe\SetupIntent::class, $resource);
     }
 
     public function testIsSaveable()
@@ -48,7 +48,7 @@ public function testIsSaveable()
             '/v1/setup_intents/' . self::TEST_RESOURCE_ID
         );
         $resource->save();
-        $this->assertInstanceOf("Stripe\\SetupIntent", $resource);
+        $this->assertInstanceOf(\Stripe\SetupIntent::class, $resource);
     }
 
     public function testIsUpdatable()
@@ -63,7 +63,7 @@ public function testIsUpdatable()
                 "metadata" => ["key" => "value"],
             ]
         );
-        $this->assertInstanceOf("Stripe\\SetupIntent", $resource);
+        $this->assertInstanceOf(\Stripe\SetupIntent::class, $resource);
     }
 
     public function testIsCancelable()
@@ -74,7 +74,7 @@ public function testIsCancelable()
             '/v1/setup_intents/' . self::TEST_RESOURCE_ID . '/cancel'
         );
         $resource->cancel();
-        $this->assertInstanceOf("Stripe\\SetupIntent", $resource);
+        $this->assertInstanceOf(\Stripe\SetupIntent::class, $resource);
     }
 
     public function testIsConfirmable()
@@ -85,6 +85,6 @@ public function testIsConfirmable()
             '/v1/setup_intents/' . self::TEST_RESOURCE_ID . '/confirm'
         );
         $resource->confirm();
-        $this->assertInstanceOf("Stripe\\SetupIntent", $resource);
+        $this->assertInstanceOf(\Stripe\SetupIntent::class, $resource);
     }
 }
diff --git a/tests/Stripe/Sigma/ScheduledQueryRunTest.php b/tests/Stripe/Sigma/ScheduledQueryRunTest.php
index f79e230bc..fd2cf01ca 100644
--- a/tests/Stripe/Sigma/ScheduledQueryRunTest.php
+++ b/tests/Stripe/Sigma/ScheduledQueryRunTest.php
@@ -10,12 +10,12 @@ public function testIsListable()
     {
         $resources = ScheduledQueryRun::all();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\Sigma\\ScheduledQueryRun", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\Sigma\ScheduledQueryRun::class, $resources->data[0]);
     }
 
     public function testIsRetrievable()
     {
         $resource = ScheduledQueryRun::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\Sigma\\ScheduledQueryRun", $resource);
+        $this->assertInstanceOf(\Stripe\Sigma\ScheduledQueryRun::class, $resource);
     }
 }
diff --git a/tests/Stripe/SourceTest.php b/tests/Stripe/SourceTest.php
index ad11b0d34..04efc8e02 100644
--- a/tests/Stripe/SourceTest.php
+++ b/tests/Stripe/SourceTest.php
@@ -13,7 +13,7 @@ public function testIsRetrievable()
             '/v1/sources/' . self::TEST_RESOURCE_ID
         );
         $resource = Source::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\Source", $resource);
+        $this->assertInstanceOf(\Stripe\Source::class, $resource);
     }
 
     public function testIsCreatable()
@@ -25,7 +25,7 @@ public function testIsCreatable()
         $resource = Source::create([
             "type" => "card"
         ]);
-        $this->assertInstanceOf("Stripe\\Source", $resource);
+        $this->assertInstanceOf(\Stripe\Source::class, $resource);
     }
 
     public function testIsSaveable()
@@ -37,7 +37,7 @@ public function testIsSaveable()
             '/v1/sources/' . $resource->id
         );
         $resource->save();
-        $this->assertInstanceOf("Stripe\\Source", $resource);
+        $this->assertInstanceOf(\Stripe\Source::class, $resource);
     }
 
     public function testIsUpdatable()
@@ -49,7 +49,7 @@ public function testIsUpdatable()
         $resource = Source::update(self::TEST_RESOURCE_ID, [
             "metadata" => ["key" => "value"],
         ]);
-        $this->assertInstanceOf("Stripe\\Source", $resource);
+        $this->assertInstanceOf(\Stripe\Source::class, $resource);
     }
 
     public function testCanSaveCardExpiryDate()
@@ -97,7 +97,7 @@ public function testIsDetachableWhenAttached()
             '/v1/customers/cus_123/sources/' . $resource->id
         );
         $resource->delete();
-        $this->assertInstanceOf("Stripe\\Source", $resource);
+        $this->assertInstanceOf(\Stripe\Source::class, $resource);
     }
 
