Updated composer.json and PHPUnit

Updating the PHP version constraint and PHPUnit allows the library to be installed under PHP 8 now

.gitignore

@@ -1,3 +1,4 @@
 /composer.lock
 /vendor
 .idea/
+.phpunit.result.cache

composer.json

@@ -18,10 +18,10 @@
     }
   ],
   "require": {
-    "php": "^5.6|^7.0"
+    "php": ">=5.6"
   },
   "require-dev": {
-    "phpunit/phpunit": "^5.7"
+    "phpunit/phpunit": "^9.0"
   },
   "autoload": {
     "psr-4": {

phpunit.xml.dist

@@ -1,10 +1,13 @@
-<phpunit bootstrap="tests/bootstrap.php">
-    <testsuite>
-        <directory suffix="Test.php">tests</directory>
-    </testsuite>
-    <filter>
-        <whitelist processUncoveredFilesFromWhitelist="true">
-            <directory suffix=".php">src</directory>
-        </whitelist>
-    </filter>
+<?xml version="1.0" encoding="UTF-8"?>
+<phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" bootstrap="vendor/autoload.php" backupGlobals="false" backupStaticAttributes="false" colors="true" verbose="true" convertErrorsToExceptions="true" convertNoticesToExceptions="true" convertWarningsToExceptions="true" processIsolation="false" stopOnFailure="false" xsi:noNamespaceSchemaLocation="https://schema.phpunit.de/9.3/phpunit.xsd">
+    <coverage>
+        <include>
+            <directory suffix=".php">tests/</directory>
+        </include>
+    </coverage>
+    <testsuites>
+        <testsuite name="Tests">
+            <directory>tests</directory>
+        </testsuite>
+    </testsuites>
 </phpunit>

tests/QrReaderTest.php

@@ -2,16 +2,17 @@
 
 namespace Khanamiryan\QrCodeTests;
 
+use PHPUnit\Framework\TestCase;
 use Zxing\QrReader;
 
-class QrReaderTest extends \PHPUnit\Framework\TestCase
+class QrReaderTest extends TestCase
 {
 
     public function testText1()
     {
         $image = __DIR__ . "/qrcodes/hello_world.png";
 
         $qrcode = new QrReader($image);
-        $this->assertSame("Hello world!", $qrcode->text());
+        self::assertSame("Hello world!", $qrcode->text());
     }
 }