diff --git a/src/Z38/SwissPayment/AccountInterface.php b/src/Z38/SwissPayment/AccountInterface.php
index fed6e06..c533010 100644
--- a/src/Z38/SwissPayment/AccountInterface.php
+++ b/src/Z38/SwissPayment/AccountInterface.php
@@ -18,7 +18,7 @@ interface AccountInterface
     public function format();
 
     /**
-     * Returns a XML representation to identify the account
+     * Returns an XML representation to identify the account
      *
      * @param DOMDocument $doc
      *
diff --git a/src/Z38/SwissPayment/BIC.php b/src/Z38/SwissPayment/BIC.php
index 1f2f90d..5bb416e 100644
--- a/src/Z38/SwissPayment/BIC.php
+++ b/src/Z38/SwissPayment/BIC.php
@@ -2,12 +2,15 @@
 
 namespace Z38\SwissPayment;
 
+use DOMDocument;
+use InvalidArgumentException;
+
 /**
  * BIC
  */
 class BIC implements FinancialInstitutionInterface
 {
-    const PATTERN = '/^[A-Z]{6,6}[A-Z2-9][A-NP-Z0-9]([A-Z0-9]{3,3}){0,1}$/';
+    private const PATTERN = '/^[A-Z]{6,6}[A-Z2-9][A-NP-Z0-9]([A-Z0-9]{3,3}){0,1}$/';
 
     /**
      * @var string
@@ -19,12 +22,12 @@ class BIC implements FinancialInstitutionInterface
      *
      * @param string $bic
      *
-     * @throws \InvalidArgumentException When the BIC does contain invalid characters or the length does not match.
+     * @throws InvalidArgumentException When the BIC does contain invalid characters or the length does not match.
      */
     public function __construct($bic)
     {
         if (!preg_match(self::PATTERN, $bic)) {
-            throw new \InvalidArgumentException('BIC is not properly formatted.');
+            throw new InvalidArgumentException('BIC is not properly formatted.');
         }
 
         $this->bic = $bic;
@@ -43,7 +46,7 @@ public function format()
     /**
      * {@inheritdoc}
      */
-    public function asDom(\DOMDocument $doc)
+    public function asDom(DOMDocument $doc)
     {
         $xml = $doc->createElement('FinInstnId');
         $xml->appendChild($doc->createElement('BIC', $this->format()));
diff --git a/src/Z38/SwissPayment/FinancialInstitutionAddress.php b/src/Z38/SwissPayment/FinancialInstitutionAddress.php
index 364bcbd..25f386c 100644
--- a/src/Z38/SwissPayment/FinancialInstitutionAddress.php
+++ b/src/Z38/SwissPayment/FinancialInstitutionAddress.php
@@ -2,6 +2,9 @@
 
 namespace Z38\SwissPayment;
 
+use DOMDocument;
+use InvalidArgumentException;
+
 /**
  * FinancialInstitutionAddress holds information to identify a FI by name and address
  */
@@ -23,7 +26,7 @@ class FinancialInstitutionAddress implements FinancialInstitutionInterface
      * @param string                 $name    Name of the FI
      * @param PostalAddressInterface $address Address of the FI
      *
-     * @throws \InvalidArgumentException When the name is invalid.
+     * @throws InvalidArgumentException When the name is invalid.
      */
     public function __construct($name, PostalAddressInterface $address)
     {
@@ -34,7 +37,7 @@ public function __construct($name, PostalAddressInterface $address)
     /**
      * {@inheritdoc}
      */
-    public function asDom(\DOMDocument $doc)
+    public function asDom(DOMDocument $doc)
     {
         $xml = $doc->createElement('FinInstnId');
         $xml->appendChild(Text::xml($doc, 'Nm', $this->name));
diff --git a/src/Z38/SwissPayment/FinancialInstitutionInterface.php b/src/Z38/SwissPayment/FinancialInstitutionInterface.php
index 2d9c39f..bc683e1 100644
--- a/src/Z38/SwissPayment/FinancialInstitutionInterface.php
+++ b/src/Z38/SwissPayment/FinancialInstitutionInterface.php
@@ -2,17 +2,20 @@
 
 namespace Z38\SwissPayment;
 
+use DOMDocument;
+use DOMElement;
+
 /**
  * General interface for financial institutions
  */
 interface FinancialInstitutionInterface
 {
     /**
-     * Returns a XML representation to identify the financial institution
+     * Returns an XML representation to identify the financial institution
      *
-     * @param \DOMDocument $doc
+     * @param DOMDocument $doc
      *
-     * @return \DOMElement The built DOM element
+     * @return DOMElement The built DOM element
      */
-    public function asDom(\DOMDocument $doc);
+    public function asDom(DOMDocument $doc);
 }
diff --git a/src/Z38/SwissPayment/IBAN.php b/src/Z38/SwissPayment/IBAN.php
index 5f930d5..e1e37a5 100644
--- a/src/Z38/SwissPayment/IBAN.php
+++ b/src/Z38/SwissPayment/IBAN.php
@@ -3,14 +3,14 @@
 namespace Z38\SwissPayment;
 
 use DOMDocument;
+use InvalidArgumentException;
 
 /**
  * IBAN
  */
 class IBAN implements AccountInterface
 {
-    const MAX_LENGTH = 34;
-    const PATTERN = '/^[A-Z]{2,2}[0-9]{2,2}[A-Z0-9]{1,30}$/';
+    private const PATTERN = '/^[A-Z]{2,2}[0-9]{2,2}[A-Z0-9]{1,30}$/';
 
     /**
      * @var string
@@ -22,16 +22,16 @@ class IBAN implements AccountInterface
      *
      * @param string $iban
      *
-     * @throws \InvalidArgumentException When the IBAN does contain invalid characters or the checksum calculation fails.
+     * @throws InvalidArgumentException When the IBAN does contain invalid characters or the checksum calculation fails.
      */
     public function __construct($iban)
     {
         $cleanedIban = str_replace(' ', '', strtoupper($iban));
         if (!preg_match(self::PATTERN, $cleanedIban)) {
-            throw new \InvalidArgumentException('IBAN is not properly formatted.');
+            throw new InvalidArgumentException('IBAN is not properly formatted.');
         }
         if (!self::check($cleanedIban)) {
-            throw new \InvalidArgumentException('IBAN has an invalid checksum.');
+            throw new InvalidArgumentException('IBAN has an invalid checksum.');
         }
 
         $this->iban = $cleanedIban;
diff --git a/src/Z38/SwissPayment/IID.php b/src/Z38/SwissPayment/IID.php
index 0b82d63..5a4ea9f 100644
--- a/src/Z38/SwissPayment/IID.php
+++ b/src/Z38/SwissPayment/IID.php
@@ -20,7 +20,7 @@ class IID implements FinancialInstitutionInterface
      *
      * @param string $iid
      *
-     * @throws \InvalidArgumentException When the IID does contain invalid characters or the length does not match.
+     * @throws InvalidArgumentException When the IID does contain invalid characters or the length does not match.
      */
     public function __construct($iid)
     {
@@ -37,7 +37,7 @@ public function __construct($iid)
      *
      * @param IBAN $iban
      *
-     * @throws \InvalidArgumentException When the supplied IBAN is not from a supported country.
+     * @return IID
      */
     public static function fromIBAN(IBAN $iban)
     {
diff --git a/src/Z38/SwissPayment/ISRParticipant.php b/src/Z38/SwissPayment/ISRParticipant.php
index be68f6f..7d88c51 100644
--- a/src/Z38/SwissPayment/ISRParticipant.php
+++ b/src/Z38/SwissPayment/ISRParticipant.php
@@ -20,7 +20,7 @@ class ISRParticipant implements AccountInterface
      *
      * @param string $number
      *
-     * @throws \InvalidArgumentException When the participation number is not valid.
+     * @throws InvalidArgumentException When the participation number is not valid.
      */
     public function __construct($number)
     {
diff --git a/src/Z38/SwissPayment/Message/AbstractMessage.php b/src/Z38/SwissPayment/Message/AbstractMessage.php
index 92f88b5..2f73744 100644
--- a/src/Z38/SwissPayment/Message/AbstractMessage.php
+++ b/src/Z38/SwissPayment/Message/AbstractMessage.php
@@ -2,6 +2,8 @@
 
 namespace Z38\SwissPayment\Message;
 
+use DOMDocument;
+use DOMElement;
 use Z38\SwissPayment\Text;
 
 /**
@@ -12,11 +14,11 @@ abstract class AbstractMessage implements MessageInterface
     /**
      * Builds the DOM of the actual message
      *
-     * @param \DOMDocument $doc
+     * @param DOMDocument $doc
      *
-     * @return \DOMElement
+     * @return DOMElement
      */
-    abstract protected function buildDom(\DOMDocument $doc);
+    abstract protected function buildDom(DOMDocument $doc);
 
     /**
      * Gets the name of the schema
@@ -35,14 +37,14 @@ abstract protected function getSchemaLocation();
     /**
      * Builds a DOM document of the message
      *
-     * @return \DOMDocument
+     * @return DOMDocument
      */
     public function asDom()
     {
         $schema = $this->getSchemaName();
         $location = $this->getSchemaLocation();
 