     /**
@@ -118,7 +118,7 @@ public function testCanListSourceTransactions()
         );
         $resources = $source->sourceTransactions();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\SourceTransaction", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\SourceTransaction::class, $resources->data[0]);
     }
 
     public function testCanVerify()
@@ -129,6 +129,6 @@ public function testCanVerify()
             '/v1/sources/' . $resource->id . "/verify"
         );
         $resource->verify(["values" => [32, 45]]);
-        $this->assertInstanceOf("Stripe\\Source", $resource);
+        $this->assertInstanceOf(\Stripe\Source::class, $resource);
     }
 }
diff --git a/tests/Stripe/StripeObjectTest.php b/tests/Stripe/StripeObjectTest.php
index bbf2d7c5a..9f245afa8 100644
--- a/tests/Stripe/StripeObjectTest.php
+++ b/tests/Stripe/StripeObjectTest.php
@@ -13,11 +13,11 @@ public function setUpReflectors()
         // private attributes.
 
         // This is used to invoke the `deepCopy` protected function
-        $this->deepCopyReflector = new \ReflectionMethod('Stripe\\StripeObject', 'deepCopy');
+        $this->deepCopyReflector = new \ReflectionMethod(\Stripe\StripeObject::class, 'deepCopy');
         $this->deepCopyReflector->setAccessible(true);
 
         // This is used to access the `_opts` protected variable
-        $this->optsReflector = new \ReflectionProperty('Stripe\\StripeObject', '_opts');
+        $this->optsReflector = new \ReflectionProperty(\Stripe\StripeObject::class, '_opts');
         $this->optsReflector->setAccessible(true);
     }
 
@@ -480,7 +480,7 @@ public function testDeserializeEmptyMetadata()
             'metadata' => [],
         ]);
 
-        $this->assertInstanceOf("Stripe\\StripeObject", $obj->metadata);
+        $this->assertInstanceOf(\Stripe\StripeObject::class, $obj->metadata);
     }
 
     public function testDeserializeMetadataWithKeyNamedMetadata()
@@ -489,7 +489,7 @@ public function testDeserializeMetadataWithKeyNamedMetadata()
             'metadata' => ['metadata' => 'value'],
         ]);
 
-        $this->assertInstanceOf("Stripe\\StripeObject", $obj->metadata);
+        $this->assertInstanceOf(\Stripe\StripeObject::class, $obj->metadata);
         $this->assertEquals("value", $obj->metadata->metadata);
     }
 }
diff --git a/tests/Stripe/SubscriptionItemTest.php b/tests/Stripe/SubscriptionItemTest.php
index 2432820fd..15a496c65 100644
--- a/tests/Stripe/SubscriptionItemTest.php
+++ b/tests/Stripe/SubscriptionItemTest.php
@@ -19,7 +19,7 @@ public function testIsListable()
             "subscription" => "sub_123"
         ]);
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\SubscriptionItem", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\SubscriptionItem::class, $resources->data[0]);
     }
 
     public function testIsRetrievable()
@@ -29,7 +29,7 @@ public function testIsRetrievable()
             '/v1/subscription_items/' . self::TEST_RESOURCE_ID
         );
         $resource = SubscriptionItem::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\SubscriptionItem", $resource);
+        $this->assertInstanceOf(\Stripe\SubscriptionItem::class, $resource);
     }
 
     public function testIsCreatable()
@@ -42,7 +42,7 @@ public function testIsCreatable()
             "plan" => "plan",
             "subscription" => "sub_123"
         ]);
-        $this->assertInstanceOf("Stripe\\SubscriptionItem", $resource);
+        $this->assertInstanceOf(\Stripe\SubscriptionItem::class, $resource);
     }
 
     public function testIsSaveable()
@@ -54,7 +54,7 @@ public function testIsSaveable()
             '/v1/subscription_items/' . $resource->id
         );
         $resource->save();
-        $this->assertInstanceOf("Stripe\\SubscriptionItem", $resource);
+        $this->assertInstanceOf(\Stripe\SubscriptionItem::class, $resource);
     }
 
     public function testIsUpdatable()
@@ -66,7 +66,7 @@ public function testIsUpdatable()
         $resource = SubscriptionItem::update(self::TEST_RESOURCE_ID, [
             "metadata" => ["key" => "value"],
         ]);
-        $this->assertInstanceOf("Stripe\\SubscriptionItem", $resource);
+        $this->assertInstanceOf(\Stripe\SubscriptionItem::class, $resource);
     }
 
     public function testIsDeletable()
@@ -77,7 +77,7 @@ public function testIsDeletable()
             '/v1/subscription_items/' . $resource->id
         );
         $resource->delete();
-        $this->assertInstanceOf("Stripe\\SubscriptionItem", $resource);
+        $this->assertInstanceOf(\Stripe\SubscriptionItem::class, $resource);
     }
 
