diff --git a/tests/methods/ParseTest.php b/tests/methods/ParseTest.php
index fb514ea..ef1514d 100644
--- a/tests/methods/ParseTest.php
+++ b/tests/methods/ParseTest.php
@@ -326,7 +326,7 @@ public function testAutoQuotes($file, $enclosure) {
      * @return mixed Method return.
      */
     private function invokeMethod($object, $methodName, $parameters = []) {
-        $reflection = new ReflectionClass(get_class($object));
+        $reflection = new ReflectionClass($object::class);
         $method = $reflection->getMethod($methodName);
         $method->setAccessible(true);
 
diff --git a/tests/methods/SaveTest.php b/tests/methods/SaveTest.php
index 23025e0..10a93b3 100644
--- a/tests/methods/SaveTest.php
+++ b/tests/methods/SaveTest.php
@@ -51,7 +51,7 @@ public function testSaveWithUnixLineEnding() {
 
     public function testSaveWithNewHeader() {
         $this->csv->linefeed = "\n";
-        $this->csv->titles = array("NewTitle");
+        $this->csv->titles = ["NewTitle"];
         $expected = "NewTitle\n0444\n5555\n";
         $this->saveAndCompare($expected);
     }
diff --git a/tests/methods/UnparseTest.php b/tests/methods/UnparseTest.php
index 4f414cc..60448dd 100644
--- a/tests/methods/UnparseTest.php
+++ b/tests/methods/UnparseTest.php
@@ -20,7 +20,7 @@ protected function setUp(): void {
     }
 
     public function testUnparseWithParameters() {
-        $fields = array('a' => 'AA', 'b' => 'BB');
+        $fields = ['a' => 'AA', 'b' => 'BB'];
         $data = [['a' => 'value1', 'b' => 'value2']];
         $csv_object = new Csv();
         $csv_string = $csv_object->unparse($data, $fields);
@@ -52,24 +52,21 @@ public function testUnparseDefaultWithoutHeading() {
 
     public function testUnparseRenameFields() {
         $expected = "C1,C2\rvalue1,value2\rvalue3,value4\r";
-        $this->unparseAndCompare($expected, array("C1", "C2"));
+        $this->unparseAndCompare($expected, ["C1", "C2"]);
     }
 
     public function testReorderFields() {
         $expected = "column2,column1\rvalue2,value1\rvalue4,value3\r";
-        $this->unparseAndCompare($expected, array("column2", "column1"));
+        $this->unparseAndCompare($expected, ["column2", "column1"]);
     }
 
     public function testSubsetFields() {
         $expected = "column1\rvalue1\rvalue3\r";
-        $this->unparseAndCompare($expected, array("column1"));
+        $this->unparseAndCompare($expected, ["column1"]);
     }
 
     public function testReorderAndRenameFields() {
-        $fields = array(
-            'column2' => 'C2',
-            'column1' => 'C1',
-        );
+        $fields = ['column2' => 'C2', 'column1' => 'C1'];
         $expected = "C2,C1\rvalue2,value1\rvalue4,value3\r";
         $this->unparseAndCompare($expected, $fields);
     }
@@ -99,7 +96,7 @@ public function testObjectCells() {
         $this->unparseAndCompare($expected);
     }
 
-    private function unparseAndCompare($expected, $fields = array()) {
+    private function unparseAndCompare($expected, $fields = []) {
         $str = $this->csv->unparse($this->csv->data, $fields);
         $this->assertEquals($expected, $str);
     }