OperatorBracketSniff.php

<?php


/**
 * Tests that all arithmetic operations are bracketed.
 *
 * @author    Greg Sherwood <gsherwood@squiz.net>
 * @copyright 2006-2015 Squiz Pty Ltd (ABN 77 084 670 600)
 * @license   https://github.com/PHPCSStandards/PHP_CodeSniffer/blob/master/licence.txt BSD Licence
 */
namespace PHP_CodeSniffer\Standards\Squiz\Sniffs\Formatting;

use PHP_CodeSniffer\Files\File;
use PHP_CodeSniffer\Sniffs\Sniff;
use PHP_CodeSniffer\Util\Tokens;
class OperatorBracketSniff implements Sniff {
    
    /**
     * A list of tokenizers this sniff supports.
     *
     * @var array
     */
    public $supportedTokenizers = [
        'PHP',
        'JS',
    ];
    
    /**
     * Returns an array of tokens this test wants to listen for.
     *
     * @return array<int|string>
     */
    public function register() {
        return Tokens::$operators;
    }
    
    //end register()
    
    /**
     * Processes this test, when one of its tokens is encountered.
     *
     * @param \PHP_CodeSniffer\Files\File $phpcsFile The file being scanned.
     * @param int                         $stackPtr  The position of the current token in the
     *                                               stack passed in $tokens.
     *
     * @return void
     */
    public function process(File $phpcsFile, $stackPtr) {
        $tokens = $phpcsFile->getTokens();
        if ($phpcsFile->tokenizerType === 'JS' && $tokens[$stackPtr]['code'] === T_PLUS) {
            // JavaScript uses the plus operator for string concatenation as well
            // so we cannot accurately determine if it is a string concat or addition.
            // So just ignore it.
            return;
        }
        // If the & is a reference, then we don't want to check for brackets.
        if ($tokens[$stackPtr]['code'] === T_BITWISE_AND && $phpcsFile->isReference($stackPtr) === true) {
            return;
        }
        // There is one instance where brackets aren't needed, which involves
        // the minus sign being used to assign a negative number to a variable.
        if ($tokens[$stackPtr]['code'] === T_MINUS) {
            // Check to see if we are trying to return -n.
            $prev = $phpcsFile->findPrevious(Tokens::$emptyTokens, $stackPtr - 1, null, true);
            if ($tokens[$prev]['code'] === T_RETURN) {
                return;
            }
            $number = $phpcsFile->findNext(T_WHITESPACE, $stackPtr + 1, null, true);
            if ($tokens[$number]['code'] === T_LNUMBER || $tokens[$number]['code'] === T_DNUMBER) {
                $previous = $phpcsFile->findPrevious(T_WHITESPACE, $stackPtr - 1, null, true);
                if ($previous !== false) {
                    $isAssignment = isset(Tokens::$assignmentTokens[$tokens[$previous]['code']]);
                    $isEquality = isset(Tokens::$equalityTokens[$tokens[$previous]['code']]);
                    $isComparison = isset(Tokens::$comparisonTokens[$tokens[$previous]['code']]);
                    $isUnary = isset(Tokens::$operators[$tokens[$previous]['code']]);
                    if ($isAssignment === true || $isEquality === true || $isComparison === true || $isUnary === true) {
                        // This is a negative assignment or comparison.
                        // We need to check that the minus and the number are
                        // adjacent.
                        if ($number - $stackPtr !== 1) {
                            $error = 'No space allowed between minus sign and number';
                            $phpcsFile->addError($error, $stackPtr, 'SpacingAfterMinus');
                        }
                        return;
                    }
                }
            }
        }
        
