Testing Merb

The Right Way

Why Test?

TDD

TDD and Regressions

TDD and Regressions

I am not saying TDD is bad, but this talk doesn’t focus on mock-driven TDD.

Resiliant Against Refactoring

class Awesome def hello puts "~ Hello ~" endend

describe Awesome do it "prints hello" do awesome = Awesome.new awesome.should_receive(:puts) awesome.hello endend

class Awesome def hello awesome_print "~ Hello ~" end def awesome_print(str) print "#{str}\n" endend

describe Awesome do it "prints hello" do awesome = Awesome.new awesome.should_receive(:puts) awesome.hello endend

class Awesome def hello awesome_print "~ Hello ~" end def awesome_print(str) print "#{str}\n" endend

describe Awesome do it "prints hello" do awesome = Awesome.new awesome.should_receive(:puts) awesome.hello endend

FAIL

class Awesome def hello awesome_print "~ Hello ~" end def awesome_print(str) print "#{str}\n" endend

describe Awesome do it "prints hello" do capture { Awesome.new.hello }. should =~ /Hello/ endend

How to Test Three Rules

Broken Interface means failing tests

Working Interface means passing tests

Write tests about what you care about

http://example.com/foo

Controller

Filters

Views

Helpers

What Happens in Your App

Your App

http://example.com/foo

What You Care About

http://example.com/foo

Controller

4 Filters

Views

Helpers

H Partials

Refactoring

Iteration 1

class Foo < Application def awesome awesome_string end def awesome_string "Awesome" endend

Merb::Router.prepare do match("/foo/awesome"). to(:controller => Foo, :action => :awesome). name(:awesome)end

dispatch_to(Foo, :awesome) do |cont| cont.should_receive(:awesome_string)end

dispatch_to(Foo, :awesome) do |cont| cont.should_receive(:awesome_string)end

Iteration 2

class Bar < Application def coolness render end end

Merb::Router.prepare do match("/foo/awesome"). to(:controller => Bar, :action => :coolness). name(:awesome)end

dispatch_to(Foo, :awesome) do |cont| cont.should_receive(:awesome_string)end

dispatch_to(Foo, :awesome) do |cont| cont.should_receive(:awesome_string)end FAIL

request("/foo/awesome").body. should =~ /Awesome/

request(url(:awesome)).body. should =~ /Awesome/

Broken Interface means failing tests

Working Interface means passing tests

Write tests about what you care about

“It’s Too Hard”

Let’s Make it Easy

request(url(:speakers))

request(resource(@speaker))

request("/foo/speakers")

request(url(:speakers))

request(resource(@speaker))

request("/foo/speakers")

one method

Sessions are automatically sticky in a spec

it "should let you in" do request("/login", :method => :post, :params => {:username => "user", :password => "pass"}) request("/home").should be_successfulend

it "should let you in" do request("/login", :method => :post, :params => {:username => "user", :password => "pass"}) request("/home").should be_successfulend

login

it "should let you in" do request("/login", :method => :post, :params => {:username => "user", :password => "pass"}) request("/home").should be_successfulend

you’re logged in

describe "/login", :given => "successful login" do it "should let you in" do request("/home").should be_successful endend

simpler

describe "/login", :given => "successful login" do it "should let you in" do request("/home").should be_successful endend

simpler

Request

Rack

body headersstatus

request() helper

Rack

body headersstatus

request("/foo").body.should == "hello"

request("/foo").should have_xpath("//h1")

request("/foo").should( have_selector("h1:contains(text)"))

request("/foo").body.should == "hello"

request("/foo").should have_xpath("//h1")

request("/foo").should( have_selector("h1:contains(text)"))

1.0 final

request("/foo").should be_client_error

request("/foo").should( have_content_type(:json))

Thank you.