src/Tokenizer/Tokens.php
private function findOppositeBlockEdge($type, $searchIndex, $findEnd)
    {
        $blockEdgeDefinitions = self::getBlockEdgeDefinitions();

        if (!isset($blockEdgeDefinitions[$type])) {
            throw new \InvalidArgumentException(sprintf('Invalid param type: %s.', $type));
        }

        if (!self::isLegacyMode() && isset($this->blockEndCache[$searchIndex])) {
            return $this->blockEndCache[$searchIndex];
        }

        $startEdge = $blockEdgeDefinitions[$type]['start'];
        $endEdge = $blockEdgeDefinitions[$type]['end'];
        $startIndex = $searchIndex;
        $endIndex = $this->count() - 1;
        $indexOffset = 1;

        if (!$findEnd) {
            list($startEdge, $endEdge) = [$endEdge, $startEdge];
            $indexOffset = -1;
            $endIndex = 0;
        }

        if (!$this[$startIndex]->equals($startEdge)) {
            throw new \InvalidArgumentException(sprintf('Invalid param $startIndex - not a proper block %s.', $findEnd ? 'start' : 'end'));
        }

        $blockLevel = 0;

        for ($index = $startIndex; $index !== $endIndex; $index += $indexOffset) {
            $token = $this[$index];

            if ($token->equals($startEdge)) {
                ++$blockLevel;

                continue;
            }

            if ($token->equals($endEdge)) {
                --$blockLevel;

                if (0 === $blockLevel) {
                    break;
                }

                continue;
            }
        }

        if (!$this[$index]->equals($endEdge)) {
            throw new \UnexpectedValueException(sprintf('Missing block %s.', $findEnd ? 'end' : 'start'));
        }

        $this->blockEndCache[$startIndex] = $index;
        $this->blockEndCache[$index] = $startIndex;

        return $index;
    }
private function findOppositeBlockEdge($type, $searchIndex, $findEnd)
    {
        $blockEdgeDefinitions = self::getBlockEdgeDefinitions();

        if (!isset($blockEdgeDefinitions[$type])) {
            throw new \InvalidArgumentException(sprintf('Invalid param type: %s.', $type));
        }

        if (!self::isLegacyMode() && isset($this->blockEndCache[$searchIndex])) {
            return $this->blockEndCache[$searchIndex];
        }

        $startEdge = $blockEdgeDefinitions[$type]['start'];
        $endEdge = $blockEdgeDefinitions[$type]['end'];
        $startIndex = $searchIndex;
        $endIndex = $this->count() - 1;
        $indexOffset = 1;

        if (!$findEnd) {
            list($startEdge, $endEdge) = [$endEdge, $startEdge];
            $indexOffset = -1;
            $endIndex = 0;
        }

        if (!$this[$startIndex]->equals($startEdge)) {
            throw new \InvalidArgumentException(sprintf('Invalid param $startIndex - not a proper block %s.', $findEnd ? 'start' : 'end'));
        }

        $blockLevel = 0;

        for ($index = $startIndex; $index !== $endIndex; $index += $indexOffset) {
            $token = $this[$index];

            if ($token->equals($startEdge)) {
                ++$blockLevel;

                continue;
            }

            if ($token->equals($endEdge)) {
                --$blockLevel;

                if (0 === $blockLevel) {
                    break;
                }

                continue;
            }
        }

        if (!$this[$index]->equals($endEdge)) {
            throw new \UnexpectedValueException(sprintf('Missing block %s.', $findEnd ? 'end' : 'start'));
        }

        $this->blockEndCache[$startIndex] = $index;
        $this->blockEndCache[$index] = $startIndex;

        return $index;
    }
@param int  $type        type of block, one of BLOCK_TYPE_*
@param int  $searchIndex index of starting brace
@param bool $findEnd     if method should find block's end or start

@return int index of opposite brace