WPThemeReview/Sniffs/CoreFunctionality/NoFaviconSniff.php
public function process( File $phpcsFile, $stackPtr ) {

		$tokens = $phpcsFile->getTokens();
		$token  = $tokens[ $stackPtr ];

		if ( preg_match( $this->favicon_regex, $token['content'] ) > 0 ) {
			$phpcsFile->addError(
				'Code for favicon found. Favicons are handled by the "Site Icon" setting in the customizer since WP version 4.3.',
				$stackPtr,
				'NoFavicon'
			);
		}
	}
public function process( File $phpcsFile, $stackPtr ) {

		$tokens = $phpcsFile->getTokens();
		$token  = $tokens[ $stackPtr ];

		if ( preg_match( $this->favicon_regex, $token['content'] ) > 0 ) {
			$phpcsFile->addError(
				'Code for favicon found. Favicons are handled by the "Site Icon" setting in the customizer since WP version 4.3.',
				$stackPtr,
				'NoFavicon'
			);
		}
	}
Processes this test, when one of its tokens is encountered.

@param \PHP_CodeSniffer\Files\File $phpcsFile The PHP_CodeSniffer file where the
token was found.
@param int                         $stackPtr  The position of the current token
in the stack.

@return void