PhpCsFixer\Fixer\FunctionNotation\FunctionDeclarationFixer::fix PHP Method

    public function fix(\SplFileInfo $file, Tokens $tokens)
    {
        $tokensAnalyzer = new TokensAnalyzer($tokens);
        for ($index = $tokens->count() - 1; $index >= 0; --$index) {
            $token = $tokens[$index];
            if (!$token->isGivenKind(T_FUNCTION)) {
                continue;
            }
            $startParenthesisIndex = $tokens->getNextTokenOfKind($index, array('(', ';', array(T_CLOSE_TAG)));
            if (!$tokens[$startParenthesisIndex]->equals('(')) {
                continue;
            }
            $endParenthesisIndex = $tokens->findBlockEnd(Tokens::BLOCK_TYPE_PARENTHESIS_BRACE, $startParenthesisIndex);
            $startBraceIndex = $tokens->getNextTokenOfKind($endParenthesisIndex, array(';', '{'));
            // fix single-line whitespace before {
            // eg: `function foo(){}` => `function foo() {}`
            // eg: `function foo()   {}` => `function foo() {}`
            if ($tokens[$startBraceIndex]->equals('{') && (!$tokens[$startBraceIndex - 1]->isWhitespace() || $tokens[$startBraceIndex - 1]->isWhitespace($this->singleLineWhitespaceOptions))) {
                $tokens->ensureWhitespaceAtIndex($startBraceIndex - 1, 1, ' ');
            }
            $afterParenthesisIndex = $tokens->getNextNonWhitespace($endParenthesisIndex);
            $afterParenthesisToken = $tokens[$afterParenthesisIndex];
            if ($afterParenthesisToken->isGivenKind(CT::T_USE_LAMBDA)) {
                // fix whitespace after CT:T_USE_LAMBDA (we might add a token, so do this before determining start and end parenthesis)
                $tokens->ensureWhitespaceAtIndex($afterParenthesisIndex + 1, 0, ' ');
                $useStartParenthesisIndex = $tokens->getNextTokenOfKind($afterParenthesisIndex, array('('));
                $useEndParenthesisIndex = $tokens->findBlockEnd(Tokens::BLOCK_TYPE_PARENTHESIS_BRACE, $useStartParenthesisIndex);
                // remove single-line edge whitespaces inside use parentheses
                $this->fixParenthesisInnerEdge($tokens, $useStartParenthesisIndex, $useEndParenthesisIndex);
                // fix whitespace before CT::T_USE_LAMBDA
                $tokens->ensureWhitespaceAtIndex($afterParenthesisIndex - 1, 1, ' ');
            }
            // remove single-line edge whitespaces inside parameters list parentheses
            $this->fixParenthesisInnerEdge($tokens, $startParenthesisIndex, $endParenthesisIndex);
            // remove whitespace before (
            // eg: `function foo () {}` => `function foo() {}`
            if (!$tokensAnalyzer->isLambda($index) && $tokens[$startParenthesisIndex - 1]->isWhitespace()) {
                $tokens[$startParenthesisIndex - 1]->clear();
            }
            // fix whitespace after T_FUNCTION
            // eg: `function     foo() {}` => `function foo() {}`
            $tokens->ensureWhitespaceAtIndex($index + 1, 0, ' ');
        }
    }