Source for file ComparisonOperatorUsageSniff.php

<?php
/**
 * A Sniff to enforce the use of IDENTICAL type operators rather than EQUAL operators.
 *
 * @author    Greg Sherwood <gsherwood@squiz.net>
 * @copyright 2006-2015 Squiz Pty Ltd (ABN 77 084 670 600)
 * @license   https://github.com/squizlabs/PHP_CodeSniffer/blob/master/licence.txt BSD Licence
 */
 
namespace PHP_CodeSniffer\Standards\Squiz\Sniffs\Operators;
 
use PHP_CodeSniffer\Sniffs\Sniff;
use PHP_CodeSniffer\Files\File;
use PHP_CodeSniffer\Util\Tokens;
 
class ComparisonOperatorUsageSniff implements Sniff
{
 
    /**
     * A list of tokenizers this sniff supports.
     *
     * @var array 
     */
    public $supportedTokenizers = array(
                                   'PHP',
                                   'JS',
                                  );
 
    /**
     * A list of valid comparison operators.
     *
     * @var array 
     */
    private static $validOps = array(
                                T_IS_IDENTICAL,
                                T_IS_NOT_IDENTICAL,
                                T_LESS_THAN,
                                T_GREATER_THAN,
                                T_IS_GREATER_OR_EQUAL,
                                T_IS_SMALLER_OR_EQUAL,
                                T_INSTANCEOF,
                               );
 
    /**
     * A list of invalid operators with their alternatives.
     *
     * @var array<int, string>
     */
    private static $invalidOps = array(
                                  'PHP' => array(
                                            T_IS_EQUAL     => '===',
                                            T_IS_NOT_EQUAL => '!==',
                                            T_BOOLEAN_NOT  => '=== FALSE',
                                           ),
                                  'JS'  => array(
                                            T_IS_EQUAL     => '===',
                                            T_IS_NOT_EQUAL => '!==',
                                           ),
                                 );
 
 
    /**
     * Registers the token types that this sniff wishes to listen to.
     *
     * @return array 
     */
    public function register()
    {
        return array(
                T_IF,
                T_ELSEIF,
                T_INLINE_THEN,
                T_WHILE,
                T_FOR,
               );
 
    }//end register()
 
 
    /**
     * Process the tokens that this sniff is listening for.
     *
     * @param \PHP_CodeSniffer\Files\File $phpcsFile The file where the token was found.
     * @param int                         $stackPtr  The position in the stack where the token
     *                                                was found.
     *
     * @return void 
     */
    public function process(File $phpcsFile, $stackPtr)
    {
        $tokens    = $phpcsFile->getTokens();
        $tokenizer = $phpcsFile->tokenizerType;
 
        if ($tokens[$stackPtr]['code'] === T_INLINE_THEN) {
            $end = $phpcsFile->findPrevious(Tokens::$emptyTokens, ($stackPtr - 1), null, true);
            if ($tokens[$end]['code'] !== T_CLOSE_PARENTHESIS) {
                // This inline IF statement does not have its condition
                // bracketed, so we need to guess where it starts.
                for ($i = ($end - 1); $i >= 0; $i--) {
                    if ($tokens[$i]['code'] === T_SEMICOLON) {
                        // Stop here as we assume it is the end
                        // of the previous statement.
                        break;
                    } else if ($tokens[$i]['code'] === T_OPEN_TAG) {
                        // Stop here as this is the start of the file.
                        break;
                    } else if ($tokens[$i]['code'] === T_CLOSE_CURLY_BRACKET) {
                        // Stop if this is the closing brace of
                        // a code block.
                        if (isset($tokens[$i]['scope_opener']) === true) {
                            break;
                        }
                    } else if ($tokens[$i]['code'] === T_OPEN_CURLY_BRACKET) {
                        // Stop if this is the opening brace of
                        // a code block.
                        if (isset($tokens[$i]['scope_closer']) === true) {
                            break;
                        }
                    }
                }//end for
 
                $start = $phpcsFile->findNext(Tokens::$emptyTokens, ($i + 1), null, true);
            } else {
                if (isset($tokens[$end]['parenthesis_opener']) === false) {
                    return;
                }
 
                $start = $tokens[$end]['parenthesis_opener'];
            }//end if
        } else if ($tokens[$stackPtr]['code'] === T_FOR) {
            if (isset($tokens[$stackPtr]['parenthesis_opener']) === false) {
                return;
            }
 
            $openingBracket = $tokens[$stackPtr]['parenthesis_opener'];
            $closingBracket = $tokens[$stackPtr]['parenthesis_closer'];
 
            $start = $phpcsFile->findNext(T_SEMICOLON, $openingBracket, $closingBracket);
            $end   = $phpcsFile->findNext(T_SEMICOLON, ($start + 1), $closingBracket);
            if ($start === false || $end === false) {
                return;
            }
        } else {
            if (isset($tokens[$stackPtr]['parenthesis_opener']) === false) {
                return;
            }
 
            $start = $tokens[$stackPtr]['parenthesis_opener'];
            $end   = $tokens[$stackPtr]['parenthesis_closer'];
        }//end if
 
        $requiredOps = 0;
        $foundOps    = 0;
        $foundBools  = 0;
 
        for ($i = $start; $i <= $end; $i++) {
            $type = $tokens[$i]['code'];
            if (in_array($type, array_keys(self::$invalidOps[$tokenizer])) === true) {
                $error = 'Operator %s prohibited; use %s instead';
                $data  = array(
                          $tokens[$i]['content'],
                          self::$invalidOps[$tokenizer][$type],
                         );
                $phpcsFile->addError($error, $i, 'NotAllowed', $data);
                $foundOps++;
            } else if (in_array($type, self::$validOps) === true) {
                $foundOps++;
            }
 
            if ($tokens[$i]['code'] === T_TRUE || $tokens[$i]['code'] === T_FALSE) {
                $foundBools++;
            }
 
            if ($phpcsFile->tokenizerType !== 'JS'
                && ($tokens[$i]['code'] === T_BOOLEAN_AND
                || $tokens[$i]['code'] === T_BOOLEAN_OR)
            ) {
                $requiredOps++;
 
                // When the instanceof operator is used with another operator
                // like ===, you can get more ops than are required.
                if ($foundOps > $requiredOps) {
                    $foundOps = $requiredOps;
                }
 
                // If we get to here and we have not found the right number of
                // comparison operators, then we must have had an implicit
                // true operation i.e., if ($a) instead of the required
                // if ($a === true), so let's add an error.
                if ($requiredOps !== $foundOps) {
                    $error = 'Implicit true comparisons prohibited; use === TRUE instead';
                    $phpcsFile->addError($error, $stackPtr, 'ImplicitTrue');
                    $foundOps++;
                }
            }
        }//end for
 
        $requiredOps++;
 
        if ($phpcsFile->tokenizerType !== 'JS'
            && $foundOps < $requiredOps
            && ($requiredOps !== $foundBools)
        ) {
            $error = 'Implicit true comparisons prohibited; use === TRUE instead';
            $phpcsFile->addError($error, $stackPtr, 'ImplicitTrue');
        }
 
    }//end process()
 
 
}//end class