YOU CAN’TMISS WHATYOU CAN’T MEASURE

Y’uh can’ git the’uh fruhm he’uh

[You can’t get there from here]

RED ➭ GREEN ➭ REFACTOR

1. Denial2. Anger3. Bargaining4. Depression5. Acceptance

1. Depression2. Bargaining3. Anger4. Acceptance5. Denial

@customers = Person.find_by_contents(@phrase, :columns => ['first_name', 'last_name', 'business_name', 'email_address', 'phone1'], :include => { :contacts => :customer }, :limit => 50).collect { |person| person.contacts.collect { |contact| contact.customer } }.flatten

{10:51}[1.9.3]~/project:master ✓ ➭ git blame app/controllers/customers_... ... cf2ee204 (Kerri Miller 2012-02-18 12:09:22 -0700 36)

TEST COVERAGE

TEST COVERAGEC0 — % of lines of code that have been executed

C1 — % of branches that have been followed at least once C2 — % of unique paths through the source code that have been followed

LINES OF CODE

LINES OF CODE{20:32}[1.9.3]~/project:master ✓ ➭ rake stats

+----------------------+-------+-------+---------+---------+-----+-------+| Name | Lines | LOC | Classes | Methods | M/C | LOC/M |+----------------------+-------+-------+---------+---------+-----+-------+| Controllers | 2297 | 1566 | 18 | 106 | 5 | 12 || Helpers | 177 | 137 | 0 | 18 | 0 | 5 || Models | 3948 | 2522 | 35 | 272 | 7 | 7 || Libraries | 164 | 92 | 4 | 12 | 3 | 5 || Model specs | 2863 | 2143 | 1 | 2 | 2 | 1069 || View specs | 5 | 3 | 0 | 0 | 0 | 0 || Controller specs | 4283 | 3632 | 0 | 0 | 0 | 0 || Helper specs | 152 | 108 | 0 | 0 | 0 | 0 || Library specs | 51 | 36 | 0 | 0 | 0 | 0 |+----------------------+-------+-------+---------+---------+-----+-------+| Total | 13940 | 10239 | 58 | 410 | 7 | 22 |+----------------------+-------+-------+---------+---------+-----+-------+ Code LOC: 4317 Test LOC: 5922 Code to Test Ratio: 1:1.4

STATIC vs DYNAMIC

"Data is easy. Information is hard."

-Dr Ying Li

COMPLEXITY

CYCLOMATIC

lin·e·ar·li

ASSIGNMENTSBRANCHESCONDITIONALS

class Test  def blah             a = eval "1+1" # 1.2 (a=) + 6.0 (eval)    if a == 2 then # 1.2 (if) + 1.2(==) + 0.4 (fixnum)      puts "yay"   # 1.2 (puts)    end  endend # 11.2 total

FLOG

• Extract Method• Decompose Objects• Rethink your domain model

CHURN

app/models/user.rb = 84

app/models/invoice.rb = 88

Wonderland Trail

Length:47.2 miles

Wonderland Trail

Length:47.2 miles

app/models/user.rb = 84

app/models/invoice.rb = 88

{10:54}[1.9.3]~/project:master ✓ ➭ git blame app/models/subscription.rb ... c9ce82b4 (Kerri Miller 2012-05-18 10:19:47 -0700

{20:32}[1.9.3]~/project:master ✓ ➭ flog -a app/models/subscription.rb 1609.9: flog total 61.9: flog/method average

408.8: Subscription#update app/models/subscription.rb:472 323.2: Subscription#new app/models/subscription.rb:250 252.0: Subscription#reply app/models/subscription.rb:137 230.5: Subscription::send_notifications app/models/subscription.rb:78 33.6: Subscription#none 25.5: Subscription#can_expire? app/models/subscription.rb:155 11.7: Subscription::reject_no_ack app/models/subscription.rb:205 4.8: Subscription#initialize app/models/subscription.rb:64 4.4: Subscription#expire! app/models/subscription.rb:183 3.7: Subscription#unexpire! app/models/subscription.rb:194 3.4: Subscription#reason_text app/models/subscription.rb:172 2.2: Subscription#is_current? app/models/subscription.rb:178 2.0: Subscription#to_s app/models/subscription.rb:71

