| Conditions | 10 | 
| Total Lines | 53 | 
| Lines | 0 | 
| Ratio | 0 % | 
| Changes | 0 | ||
Small methods make your code easier to understand, in particular if combined with a good name. Besides, if your method is small, finding a good name is usually much easier.
For example, if you find yourself adding comments to a method's body, this is usually a good sign to extract the commented part to a new method, and use the comment as a starting point when coming up with a good name for this new method.
Commonly applied refactorings include:
If many parameters/temporary variables are present:
Complex classes like SchedulesHelper.balanced_session_columns_for_slot() often do a lot of different things. To break such a class down, we need to identify a cohesive component within that class. A common approach to find such a component is to look for fields/methods that share the same prefixes, or suffixes.
Once you have determined the fields that belong together, you can apply the Extract Class refactoring. If the component makes sense as a sub-class, Extract Subclass is also a candidate, and is often faster.
| 1 | module SchedulesHelper | ||
| 25 | # (Without this, the fully expanded details grow very lopsided.) | ||
| 26 | # | ||
| 27 | def balanced_session_columns_for_slot(slot, &block) | ||
| 28 | |||
| 29 |     unassigned = slot.sessions.sort_by { |s| -estimated_height(s) } | ||
| 30 | |||
| 31 | columns = [[], []] | ||
| 32 | heights = [0, 0] | ||
| 33 | i = 0 | ||
| 34 | first = true | ||
| 35 | until unassigned.empty? | ||
| 36 | if unassigned.size == 1 && columns[0].size == columns[1].size # odd number of sessions, so last one can go in either column | ||
| 37 | i = if heights[0] < heights[1] | ||
| 38 | 0 | ||
| 39 | else | ||
| 40 | 1 | ||
| 41 | end | ||
| 42 | end | ||
| 43 | |||
| 44 | if first | ||
| 45 | # Start by placing longest description | ||
| 46 | session = unassigned.shift | ||
| 47 | first = false | ||
| 48 | else | ||
| 49 | # Greedy algo: choose next session to try to keep heights as close as possible | ||
| 50 | desired_height = heights[1-i] - heights[i] | ||
| 51 | session = nil | ||
| 52 | best_diff = 1 / 0.0 | ||
| 53 | unassigned.each do |candidate| # O(n^2), so watch this one if we start assigning lots of sessions per slot! | ||
| 54 | diff = (estimated_height(candidate) - desired_height).abs | ||
| 55 | if diff < best_diff | ||
| 56 | best_diff = diff | ||
| 57 | session = candidate | ||
| 58 | end | ||
| 59 | end | ||
| 60 | unassigned.delete(session) | ||
| 61 | end | ||
| 62 | break unless session | ||
| 63 | |||
| 64 | columns[i] << session | ||
| 65 | heights[i] += estimated_height(session) | ||
| 66 | i = 1-i | ||
| 67 | end | ||
| 68 | |||
| 69 | # Now yield each column with session sorted by room size. | ||
| 70 | |||
| 71 |     columns.map! { |col| col.sort_by { |s| session_sort_order(s) } } | ||
| 72 | unless columns[0].empty? || columns[1].empty? | ||
| 73 | if columns[0].first.attendance_count < columns[1].first.attendance_count | ||
| 74 | columns = [columns[1], columns[0]] | ||
| 75 | end | ||
| 76 | end | ||
| 77 | |||
| 78 | columns.each(&block) | ||
| 98 | |||