Long Method

A Long Method is any method that has a large number of lines.

Current Support in Reek

Currently Long Method warns about any method that has more than 5 “statements”. Reek’s smell detector for Long Method counts +1 for every simple statement in a method and +1 for every statement within a control structure (if, else, case, when, for, while, until, begin, rescue — but it doesn’t count the control structure itself.

So the following method would score +6 in Reek’s statement-counting algorithm:

def parse(arg, argv, &error)
  if !(val = arg) and (argv.empty? or /\A-/ =~ (val = argv[0]))
    return nil, block, nil                                         # +1
  end
  opt = (val = parse_arg(val, &error))[1]                          # +2
  val = conv_arg(*val)                                             # +3
  if opt and !arg
    argv.shift                                                     # +4
  else
    val[0] = nil                                                   # +5
  end
  val                                                              # +6
end

(You might argue that the two assigments within the first if should count as statements, and that perhaps the nested assignment should count as +2. If you do, please feel free to vote up ticket #32.)

Configuration

Reek’s Long Method detector supports the Basic Smell Options, plus:

Long Method’s default configuration is:

---
LongMethod: 
  max_statements: 5
  exclude: 
  - initialize
  enabled: true

By default, initialize is not checked for length; any class’s constructor can be as long as necessary.