lib/nice-space-before-function-paren.js
function getConfigForFunction(node)
    {
        if (isNamedFunction(node))
            return 'never';
        if (node.type === 'ArrowFunctionExpression')
        {
            // Always ignore non-async functions and arrow functions without parens, e.g.
            // `async foo => bar`.
            if
            (
                !node.async ||
                !astUtils.isOpeningParenToken(sourceCode.getFirstToken(node, { skip: 1 }))
            )
                return 'ignore';
        }
        return 'always';
    }
function getConfigForFunction(node)
    {
        if (isNamedFunction(node))
            return 'never';
        if (node.type === 'ArrowFunctionExpression')
        {
            // Always ignore non-async functions and arrow functions without parens, e.g.
            // `async foo => bar`.
            if
            (
                !node.async ||
                !astUtils.isOpeningParenToken(sourceCode.getFirstToken(node, { skip: 1 }))
            )
                return 'ignore';
        }
        return 'always';
    }
Gets the config for a given function.
@param {ASTNode} node The function node.
@returns {string} 'always', 'never', or 'ignore'.