Constants/RestrictedConstants: minor efficiency fix

This commit introduces `private` property versions of the pre-existing `public` properties, where the array format is different.
The `private` properties have the target constant names as the array key, not as the value.

This allows for using `isset()` instead of `in_array()`.

Author: jrfnl

WordPressVIPMinimum/Sniffs/Constants/RestrictedConstantsSniff.php

@@ -36,12 +36,39 @@ class RestrictedConstantsSniff extends Sniff {
 		'WP_CRON_CONTROL_SECRET',
 	];
 
+	/**
+	 * List of (global) constant names, which should not be referenced in userland code, nor (re-)declared.
+	 *
+	 * {@internal The `public` versions of these properties can't be removed until the next major,
+	 * though a decision is still needed whether they should be removed at all.
+	 * Also see: Automattic/VIP-Coding-Standards#234 for more context and discussion about this.}
+	 *
+	 * @var array<string, int> Key is the constant name, value is irrelevant.
+	 */
+	private $restrictedConstants = [];
+
+	/**
+	 * List of (global) constants, which should not be (re-)declared, but may be referenced.
+	 *
+	 * {@internal The `public` versions of these properties can't be removed until the next major,
+	 * though a decision is still needed whether they should be removed at all.
+	 * Also see: Automattic/VIP-Coding-Standards#234 for more context and discussion about this.}
+	 *
+	 * @var array<string, int> Key is the constant name, value is irrelevant.
+	 */
+	private $restrictedRedeclaration = [];
+
 	/**
 	 * Returns an array of tokens this test wants to listen for.
 	 *
 	 * @return array<int|string>
 	 */
 	public function register() {
+		// For now, set the `private` properties based on the values of the `public` properties.
+		// This should be revisited when Automattic/VIP-Coding-Standards#234 gets actioned.
+		$this->restrictedConstants     = array_flip($this->restrictedConstantNames);
+		$this->restrictedRedeclaration = array_flip($this->restrictedConstantDeclaration);
+
 		return [
 			T_CONSTANT_ENCAPSED_STRING,
 			T_STRING,
@@ -63,12 +90,14 @@ public function process_token( $stackPtr ) {
 			$constantName = trim( $this->tokens[ $stackPtr ]['content'], "\"'" );
 		}
 
-		if ( in_array( $constantName, $this->restrictedConstantNames, true ) === false && in_array( $constantName, $this->restrictedConstantDeclaration, true ) === false ) {
+		if ( isset( $this->restrictedConstants[ $constantName ] ) === false
+			&& isset( $this->restrictedRedeclaration[ $constantName ] ) === false
+		) {
 			// Not the constant we are looking for.
 			return;
 		}
 
-		if ( $this->tokens[ $stackPtr ]['code'] === T_STRING && in_array( $constantName, $this->restrictedConstantNames, true ) === true ) {
+		if ( $this->tokens[ $stackPtr ]['code'] === T_STRING && isset( $this->restrictedConstants[ $constantName ] ) === true ) {
 			$message = 'Code is touching the `%s` constant. Make sure it\'s used appropriately.';
 			$data    = [ $constantName ];
 			$this->phpcsFile->addWarning( $message, $stackPtr, 'UsingRestrictedConstant', $data );
@@ -102,7 +131,7 @@ public function process_token( $stackPtr ) {
 			if ( $this->tokens[ $previous ]['content'] === 'define' ) {
 				$message = 'The definition of `%s` constant is prohibited. Please use a different name.';
 				$this->phpcsFile->addError( $message, $previous, 'DefiningRestrictedConstant', $data );
-			} elseif ( in_array( $constantName, $this->restrictedConstantNames, true ) === true ) {
+			} elseif ( isset( $this->restrictedConstants[ $constantName ] ) === true ) {
 				$message = 'Code is touching the `%s` constant. Make sure it\'s used appropriately.';
 				$this->phpcsFile->addWarning( $message, $previous, 'UsingRestrictedConstant', $data );
 			}