Bugfix for numbers larger than PHP_INT_MAX (#10)

* Add unit tests that should pass

* Travis fix

* Bugfix, numbers larger then INT_MAX.

* Add test for int max.

* Test new invalid argument exception.

* Fixes

Author: Ekman

.travis.yml

@@ -6,7 +6,7 @@ php:
 
 install: composer install --no-interaction --classmap-authoritative
 
-script: vendor/bin/phpunit
+script: vendor/bin/phpunit --configuration phpunit.xml
 
 notifications:
   email: false

src/Contract/NumberInterface.php

@@ -35,9 +35,9 @@ interface NumberInterface
     /**
      * Get the number, without check digit.
      *
-     * @return int
+     * @return string
      */
-    public function getNumber(): int;
+    public function getNumber(): string;
 
     /**
      * Get the check digit for the number.

src/Number.php

@@ -46,11 +46,15 @@ class Number implements NumberInterface
 
     /**
      * Input constructor.
-     * @param int $number The number.
+     * @param string $number The number.
      * @param int|null $checkDigit [Optional] The check digit for the number.
      */
-    public function __construct(int $number, ?int $checkDigit = null)
+    public function __construct(string $number, ?int $checkDigit = null)
     {
+        if (!is_numeric($number)) {
+            throw new \InvalidArgumentException("Expects \$number to be a number, \"{$number}\" given.");
+        }
+
         $this->number = $number;
         $this->checkDigit = $checkDigit;
     }
@@ -65,21 +69,25 @@ public function __construct(int $number, ?int $checkDigit = null)
      */
     public static function fromString(string $input): self
     {
-        $input = (int) preg_replace("/[^\d]/", "", $input);
+        $input = preg_replace('/[^\d]/', '', $input);
+
+        if (!is_numeric($input)) {
+            throw new \InvalidArgumentException("Expects \$input to be a number, \"{$input}\" given.");
+        }
 
         // Get the last digit.
-        $checkDigit = $input % 10;
+        $checkDigit = (int) $input[strlen($input) - 1];
 
         // Remove the last digit.
-        $number = (int) ($input / 10);
+        $number = substr($input, 0, strlen($input) - 1);
 
         return new self($number, $checkDigit);
     }
 
     /**
      * {@inheritdoc}
      */
-    public function getNumber(): int
+    public function getNumber(): string
     {
         return $this->number;
     }

tests/LuhnAlgorithmTest.php

@@ -54,9 +54,10 @@ public function testIsValid_success($number, $expected)
     public function provideIsValid_success()
     {
         return [
-            [new Number(12345, 5), true],
-            [new Number(410321920, 2), true],
-            [new Number(3199723370002, 0), true],
+            [new Number('12345', 5), true],
+            [new Number('410321920', 2), true],
+            [new Number('3199723370002', 0), true],
+            [new Number('8914800000397416568', 5), true],
         ];
     }
 

tests/NumberTest.php

@@ -31,18 +31,39 @@
 class NumberTest extends TestCase
 {
     /**
-     * @dataProvider provideWithCheckDigit_success
+     * @dataProvider provideFromString_success
      */
-    public function testWithCheckDigit_success($number, $expected)
+    public function testFromString_success($number, $expected)
     {
         $this->assertEquals($expected, Number::fromString($number));
     }
 
-    public function provideWithCheckDigit_success()
+    public function provideFromString_success()
     {
         return [
-            ["410321-9202", new Number(410321920, 2)],
-            [4103219202, new Number(410321920, 2)]
+            ["410321-9202", new Number('410321920', 2)],
+            [4103219202, new Number('410321920', 2)],
+            ['89148000003974165685', new Number('8914800000397416568', 5)],
+            ['abc123', new Number('12', 3)],
+            // Use any number that is larger then PHP_INT_MAX.
+            [((string) PHP_INT_MAX).'21', new Number(((string) PHP_INT_MAX).'2', 1)],
+        ];
+    }
+
+    /**
+     * @dataProvider provideFromString_fail
+     */
+    public function testFromString_fail($number, $checkDigit, $expected)
+    {
+        $this->expectException($expected);
+        new Number($number, $checkDigit);
+    }
+
+    public function provideFromString_fail()
+    {
+        return [
+            ['', 1, \InvalidArgumentException::class],
+            ['xyz ', null, \InvalidArgumentException::class],
         ];
     }
 
@@ -60,4 +81,21 @@ public function provideToString_success()
             [new Number(12345, 5), "123455"]
         ];
     }
+
+    /**
+     * @dataProvider provideNew_fail
+     */
+    public function testNew_fail($number, $checkDigit, $expected)
+    {
+        $this->expectException($expected);
+        new Number($number, $checkDigit);
+    }
+
+    public function provideNew_fail()
+    {
+        return [
+            ['abc123', 1, \InvalidArgumentException::class],
+            ['123 ', null, \InvalidArgumentException::class],
+        ];
+    }
 }