     public function testCanListUsageRecordSummaries()
@@ -89,6 +89,6 @@ public function testCanListUsageRecordSummaries()
         );
         $resources = $resource->usageRecordSummaries();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\UsageRecordSummary", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\UsageRecordSummary::class, $resources->data[0]);
     }
 }
diff --git a/tests/Stripe/SubscriptionScheduleTest.php b/tests/Stripe/SubscriptionScheduleTest.php
index c6b20cc6d..9b4c5e3bf 100644
--- a/tests/Stripe/SubscriptionScheduleTest.php
+++ b/tests/Stripe/SubscriptionScheduleTest.php
@@ -15,7 +15,7 @@ public function testIsListable()
         );
         $resources = SubscriptionSchedule::all();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\SubscriptionSchedule", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\SubscriptionSchedule::class, $resources->data[0]);
     }
 
     public function testIsRetrievable()
@@ -25,7 +25,7 @@ public function testIsRetrievable()
             '/v1/subscription_schedules/' . self::TEST_RESOURCE_ID
         );
         $resource = SubscriptionSchedule::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\SubscriptionSchedule", $resource);
+        $this->assertInstanceOf(\Stripe\SubscriptionSchedule::class, $resource);
     }
 
     public function testIsCreatable()
@@ -43,7 +43,7 @@ public function testIsCreatable()
                 ],
             ],
         ]);
-        $this->assertInstanceOf("Stripe\\SubscriptionSchedule", $resource);
+        $this->assertInstanceOf(\Stripe\SubscriptionSchedule::class, $resource);
     }
 
     public function testIsSaveable()
@@ -55,7 +55,7 @@ public function testIsSaveable()
             '/v1/subscription_schedules/' . $resource->id
         );
         $resource->save();
-        $this->assertInstanceOf("Stripe\\SubscriptionSchedule", $resource);
+        $this->assertInstanceOf(\Stripe\SubscriptionSchedule::class, $resource);
     }
 
     public function testIsUpdatable()
@@ -67,7 +67,7 @@ public function testIsUpdatable()
         $resource = SubscriptionSchedule::update(self::TEST_RESOURCE_ID, [
             "metadata" => ["key" => "value"],
         ]);
-        $this->assertInstanceOf("Stripe\\SubscriptionSchedule", $resource);
+        $this->assertInstanceOf(\Stripe\SubscriptionSchedule::class, $resource);
     }
 
     public function testIsCancelable()
@@ -79,7 +79,7 @@ public function testIsCancelable()
             []
         );
         $resource->cancel([]);
-        $this->assertInstanceOf("Stripe\\SubscriptionSchedule", $resource);
+        $this->assertInstanceOf(\Stripe\SubscriptionSchedule::class, $resource);
     }
 
     public function testIsReleaseable()
@@ -91,7 +91,7 @@ public function testIsReleaseable()
             []
         );
         $resource->release([]);
-        $this->assertInstanceOf("Stripe\\SubscriptionSchedule", $resource);
+        $this->assertInstanceOf(\Stripe\SubscriptionSchedule::class, $resource);
     }
 
     public function testRevisions()
@@ -103,7 +103,7 @@ public function testRevisions()
         );
         $revisions = $schedule->revisions();
         $this->assertTrue(is_array($revisions->data));
-        $this->assertInstanceOf("Stripe\\SubscriptionScheduleRevision", $revisions->data[0]);
+        $this->assertInstanceOf(\Stripe\SubscriptionScheduleRevision::class, $revisions->data[0]);
     }
 
     public function testCanRetrieveRevision()
@@ -113,7 +113,7 @@ public function testCanRetrieveRevision()
             '/v1/subscription_schedules/' . self::TEST_RESOURCE_ID . '/revisions/' . self::TEST_REVISION_ID
         );
         $resource = SubscriptionSchedule::retrieveRevision(self::TEST_RESOURCE_ID, self::TEST_REVISION_ID);
-        $this->assertInstanceOf("Stripe\\SubscriptionScheduleRevision", $resource);
+        $this->assertInstanceOf(\Stripe\SubscriptionScheduleRevision::class, $resource);
     }
 
     public function testCanListRevisions()
diff --git a/tests/Stripe/SubscriptionTest.php b/tests/Stripe/SubscriptionTest.php
index 59b92e8fc..422056201 100644
--- a/tests/Stripe/SubscriptionTest.php
+++ b/tests/Stripe/SubscriptionTest.php
@@ -14,7 +14,7 @@ public function testIsListable()
         );
         $resources = Subscription::all();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\Subscription", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\Subscription::class, $resources->data[0]);
     }
 
