Introducing coding standards validation.

vendor/wp-coding-standards/wpcs/WordPress/Sniffs/VIP/SessionVariableUsageSniff.php

@@ -0,0 +1,81 @@
+<?php
+/**
+ * WordPress Coding Standard.
+ *
+ * @package WPCS\WordPressCodingStandards
+ * @link    https://github.com/WordPress-Coding-Standards/WordPress-Coding-Standards
+ * @license https://opensource.org/licenses/MIT MIT
+ */
+
+namespace WordPress\Sniffs\VIP;
+
+use WordPress\Sniff;
+
+/**
+ * Discourages the use of the session variable.
+ * Creating a session writes a file to the server and is unreliable in a multi-server environment.
+ *
+ * @link https://lobby.vip.wordpress.com/wordpress-com-documentation/code-review-what-we-look-for/#session-start-and-other-session-functions
+ *
+ * @package WPCS\WordPressCodingStandards
+ *
+ * @since   0.3.0
+ * @since   0.10.0 The sniff no longer needlessly extends the Generic_Sniffs_PHP_ForbiddenFunctionsSniff
+ *                 which it didn't use.
+ * @since   0.12.0 This class now extends WordPress_Sniff.
+ * @since   0.13.0 Class name changed: this class is now namespaced.
+ *
+ * @deprecated 1.0.0  This sniff has been deprecated.
+ *                    This file remains for now to prevent BC breaks.
+ */
+class SessionVariableUsageSniff extends Sniff {
+
+	/**
+	 * Keep track of whether the warnings have been thrown to prevent
+	 * the messages being thrown for every token triggering the sniff.
+	 *
+	 * @since 1.0.0
+	 *
+	 * @var array
+	 */
+	private $thrown = array(
+		'DeprecatedSniff' => false,
+	);
+
+	/**
+	 * Returns an array of tokens this test wants to listen for.
+	 *
+	 * @return array
+	 */
+	public function register() {
+		return array(
+			\T_VARIABLE,
+		);
+	}
+
+	/**
+	 * Process the token and handle the deprecation notice.
+	 *
+	 * @param int $stackPtr The position of the current token in the stack.
+	 *
+	 * @return void
+	 */
+	public function process_token( $stackPtr ) {
+		if ( false === $this->thrown['DeprecatedSniff'] ) {
+			$this->thrown['DeprecatedSniff'] = $this->phpcsFile->addWarning(
+				'The "WordPress.VIP.SessionVariableUsage" sniff has been deprecated. Please update your custom ruleset.',
+				0,
+				'DeprecatedSniff'
+			);
+		}
+
+		if ( '$_SESSION' === $this->tokens[ $stackPtr ]['content'] ) {
+			$this->phpcsFile->addError(
+				'Usage of $_SESSION variable is prohibited.',
+				$stackPtr,
+				'SessionVarsProhibited'
+			);
+		}
+	}
+
+}