src/Fixer/FunctionNotation/StaticLambdaFixer.php
private function hasPossibleReferenceToThis(Tokens $tokens, $startIndex, $endIndex)
    {
        for ($i = $startIndex; $i < $endIndex; ++$i) {
            if ($tokens[$i]->isGivenKind(T_VARIABLE) && '$this' === strtolower($tokens[$i]->getContent())) {
                return true; // directly accessing '$this'
            }

            if ($tokens[$i]->isGivenKind([
                T_INCLUDE,                    // loading additional symbols we cannot analyze here
                T_INCLUDE_ONCE,               // "
                T_REQUIRE,                    // "
                T_REQUIRE_ONCE,               // "
                CT::T_DYNAMIC_VAR_BRACE_OPEN, // "$h = ${$g};" case
                T_EVAL,                       // "$c = eval('return $this;');" case
            ])) {
                return true;
            }

            if ($tokens[$i]->equals('$')) {
                $nextIndex = $tokens->getNextMeaningfulToken($i);
                if ($tokens[$nextIndex]->isGivenKind(T_VARIABLE)) {
                    return true; // "$$a" case
                }
            }
        }

        return false;
    }
private function hasPossibleReferenceToThis(Tokens $tokens, $startIndex, $endIndex)
    {
        for ($i = $startIndex; $i < $endIndex; ++$i) {
            if ($tokens[$i]->isGivenKind(T_VARIABLE) && '$this' === strtolower($tokens[$i]->getContent())) {
                return true; // directly accessing '$this'
            }

            if ($tokens[$i]->isGivenKind([
                T_INCLUDE,                    // loading additional symbols we cannot analyze here
                T_INCLUDE_ONCE,               // "
                T_REQUIRE,                    // "
                T_REQUIRE_ONCE,               // "
                CT::T_DYNAMIC_VAR_BRACE_OPEN, // "$h = ${$g};" case
                T_EVAL,                       // "$c = eval('return $this;');" case
            ])) {
                return true;
            }

            if ($tokens[$i]->equals('$')) {
                $nextIndex = $tokens->getNextMeaningfulToken($i);
                if ($tokens[$nextIndex]->isGivenKind(T_VARIABLE)) {
                    return true; // "$$a" case
                }
            }
        }

        return false;
    }
Returns 'true' if there is a possible reference to '$this' within the given tokens index range.

@param Tokens $tokens
@param int    $startIndex
@param int    $endIndex

@return bool