     public function testIsRetrievable()
@@ -24,7 +24,7 @@ public function testIsRetrievable()
             '/v1/subscriptions/' . self::TEST_RESOURCE_ID
         );
         $resource = Subscription::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\Subscription", $resource);
+        $this->assertInstanceOf(\Stripe\Subscription::class, $resource);
     }
 
     public function testIsCreatable()
@@ -36,7 +36,7 @@ public function testIsCreatable()
         $resource = Subscription::create([
             "customer" => "cus_123"
         ]);
-        $this->assertInstanceOf("Stripe\\Subscription", $resource);
+        $this->assertInstanceOf(\Stripe\Subscription::class, $resource);
     }
 
     public function testIsSaveable()
@@ -48,7 +48,7 @@ public function testIsSaveable()
             '/v1/subscriptions/' . $resource->id
         );
         $resource->save();
-        $this->assertInstanceOf("Stripe\\Subscription", $resource);
+        $this->assertInstanceOf(\Stripe\Subscription::class, $resource);
     }
 
     public function testIsUpdatable()
@@ -60,7 +60,7 @@ public function testIsUpdatable()
         $resource = Subscription::update(self::TEST_RESOURCE_ID, [
             "metadata" => ["key" => "value"],
         ]);
-        $this->assertInstanceOf("Stripe\\Subscription", $resource);
+        $this->assertInstanceOf(\Stripe\Subscription::class, $resource);
     }
 
     public function testIsCancelable()
@@ -72,7 +72,7 @@ public function testIsCancelable()
             []
         );
         $resource->cancel([]);
-        $this->assertInstanceOf("Stripe\\Subscription", $resource);
+        $this->assertInstanceOf(\Stripe\Subscription::class, $resource);
     }
 
     public function testCanDeleteDiscount()
@@ -83,7 +83,7 @@ public function testCanDeleteDiscount()
             '/v1/subscriptions/' . $resource->id . '/discount'
         );
         $resource->deleteDiscount();
-        $this->assertInstanceOf("Stripe\\Subscription", $resource);
+        $this->assertInstanceOf(\Stripe\Subscription::class, $resource);
     }
 
     public function testSerializeParametersItems()
diff --git a/tests/Stripe/TaxIdTest.php b/tests/Stripe/TaxIdTest.php
index f482c7a10..3040d3b0e 100644
--- a/tests/Stripe/TaxIdTest.php
+++ b/tests/Stripe/TaxIdTest.php
@@ -24,6 +24,6 @@ public function testIsDeletable()
             '/v1/customers/' . self::TEST_CUSTOMER_ID . '/tax_ids/' . self::TEST_RESOURCE_ID
         );
         $resource->delete();
-        $this->assertSame("Stripe\\TaxId", get_class($resource));
+        $this->assertInstanceOf(\Stripe\TaxId::class, $resource);
     }
 }
diff --git a/tests/Stripe/TaxRateTest.php b/tests/Stripe/TaxRateTest.php
index 69be07148..737f09f25 100644
--- a/tests/Stripe/TaxRateTest.php
+++ b/tests/Stripe/TaxRateTest.php
@@ -14,7 +14,7 @@ public function testIsListable()
         );
         $resources = TaxRate::all();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\TaxRate", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\TaxRate::class, $resources->data[0]);
     }
 
     public function testIsRetrievable()
@@ -24,7 +24,7 @@ public function testIsRetrievable()
             '/v1/tax_rates/' . self::TEST_RESOURCE_ID
         );
         $resource = TaxRate::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\TaxRate", $resource);
+        $this->assertInstanceOf(\Stripe\TaxRate::class, $resource);
     }
 
     public function testIsCreatable()
@@ -38,7 +38,7 @@ public function testIsCreatable()
             "inclusive" => false,
             "percentage" => 10.15,
         ]);
-        $this->assertInstanceOf("Stripe\\TaxRate", $resource);
+        $this->assertInstanceOf(\Stripe\TaxRate::class, $resource);
     }
 
     public function testIsSaveable()
@@ -50,7 +50,7 @@ public function testIsSaveable()
             '/v1/tax_rates/' . self::TEST_RESOURCE_ID
         );
         $resource->save();
-        $this->assertInstanceOf("Stripe\\TaxRate", $resource);
+        $this->assertInstanceOf(\Stripe\TaxRate::class, $resource);
     }
 