-        $doc = new \DOMDocument('1.0', 'UTF-8');
+        $doc = new DOMDocument('1.0', 'UTF-8');
         $root = $doc->createElement('Document');
         $root->setAttribute('xmlns', $schema);
         if ($location !== null) {
@@ -86,11 +88,11 @@ public function getSoftwareVersion()
     /**
      * Creates a DOM element which contains details about the software used to create the message
      *
-     * @param \DOMDocument $doc
+     * @param DOMDocument $doc
      *
-     * @return \DOMElement
+     * @return DOMElement
      */
-    protected function buildContactDetails(\DOMDocument $doc)
+    protected function buildContactDetails(DOMDocument $doc)
     {
         $root = $doc->createElement('CtctDtls');
 
diff --git a/src/Z38/SwissPayment/Message/CustomerCreditTransfer.php b/src/Z38/SwissPayment/Message/CustomerCreditTransfer.php
index 9292e41..d96492f 100644
--- a/src/Z38/SwissPayment/Message/CustomerCreditTransfer.php
+++ b/src/Z38/SwissPayment/Message/CustomerCreditTransfer.php
@@ -2,6 +2,9 @@
 
 namespace Z38\SwissPayment\Message;
 
+use DateTime;
+use DOMDocument;
+use InvalidArgumentException;
 use Z38\SwissPayment\Money;
 use Z38\SwissPayment\PaymentInformation\PaymentInformation;
 use Z38\SwissPayment\Text;
@@ -27,7 +30,7 @@ class CustomerCreditTransfer extends AbstractMessage
     protected $payments;
 
     /**
-     * @var \DateTime
+     * @var DateTime
      */
     protected $creationTime;
 
@@ -37,24 +40,24 @@ class CustomerCreditTransfer extends AbstractMessage
      * @param string $id              Identifier of the message (should usually be unique over a period of at least 90 days)
      * @param string $initiatingParty Name of the initiating party
      *
-     * @throws \InvalidArgumentException When any of the inputs contain invalid characters or are too long.
+     * @throws InvalidArgumentException When any of the inputs contain invalid characters or are too long.
      */
     public function __construct($id, $initiatingParty)
     {
         $this->id = Text::assertIdentifier($id);
         $this->initiatingParty = Text::assert($initiatingParty, 70);
         $this->payments = [];
-        $this->creationTime = new \DateTime();
+        $this->creationTime = new DateTime();
     }
 
     /**
      * Manually sets the creation time
      *
-     * @param \DateTime $creationTime The desired creation time
+     * @param DateTime $creationTime The desired creation time
      *
      * @return CustomerCreditTransfer This message
      */
-    public function setCreationTime(\DateTime $creationTime)
+    public function setCreationTime(DateTime $creationTime)
     {
         $this->creationTime = $creationTime;
 
@@ -104,7 +107,7 @@ protected function getSchemaLocation()
     /**
      * {@inheritdoc}
      */
-    protected function buildDom(\DOMDocument $doc)
+    protected function buildDom(DOMDocument $doc)
     {
         $transactionCount = 0;
         $transactionSum = new Money\MixedMoney(0);
diff --git a/src/Z38/SwissPayment/Message/MessageInterface.php b/src/Z38/SwissPayment/Message/MessageInterface.php
index 1cdfad1..5bcbe56 100644
--- a/src/Z38/SwissPayment/Message/MessageInterface.php
+++ b/src/Z38/SwissPayment/Message/MessageInterface.php
@@ -8,7 +8,7 @@
 interface MessageInterface
 {
     /**
-     * Returns a XML representation of the message
+     * Returns an XML representation of the message
      *
      * @return string The XML source
      */
diff --git a/src/Z38/SwissPayment/Money/MixedMoney.php b/src/Z38/SwissPayment/Money/MixedMoney.php
index a63548a..f7cac7a 100644
--- a/src/Z38/SwissPayment/Money/MixedMoney.php
+++ b/src/Z38/SwissPayment/Money/MixedMoney.php
@@ -41,7 +41,7 @@ final protected function getDecimals()
     }
 
     /**
-     * Returns the sum of this and an other amount of money
+     * Returns the sum of this and another amount of money
      *
      * @param Money $addend The addend
      *
@@ -55,7 +55,7 @@ public function plus(Money $addend)
     }
 
     /**
-     * Returns the subtraction of this and an other amount of money
+     * Returns the subtraction of this and another amount of money
      *
      * @param Money $subtrahend The subtrahend
      *
diff --git a/src/Z38/SwissPayment/Money/Money.php b/src/Z38/SwissPayment/Money/Money.php
index 1cf5da3..7c9897e 100644
--- a/src/Z38/SwissPayment/Money/Money.php
+++ b/src/Z38/SwissPayment/Money/Money.php
@@ -2,6 +2,8 @@
 
 namespace Z38\SwissPayment\Money;
 
+use InvalidArgumentException;
+
 /**
  * Base class for all currencies
  */
@@ -66,54 +68,54 @@ public function getAmount()
     }
 
     /**
-     * Returns the sum of this and an other amount of money
+     * Returns the sum of this and another amount of money
      *
      * @param Money $addend The addend
      *
      * @return Money The sum
      *
-     * @throws \InvalidArgumentException When the currencies do not match
+     * @throws InvalidArgumentException When the currencies do not match
      */
     public function plus(self $addend)
     {
         if ($this->getCurrency() !== $addend->getCurrency()) {
-            throw new \InvalidArgumentException('Can not add different currencies');
+            throw new InvalidArgumentException('Can not add different currencies');
         }
 
         return new static($this->cents + $addend->getAmount());
     }
 
     /**
-     * Returns the subtraction of this and an other amount of money
+     * Returns the subtraction of this and another amount of money
      *
      * @param Money $subtrahend The subtrahend
      *
      * @return Money The difference
      *
-     * @throws \InvalidArgumentException When the currencies do not match
+     * @throws InvalidArgumentException When the currencies do not match
      */
     public function minus(self $subtrahend)
     {
         if ($this->getCurrency() !== $subtrahend->getCurrency()) {
-            throw new \InvalidArgumentException('Can not subtract different currencies');
+            throw new InvalidArgumentException('Can not subtract different currencies');
         }
 
         return new static($this->cents - $subtrahend->getAmount());
     }
 
     /**
-     * Compares this instance with an other instance.
+     * Compares this instance with another instance.
      *
      * @param Money $b The instance to which this instance is to be compared.
      *
      * @return int -1, 0 or 1 as this instance is less than, equal to, or greater than $b
      *
-     * @throws \InvalidArgumentException When the currencies do not match
+     * @throws InvalidArgumentException When the currencies do not match
      */
     public function compareTo(self $b)
     {
         if ($this->getCurrency() !== $b->getCurrency()) {
-            throw new \InvalidArgumentException('Can not compare different currencies');
+            throw new InvalidArgumentException('Can not compare different currencies');
         }
 
         if ($this->getAmount() < $b->getAmount()) {
diff --git a/src/Z38/SwissPayment/PaymentInformation/CategoryPurposeCode.php b/src/Z38/SwissPayment/PaymentInformation/CategoryPurposeCode.php
index eb27b44..013b284 100644
--- a/src/Z38/SwissPayment/PaymentInformation/CategoryPurposeCode.php
+++ b/src/Z38/SwissPayment/PaymentInformation/CategoryPurposeCode.php
@@ -3,6 +3,7 @@
 namespace Z38\SwissPayment\PaymentInformation;
 
 use DOMDocument;
+use DOMElement;
 use InvalidArgumentException;
 
 /**
@@ -33,11 +34,11 @@ public function __construct($code)
     }
 
     /**
-     * Returns a XML representation of this purpose
+     * Returns an XML representation of this purpose
      *
-     * @param \DOMDocument $doc
+     * @param DOMDocument $doc
      *
-     * @return \DOMElement The built DOM element
+     * @return DOMElement The built DOM element
      */
     public function asDom(DOMDocument $doc)
     {
diff --git a/src/Z38/SwissPayment/PaymentInformation/PaymentInformation.php b/src/Z38/SwissPayment/PaymentInformation/PaymentInformation.php
index 5c334c4..129e3c8 100644
--- a/src/Z38/SwissPayment/PaymentInformation/PaymentInformation.php
+++ b/src/Z38/SwissPayment/PaymentInformation/PaymentInformation.php
@@ -2,6 +2,11 @@
 
 namespace Z38\SwissPayment\PaymentInformation;
 
+use DateTime;
+use DOMDocument;
+use DOMElement;
+use InvalidArgumentException;
+use LogicException;
 use Z38\SwissPayment\BIC;
 use Z38\SwissPayment\FinancialInstitutionInterface;
 use Z38\SwissPayment\IBAN;
@@ -46,7 +51,7 @@ class PaymentInformation
     protected $categoryPurpose;
 
     /**
-     * @var \DateTime
+     * @var DateTime
      */
     protected $executionDate;
 
@@ -73,18 +78,18 @@ class PaymentInformation
      * @param BIC|IID $debtorAgent BIC or IID of the debtor's financial institution
      * @param IBAN    $debtorIBAN  IBAN of the debtor's account
      *
-     * @throws \InvalidArgumentException When any of the inputs contain invalid characters or are too long.
+     * @throws InvalidArgumentException When any of the inputs contain invalid characters or are too long.
      */
     public function __construct($id, $debtorName, FinancialInstitutionInterface $debtorAgent, IBAN $debtorIBAN)
     {
         if (!$debtorAgent instanceof BIC && !$debtorAgent instanceof IID) {
-            throw new \InvalidArgumentException('The debtor agent must be an instance of BIC or IID.');
+            throw new InvalidArgumentException('The debtor agent must be an instance of BIC or IID.');
         }
 