        //end if
        $previousToken = $phpcsFile->findPrevious(T_WHITESPACE, $stackPtr - 1, null, true, null, true);
        if ($previousToken !== false) {
            // A list of tokens that indicate that the token is not
            // part of an arithmetic operation.
            $invalidTokens = [
                T_COMMA => true,
                T_COLON => true,
                T_OPEN_PARENTHESIS => true,
                T_OPEN_SQUARE_BRACKET => true,
                T_OPEN_CURLY_BRACKET => true,
                T_OPEN_SHORT_ARRAY => true,
                T_CASE => true,
                T_EXIT => true,
                T_MATCH_ARROW => true,
            ];
            if (isset($invalidTokens[$tokens[$previousToken]['code']]) === true) {
                return;
            }
        }
        if ($tokens[$stackPtr]['code'] === T_BITWISE_OR && isset($tokens[$stackPtr]['nested_parenthesis']) === true) {
            $brackets = $tokens[$stackPtr]['nested_parenthesis'];
            $lastBracket = array_pop($brackets);
            if (isset($tokens[$lastBracket]['parenthesis_owner']) === true && $tokens[$tokens[$lastBracket]['parenthesis_owner']]['code'] === T_CATCH) {
                // This is a pipe character inside a catch statement, so it is acting
                // as an exception type separator and not an arithmetic operation.
                return;
            }
        }
        // Tokens that are allowed inside a bracketed operation.
        $allowed = [
            T_VARIABLE,
            T_LNUMBER,
            T_DNUMBER,
            T_STRING,
            T_WHITESPACE,
            T_NS_SEPARATOR,
            T_THIS,
            T_SELF,
            T_STATIC,
            T_PARENT,
            T_OBJECT_OPERATOR,
            T_NULLSAFE_OBJECT_OPERATOR,
            T_DOUBLE_COLON,
            T_OPEN_SQUARE_BRACKET,
            T_CLOSE_SQUARE_BRACKET,
            T_MODULUS,
            T_NONE,
            T_BITWISE_NOT,
        ];
        $allowed += Tokens::$operators;
        $lastBracket = false;
        if (isset($tokens[$stackPtr]['nested_parenthesis']) === true) {
            $parenthesis = array_reverse($tokens[$stackPtr]['nested_parenthesis'], true);
            foreach ($parenthesis as $bracket => $endBracket) {
                $prevToken = $phpcsFile->findPrevious(T_WHITESPACE, $bracket - 1, null, true);
                $prevCode = $tokens[$prevToken]['code'];
                if ($prevCode === T_ISSET) {
                    // This operation is inside an isset() call, but has
                    // no bracket of it's own.
                    break;
                }
                if ($prevCode === T_STRING || $prevCode === T_SWITCH || $prevCode === T_MATCH) {
                    // We allow simple operations to not be bracketed.
                    // For example, ceil($one / $two).
                    for ($prev = $stackPtr - 1; $prev > $bracket; $prev--) {
                        if (in_array($tokens[$prev]['code'], $allowed, true) === true) {
                            continue;
                        }
                        if ($tokens[$prev]['code'] === T_CLOSE_PARENTHESIS) {
                            $prev = $tokens[$prev]['parenthesis_opener'];
                        }
                        else {
                            break;
                        }
                    }
                    if ($prev !== $bracket) {
                        break;
                    }
                    for ($next = $stackPtr + 1; $next < $endBracket; $next++) {
                        if (in_array($tokens[$next]['code'], $allowed, true) === true) {
                            continue;
                        }
                        if ($tokens[$next]['code'] === T_OPEN_PARENTHESIS) {
                            $next = $tokens[$next]['parenthesis_closer'];
                        }
                        else {
                            break;
                        }
                    }
                    if ($next !== $endBracket) {
                        break;
                    }
                }
                
                //end if
                if (in_array($prevCode, Tokens::$scopeOpeners, true) === true) {
                    // This operation is inside a control structure like FOREACH
                    // or IF, but has no bracket of it's own.
                    // The only control structures allowed to do this are SWITCH and MATCH.
                    if ($prevCode !== T_SWITCH && $prevCode !== T_MATCH) {
                        break;
                    }
                }
                if ($prevCode === T_OPEN_PARENTHESIS) {
                    // These are two open parenthesis in a row. If the current
                    // one doesn't enclose the operator, go to the previous one.
                    if ($endBracket < $stackPtr) {
                        continue;
                    }
                }
                $lastBracket = $bracket;
                break;
            }
            
            //end foreach
        }
        
        //end if
        if ($lastBracket === false) {
            // It is not in a bracketed statement at all.
            $this->addMissingBracketsError($phpcsFile, $stackPtr);
            return;
        }
        else {
            if ($tokens[$lastBracket]['parenthesis_closer'] < $stackPtr) {
                // There are a set of brackets in front of it that don't include it.
                $this->addMissingBracketsError($phpcsFile, $stackPtr);
                return;
            }
            else {
                // We are enclosed in a set of bracket, so the last thing to
                // check is that we are not also enclosed in square brackets
                // like this: ($array[$index + 1]), which is invalid.
                $brackets = [
                    T_OPEN_SQUARE_BRACKET,
                    T_CLOSE_SQUARE_BRACKET,
                ];
                $squareBracket = $phpcsFile->findPrevious($brackets, $stackPtr - 1, $lastBracket);
                if ($squareBracket !== false && $tokens[$squareBracket]['code'] === T_OPEN_SQUARE_BRACKET) {
                    $closeSquareBracket = $phpcsFile->findNext($brackets, $stackPtr + 1);
                    if ($closeSquareBracket !== false && $tokens[$closeSquareBracket]['code'] === T_CLOSE_SQUARE_BRACKET) {
                        $this->addMissingBracketsError($phpcsFile, $stackPtr);
                    }
                }
                return;
            }
        }
        
        //end if
        $lastAssignment = $phpcsFile->findPrevious(Tokens::$assignmentTokens, $stackPtr, null, false, null, true);
        if ($lastAssignment !== false && $lastAssignment > $lastBracket) {
            $this->addMissingBracketsError($phpcsFile, $stackPtr);
        }
    }
    
    //end process()
    
