Symfony\Component\Routing\RouteCompiler::compilePattern()

Complexity

Conditions	40
Paths	> 20000

Size

Total Lines	135
Code Lines	79

Duplication

Lines	0
Ratio	0 %

Importance

Changes

0

<?php
    private static function compilePattern(Route $route, $pattern, $isHost)
    {
        $tokens = array();
        $variables = array();
        $matches = array();
        $pos = 0;
        $defaultSeparator = $isHost ? '.' : '/';
        $useUtf8 = preg_match('//u', $pattern);
        $needsUtf8 = $route->getOption('utf8');

        if (!$needsUtf8 && $useUtf8 && preg_match('/[\x80-\xFF]/', $pattern)) {
            $needsUtf8 = true;
            @trigger_error(sprintf('Using UTF-8 route patterns without setting the "utf8" option is deprecated since Symfony 3.2 and will throw a LogicException in 4.0. Turn on the "utf8" route option for pattern "%s".', $pattern), E_USER_DEPRECATED);
        }
        if (!$useUtf8 && $needsUtf8) {
            throw new \LogicException(sprintf('Cannot mix UTF-8 requirements with non-UTF-8 pattern "%s".', $pattern));
        }

        // Match all variables enclosed in "{}" and iterate over them. But we only want to match the innermost variable
        // in case of nested "{}", e.g. {foo{bar}}. This in ensured because \w does not match "{" or "}" itself.
        preg_match_all('#\{\w+\}#', $pattern, $matches, PREG_OFFSET_CAPTURE | PREG_SET_ORDER);
        foreach ($matches as $match) {
            $varName = substr($match[0][0], 1, -1);
            // get all static text preceding the current variable
            $precedingText = substr($pattern, $pos, $match[0][1] - $pos);
            $pos = $match[0][1] + strlen($match[0][0]);

            if (!strlen($precedingText)) {
                $precedingChar = '';
            } elseif ($useUtf8) {
                preg_match('/.$/u', $precedingText, $precedingChar);
                $precedingChar = $precedingChar[0];
            } else {
                $precedingChar = substr($precedingText, -1);
            }
            $isSeparator = '' !== $precedingChar && false !== strpos(static::SEPARATORS, $precedingChar);

            // A PCRE subpattern name must start with a non-digit. Also a PHP variable cannot start with a digit so the
            // variable would not be usable as a Controller action argument.
            if (preg_match('/^\d/', $varName)) {
                throw new \DomainException(sprintf('Variable name "%s" cannot start with a digit in route pattern "%s". Please use a different name.', $varName, $pattern));
            }
            if (in_array($varName, $variables)) {
                throw new \LogicException(sprintf('Route pattern "%s" cannot reference variable name "%s" more than once.', $pattern, $varName));
            }

            if (strlen($varName) > self::VARIABLE_MAXIMUM_LENGTH) {
                throw new \DomainException(sprintf('Variable name "%s" cannot be longer than %s characters in route pattern "%s". Please use a shorter name.', $varName, self::VARIABLE_MAXIMUM_LENGTH, $pattern));
            }

            if ($isSeparator && $precedingText !== $precedingChar) {
                $tokens[] = array('text', substr($precedingText, 0, -strlen($precedingChar)));
            } elseif (!$isSeparator && strlen($precedingText) > 0) {
                $tokens[] = array('text', $precedingText);
            }

            $regexp = $route->getRequirement($varName);
            if (null === $regexp) {
                $followingPattern = (string) substr($pattern, $pos);
                // Find the next static character after the variable that functions as a separator. By default, this separator and '/'
                // are disallowed for the variable. This default requirement makes sure that optional variables can be matched at all
                // and that the generating-matching-combination of URLs unambiguous, i.e. the params used for generating the URL are
                // the same that will be matched. Example: new Route('/{page}.{_format}', array('_format' => 'html'))
                // If {page} would also match the separating dot, {_format} would never match as {page} will eagerly consume everything.
                // Also even if {_format} was not optional the requirement prevents that {page} matches something that was originally
                // part of {_format} when generating the URL, e.g. _format = 'mobile.html'.
                $nextSeparator = self::findNextSeparator($followingPattern, $useUtf8);
                $regexp = sprintf(
                    '[^%s%s]+',
                    preg_quote($defaultSeparator, self::REGEX_DELIMITER),
                    $defaultSeparator !== $nextSeparator && '' !== $nextSeparator ? preg_quote($nextSeparator, self::REGEX_DELIMITER) : ''
                );
                if (('' !== $nextSeparator && !preg_match('#^\{\w+\}#', $followingPattern)) || '' === $followingPattern) {
                    // When we have a separator, which is disallowed for the variable, we can optimize the regex with a possessive
                    // quantifier. This prevents useless backtracking of PCRE and improves performance by 20% for matching those patterns.
                    // Given the above example, there is no point in backtracking into {page} (that forbids the dot) when a dot must follow
                    // after it. This optimization cannot be applied when the next char is no real separator or when the next variable is
                    // directly adjacent, e.g. '/{x}{y}'.
                    $regexp .= '+';
                }
            } else {
                if (!preg_match('//u', $regexp)) {
                    $useUtf8 = false;
                } elseif (!$needsUtf8 && preg_match('/[\x80-\xFF]|(?<!\\\\)\\\\(?:\\\\\\\\)*+(?-i:X|[pP][\{CLMNPSZ]|x\{[A-Fa-f0-9]{3})/', $regexp)) {
                    $needsUtf8 = true;
                    @trigger_error(sprintf('Using UTF-8 route requirements without setting the "utf8" option is deprecated since Symfony 3.2 and will throw a LogicException in 4.0. Turn on the "utf8" route option for variable "%s" in pattern "%s".', $varName, $pattern), E_USER_DEPRECATED);
                }
                if (!$useUtf8 && $needsUtf8) {
                    throw new \LogicException(sprintf('Cannot mix UTF-8 requirement with non-UTF-8 charset for variable "%s" in pattern "%s".', $varName, $pattern));
                }
            }

            $tokens[] = array('variable', $isSeparator ? $precedingChar : '', $regexp, $varName);
            $variables[] = $varName;
        }

        if ($pos < strlen($pattern)) {
            $tokens[] = array('text', substr($pattern, $pos));
        }

        // find the first optional token
        $firstOptional = PHP_INT_MAX;
        if (!$isHost) {
            for ($i = count($tokens) - 1; $i >= 0; --$i) {
                $token = $tokens[$i];
                if ('variable' === $token[0] && $route->hasDefault($token[3])) {
                    $firstOptional = $i;
                } else {
                    break;
                }
            }
        }

        // compute the matching regexp
        $regexp = '';
        for ($i = 0, $nbToken = count($tokens); $i < $nbToken; ++$i) {
            $regexp .= self::computeRegexp($tokens, $i, $firstOptional);
        }
        $regexp = self::REGEX_DELIMITER.'^'.$regexp.'$'.self::REGEX_DELIMITER.'sD'.($isHost ? 'i' : '');

        // enable Utf8 matching if really required
        if ($needsUtf8) {
            $regexp .= 'u';
            for ($i = 0, $nbToken = count($tokens); $i < $nbToken; ++$i) {
                if ('variable' === $tokens[$i][0]) {
                    $tokens[$i][] = true;
                }
            }
        }

        return array(
            'staticPrefix' => self::determineStaticPrefix($route, $tokens),
            'regex' => $regexp,
            'tokens' => array_reverse($tokens),
            'variables' => $variables,
        );