     public function testIsUpdatable()
@@ -62,6 +62,6 @@ public function testIsUpdatable()
         $resource = TaxRate::update(self::TEST_RESOURCE_ID, [
             "metadata" => ["key" => "value"],
         ]);
-        $this->assertInstanceOf("Stripe\\TaxRate", $resource);
+        $this->assertInstanceOf(\Stripe\TaxRate::class, $resource);
     }
 }
diff --git a/tests/Stripe/Terminal/ConnectionTokenTest.php b/tests/Stripe/Terminal/ConnectionTokenTest.php
index bbb1609f5..9283b6d98 100644
--- a/tests/Stripe/Terminal/ConnectionTokenTest.php
+++ b/tests/Stripe/Terminal/ConnectionTokenTest.php
@@ -11,6 +11,6 @@ public function testIsCreatable()
             '/v1/terminal/connection_tokens'
         );
         $resource = ConnectionToken::create();
-        $this->assertInstanceOf("Stripe\\Terminal\\ConnectionToken", $resource);
+        $this->assertInstanceOf(\Stripe\Terminal\ConnectionToken::class, $resource);
     }
 }
diff --git a/tests/Stripe/Terminal/LocationTest.php b/tests/Stripe/Terminal/LocationTest.php
index 232e45beb..1d20b1d31 100644
--- a/tests/Stripe/Terminal/LocationTest.php
+++ b/tests/Stripe/Terminal/LocationTest.php
@@ -14,7 +14,7 @@ public function testIsListable()
         );
         $resources = Location::all();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\Terminal\\Location", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\Terminal\Location::class, $resources->data[0]);
     }
 
     public function testIsRetrievable()
@@ -24,7 +24,7 @@ public function testIsRetrievable()
             '/v1/terminal/locations/' . self::TEST_RESOURCE_ID
         );
         $resource = Location::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\Terminal\\Location", $resource);
+        $this->assertInstanceOf(\Stripe\Terminal\Location::class, $resource);
     }
 
     public function testIsSaveable()
@@ -37,7 +37,7 @@ public function testIsSaveable()
             '/v1/terminal/locations/' . self::TEST_RESOURCE_ID
         );
         $resource->save();
-        $this->assertInstanceOf("Stripe\\Terminal\\Location", $resource);
+        $this->assertInstanceOf(\Stripe\Terminal\Location::class, $resource);
     }
 
     public function testIsUpdatable()
@@ -50,7 +50,7 @@ public function testIsUpdatable()
         $resource = Location::update(self::TEST_RESOURCE_ID, [
             "display_name" => "new-name",
         ]);
-        $this->assertInstanceOf("Stripe\\Terminal\\Location", $resource);
+        $this->assertInstanceOf(\Stripe\Terminal\Location::class, $resource);
     }
 
     public function testIsCreatable()
@@ -79,7 +79,7 @@ public function testIsCreatable()
                 "city" => "San Francisco"
             ]
         ]);
-        $this->assertInstanceOf("Stripe\\Terminal\\Location", $resource);
+        $this->assertInstanceOf(\Stripe\Terminal\Location::class, $resource);
     }
 
     public function testIsDeletable()
@@ -90,6 +90,6 @@ public function testIsDeletable()
             '/v1/terminal/locations/' . self::TEST_RESOURCE_ID
         );
         $resource->delete();
-        $this->assertInstanceOf("Stripe\\Terminal\\Location", $resource);
+        $this->assertInstanceOf(\Stripe\Terminal\Location::class, $resource);
     }
 }
diff --git a/tests/Stripe/Terminal/ReaderTest.php b/tests/Stripe/Terminal/ReaderTest.php
index 43bbb8f3b..882cc1429 100644
--- a/tests/Stripe/Terminal/ReaderTest.php
+++ b/tests/Stripe/Terminal/ReaderTest.php
@@ -14,7 +14,7 @@ public function testIsListable()
         );
         $resources = Reader::all();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\Terminal\\Reader", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\Terminal\Reader::class, $resources->data[0]);
     }
 
     public function testIsRetrievable()
@@ -24,7 +24,7 @@ public function testIsRetrievable()
             '/v1/terminal/readers/' . self::TEST_RESOURCE_ID
         );
         $resource = Reader::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\Terminal\\Reader", $resource);
+        $this->assertInstanceOf(\Stripe\Terminal\Reader::class, $resource);
     }
 
     public function testIsSaveable()
@@ -37,7 +37,7 @@ public function testIsSaveable()
             '/v1/terminal/readers/' . self::TEST_RESOURCE_ID
         );
         $resource->save();
-        $this->assertInstanceOf("Stripe\\Terminal\\Reader", $resource);
+        $this->assertInstanceOf(\Stripe\Terminal\Reader::class, $resource);
     }
 