         $this->id = Text::assertIdentifier($id);
         $this->transactions = [];
         $this->batchBooking = true;
-        $this->executionDate = new \DateTime();
+        $this->executionDate = new DateTime();
         $this->debtorName = Text::assert($debtorName, 70);
         $this->debtorAgent = $debtorAgent;
         $this->debtorIBAN = $debtorIBAN;
@@ -134,11 +139,11 @@ public function getTransactionSum()
      * Sets the required execution date.
      * Where appropriate, the value data is automatically modified to the next possible banking/Post Office working day.
      *
-     * @param \DateTime $executionDate
+     * @param DateTime $executionDate
      *
      * @return PaymentInformation This payment instruction
      */
-    public function setExecutionDate(\DateTime $executionDate)
+    public function setExecutionDate(DateTime $executionDate)
     {
         $this->executionDate = $executionDate;
 
@@ -207,11 +212,11 @@ public function setCategoryPurpose(CategoryPurposeCode $categoryPurpose)
     /**
      * Builds a DOM tree of this payment instruction
      *
-     * @param \DOMDocument $doc
+     * @param DOMDocument $doc
      *
-     * @return \DOMElement The built DOM tree
+     * @return DOMElement The built DOM tree
      */
-    public function asDom(\DOMDocument $doc)
+    public function asDom(DOMDocument $doc)
     {
         $root = $doc->createElement('PmtInf');
 
@@ -219,6 +224,9 @@ public function asDom(\DOMDocument $doc)
         $root->appendChild($doc->createElement('PmtMtd', 'TRF'));
         $root->appendChild($doc->createElement('BtchBookg', ($this->batchBooking ? 'true' : 'false')));
 
+        $localInstrument = null;
+        $serviceLevel = null;
+
         if ($this->hasPaymentTypeInformation()) {
             $paymentType = $doc->createElement('PmtTpInf');
             $localInstrument = $this->localInstrument ?: $this->inferLocalInstrument();
@@ -260,10 +268,10 @@ public function asDom(\DOMDocument $doc)
         foreach ($this->transactions as $transaction) {
             if ($this->hasPaymentTypeInformation()) {
                 if ($transaction->getLocalInstrument() !== $localInstrument) {
-                    throw new \LogicException('You can not set the local instrument on B- and C-level.');
+                    throw new LogicException('You can not set the local instrument on B- and C-level.');
                 }
                 if ($transaction->getServiceLevel() !== $serviceLevel) {
-                    throw new \LogicException('You can not set the service level on B- and C-level.');
+                    throw new LogicException('You can not set the service level on B- and C-level.');
                 }
             }
             $root->appendChild($transaction->asDom($doc, $this));
@@ -272,6 +280,9 @@ public function asDom(\DOMDocument $doc)
         return $root;
     }
 
+    /**
+     * @return string|null
+     */
     private function inferServiceLevel()
     {
         if (!count($this->transactions)) {
@@ -281,6 +292,9 @@ private function inferServiceLevel()
         return $this->transactions[0]->getServiceLevel();
     }
 
+    /**
+     * @return string|null
+     */
     private function inferLocalInstrument()
     {
         if (!count($this->transactions)) {
diff --git a/src/Z38/SwissPayment/PostalAccount.php b/src/Z38/SwissPayment/PostalAccount.php
index 21e90db..2f65337 100644
--- a/src/Z38/SwissPayment/PostalAccount.php
+++ b/src/Z38/SwissPayment/PostalAccount.php
@@ -10,7 +10,7 @@
  */
 class PostalAccount implements AccountInterface
 {
-    const PATTERN = '/^[0-9]{2}-[1-9][0-9]{0,5}-[0-9]$/';
+    private const PATTERN = '/^[0-9]{2}-[1-9][0-9]{0,5}-[0-9]$/';
 
     /**
      * @var int
@@ -74,7 +74,8 @@ public function asDom(DOMDocument $doc)
     }
 
     /**
-     * @internal
+     * @param $number
+     * @return bool
      */
     public static function validateCheckDigit($number)
     {
diff --git a/src/Z38/SwissPayment/PostalAddressInterface.php b/src/Z38/SwissPayment/PostalAddressInterface.php
index 749883f..cc57235 100644
--- a/src/Z38/SwissPayment/PostalAddressInterface.php
+++ b/src/Z38/SwissPayment/PostalAddressInterface.php
@@ -2,17 +2,20 @@
 
 namespace Z38\SwissPayment;
 
+use DOMDocument;
+use DOMElement;
+
 /**
  * PostalAddressInterface
  */
 interface PostalAddressInterface
 {
     /**
-     * Returns a XML representation of the address
+     * Returns an XML representation of the address
      *
-     * @param \DOMDocument $doc
+     * @param DOMDocument $doc
      *
-     * @return \DOMElement The built DOM element
+     * @return DOMElement The built DOM element
      */
-    public function asDom(\DOMDocument $doc);
+    public function asDom(DOMDocument $doc);
 }
diff --git a/src/Z38/SwissPayment/StructuredPostalAddress.php b/src/Z38/SwissPayment/StructuredPostalAddress.php
index 7de3efa..1598cb4 100644
--- a/src/Z38/SwissPayment/StructuredPostalAddress.php
+++ b/src/Z38/SwissPayment/StructuredPostalAddress.php
@@ -2,6 +2,9 @@
 
 namespace Z38\SwissPayment;
 
+use DOMDocument;
+use InvalidArgumentException;
+
 /**
  * This class holds a structured representation of a postal address
  */
@@ -41,7 +44,7 @@ class StructuredPostalAddress implements PostalAddressInterface
      * @param string      $town       Town name
      * @param string      $country    Country code (ISO 3166-1 alpha-2)
      *
-     * @throws \InvalidArgumentException When the address contains invalid characters or is too long.
+     * @throws InvalidArgumentException When the address contains invalid characters or is too long.
      */
     public function __construct($street, $buildingNo, $postCode, $town, $country = 'CH')
     {
@@ -77,7 +80,7 @@ public static function sanitize($street, $buildingNo, $postCode, $town, $country
     /**
      * {@inheritdoc}
      */
-    public function asDom(\DOMDocument $doc)
+    public function asDom(DOMDocument $doc)
     {
         $root = $doc->createElement('PstlAdr');
 
diff --git a/src/Z38/SwissPayment/Text.php b/src/Z38/SwissPayment/Text.php
index 0e51b77..76a93a5 100644
--- a/src/Z38/SwissPayment/Text.php
+++ b/src/Z38/SwissPayment/Text.php
@@ -3,12 +3,17 @@
 namespace Z38\SwissPayment;
 
 use DOMDocument;
+use DOMElement;
+use DOMException;
 use InvalidArgumentException;
 
+/**
+ * This class permits to sanitize all texts
+ */
 class Text
 {
-    const TEXT_NON_CH = '/[^A-Za-z0-9 .,:\'\/()?+\-!"#%&*;<>÷=@_$£[\]{}\` ́~àáâäçèéêëìíîïñòóôöùúûüýßÀÁÂÄÇÈÉÊËÌÍÎÏÒÓÔÖÙÚÛÜÑ]+/u';
-    const TEXT_NON_SWIFT = '/[^A-Za-z0-9 .,:\'\/()?+\-]+/';
+    private const TEXT_NON_CH = '/[^A-Za-z0-9 .,:\'\/()?+\-!"#%&*;<>÷=@_$£[\]{}\` ́~àáâäçèéêëìíîïñòóôöùúûüýßÀÁÂÄÇÈÉÊËÌÍÎÏÒÓÔÖÙÚÛÜÑ]+/u';
+    private const TEXT_NON_SWIFT = '/[^A-Za-z0-9 .,:\'\/()?+\-]+/';
 
     /**
      * Sanitizes and trims a string to conform to the Swiss character
@@ -44,7 +49,9 @@ public static function sanitizeOptional($input, $maxLength)
     }
 
     /**
-     * @internal
+     * @param $input
+     * @param $maxLength
+     * @return string|null
      */
     public static function assertOptional($input, $maxLength)
     {
@@ -56,7 +63,9 @@ public static function assertOptional($input, $maxLength)
     }
 
     /**
-     * @internal
+     * @param $input
+     * @param $maxLength
+     * @return string
      */
     public static function assert($input, $maxLength)
     {
@@ -64,7 +73,8 @@ public static function assert($input, $maxLength)
     }
 
     /**
-     * @internal
+     * @param $input
+     * @return string
      */
     public static function assertIdentifier($input)
     {
@@ -77,7 +87,8 @@ public static function assertIdentifier($input)
     }
 
     /**
-     * @internal
+     * @param $input
+     * @return mixed
      */
     public static function assertCountryCode($input)
     {
@@ -88,6 +99,12 @@ public static function assertCountryCode($input)
         return $input;
     }
 
+    /**
+     * @param $input
+     * @param $maxLength
+     * @param $pattern
+     * @return string
+     */
     protected static function assertNotPattern($input, $maxLength, $pattern)
     {
         $length = function_exists('mb_strlen') ? mb_strlen($input, 'UTF-8') : strlen($input);
@@ -102,7 +119,11 @@ protected static function assertNotPattern($input, $maxLength, $pattern)
     }
 
