import static test ruleset

Magento2/Sniffs/Namespaces/UseDeclarationSniff.php

@@ -0,0 +1,51 @@
+<?php
+/**
+ * Copyright © Magento. All rights reserved.
+ * See COPYING.txt for license details.
+ */
+namespace Magento2\Sniffs\Namespaces;
+
+use PHP_CodeSniffer\Sniffs\Sniff;
+use PHP_CodeSniffer\Files\File;
+
+/**
+ * Detects static test namespace.
+ */
+class UseDeclarationSniff implements Sniff
+{
+
+    /**
+     * @var string
+     */
+    private $_prohibitNamespace = 'Magento\Tests';
+
+    /**
+     * @var string
+     */
+    protected $warningMessage = 'Incorrect namespace has been imported.';
+
+    /**
+     * @var string
+     */
+    protected $warningCode = 'WrongImportNamespaces';
+
+    /**
+     * @inheritdoc
+     */
+    public function register()
+    {
+        return [T_USE];
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function process(File $phpcsFile, $stackPtr)
+    {
+        $next = $phpcsFile->findNext([T_COMMA, T_SEMICOLON, T_OPEN_USE_GROUP, T_CLOSE_TAG], ($stackPtr + 1));
+        $getTokenAsContent = $phpcsFile->getTokensAsString($stackPtr, ($next - $stackPtr));
+        if (strpos($getTokenAsContent, $this->_prohibitNamespace) !== false) {
+            $phpcsFile->addWarning($this->warningMessage, $stackPtr, $this->warningCode);
+        }
+    }
+}

Magento2/Tests/Namespaces/UseDeclarationUnitTest.inc

@@ -0,0 +1,4 @@
+<?php
+use Magento\Tests;
+use Magento\Foo\Tests as FakeTest;
+use Magento\Real\Classes;

Magento2/Tests/Namespaces/UseDeclarationUnitTest.php

@@ -0,0 +1,30 @@
+<?php
+/**
+ * Copyright © Magento. All rights reserved.
+ * See COPYING.txt for license details.
+ */
+namespace Magento2\Tests\Namespaces;
+
+use PHP_CodeSniffer\Tests\Standards\AbstractSniffUnitTest;
+
+/**
+ * Class InterfaceNameUnitTest
+ */
+class UseDeclarationUnitTest extends AbstractSniffUnitTest
+{
+    /**
+     * @inheritdoc
+     */
+    public function getErrorList()
+    {
+        return [];
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function getWarningList()
+    {
+        return [2 => 1];
+    }
+}

Magento2/ruleset.xml

@@ -189,6 +189,10 @@
         <exclude-pattern>*Test.php</exclude-pattern>
         <exclude-pattern>*/tests/*</exclude-pattern>
     </rule>
+    <rule ref="Magento2.Namespaces.UseDeclaration">
+        <severity>8</severity>
+        <type>warning</type>
+    </rule>
     <rule ref="Magento2.NamingConvention.InterfaceName">
         <severity>8</severity>
         <type>warning</type>