New rules: "Add space inside parens", "Add space inside square brackets"

[sergey-ilyin]

Need option to insert spaces inside parenthesis and square brackets.

"These spaces create very useful visual distinction between the function and their parameters, which helps a lot with avoiding the density that results from having no spaces there, visually merging the function name and parameters, increasing cognitive load." (quote from issue #1023)

Example of formatted code:

public let addSpaceInsideParens = FormatRule(
        help: "Add space inside parentheses."
    )
    { formatter in
        formatter.forEach( .startOfScope( "(" ) )
        { i, _ in
            if let nextToken = formatter.token( at: i + 1 )
            {
                if !nextToken.isSpaceOrLinebreak,
                   ![ .endOfScope( ")" ) ].contains( nextToken )
                {
                    formatter.insert( .space( " " ), at: i + 1 )
                }
            }
        }
        formatter.forEach( .endOfScope( ")" ) )
        { i, _ in
            if let prevToken = formatter.token( at: i - 1 )
            {
                if !prevToken.isSpaceOrLinebreak,
                   ![ .startOfScope( "(" ) ].contains( prevToken )
                {
                    formatter.insert( .space( " " ), at: i )
                }
            }
        }
    }

[nicklockwood]

Hi @sergey-ilyin, sorry for the delayed response. The idea behind these rules seems fine, but they conflict with the existing rules that remove those spaces, which isn't ideal. If someone were to accidentally enable both rules then the result would be random.

A better solution would be to make these into configuration options for the existing spaceInsideBrackets/Parens rules.