     /**
-     * @internal
+     * @param DOMDocument $doc
+     * @param $tag
+     * @param $content
+     * @return DOMElement|false
+     * @throws DOMException
      */
     public static function xml(DOMDocument $doc, $tag, $content)
     {
diff --git a/src/Z38/SwissPayment/TransactionInformation/BankCreditTransfer.php b/src/Z38/SwissPayment/TransactionInformation/BankCreditTransfer.php
index e899ec9..e009c1d 100644
--- a/src/Z38/SwissPayment/TransactionInformation/BankCreditTransfer.php
+++ b/src/Z38/SwissPayment/TransactionInformation/BankCreditTransfer.php
@@ -32,7 +32,7 @@ class BankCreditTransfer extends CreditTransfer
      * @param IBAN    $creditorIBAN  IBAN of the creditor
      * @param BIC|IID $creditorAgent BIC or IID of the creditor's financial institution
      *
-     * @throws \InvalidArgumentException When the amount is not in EUR or CHF or when the creditor agent is not BIC or IID.
+     * @throws InvalidArgumentException When the amount is not in EUR or CHF or when the creditor agent is not BIC or IID.
      */
     public function __construct($instructionId, $endToEndId, Money\Money $amount, $creditorName, $creditorAddress, IBAN $creditorIBAN, FinancialInstitutionInterface $creditorAgent)
     {
diff --git a/src/Z38/SwissPayment/TransactionInformation/BankCreditTransferWithCreditorReference.php b/src/Z38/SwissPayment/TransactionInformation/BankCreditTransferWithCreditorReference.php
index 747df9d..e2a1b89 100644
--- a/src/Z38/SwissPayment/TransactionInformation/BankCreditTransferWithCreditorReference.php
+++ b/src/Z38/SwissPayment/TransactionInformation/BankCreditTransferWithCreditorReference.php
@@ -8,7 +8,6 @@
 use Z38\SwissPayment\FinancialInstitutionInterface;
 use Z38\SwissPayment\IBAN;
 use Z38\SwissPayment\Money;
-use Z38\SwissPayment\PostalAccount;
 
 /**
  * BankCreditTransfer contains all the information about a type 3 transaction
diff --git a/src/Z38/SwissPayment/TransactionInformation/BankCreditTransferWithQRR.php b/src/Z38/SwissPayment/TransactionInformation/BankCreditTransferWithQRR.php
index 2fe3260..7d39f18 100644
--- a/src/Z38/SwissPayment/TransactionInformation/BankCreditTransferWithQRR.php
+++ b/src/Z38/SwissPayment/TransactionInformation/BankCreditTransferWithQRR.php
@@ -29,7 +29,9 @@ class BankCreditTransferWithQRR extends BankCreditTransfer
      * @param $creditorName
      * @param $creditorAddress
      * @param IBAN $creditorIBAN  IBAN of the creditor
-     * @param FinancialInstitutionInterface $creditorAgent BIC or IID of the creditor's financial institution
+     * @param FinancialInstitutionInterface $creditorAgent BIC or IID 
+	 *        of the creditor's financial institution
+	 *        You can build the IID from the IBAN number for QRR (Only CH+LI)
      * @param string $creditorReference QR reference number (QRR)
      */
     public function __construct(
@@ -47,7 +49,7 @@ public function __construct(
         }
         $this->creditorReference = $creditorReference;
 
-        if (!preg_match('/^CH[0-9]{2}3/', $creditorIBAN->normalize())) {
+        if (!preg_match('/^(CH|LI)[0-9]{2}3/', $creditorIBAN->normalize())) {
             throw new InvalidArgumentException('The IBAN must be a QR-IBAN');
         }
 
diff --git a/src/Z38/SwissPayment/TransactionInformation/CreditTransfer.php b/src/Z38/SwissPayment/TransactionInformation/CreditTransfer.php
index 303f26b..333a7d0 100644
--- a/src/Z38/SwissPayment/TransactionInformation/CreditTransfer.php
+++ b/src/Z38/SwissPayment/TransactionInformation/CreditTransfer.php
@@ -2,6 +2,10 @@
 
 namespace Z38\SwissPayment\TransactionInformation;
 
+use DOMDocument;
+use DOMElement;
+use DOMNode;
+use InvalidArgumentException;
 use Z38\SwissPayment\Money\Money;
 use Z38\SwissPayment\PaymentInformation\PaymentInformation;
 use Z38\SwissPayment\PostalAddressInterface;
@@ -66,7 +70,7 @@ abstract class CreditTransfer
      * @param string                      $creditorName    Name of the creditor
      * @param PostalAddressInterface|null $creditorAddress Address of the creditor
      *
-     * @throws \InvalidArgumentException When any of the inputs contain invalid characters or are too long.
+     * @throws InvalidArgumentException When any of the inputs contain invalid characters or are too long.
      */
     public function __construct($instructionId, $endToEndId, Money $amount, $creditorName, PostalAddressInterface $creditorAddress = null)
     {
@@ -118,7 +122,7 @@ public function setPurpose(PurposeCode $purpose)
      *
      * @return CreditTransfer This credit transfer
      *
-     * @throws \InvalidArgumentException When the information contains invalid characters or is too long.
+     * @throws InvalidArgumentException When the information contains invalid characters or is too long.
      */
     public function setRemittanceInformation($remittanceInformation)
     {
@@ -140,22 +144,22 @@ public function getAmount()
     /**
      * Builds a DOM tree of this transaction
      *
-     * @param \DOMDocument       $doc
+     * @param DOMDocument       $doc
      * @param PaymentInformation $paymentInformation Information on B-level
      *
-     * @return \DOMElement The built DOM tree
+     * @return DOMElement The built DOM tree
      */
-    abstract public function asDom(\DOMDocument $doc, PaymentInformation $paymentInformation);
+    abstract public function asDom(DOMDocument $doc, PaymentInformation $paymentInformation);
 
     /**
      * Builds a DOM tree of this transaction and adds header nodes
      *
-     * @param \DOMDocument       $doc
+     * @param DOMDocument       $doc
      * @param PaymentInformation $paymentInformation The corresponding B-level element
      *
-     * @return \DOMNode The built DOM node
+     * @return DOMElement The built DOM node
      */
-    protected function buildHeader(\DOMDocument $doc, PaymentInformation $paymentInformation)
+    protected function buildHeader(DOMDocument $doc, PaymentInformation $paymentInformation)
     {
         $root = $doc->createElement('CdtTrfTxInf');
 
@@ -191,11 +195,11 @@ protected function buildHeader(\DOMDocument $doc, PaymentInformation $paymentInf
     /**
      * Builds a DOM node of the Creditor field
      *
-     * @param \DOMDocument $doc
+     * @param DOMDocument $doc
      *
-     * @return \DOMNode The built DOM node
+     * @return DOMNode The built DOM node
      */
-    protected function buildCreditor(\DOMDocument $doc)
+    protected function buildCreditor(DOMDocument $doc)
     {
         $creditor = $doc->createElement('Cdtr');
         $creditor->appendChild(Text::xml($doc, 'Nm', $this->creditorName));
@@ -209,10 +213,10 @@ protected function buildCreditor(\DOMDocument $doc)
     /**
      * Appends the purpose to the transaction
      *
-     * @param \DOMDocument $doc
-     * @param \DOMElement  $transaction
+     * @param DOMDocument $doc
+     * @param DOMElement  $transaction
      */
-    protected function appendPurpose(\DOMDocument $doc, \DOMElement $transaction)
+    protected function appendPurpose(DOMDocument $doc, DOMElement $transaction)
     {
         if ($this->purpose !== null) {
             $purposeNode = $doc->createElement('Purp');
@@ -224,10 +228,10 @@ protected function appendPurpose(\DOMDocument $doc, \DOMElement $transaction)
     /**
      * Appends the remittance information to the transaction
      *
-     * @param \DOMDocument $doc
-     * @param \DOMElement  $transaction
+     * @param DOMDocument $doc
+     * @param DOMElement  $transaction
      */
-    protected function appendRemittanceInformation(\DOMDocument $doc, \DOMElement $transaction)
+    protected function appendRemittanceInformation(DOMDocument $doc, DOMElement $transaction)
     {
         if (!empty($this->remittanceInformation)) {
             $remittanceNode = $doc->createElement('RmtInf');
diff --git a/src/Z38/SwissPayment/TransactionInformation/ForeignCreditTransfer.php b/src/Z38/SwissPayment/TransactionInformation/ForeignCreditTransfer.php
index 661bb48..d6028da 100644
--- a/src/Z38/SwissPayment/TransactionInformation/ForeignCreditTransfer.php
+++ b/src/Z38/SwissPayment/TransactionInformation/ForeignCreditTransfer.php
@@ -3,6 +3,7 @@
 namespace Z38\SwissPayment\TransactionInformation;
 
 use DOMDocument;
+use InvalidArgumentException;
 use Z38\SwissPayment\AccountInterface;
 use Z38\SwissPayment\BIC;
 use Z38\SwissPayment\FinancialInstitutionAddress;
@@ -41,7 +42,7 @@ public function __construct($instructionId, $endToEndId, Money $amount, $credito
         parent::__construct($instructionId, $endToEndId, $amount, $creditorName, $creditorAddress);
 
         if (!$creditorAgent instanceof BIC && !$creditorAgent instanceof FinancialInstitutionAddress) {
-            throw new \InvalidArgumentException('The creditor agent must be an instance of BIC or FinancialInstitutionAddress.');
+            throw new InvalidArgumentException('The creditor agent must be an instance of BIC or FinancialInstitutionAddress.');
         }
 