    /**
     * Add and fix the missing brackets error.
     *
     * @param \PHP_CodeSniffer\Files\File $phpcsFile The file being scanned.
     * @param int                         $stackPtr  The position of the current token in the
     *                                               stack passed in $tokens.
     *
     * @return void
     */
    public function addMissingBracketsError($phpcsFile, $stackPtr) {
        $tokens = $phpcsFile->getTokens();
        $allowed = [
            T_VARIABLE => true,
            T_LNUMBER => true,
            T_DNUMBER => true,
            T_STRING => true,
            T_CONSTANT_ENCAPSED_STRING => true,
            T_DOUBLE_QUOTED_STRING => true,
            T_WHITESPACE => true,
            T_NS_SEPARATOR => true,
            T_THIS => true,
            T_SELF => true,
            T_STATIC => true,
            T_OBJECT_OPERATOR => true,
            T_NULLSAFE_OBJECT_OPERATOR => true,
            T_DOUBLE_COLON => true,
            T_MODULUS => true,
            T_ISSET => true,
            T_ARRAY => true,
            T_NONE => true,
            T_BITWISE_NOT => true,
        ];
        // Find the first token in the expression.
        for ($before = $stackPtr - 1; $before > 0; $before--) {
            // Special case for plus operators because we can't tell if they are used
            // for addition or string contact. So assume string concat to be safe.
            if ($phpcsFile->tokenizerType === 'JS' && $tokens[$before]['code'] === T_PLUS) {
                break;
            }
            if (isset(Tokens::$emptyTokens[$tokens[$before]['code']]) === true || isset(Tokens::$operators[$tokens[$before]['code']]) === true || isset(Tokens::$castTokens[$tokens[$before]['code']]) === true || isset($allowed[$tokens[$before]['code']]) === true) {
                continue;
            }
            if ($tokens[$before]['code'] === T_CLOSE_PARENTHESIS) {
                $before = $tokens[$before]['parenthesis_opener'];
                continue;
            }
            if ($tokens[$before]['code'] === T_CLOSE_SQUARE_BRACKET) {
                $before = $tokens[$before]['bracket_opener'];
                continue;
            }
            if ($tokens[$before]['code'] === T_CLOSE_SHORT_ARRAY) {
                $before = $tokens[$before]['bracket_opener'];
                continue;
            }
            break;
        }
        
        //end for
        $before = $phpcsFile->findNext(Tokens::$emptyTokens, $before + 1, null, true);
        // A few extra tokens are allowed to be on the right side of the expression.
        $allowed[T_EQUAL] = true;
        $allowed[T_NEW] = true;
        // Find the last token in the expression.
        for ($after = $stackPtr + 1; $after < $phpcsFile->numTokens; $after++) {
            // Special case for plus operators because we can't tell if they are used
            // for addition or string concat. So assume string concat to be safe.
            if ($phpcsFile->tokenizerType === 'JS' && $tokens[$after]['code'] === T_PLUS) {
                break;
            }
            if (isset(Tokens::$emptyTokens[$tokens[$after]['code']]) === true || isset(Tokens::$operators[$tokens[$after]['code']]) === true || isset(Tokens::$castTokens[$tokens[$after]['code']]) === true || isset($allowed[$tokens[$after]['code']]) === true) {
                continue;
            }
            if ($tokens[$after]['code'] === T_OPEN_PARENTHESIS) {
                if (isset($tokens[$after]['parenthesis_closer']) === false) {
                    // Live coding/parse error. Ignore.
                    return;
                }
                $after = $tokens[$after]['parenthesis_closer'];
                continue;
            }
            if ($tokens[$after]['code'] === T_OPEN_SQUARE_BRACKET || $tokens[$after]['code'] === T_OPEN_SHORT_ARRAY) {
                if (isset($tokens[$after]['bracket_closer']) === false) {
                    // Live coding/parse error. Ignore.
                    return;
                }
                $after = $tokens[$after]['bracket_closer'];
                continue;
            }
            break;
        }
        
        //end for
        $after = $phpcsFile->findPrevious(Tokens::$emptyTokens, $after - 1, null, true);
        $error = 'Operation must be bracketed';
        if ($before === $after || $before === $stackPtr || $after === $stackPtr) {
            $phpcsFile->addError($error, $stackPtr, 'MissingBrackets');
            return;
        }
        $fix = $phpcsFile->addFixableError($error, $stackPtr, 'MissingBrackets');
        if ($fix === true) {
            // Can only fix this error if both tokens are available for fixing.
            // Adding one bracket without the other will create parse errors.
            $phpcsFile->fixer
                ->beginChangeset();
            $phpcsFile->fixer
                ->replaceToken($before, '(' . $tokens[$before]['content']);
            $phpcsFile->fixer
                ->replaceToken($after, $tokens[$after]['content'] . ')');
            $phpcsFile->fixer
                ->endChangeset();
        }
    }
    
    //end addMissingBracketsError()

}

//end class