Added new tests

Author: le0daniel

src/Utility/Strings.php

@@ -14,9 +14,16 @@ final class Strings
      */
     public static function splitAtIndex(string $string, int $index): array
     {
+        if ($index < 0) {
+            throw new \Exception('Can not spilt a string at a negative index.');
+        }
+
         return [
             substr($string, 0, $index),
-            $part2 = substr($string, $index),
+            $index < strlen($string)
+                ? substr($string, $index)
+                : ''
+            ,
         ];
     }
 

tests/Utility/SignaturesTest.php

@@ -0,0 +1,49 @@
+<?php
+
+namespace le0daniel\Tests\Laravel\ImageEngine\Utility;
+
+use le0daniel\Laravel\ImageEngine\Utility\SignatureException;
+use le0daniel\Laravel\ImageEngine\Utility\Signatures;
+use PHPUnit\Framework\TestCase;
+
+final class SignaturesTest extends TestCase
+{
+    private const SECRET = 'asdfasdf!_';
+
+    public function testSign()
+    {
+        $this->assertSame(
+            'the-string::PT7sqFr2CdpljWjc5HCbLevrooH_xT1D-WDnLBEBqzI',
+            Signatures::sign(self::SECRET, 'the-string')
+        );
+    }
+
+    public function testVerifyAndReturnPayloadString()
+    {
+        $this->assertEquals(
+            'the-string',
+            Signatures::verifyAndReturnPayloadString(
+                self::SECRET,
+                'the-string::PT7sqFr2CdpljWjc5HCbLevrooH_xT1D-WDnLBEBqzI'
+            )
+        );
+    }
+
+    public function testVerifyAndReturnPayloadStringWithInvalidStructure()
+    {
+        $this->expectException(SignatureException::class);
+        $this->expectExceptionMessage('The signed string is of invalid structure');
+        Signatures::verifyAndReturnPayloadString(self::SECRET, 'asdadasd');
+
+        $this->fail('Should not reach this.');
+    }
+
+    public function testVerifyAndReturnPayloadStringWithTamperedString()
+    {
+        $this->expectException(SignatureException::class);
+        $this->expectExceptionMessage('Signature mismatches.');
+        Signatures::verifyAndReturnPayloadString(self::SECRET, 'asdadasd::ajbflenfiwenfiwef');
+
+        $this->fail('Should not reach this.');
+    }
+}

tests/Utility/StringsTest.php

@@ -0,0 +1,27 @@
+<?php
+
+namespace le0daniel\Tests\Laravel\ImageEngine\Utility;
+
+use le0daniel\Laravel\ImageEngine\Utility\Strings;
+use PHPUnit\Framework\TestCase;
+
+final class StringsTest extends TestCase
+{
+
+    public function testSplitAtIndex()
+    {
+        $this->assertEquals(['test', '-string'], Strings::splitAtIndex('test-string', 4));
+        $this->assertEquals(['', 'test-string'], Strings::splitAtIndex('test-string', 0));
+        $this->assertEquals(['test-string', ''], Strings::splitAtIndex('test-string', 100));
+
+        $this->assertEquals(['test-strin', 'g'], Strings::splitAtIndex('test-string', 10));
+        $this->assertEquals(['test-string', ''], Strings::splitAtIndex('test-string', 11));
+        $this->assertEquals(['test-string', ''], Strings::splitAtIndex('test-string', 12));
+
+        $this->expectException(\Exception::class);
+        $this->expectExceptionMessage('Can not spilt a string at a negative index.');
+        Strings::splitAtIndex('test-string', -1);
+
+        $this->fail('Should not reach this.');
+    }
+}