{20:33}[1.9.3]~/project:master ✓ ➭ flog -d app/models/subscription.rb 321.7: flog total 32.2: flog/method average

230.5: Subscription::send_notifications app/models/subscription.rb:78 47.8: branch 31.7: ticket 23.1: assignment 17.9: user 17.6: [] 12.2: empty? 9.8: support_queue 8.1: deliver 8.0: class 7.6: email_address 7.0: ==

{08:16}[1.9.3]~/project:master ✓ ➭ flog -a app/models/subscription.rb

52.8: Subscription::send_notifications app/models/subscription.rb:80 28.8: Subscription#none 25.5: Subscription#can_expire? app/models/subscription.rb:119 10.2: Subscription::set_mail_options app/models/subscription.rb:221 9.8: Subscription::email_staff app/models/subscription.rb:268 8.5: Subscription::filter_subscriptions app/models/subscription.rb:17 7.9: Subscription::email_reviewers app/models/subscription.rb:258 7.3: Subscription::email_subscribers app/models/subscription.rb:169 6.3: Subscription::subscriber_emails app/models/subscription.rb:204 5.0: Subscription::log_rate_limited app/models/subscription.rb:239 4.8: Subscription#initialize app/models/subscription.rb:65 4.7: Subscription::extract_email_addresses app/models/subscription.rb 4.6: Subscription::filter_rate_limited app/models/subscription.rb:248 4.4: Subscription#expire! app/models/subscription.rb:147 4.0: Subscription::wants_notifications_on_own_posts? app/models/subsc 3.7: Subscription#unexpire! app/models/subscription.rb:158 3.4: Subscription#reason_text app/models/subscription.rb:136 3.2: Subscription::valid_recipient? app/models/subscription.rb:187 2.4: Subscription::ok_to_email? app/models/subscription.rb:183 2.2: Subscription#is_current? app/models/subscription.rb:142 2.0: Subscription#to_s app/models/subscription.rb:73 1.5: Subscription::find_reviewers app/models/subscription.rb:254 1.4: Subscription::mail_subject app/models/subscription.rb:217

{08:43}[1.9.3]~/project:master ✓ ➭ flog -a app/models/subscription.rb 27.9: Subscription#none 25.5: Subscription#can_expire? app/models/subscription.rb:78 4.8: Subscription#initialize app/models/subscription.rb:65 4.4: Subscription#expire! app/models/subscription.rb:106 3.7: Subscription#unexpire! app/models/subscription.rb:117 3.4: Subscription#reason_text app/models/subscription.rb:95 2.2: Subscription#is_current? app/models/subscription.rb:101 2.0: Subscription#to_s app/models/subscription.rb:73

{08:43}[1.9.3]~/project:master ✓ ➭ flog -a app/models/subscriber_notifier.rb 136.6: flog total 8.5: flog/method average

54.1: SubscriberNotifier::send_notifications app/models/subscriber_notif 12.0: SubscriberNotifier::email_subscribers app/models/subscriber_notifi 10.2: SubscriberNotifier::set_mail_options app/models/subscriber_notifie 9.8: SubscriberNotifier::email_staff app/models/subscriber_notifier.rb 8.5: SubscriberNotifier::filter_subscriptions app/models/subscriber_not 7.9: SubscriberNotifier::email_reviewers app/models/subscriber_notifier 6.3: SubscriberNotifier::subscriber_emails app/models/subscriber_notifi 5.0: SubscriberNotifier::log_rate_limited app/models/subscriber_notifie 4.7: SubscriberNotifier::extract_email_addresses app/models/subscriber_ 4.6: SubscriberNotifier::filter_rate_limited app/models/subscriber_noti 4.0: SubscriberNotifier::wants_notifications_on_own_posts? app/models/s 3.2: SubscriberNotifier::valid_recipient? app/models/subscriber_notifie 2.4: SubscriberNotifier::ok_to_email? app/models/subscriber_notifier.rb

> gem install flay

rails_best_practices reek roodi pelusa cane

BEST PRACTICES & STYLE

THANKS!★ @kerrizor

★ glass artist

★ vespa mechanic

★ lighting designer

★ professional poker player

★ Senior Developer @ Amazon, Contour.com, Blue Box Group