parentheses_rule.coffee

# The main rule: I want to see a method call. Brackets are the most simple way to make it.

# if there is single argument and it is not a string, brackets required
fn()
fn(1)
fn(variable)

# if just single string, quotes are some kind of brackets here, and brackets can be omitted
fn 'string'

# if method is chainable, brackets required
fn.addClass('is-string')

# if there are more than one arguments, brackets requried
fn('string', variable)

# if argument doesn't fit one line, brackets can be omitted
fn 'string', variable, ->
  doSomething()

fn
  key: 'value'
  anotherKey: 'value'
  
# all other cases - brackets required
fn('string', variable, anotherFn)