     public function testIsUpdatable()
@@ -50,7 +50,7 @@ public function testIsUpdatable()
         $resource = Reader::update(self::TEST_RESOURCE_ID, [
             "label" => "new-name",
         ]);
-        $this->assertInstanceOf("Stripe\\Terminal\\Reader", $resource);
+        $this->assertInstanceOf(\Stripe\Terminal\Reader::class, $resource);
     }
 
     public function testIsCreatable()
@@ -61,7 +61,7 @@ public function testIsCreatable()
             ["registration_code" => "a-b-c"]
         );
         $resource = Reader::create(['registration_code' => 'a-b-c']);
-        $this->assertInstanceOf("Stripe\\Terminal\\Reader", $resource);
+        $this->assertInstanceOf(\Stripe\Terminal\Reader::class, $resource);
     }
 
     public function testIsDeletable()
@@ -72,6 +72,6 @@ public function testIsDeletable()
             '/v1/terminal/readers/' . self::TEST_RESOURCE_ID
         );
         $resource->delete();
-        $this->assertInstanceOf("Stripe\\Terminal\\Reader", $resource);
+        $this->assertInstanceOf(\Stripe\Terminal\Reader::class, $resource);
     }
 }
diff --git a/tests/Stripe/ThreeDSecureTest.php b/tests/Stripe/ThreeDSecureTest.php
index f56e649cb..4e304fb7b 100644
--- a/tests/Stripe/ThreeDSecureTest.php
+++ b/tests/Stripe/ThreeDSecureTest.php
@@ -13,7 +13,7 @@ public function testIsRetrievable()
             '/v1/3d_secure/' . self::TEST_RESOURCE_ID
         );
         $resource = ThreeDSecure::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\ThreeDSecure", $resource);
+        $this->assertInstanceOf(\Stripe\ThreeDSecure::class, $resource);
     }
 
     public function testIsCreatable()
@@ -27,6 +27,6 @@ public function testIsCreatable()
             "currency" => "usd",
             "return_url" => "url"
         ]);
-        $this->assertInstanceOf("Stripe\\ThreeDSecure", $resource);
+        $this->assertInstanceOf(\Stripe\ThreeDSecure::class, $resource);
     }
 }
diff --git a/tests/Stripe/TokenTest.php b/tests/Stripe/TokenTest.php
index 36bb4bc82..7b1b781f6 100644
--- a/tests/Stripe/TokenTest.php
+++ b/tests/Stripe/TokenTest.php
@@ -13,7 +13,7 @@ public function testIsRetrievable()
             '/v1/tokens/' . self::TEST_RESOURCE_ID
         );
         $resource = Token::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\Token", $resource);
+        $this->assertInstanceOf(\Stripe\Token::class, $resource);
     }
 
     public function testIsCreatable()
@@ -23,6 +23,6 @@ public function testIsCreatable()
             '/v1/tokens'
         );
         $resource = Token::create(["card" => "tok_visa"]);
-        $this->assertInstanceOf("Stripe\\Token", $resource);
+        $this->assertInstanceOf(\Stripe\Token::class, $resource);
     }
 }
diff --git a/tests/Stripe/TopupTest.php b/tests/Stripe/TopupTest.php
index 9990b30ed..fe4001847 100644
--- a/tests/Stripe/TopupTest.php
+++ b/tests/Stripe/TopupTest.php
@@ -14,7 +14,7 @@ public function testIsListable()
         );
         $resources = Topup::all();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\Topup", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\Topup::class, $resources->data[0]);
     }
 
     public function testIsRetrievable()
@@ -24,7 +24,7 @@ public function testIsRetrievable()
             '/v1/topups/' . self::TEST_RESOURCE_ID
         );
         $resource = Topup::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\Topup", $resource);
+        $this->assertInstanceOf(\Stripe\Topup::class, $resource);
     }
 
     public function testIsCreatable()
@@ -40,7 +40,7 @@ public function testIsCreatable()
             "description" => "description",
             "statement_descriptor" => "statement descriptor"
         ]);
-        $this->assertInstanceOf("Stripe\\Topup", $resource);
+        $this->assertInstanceOf(\Stripe\Topup::class, $resource);
     }
 
     public function testIsSaveable()
@@ -52,7 +52,7 @@ public function testIsSaveable()
             '/v1/topups/' . $resource->id
         );
         $resource->save();
-        $this->assertInstanceOf("Stripe\\Topup", $resource);
+        $this->assertInstanceOf(\Stripe\Topup::class, $resource);
     }
 