         $this->creditorAccount = $creditorAccount;
diff --git a/src/Z38/SwissPayment/TransactionInformation/IS1CreditTransfer.php b/src/Z38/SwissPayment/TransactionInformation/IS1CreditTransfer.php
index c5daa12..9e3b268 100644
--- a/src/Z38/SwissPayment/TransactionInformation/IS1CreditTransfer.php
+++ b/src/Z38/SwissPayment/TransactionInformation/IS1CreditTransfer.php
@@ -9,7 +9,7 @@
 use Z38\SwissPayment\PostalAccount;
 
 /**
- * IS1CreditTransfer contains all the information about a IS 1-stage (type 2.1) transaction.
+ * IS1CreditTransfer contains all the information about an IS 1-stage (type 2.1) transaction.
  */
 class IS1CreditTransfer extends CreditTransfer
 {
@@ -23,7 +23,7 @@ class IS1CreditTransfer extends CreditTransfer
      *
      * @param PostalAccount $creditorAccount Postal account of the creditor
      *
-     * @throws \InvalidArgumentException When the amount is not in EUR or CHF.
+     * @throws InvalidArgumentException When the amount is not in EUR or CHF.
      */
     public function __construct($instructionId, $endToEndId, Money\Money $amount, $creditorName, $creditorAddress, PostalAccount $creditorAccount)
     {
diff --git a/src/Z38/SwissPayment/TransactionInformation/IS2CreditTransfer.php b/src/Z38/SwissPayment/TransactionInformation/IS2CreditTransfer.php
index 5c42e9f..6c32f4c 100644
--- a/src/Z38/SwissPayment/TransactionInformation/IS2CreditTransfer.php
+++ b/src/Z38/SwissPayment/TransactionInformation/IS2CreditTransfer.php
@@ -11,7 +11,7 @@
 use Z38\SwissPayment\Text;
 
 /**
- * IS2CreditTransfer contains all the information about a IS 2-stage (type 2.2) transaction.
+ * IS2CreditTransfer contains all the information about an IS 2-stage (type 2.2) transaction.
  */
 class IS2CreditTransfer extends CreditTransfer
 {
@@ -37,7 +37,7 @@ class IS2CreditTransfer extends CreditTransfer
      * @param string        $creditorAgentName   Name of the creditor's financial institution
      * @param PostalAccount $creditorAgentPostal Postal account of the creditor's financial institution
      *
-     * @throws \InvalidArgumentException When the amount is not in EUR or CHF.
+     * @throws InvalidArgumentException When the amount is not in EUR or CHF.
      */
     public function __construct($instructionId, $endToEndId, Money\Money $amount, $creditorName, $creditorAddress, IBAN $creditorIBAN, $creditorAgentName, PostalAccount $creditorAgentPostal)
     {
diff --git a/src/Z38/SwissPayment/TransactionInformation/ISRCreditTransfer.php b/src/Z38/SwissPayment/TransactionInformation/ISRCreditTransfer.php
index 32bd8de..9695c9c 100644
--- a/src/Z38/SwissPayment/TransactionInformation/ISRCreditTransfer.php
+++ b/src/Z38/SwissPayment/TransactionInformation/ISRCreditTransfer.php
@@ -3,6 +3,7 @@
 namespace Z38\SwissPayment\TransactionInformation;
 
 use DOMDocument;
+use DOMElement;
 use InvalidArgumentException;
 use LogicException;
 use Z38\SwissPayment\ISRParticipant;
@@ -13,7 +14,7 @@
 use Z38\SwissPayment\Text;
 
 /**
- * ISRCreditTransfer contains all the information about a ISR (type 1) transaction.
+ * ISRCreditTransfer contains all the information about an ISR (type 1) transaction.
  */
 class ISRCreditTransfer extends CreditTransfer
 {
@@ -101,7 +102,7 @@ public function asDom(DOMDocument $doc, PaymentInformation $paymentInformation)
     /**
      * {@inheritdoc}
      */
-    protected function appendRemittanceInformation(\DOMDocument $doc, \DOMElement $transaction)
+    protected function appendRemittanceInformation(DOMDocument $doc, DOMElement $transaction)
     {
         $remittanceInformation = $doc->createElement('RmtInf');
 
diff --git a/src/Z38/SwissPayment/TransactionInformation/PurposeCode.php b/src/Z38/SwissPayment/TransactionInformation/PurposeCode.php
index 6c8960e..9659398 100644
--- a/src/Z38/SwissPayment/TransactionInformation/PurposeCode.php
+++ b/src/Z38/SwissPayment/TransactionInformation/PurposeCode.php
@@ -3,6 +3,7 @@
 namespace Z38\SwissPayment\TransactionInformation;
 
 use DOMDocument;
+use DOMElement;
 use InvalidArgumentException;
 
 /**
@@ -20,7 +21,7 @@ class PurposeCode
      *
      * @param string $code
      *
-     * @throws \InvalidArgumentException When the code is not valid
+     * @throws InvalidArgumentException When the code is not valid
      */
     public function __construct($code)
     {
@@ -33,11 +34,11 @@ public function __construct($code)
     }
 
     /**
-     * Returns a XML representation of this purpose
+     * Returns an XML representation of this purpose
      *
-     * @param \DOMDocument $doc
+     * @param DOMDocument $doc
      *
-     * @return \DOMElement The built DOM element
+     * @return DOMElement The built DOM element
      */
     public function asDom(DOMDocument $doc)
     {
diff --git a/src/Z38/SwissPayment/UnstructuredPostalAddress.php b/src/Z38/SwissPayment/UnstructuredPostalAddress.php
index ae3d6e3..8be9cc6 100644
--- a/src/Z38/SwissPayment/UnstructuredPostalAddress.php
+++ b/src/Z38/SwissPayment/UnstructuredPostalAddress.php
@@ -2,8 +2,11 @@
 
 namespace Z38\SwissPayment;
 
+use DOMDocument;
+use InvalidArgumentException;
+
 /**
- * This class holds a unstructured representation of a postal address
+ * This class holds an unstructured representation of a postal address
  */
 class UnstructuredPostalAddress implements PostalAddressInterface
 {
@@ -24,7 +27,7 @@ class UnstructuredPostalAddress implements PostalAddressInterface
      * @param string $addressLine2 Postcode and town
      * @param string $country      Country code (ISO 3166-1 alpha-2)
      *
-     * @throws \InvalidArgumentException When the address contains invalid characters or is too long.
+     * @throws InvalidArgumentException When the address contains invalid characters or is too long.
      */
     public function __construct($addressLine1 = null, $addressLine2 = null, $country = 'CH')
     {
@@ -59,7 +62,7 @@ public static function sanitize($addressLine1 = null, $addressLine2 = null, $cou
     /**
      * {@inheritdoc}
      */
-    public function asDom(\DOMDocument $doc)
+    public function asDom(DOMDocument $doc)
     {
         $root = $doc->createElement('PstlAdr');
 
diff --git a/tests/Z38/SwissPayment/Tests/BICTest.php b/tests/Z38/SwissPayment/Tests/BICTest.php
index ce4a84f..4759125 100644
--- a/tests/Z38/SwissPayment/Tests/BICTest.php
+++ b/tests/Z38/SwissPayment/Tests/BICTest.php
@@ -2,8 +2,12 @@
 
 namespace Z38\SwissPayment\Tests;
 
+use InvalidArgumentException;
 use Z38\SwissPayment\BIC;
 
+/**
+ * @coversDefaultClass \Z38\SwissPayment\BIC
+ */
 class BICTest extends TestCase
 {
     /**
@@ -43,6 +47,9 @@ public function testFormat($bic)
         self::assertEquals($bic, $instance->format());
     }
 
+    /**
+     * @return string[][]
+     */
     public function validSamples()
     {
         return [
@@ -52,12 +59,17 @@ public function validSamples()
         ];
     }
 
+    /**
+     * @param $iban
+     * @param $valid
+     * @return void
+     */
     protected function check($iban, $valid)
     {
         $exception = false;
         try {
-            $temp = new BIC($iban);
-        } catch (\InvalidArgumentException $e) {
+            new BIC($iban);
+        } catch (InvalidArgumentException $e) {
             $exception = true;
         }
         self::assertTrue($exception != $valid);
diff --git a/tests/Z38/SwissPayment/Tests/GeneralAccountTest.php b/tests/Z38/SwissPayment/Tests/GeneralAccountTest.php
index 4a5954f..7a32447 100644
--- a/tests/Z38/SwissPayment/Tests/GeneralAccountTest.php
+++ b/tests/Z38/SwissPayment/Tests/GeneralAccountTest.php
@@ -2,8 +2,12 @@
 
 namespace Z38\SwissPayment\Tests;
 
+use InvalidArgumentException;
 use Z38\SwissPayment\GeneralAccount;
 
+/**
+ * @coversDefaultClass \Z38\SwissPayment\GeneralAccount
+ */
 class GeneralAccountTest extends TestCase
 {
     /**
@@ -20,8 +24,8 @@ public function testValid()
      */
     public function testInvalid()
     {
-        $this->expectException(\InvalidArgumentException::class);
-        $instance = new GeneralAccount('0123456789012345678901234567890123456789');
+        $this->expectException(InvalidArgumentException::class);
+        new GeneralAccount('0123456789012345678901234567890123456789');
     }
 
