Update Integration Test Memory helper coding style and unit tests

Author: ishakhsuvarov

dev/tests/integration/framework/Magento/TestFramework/Helper/Memory.php

@@ -10,6 +10,9 @@
  */
 namespace Magento\TestFramework\Helper;
 
+/**
+ * Integration Test Framework memory management logic.
+ */
 class Memory
 {
     /**
@@ -38,9 +41,9 @@ public function __construct(\Magento\Framework\Shell $shell)
     /**
      * Retrieve the effective memory usage of the current process
      *
-     * memory_get_usage() cannot be used because of the bug
-     * @link https://bugs.php.net/bug.php?id=62467
+     * Function memory_get_usage() cannot be used because of the bug
      *
+     * @link https://bugs.php.net/bug.php?id=62467
      * @return int Memory usage in bytes
      */
     public function getRealMemoryUsage()
@@ -100,6 +103,7 @@ protected function _getWinProcessMemoryUsage($pid)
      * @return int
      * @throws \InvalidArgumentException
      * @throws \OutOfBoundsException
+     * phpcs:ignore Magento2.Functions.StaticFunction
      */
     public static function convertToBytes($number)
     {
@@ -132,9 +136,10 @@ public static function convertToBytes($number)
      * - but the value has only one delimiter, such as "234,56", then it is impossible to know whether it is decimal
      *   separator or not. Only knowing the right format would allow this.
      *
-     * @param $number
+     * @param string $number
      * @return string
      * @throws \InvalidArgumentException
+     * phpcs:ignore Magento2.Functions.StaticFunction
      */
     protected static function _convertToNumber($number)
     {
@@ -152,6 +157,7 @@ protected static function _convertToNumber($number)
      *
      * @link http://php.net/manual/en/function.php-uname.php
      * @return boolean
+     * phpcs:ignore Magento2.Functions.StaticFunction
      */
     public static function isMacOs()
     {

dev/tests/integration/framework/tests/unit/testsuite/Magento/Test/Helper/MemoryTest.php

@@ -21,16 +21,7 @@ public function testGetRealMemoryUsageUnix()
     {
         $object = new \Magento\TestFramework\Helper\Memory($this->_shell);
         $this->_shell->expects(
-            $this->at(0)
-        )->method(
-            'execute'
-        )->with(
-            $this->stringStartsWith('tasklist.exe ')
-        )->will(
-            $this->throwException(new \Magento\Framework\Exception\LocalizedException(__('command not found')))
-        );
-        $this->_shell->expects(
-            $this->at(1)
+            $this->once()
         )->method(
             'execute'
         )->with(
@@ -44,7 +35,16 @@ public function testGetRealMemoryUsageUnix()
     public function testGetRealMemoryUsageWin()
     {
         $this->_shell->expects(
-            $this->once()
+            $this->at(0)
+        )->method(
+            'execute'
+        )->with(
+            $this->stringStartsWith('ps ')
+        )->will(
+            $this->throwException(new \Magento\Framework\Exception\LocalizedException(__('command not found')))
+        );
+        $this->_shell->expects(
+            $this->at(1)
         )->method(
             'execute'
         )->with(