     public function testIsUpdatable()
@@ -64,7 +64,7 @@ public function testIsUpdatable()
         $resource = Topup::update(self::TEST_RESOURCE_ID, [
             "metadata" => ["key" => "value"],
         ]);
-        $this->assertInstanceOf("Stripe\\Topup", $resource);
+        $this->assertInstanceOf(\Stripe\Topup::class, $resource);
     }
 
     public function testIsCancelable()
@@ -75,6 +75,6 @@ public function testIsCancelable()
             '/v1/topups/' . self::TEST_RESOURCE_ID . '/cancel'
         );
         $resource = $resource->cancel();
-        $this->assertInstanceOf("Stripe\\Topup", $resource);
+        $this->assertInstanceOf(\Stripe\Topup::class, $resource);
     }
 }
diff --git a/tests/Stripe/TransferReversalTest.php b/tests/Stripe/TransferReversalTest.php
index 37101c732..21e9986ef 100644
--- a/tests/Stripe/TransferReversalTest.php
+++ b/tests/Stripe/TransferReversalTest.php
@@ -16,6 +16,6 @@ public function testIsSaveable()
             '/v1/transfers/' . $resource->transfer . '/reversals/' . $resource->id
         );
         $resource->save();
-        $this->assertInstanceOf("Stripe\\TransferReversal", $resource);
+        $this->assertInstanceOf(\Stripe\TransferReversal::class, $resource);
     }
 }
diff --git a/tests/Stripe/TransferTest.php b/tests/Stripe/TransferTest.php
index d60d560e7..e561ba701 100644
--- a/tests/Stripe/TransferTest.php
+++ b/tests/Stripe/TransferTest.php
@@ -15,7 +15,7 @@ public function testIsListable()
         );
         $resources = Transfer::all();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\Transfer", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\Transfer::class, $resources->data[0]);
     }
 
     public function testIsRetrievable()
@@ -25,7 +25,7 @@ public function testIsRetrievable()
             '/v1/transfers/' . self::TEST_RESOURCE_ID
         );
         $resource = Transfer::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\Transfer", $resource);
+        $this->assertInstanceOf(\Stripe\Transfer::class, $resource);
     }
 
     public function testIsCreatable()
@@ -39,7 +39,7 @@ public function testIsCreatable()
             "currency" => "usd",
             "destination" => "acct_123"
         ]);
-        $this->assertInstanceOf("Stripe\\Transfer", $resource);
+        $this->assertInstanceOf(\Stripe\Transfer::class, $resource);
     }
 
     public function testIsSaveable()
@@ -51,7 +51,7 @@ public function testIsSaveable()
             '/v1/transfers/' . $resource->id
         );
         $resource->save();
-        $this->assertInstanceOf("Stripe\\Transfer", $resource);
+        $this->assertInstanceOf(\Stripe\Transfer::class, $resource);
     }
 
     public function testIsUpdatable()
@@ -63,7 +63,7 @@ public function testIsUpdatable()
         $resource = Transfer::update(self::TEST_RESOURCE_ID, [
             "metadata" => ["key" => "value"],
         ]);
-        $this->assertInstanceOf("Stripe\\Transfer", $resource);
+        $this->assertInstanceOf(\Stripe\Transfer::class, $resource);
     }
 
     public function testIsReversable()
@@ -74,7 +74,7 @@ public function testIsReversable()
             '/v1/transfers/' . $resource->id . '/reversals'
         );
         $resource->reverse();
-        $this->assertInstanceOf("Stripe\\Transfer", $resource);
+        $this->assertInstanceOf(\Stripe\Transfer::class, $resource);
     }
 
     public function testIsCancelable()
@@ -87,7 +87,7 @@ public function testIsCancelable()
             '/v1/transfers/' . $transfer->id . '/cancel'
         );
         $resource = $transfer->cancel();
-        $this->assertInstanceOf("Stripe\\Transfer", $resource);
+        $this->assertInstanceOf(\Stripe\Transfer::class, $resource);
         $this->assertSame($resource, $transfer);
     }
 