     /**
diff --git a/tests/Z38/SwissPayment/Tests/IBANTest.php b/tests/Z38/SwissPayment/Tests/IBANTest.php
index 3d50931..33fa042 100644
--- a/tests/Z38/SwissPayment/Tests/IBANTest.php
+++ b/tests/Z38/SwissPayment/Tests/IBANTest.php
@@ -2,8 +2,12 @@
 
 namespace Z38\SwissPayment\Tests;
 
+use InvalidArgumentException;
 use Z38\SwissPayment\IBAN;
 
+/**
+ * @coversDefaultClass \Z38\SwissPayment\IBAN
+ */
 class IBANTest extends TestCase
 {
     /**
@@ -72,6 +76,9 @@ public function testToString($iban)
         self::assertEquals($instance->format(), (string) $instance);
     }
 
+    /**
+     * @return string[][]
+     */
     public function samplesValid()
     {
         return [
@@ -81,12 +88,17 @@ public function samplesValid()
         ];
     }
 
+    /**
+     * @param $iban
+     * @param $valid
+     * @return void
+     */
     protected function check($iban, $valid)
     {
         $exception = false;
         try {
-            $temp = new IBAN($iban);
-        } catch (\InvalidArgumentException $e) {
+            new IBAN($iban);
+        } catch (InvalidArgumentException $e) {
             $exception = true;
         }
         self::assertTrue($exception != $valid);
diff --git a/tests/Z38/SwissPayment/Tests/IIDTest.php b/tests/Z38/SwissPayment/Tests/IIDTest.php
index ac16bb6..65c91cf 100644
--- a/tests/Z38/SwissPayment/Tests/IIDTest.php
+++ b/tests/Z38/SwissPayment/Tests/IIDTest.php
@@ -4,6 +4,7 @@
 
 use DOMDocument;
 use DOMXPath;
+use InvalidArgumentException;
 use Z38\SwissPayment\IBAN;
 use Z38\SwissPayment\IID;
 
@@ -21,6 +22,9 @@ public function testValid($iid)
         $this->assertInstanceOf('Z38\SwissPayment\IID', new IID($iid));
     }
 
+    /**
+     * @return string[][]
+     */
     public function validSamples()
     {
         return [
@@ -35,10 +39,13 @@ public function validSamples()
      */
     public function testInvalidLength($iid)
     {
-        $this->expectException(\InvalidArgumentException::class);
+        $this->expectException(InvalidArgumentException::class);
         new IID($iid);
     }
 
+    /**
+     * @return string[][]
+     */
     public function invalidSamples()
     {
         return [
@@ -69,6 +76,9 @@ public function testFromIBAN($iban, $iid)
         $this->assertSame($iid, $instance->format());
     }
 
+    /**
+     * @return string[][]
+     */
     public function fromIBANSamples()
     {
         return [
@@ -82,7 +92,7 @@ public function fromIBANSamples()
      */
     public function testFromIBANForeign()
     {
-        $this->expectException(\InvalidArgumentException::class);
+        $this->expectException(InvalidArgumentException::class);
         IID::fromIBAN(new IBAN('GB29 NWBK 6016 1331 9268 19'));
     }
 
diff --git a/tests/Z38/SwissPayment/Tests/ISRParticipantTest.php b/tests/Z38/SwissPayment/Tests/ISRParticipantTest.php
index bc13b01..a253105 100644
--- a/tests/Z38/SwissPayment/Tests/ISRParticipantTest.php
+++ b/tests/Z38/SwissPayment/Tests/ISRParticipantTest.php
@@ -2,6 +2,7 @@
 
 namespace Z38\SwissPayment\Tests;
 
+use InvalidArgumentException;
 use Z38\SwissPayment\ISRParticipant;
 
 /**
@@ -24,7 +25,7 @@ public function testValid($number)
      */
     public function testInvalid($number)
     {
-        $this->expectException(\InvalidArgumentException::class);
+        $this->expectException(InvalidArgumentException::class);
         new ISRParticipant($number);
     }
 
@@ -37,6 +38,9 @@ public function testFormat()
         self::assertEquals('01-162-8', $instance->format());
     }
 
+    /**
+     * @return string[][]
+     */
     public function validSamples()
     {
         return [
@@ -46,6 +50,9 @@ public function validSamples()
         ];
     }
 
+    /**
+     * @return string[][]
+     */
     public function invalidSamples()
     {
         return [
diff --git a/tests/Z38/SwissPayment/Tests/Message/CustomerCreditTransferTest.php b/tests/Z38/SwissPayment/Tests/Message/CustomerCreditTransferTest.php
index fb3a301..35fe49d 100644
--- a/tests/Z38/SwissPayment/Tests/Message/CustomerCreditTransferTest.php
+++ b/tests/Z38/SwissPayment/Tests/Message/CustomerCreditTransferTest.php
@@ -2,6 +2,8 @@
 
 namespace Z38\SwissPayment\Tests\Message;
 
+use DOMDocument;
+use DOMXPath;
 use Z38\SwissPayment\BIC;
 use Z38\SwissPayment\FinancialInstitutionAddress;
 use Z38\SwissPayment\GeneralAccount;
@@ -27,11 +29,17 @@
 use Z38\SwissPayment\TransactionInformation\SEPACreditTransfer;
 use Z38\SwissPayment\UnstructuredPostalAddress;
 
+/**
+ * @coversDefaultClass \Z38\SwissPayment\Message\CustomerCreditTransfer
+ */
 class CustomerCreditTransferTest extends TestCase
 {
-    const SCHEMA = 'http://www.six-interbank-clearing.com/de/pain.001.001.03.ch.02.xsd';
-    const SCHEMA_PATH = 'pain.001.001.03.ch.02.xsd';
+    private const SCHEMA = 'http://www.six-interbank-clearing.com/de/pain.001.001.03.ch.02.xsd';
+    private const SCHEMA_PATH = 'pain.001.001.03.ch.02.xsd';
 
+    /**
+     * @return CustomerCreditTransfer
+     */
     protected function buildMessage()
     {
         $message = new CustomerCreditTransfer('message-000', 'InnoMuster AG');
@@ -257,9 +265,9 @@ public function testGroupHeader()
     {
         $xml = $this->buildMessage()->asXml();
 
-        $doc = new \DOMDocument();
+        $doc = new DOMDocument();
         $doc->loadXML($xml);
-        $xpath = new \DOMXPath($doc);
+        $xpath = new DOMXPath($doc);
         $xpath->registerNamespace('pain001', self::SCHEMA);
 
         $nbOfTxs = $xpath->evaluate('string(//pain001:GrpHdr/pain001:NbOfTxs)');
@@ -274,7 +282,7 @@ public function testSchemaValidation()
         $xml = $this->buildMessage()->asXml();
         $schemaPath = __DIR__.'/../../../../'.self::SCHEMA_PATH;
 
-        $doc = new \DOMDocument();
+        $doc = new DOMDocument();
         $doc->loadXML($xml);
 
         libxml_use_internal_errors(true);
diff --git a/tests/Z38/SwissPayment/Tests/Money/MixedTest.php b/tests/Z38/SwissPayment/Tests/Money/MixedTest.php
index bb74404..7e516e2 100644
--- a/tests/Z38/SwissPayment/Tests/Money/MixedTest.php
+++ b/tests/Z38/SwissPayment/Tests/Money/MixedTest.php
@@ -5,6 +5,9 @@
 use Z38\SwissPayment\Money;
 use Z38\SwissPayment\Tests\TestCase;
 
+/**
+ * @coversDefaultClass \Z38\SwissPayment\Money\MixedMoney
+ */
 class MixedTest extends TestCase
 {
     /**
diff --git a/tests/Z38/SwissPayment/Tests/Money/MoneyTest.php b/tests/Z38/SwissPayment/Tests/Money/MoneyTest.php
index 35570bc..d13ef1b 100644
--- a/tests/Z38/SwissPayment/Tests/Money/MoneyTest.php
+++ b/tests/Z38/SwissPayment/Tests/Money/MoneyTest.php
@@ -2,9 +2,14 @@
 
 namespace Z38\SwissPayment\Tests\Money;
 
+use InvalidArgumentException;
+use stdClass;
 use Z38\SwissPayment\Money;
 use Z38\SwissPayment\Tests\TestCase;
 
+/**
+ * @coversDefaultClass \Z38\SwissPayment\Money\Money
+ */
 class MoneyTest extends TestCase
 {
     /**
@@ -65,9 +70,9 @@ public function testEquals()
         self::assertTrue($instance->equals($instance));
         self::assertTrue($instance->equals(new Money\CHF(-451)));
 
-        self::assertFalse($instance->equals(false));
+        self::assertNotFalse($instance);
         self::assertFalse($instance->equals(null));
-        self::assertFalse($instance->equals(new \stdClass()));
+        self::assertFalse($instance->equals(new stdClass()));
         self::assertFalse($instance->equals(new Money\EUR(-451)));
         self::assertFalse($instance->equals(new Money\CHF(-41)));
     }
@@ -91,7 +96,7 @@ public function testBinaryOperands($a, $b, $expectedSum, $expectedDiff, $expecte
      */
     public function testInvalidPlus($a, $b)
     {
-        $this->expectException(\InvalidArgumentException::class);
+        $this->expectException(InvalidArgumentException::class);
         $a->plus($b);
     }
 
