Code review changes.

Author: Ekman

.gitignore

@@ -1,6 +1,7 @@
 index.php
 nbproject/
 .idea/
+.php_cs.cache
 
 # Created by http://www.gitignore.io
 

.php_cs.dist

@@ -0,0 +1,14 @@
+<?php
+
+return PhpCsFixer\Config::create()
+    ->setRules([
+        '@PSR2' => true,
+        'ordered_imports' => true,
+        'phpdoc_order' => true,
+        'simplified_null_return' => false,
+        'no_unused_imports' => true,
+    ])->setFinder(
+        PhpCsFixer\Finder::create()
+            ->in(__DIR__.'/src')
+            ->in(__DIR__.'/tests')
+    );

composer.json

@@ -34,6 +34,7 @@
 		"php": "^7.1"
 	},
 	"require-dev": {
-		"phpunit/phpunit": "^6.5"
+		"phpunit/phpunit": "^6.5",
+		"friendsofphp/php-cs-fixer": "^2.10"
 	}
 }

src/Contract/LuhnAlgorithmInterface.php

@@ -1,62 +1,63 @@
-<?php
-
-/*
- * The MIT License (MIT)
- *
- * Copyright (c) 2014 Niklas Ekman
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy of
- * this software and associated documentation files (the "Software"), to deal in
- * the Software without restriction, including without limitation the rights to
- * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
- * the Software, and to permit persons to whom the Software is furnished to do so,
- * subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in all
- * copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
- * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
- * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
- * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
- * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
- */
-
-namespace Nekman\LuhnAlgorithm\Contract;
-
-/**
- * Handles the Luhn Algorithm.
- * 
- * @link http://en.wikipedia.org/wiki/Luhn_algorithm 
- */
-interface LuhnAlgorithmInterface {
-    /**
-     * Determine if a number is valid according to the Luhn Algorithm.
-     *
-     * @param NumberInterface $number The number to validate.
-     *
-     * @return bool true if number is valid, false otherwise.
-     */
-    public function isValid(NumberInterface $number): bool;
-
-    /**
-     * Calculate the check digit for an input.
-     *
-     * @param NumberInterface $number The number, without check digit, to calculate the check digit for.
-     *
-     * @return int The check digit.
-     *
-     */
-    public function calcCheckDigit(NumberInterface $number): int;
-
-    /**
-     * Calulates the checksum for number.
-     *
-     * @param NumberInterface $number The number, without check digit, to calculate the checksum for.
-     *
-     * @return int The checksum.
-     *
-     */
-    public function calcChecksum(NumberInterface $number): int;
-}
+<?php
+
+/*
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2014 Niklas Ekman
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+namespace Nekman\LuhnAlgorithm\Contract;
+
+/**
+ * Handles the Luhn Algorithm.
+ *
+ * @link http://en.wikipedia.org/wiki/Luhn_algorithm
+ */
+interface LuhnAlgorithmInterface
+{
+    /**
+     * Determine if a number is valid according to the Luhn Algorithm.
+     *
+     * @param NumberInterface $number The number to validate.
+     *
+     * @return bool true if number is valid, false otherwise.
+     */
+    public function isValid(NumberInterface $number): bool;
+
+    /**
+     * Calculate the check digit for an input.
+     *
+     * @param NumberInterface $number The number to calculate the check digit for.
+     *
+     * @return int The check digit.
+     *
+     */
+    public function calcCheckDigit(NumberInterface $number): int;
+
+    /**
+     * Calulates the checksum for number.
+     *
+     * @param NumberInterface $number The number to calculate the checksum for.
+     *
+     * @return int The checksum.
+     *
+     */
+    public function calcChecksum(NumberInterface $number): int;
+}