@@ -98,7 +98,7 @@ public function testCanCreateReversal()
             '/v1/transfers/' . self::TEST_RESOURCE_ID . '/reversals'
         );
         $resource = Transfer::createReversal(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\TransferReversal", $resource);
+        $this->assertInstanceOf(\Stripe\TransferReversal::class, $resource);
     }
 
     public function testCanRetrieveReversal()
@@ -108,7 +108,7 @@ public function testCanRetrieveReversal()
             '/v1/transfers/' . self::TEST_RESOURCE_ID . '/reversals/' . self::TEST_REVERSAL_ID
         );
         $resource = Transfer::retrieveReversal(self::TEST_RESOURCE_ID, self::TEST_REVERSAL_ID);
-        $this->assertInstanceOf("Stripe\\TransferReversal", $resource);
+        $this->assertInstanceOf(\Stripe\TransferReversal::class, $resource);
     }
 
     public function testCanUpdateReversal()
@@ -124,7 +124,7 @@ public function testCanUpdateReversal()
                 "metadata" => ["key" => "value"],
             ]
         );
-        $this->assertInstanceOf("Stripe\\TransferReversal", $resource);
+        $this->assertInstanceOf(\Stripe\TransferReversal::class, $resource);
     }
 
     public function testCanListReversal()
@@ -135,6 +135,6 @@ public function testCanListReversal()
         );
         $resources = Transfer::allReversals(self::TEST_RESOURCE_ID);
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\TransferReversal", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\TransferReversal::class, $resources->data[0]);
     }
 }
diff --git a/tests/Stripe/UsageRecordTest.php b/tests/Stripe/UsageRecordTest.php
index c5fe37306..efff6d884 100644
--- a/tests/Stripe/UsageRecordTest.php
+++ b/tests/Stripe/UsageRecordTest.php
@@ -18,7 +18,7 @@ public function testIsCreatable()
             'timestamp' => 12341234,
             'action' => 'set'
         ]);
-        $this->assertInstanceOf("Stripe\\UsageRecord", $resource);
+        $this->assertInstanceOf(\Stripe\UsageRecord::class, $resource);
     }
 
     /**
diff --git a/tests/Stripe/WebhookEndpointTest.php b/tests/Stripe/WebhookEndpointTest.php
index e01828ad4..bba535201 100644
--- a/tests/Stripe/WebhookEndpointTest.php
+++ b/tests/Stripe/WebhookEndpointTest.php
@@ -14,7 +14,7 @@ public function testIsListable()
         );
         $resources = WebhookEndpoint::all();
         $this->assertTrue(is_array($resources->data));
-        $this->assertInstanceOf("Stripe\\WebhookEndpoint", $resources->data[0]);
+        $this->assertInstanceOf(\Stripe\WebhookEndpoint::class, $resources->data[0]);
     }
 
     public function testIsRetrievable()
@@ -24,7 +24,7 @@ public function testIsRetrievable()
             '/v1/webhook_endpoints/' . self::TEST_RESOURCE_ID
         );
         $resource = WebhookEndpoint::retrieve(self::TEST_RESOURCE_ID);
-        $this->assertInstanceOf("Stripe\\WebhookEndpoint", $resource);
+        $this->assertInstanceOf(\Stripe\WebhookEndpoint::class, $resource);
     }
 
     public function testIsCreatable()
@@ -37,7 +37,7 @@ public function testIsCreatable()
             'enabled_events' => ['charge.succeeded'],
             'url' => 'https://stripe.com',
         ]);
-        $this->assertInstanceOf("Stripe\\WebhookEndpoint", $resource);
+        $this->assertInstanceOf(\Stripe\WebhookEndpoint::class, $resource);
     }
 
     public function testIsSaveable()
@@ -49,7 +49,7 @@ public function testIsSaveable()
             '/v1/webhook_endpoints/' . self::TEST_RESOURCE_ID
         );
         $resource->save();
-        $this->assertInstanceOf("Stripe\\WebhookEndpoint", $resource);
+        $this->assertInstanceOf(\Stripe\WebhookEndpoint::class, $resource);
     }
 
     public function testIsUpdatable()
@@ -61,7 +61,7 @@ public function testIsUpdatable()
         $resource = WebhookEndpoint::update(self::TEST_RESOURCE_ID, [
             'enabled_events' => ['charge.succeeded'],
         ]);
-        $this->assertInstanceOf("Stripe\\WebhookEndpoint", $resource);
+        $this->assertInstanceOf(\Stripe\WebhookEndpoint::class, $resource);
     }
 
     public function testIsDeletable()
@@ -72,6 +72,6 @@ public function testIsDeletable()
             '/v1/webhook_endpoints/' . self::TEST_RESOURCE_ID
         );
         $resource->delete();
-        $this->assertInstanceOf("Stripe\\WebhookEndpoint", $resource);
+        $this->assertInstanceOf(\Stripe\WebhookEndpoint::class, $resource);
     }
 }