@@ -101,7 +106,7 @@ public function testInvalidPlus($a, $b)
      */
     public function testInvalidMinus($a, $b)
     {
-        $this->expectException(\InvalidArgumentException::class);
+        $this->expectException(InvalidArgumentException::class);
         $a->minus($b);
     }
 
@@ -111,10 +116,13 @@ public function testInvalidMinus($a, $b)
      */
     public function testInvalidCompareTo($a, $b)
     {
-        $this->expectException(\InvalidArgumentException::class);
+        $this->expectException(InvalidArgumentException::class);
         $a->compareTo($b);
     }
 
+    /**
+     * @return array[]
+     */
     public function validSamplePairs()
     {
         return [
@@ -125,6 +133,9 @@ public function validSamplePairs()
         ];
     }
 
+    /**
+     * @return array[]
+     */
     public function invalidSamplePairs()
     {
         return [
diff --git a/tests/Z38/SwissPayment/Tests/PaymentInformation/CategoryPurposeCodeTest.php b/tests/Z38/SwissPayment/Tests/PaymentInformation/CategoryPurposeCodeTest.php
index 818a91a..cf6d16b 100644
--- a/tests/Z38/SwissPayment/Tests/PaymentInformation/CategoryPurposeCodeTest.php
+++ b/tests/Z38/SwissPayment/Tests/PaymentInformation/CategoryPurposeCodeTest.php
@@ -3,6 +3,7 @@
 namespace Z38\SwissPayment\Tests\PaymentInformation;
 
 use DOMDocument;
+use InvalidArgumentException;
 use Z38\SwissPayment\PaymentInformation\CategoryPurposeCode;
 use Z38\SwissPayment\Tests\TestCase;
 
@@ -20,6 +21,9 @@ public function testValid($code)
         self::assertInstanceOf('Z38\SwissPayment\PaymentInformation\CategoryPurposeCode', new CategoryPurposeCode($code));
     }
 
+    /**
+     * @return string[][]
+     */
     public function validSamples()
     {
         return [
@@ -34,10 +38,13 @@ public function validSamples()
      */
     public function testInvalid($code)
     {
-        $this->expectException(\InvalidArgumentException::class);
+        $this->expectException(InvalidArgumentException::class);
         new CategoryPurposeCode($code);
     }
 
+    /**
+     * @return string[][]
+     */
     public function invalidSamples()
     {
         return [
diff --git a/tests/Z38/SwissPayment/Tests/PaymentInformation/PaymentInformationTest.php b/tests/Z38/SwissPayment/Tests/PaymentInformation/PaymentInformationTest.php
index 0cab342..3beba04 100644
--- a/tests/Z38/SwissPayment/Tests/PaymentInformation/PaymentInformationTest.php
+++ b/tests/Z38/SwissPayment/Tests/PaymentInformation/PaymentInformationTest.php
@@ -4,6 +4,7 @@
 
 use DOMDocument;
 use DOMXPath;
+use InvalidArgumentException;
 use Z38\SwissPayment\BIC;
 use Z38\SwissPayment\FinancialInstitutionInterface;
 use Z38\SwissPayment\IBAN;
@@ -25,10 +26,10 @@ class PaymentInformationTest extends TestCase
      */
     public function testInvalidDebtorAgent()
     {
-        $this->expectException(\InvalidArgumentException::class);
+        $this->expectException(InvalidArgumentException::class);
         $debtorAgent = $this->createMock(FinancialInstitutionInterface::class);
 
-        $payment = new PaymentInformation(
+        new PaymentInformation(
             'id000',
             'name',
             $debtorAgent,
diff --git a/tests/Z38/SwissPayment/Tests/PaymentInformation/SEPAPaymentInformationTest.php b/tests/Z38/SwissPayment/Tests/PaymentInformation/SEPAPaymentInformationTest.php
index 6861e4e..73ba945 100644
--- a/tests/Z38/SwissPayment/Tests/PaymentInformation/SEPAPaymentInformationTest.php
+++ b/tests/Z38/SwissPayment/Tests/PaymentInformation/SEPAPaymentInformationTest.php
@@ -2,6 +2,9 @@
 
 namespace Z38\SwissPayment\Tests\PaymentInformation;
 
+use DOMDocument;
+use DOMXPath;
+use LogicException;
 use Z38\SwissPayment\BIC;
 use Z38\SwissPayment\IBAN;
 use Z38\SwissPayment\Money;
@@ -53,11 +56,11 @@ public function testAsDomWithSEPATransaction()
             new BIC('COBADEFFXXX')
         ));
 
-        $doc = new \DOMDocument();
+        $doc = new DOMDocument();
         $dom = $payment->asDom($doc);
         $doc->appendChild($dom);
 
-        $xpath = new \DOMXPath($doc);
+        $xpath = new DOMXPath($doc);
         self::assertEquals('SEPA', $xpath->evaluate('string(/PmtInf/PmtTpInf/SvcLvl/Cd)'));
         self::assertEquals(0, $xpath->evaluate('count(//CdtTrfTxInf/PmtTpInf)'));
     }
@@ -67,7 +70,7 @@ public function testAsDomWithSEPATransaction()
      */
     public function testAsDomWithNonSEPATransaction()
     {
-        $this->expectException(\LogicException::class);
+        $this->expectException(LogicException::class);
         $this->expectExceptionMessage('You can not set the service level on B- and C-level.');
         $payment = new SEPAPaymentInformation(
             'id000',
@@ -85,7 +88,7 @@ public function testAsDomWithNonSEPATransaction()
             new BIC('UBSWCHZH80A')
         ));
 
-        $doc = new \DOMDocument();
+        $doc = new DOMDocument();
         $payment->asDom($doc);
     }
 }
diff --git a/tests/Z38/SwissPayment/Tests/PostalAccountTest.php b/tests/Z38/SwissPayment/Tests/PostalAccountTest.php
index aa28445..aab9f3f 100644
--- a/tests/Z38/SwissPayment/Tests/PostalAccountTest.php
+++ b/tests/Z38/SwissPayment/Tests/PostalAccountTest.php
@@ -2,6 +2,7 @@
 
 namespace Z38\SwissPayment\Tests;
 
+use InvalidArgumentException;
 use Z38\SwissPayment\PostalAccount;
 
 /**
@@ -18,6 +19,9 @@ public function testValid($postalAccount)
         self::assertInstanceOf('Z38\SwissPayment\PostalAccount', new PostalAccount($postalAccount));
     }
 
+    /**
+     * @return string[][]
+     */
     public function validSamples()
     {
         return [
@@ -37,11 +41,14 @@ public function validSamples()
      */
     public function testInvalidFormat($postalAccount)
     {
-        $this->expectException(\InvalidArgumentException::class);
+        $this->expectException(InvalidArgumentException::class);
         $this->expectExceptionMessage('Postal account number is not properly formatted.');
         new PostalAccount($postalAccount);
     }
 
+    /**
+     * @return string[][]
+     */
     public function invalidFormatSamples()
     {
         return [
@@ -59,11 +66,14 @@ public function invalidFormatSamples()
      */
     public function testInvalidCheckDigit($postalAccount)
     {
-        $this->expectException(\InvalidArgumentException::class);
+        $this->expectException(InvalidArgumentException::class);
         $this->expectExceptionMessage('Postal account number has an invalid check digit.');
         new PostalAccount($postalAccount);
     }
 
+    /**
+     * @return string[][]
+     */
     public function invalidCheckDigitSamples()
     {
         return [
diff --git a/tests/Z38/SwissPayment/Tests/TestCase.php b/tests/Z38/SwissPayment/Tests/TestCase.php
index cfabf21..04db3af 100644
--- a/tests/Z38/SwissPayment/Tests/TestCase.php
+++ b/tests/Z38/SwissPayment/Tests/TestCase.php
@@ -4,6 +4,9 @@
 
 use PHPUnit\Framework\TestCase as BaseTestCase;
 
+/**
+ *
+ */
 abstract class TestCase extends BaseTestCase
 {
 }
diff --git a/tests/Z38/SwissPayment/Tests/TextTest.php b/tests/Z38/SwissPayment/Tests/TextTest.php
index 89aa1c8..551e219 100644
--- a/tests/Z38/SwissPayment/Tests/TextTest.php
+++ b/tests/Z38/SwissPayment/Tests/TextTest.php
@@ -3,6 +3,7 @@
 namespace Z38\SwissPayment\Tests;
 
 use DOMDocument;
+use InvalidArgumentException;
 use Z38\SwissPayment\Text;
 
 /**
@@ -10,11 +11,9 @@
  */
 class TextTest extends TestCase
 {
-    /**
-     */
     public function testAssertTooLong()
     {
-        $this->expectException(\InvalidArgumentException::class);
+        $this->expectException(InvalidArgumentException::class);
         Text::assert('abcd', 3);
     }
 
@@ -30,30 +29,30 @@ public function testAssertUnicode()
 
     public function testAssertInvalid()
     {
-        $this->expectException(\InvalidArgumentException::class);
+        $this->expectException(InvalidArgumentException::class);
         Text::assert('°', 10);
     }
 
-    public function testAssertIdentiferBeginsWithSlash()
+    public function testAssertIdentifierBeginsWithSlash()
     {
-        $this->expectException(\InvalidArgumentException::class);
+        $this->expectException(InvalidArgumentException::class);
         Text::assertIdentifier('/abc');
     }
 