src/Contract/NumberInterface.php

@@ -1,46 +1,46 @@
-<?php
-
-/*
- * The MIT License (MIT)
- *
- * Copyright (c) 2014 Niklas Ekman
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy of
- * this software and associated documentation files (the "Software"), to deal in
- * the Software without restriction, including without limitation the rights to
- * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
- * the Software, and to permit persons to whom the Software is furnished to do so,
- * subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in all
- * copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
- * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
- * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
- * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
- * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
- */
-
-namespace Nekman\LuhnAlgorithm\Contract;
-
-/**
- * Describes the structure of a number in the Luhn Algorithm.
- */
-interface NumberInterface
-{
-    /**
-     * Get the number, without check digit.
-     *
-     * @return int
-     */
-    public function getNumber(): int;
-
-    /**
-     * Get the check digit for the number.
-     *
-     * @return int|null The check digit or null if it has not been calculated yet.
-     */
-    public function getCheckDigit(): ?int;
-}
+<?php
+
+/*
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2014 Niklas Ekman
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+namespace Nekman\LuhnAlgorithm\Contract;
+
+/**
+ * Describes the structure of a number in the Luhn Algorithm.
+ */
+interface NumberInterface
+{
+    /**
+     * Get the number, without check digit.
+     *
+     * @return int
+     */
+    public function getNumber(): int;
+
+    /**
+     * Get the check digit for the number.
+     *
+     * @return int|null The check digit or null if it has not been calculated yet.
+     */
+    public function getCheckDigit(): ?int;
+}

src/LuhnAlgorithm.php

@@ -31,53 +31,57 @@
 /**
  * {@inheritdoc}
  */
-class LuhnAlgorithm implements LuhnAlgorithmInterface {
-	/**
-	 * {@inheritDoc}
-	 */
-	public function isValid(NumberInterface $number): bool {
-		if ($number->getCheckDigit() === null) {
-		    throw new \InvalidArgumentException("Check digit cannot be null.");
+class LuhnAlgorithm implements LuhnAlgorithmInterface
+{
+    /**
+     * {@inheritDoc}
+     */
+    public function isValid(NumberInterface $number): bool
+    {
+        if ($number->getCheckDigit() === null) {
+            throw new \InvalidArgumentException("Check digit cannot be null.");
         }
 
         $checksum = $this->calcChecksum($number);
-		$sum = $checksum + $number->getCheckDigit();
+        $sum = $checksum + $number->getCheckDigit();
 
-		// If the checksum is divisible by 10 it is valid.
-		return ($sum % 10) === 0;
-	}
+        // If the checksum is divisible by 10 it is valid.
+        return ($sum % 10) === 0;
+    }
 
-	/**
-	 * {@inheritDoc}
-	 */
-	public function calcCheckDigit(NumberInterface $number): int {
-		$checksum = $this->calcChecksum($number);
-		
-		// Get the last digit of the checksum.
-		$checkDigit = $checksum % 10;
+    /**
+     * {@inheritDoc}
+     */
+    public function calcCheckDigit(NumberInterface $number): int
+    {
+        $checksum = $this->calcChecksum($number);
+        
+        // Get the last digit of the checksum.
+        $checkDigit = $checksum % 10;
 
-		// If the check digit is not 0, then subtract the value from 10.
-		return $checkDigit === 0
+        // If the check digit is not 0, then subtract the value from 10.
+        return $checkDigit === 0
             ? $checkDigit
             : 10 - $checkDigit;
-	}
+    }
 
-	/**
-	 * {@inheritDoc}
-	 */
-	public function calcChecksum(NumberInterface $number): int {
-		$number = (string) $number->getNumber();
-		$nDigits = strlen($number);
-		$checksum = 0;
-		$parity = $nDigits % 2;
+    /**
+     * {@inheritDoc}
+     */
+    public function calcChecksum(NumberInterface $number): int
+    {
+        $number = (string) $number->getNumber();
+        $nDigits = strlen($number);
+        $checksum = 0;
+        $parity = $nDigits % 2;
 
-		for ($i = 0; $i < $nDigits; $i++) {
-		    $digit = (int) $number[$i];
+        for ($i = 0; $i < $nDigits; $i++) {
+            $digit = (int) $number[$i];
 
-		    // Every other digit, starting from the leftmost,
+            // Every other digit, starting from the leftmost,
             // shall be doubled.
-		    if (($i % 2) !== $parity) {
-		        $digit *= 2;
+            if (($i % 2) !== $parity) {
+                $digit *= 2;
 
                 if ($digit > 9) {
                     $digit -= 9;
@@ -87,6 +91,6 @@ public function calcChecksum(NumberInterface $number): int {
             $checksum += $digit;
         }
 
-		return $checksum;
-	}
+        return $checksum;
+    }
 }