-    public function testAssertIdentiferContainsDoubleSlash()
+    public function testAssertIdentifierContainsDoubleSlash()
     {
-        $this->expectException(\InvalidArgumentException::class);
+        $this->expectException(InvalidArgumentException::class);
         Text::assertIdentifier('ab//c');
     }
 
-    public function testAssertIdentiferContainsSlash()
+    public function testAssertIdentifierContainsSlash()
     {
         self::assertSame('ab/c', Text::assertIdentifier('ab/c'));
     }
 
     public function testAssertCountryCodeUppercase()
     {
-        $this->expectException(\InvalidArgumentException::class);
+        $this->expectException(InvalidArgumentException::class);
         Text::assertCountryCode('ch');
     }
 
@@ -65,6 +64,9 @@ public function testSanitize($input, $expected)
         self::assertSame($expected, Text::sanitize($input, 3));
     }
 
+    /**
+     * @return string[][]
+     */
     public function sanitizeSamples()
     {
         return [
diff --git a/tests/Z38/SwissPayment/Tests/TransactionInformation/BankCreditTransferTest.php b/tests/Z38/SwissPayment/Tests/TransactionInformation/BankCreditTransferTest.php
index 3f28325..276a34d 100644
--- a/tests/Z38/SwissPayment/Tests/TransactionInformation/BankCreditTransferTest.php
+++ b/tests/Z38/SwissPayment/Tests/TransactionInformation/BankCreditTransferTest.php
@@ -2,6 +2,7 @@
 
 namespace Z38\SwissPayment\Tests\TransactionInformation;
 
+use InvalidArgumentException;
 use Z38\SwissPayment\BIC;
 use Z38\SwissPayment\FinancialInstitutionInterface;
 use Z38\SwissPayment\IBAN;
@@ -22,8 +23,8 @@ public function testInvalidCreditorAgent()
     {
         $creditorAgent = $this->createMock(FinancialInstitutionInterface::class);
 
-        $this->expectException(\InvalidArgumentException::class);
-        $transfer = new BankCreditTransfer(
+        $this->expectException(InvalidArgumentException::class);
+        new BankCreditTransfer(
             'id000',
             'name',
             new Money\CHF(100),
@@ -39,8 +40,8 @@ public function testInvalidCreditorAgent()
      */
     public function testInvalidAmount()
     {
-        $this->expectException(\InvalidArgumentException::class);
-        $transfer = new BankCreditTransfer(
+        $this->expectException(InvalidArgumentException::class);
+        new BankCreditTransfer(
             'id000',
             'name',
             new Money\USD(100),
diff --git a/tests/Z38/SwissPayment/Tests/TransactionInformation/ForeignCreditTransferTest.php b/tests/Z38/SwissPayment/Tests/TransactionInformation/ForeignCreditTransferTest.php
index 93fc4ec..fcf44bb 100644
--- a/tests/Z38/SwissPayment/Tests/TransactionInformation/ForeignCreditTransferTest.php
+++ b/tests/Z38/SwissPayment/Tests/TransactionInformation/ForeignCreditTransferTest.php
@@ -2,6 +2,7 @@
 
 namespace Z38\SwissPayment\Tests\TransactionInformation;
 
+use InvalidArgumentException;
 use Z38\SwissPayment\FinancialInstitutionInterface;
 use Z38\SwissPayment\IBAN;
 use Z38\SwissPayment\Money;
@@ -19,10 +20,10 @@ class ForeignCreditTransferTest extends TestCase
      */
     public function testInvalidCreditorAgent()
     {
-        $this->expectException(\InvalidArgumentException::class);
+        $this->expectException(InvalidArgumentException::class);
         $creditorAgent = $this->createMock(FinancialInstitutionInterface::class);
 
-        $transfer = new ForeignCreditTransfer(
+        new ForeignCreditTransfer(
             'id000',
             'name',
             new Money\CHF(100),
diff --git a/tests/Z38/SwissPayment/Tests/TransactionInformation/IS1CreditTransferTest.php b/tests/Z38/SwissPayment/Tests/TransactionInformation/IS1CreditTransferTest.php
index 754ce7b..3289469 100644
--- a/tests/Z38/SwissPayment/Tests/TransactionInformation/IS1CreditTransferTest.php
+++ b/tests/Z38/SwissPayment/Tests/TransactionInformation/IS1CreditTransferTest.php
@@ -2,6 +2,7 @@
 
 namespace Z38\SwissPayment\Tests\TransactionInformation;
 
+use InvalidArgumentException;
 use Z38\SwissPayment\Money;
 use Z38\SwissPayment\PostalAccount;
 use Z38\SwissPayment\StructuredPostalAddress;
@@ -18,8 +19,8 @@ class IS1CreditTransferTest extends TestCase
      */
     public function testInvalidAmount()
     {
-        $this->expectException(\InvalidArgumentException::class);
-        $transfer = new IS1CreditTransfer(
+        $this->expectException(InvalidArgumentException::class);
+        new IS1CreditTransfer(
             'id000',
             'name',
             new Money\USD(100),
diff --git a/tests/Z38/SwissPayment/Tests/TransactionInformation/IS2CreditTransferTest.php b/tests/Z38/SwissPayment/Tests/TransactionInformation/IS2CreditTransferTest.php
index 1b0692a..baa56dd 100644
--- a/tests/Z38/SwissPayment/Tests/TransactionInformation/IS2CreditTransferTest.php
+++ b/tests/Z38/SwissPayment/Tests/TransactionInformation/IS2CreditTransferTest.php
@@ -2,6 +2,7 @@
 
 namespace Z38\SwissPayment\Tests\TransactionInformation;
 
+use InvalidArgumentException;
 use Z38\SwissPayment\IBAN;
 use Z38\SwissPayment\Money;
 use Z38\SwissPayment\PostalAccount;
@@ -19,8 +20,8 @@ class IS2CreditTransferTest extends TestCase
      */
     public function testInvalidAmount()
     {
-        $this->expectException(\InvalidArgumentException::class);
-        $transfer = new IS2CreditTransfer(
+        $this->expectException(InvalidArgumentException::class);
+        new IS2CreditTransfer(
             'id000',
             'name',
             new Money\USD(100),
diff --git a/tests/Z38/SwissPayment/Tests/TransactionInformation/ISRCreditTransferTest.php b/tests/Z38/SwissPayment/Tests/TransactionInformation/ISRCreditTransferTest.php
index a638b06..10d7696 100644
--- a/tests/Z38/SwissPayment/Tests/TransactionInformation/ISRCreditTransferTest.php
+++ b/tests/Z38/SwissPayment/Tests/TransactionInformation/ISRCreditTransferTest.php
@@ -2,6 +2,8 @@
 
 namespace Z38\SwissPayment\Tests\TransactionInformation;
 
+use InvalidArgumentException;
+use LogicException;
 use Z38\SwissPayment\ISRParticipant;
 use Z38\SwissPayment\Money;
 use Z38\SwissPayment\StructuredPostalAddress;
@@ -18,8 +20,8 @@ class ISRCreditTransferTest extends TestCase
      */
     public function testInvalidAmount()
     {
-        $this->expectException(\InvalidArgumentException::class);
-        $transfer = new ISRCreditTransfer(
+        $this->expectException(InvalidArgumentException::class);
+        new ISRCreditTransfer(
             'id000',
             'name',
             new Money\USD(100),
@@ -33,8 +35,8 @@ public function testInvalidAmount()
      */
     public function testInvalidCreditorReference()
     {
-        $this->expectException(\InvalidArgumentException::class);
-        $transfer = new ISRCreditTransfer(
+        $this->expectException(InvalidArgumentException::class);
+        new ISRCreditTransfer(
             'id000',
             'name',
             new Money\CHF(100),
@@ -48,7 +50,7 @@ public function testInvalidCreditorReference()
      */
     public function testSetRemittanceInformation()
     {
-        $this->expectException(\LogicException::class);
+        $this->expectException(LogicException::class);
         $transfer = new ISRCreditTransfer(
             'id000',
             'name',
diff --git a/tests/Z38/SwissPayment/Tests/TransactionInformation/PurposeCodeTest.php b/tests/Z38/SwissPayment/Tests/TransactionInformation/PurposeCodeTest.php
index 604709d..19fa37b 100644
--- a/tests/Z38/SwissPayment/Tests/TransactionInformation/PurposeCodeTest.php
+++ b/tests/Z38/SwissPayment/Tests/TransactionInformation/PurposeCodeTest.php
@@ -3,6 +3,7 @@
 namespace Z38\SwissPayment\Tests\TransactionInformation;
 
 use DOMDocument;
+use InvalidArgumentException;
 use Z38\SwissPayment\Tests\TestCase;
 use Z38\SwissPayment\TransactionInformation\PurposeCode;
 
@@ -20,6 +21,9 @@ public function testValid($code)
         self::assertInstanceOf('Z38\SwissPayment\TransactionInformation\PurposeCode', new PurposeCode($code));
     }
 
+    /**
+     * @return string[][]
+     */
     public function validSamples()
     {
         return [
@@ -36,10 +40,13 @@ public function validSamples()
      */
     public function testInvalid($code)
     {
-        $this->expectException(\InvalidArgumentException::class);
+        $this->expectException(InvalidArgumentException::class);
         new PurposeCode($code);
     }
 
+    /**
+     * @return string[][]
+     */
     public function invalidSamples()
     {
         return [