piccolo coding dojo (milano xpug 2013-04-11)

Piccolo Coding DojoXPUG Milano 10 aprile 2013

Andrea Franciahttp://andreafrancia.it

Thursday, April 11, 13

http://andreafrancia.it

http://andreafrancia.it

Timetable

• A short review of TDD (1pom)

• Practice with TDD (2pom)

• Retrospective (1pom)


Test Driven Development


The heart of TDD

1. write a test

2. watch it fail

3. make it pass

4. repeat


Example: calculator


Example: file name extension


Three Rules of TDD

1. You can’t write any production code unless is to make green a red test

2. You can’t add more code to a test than is sufficient to make it red

3. You can’t write more production code than is sufficient to make the test green

http://butunclebob.com/ArticleS.UncleBob.TheThreeRulesOfTdd




Refactoring (def):

improving design without changing its observable behavior.


Refactoring (when)

• During the Green

refactor

make itpass

writeanother

test


Simple Design

A design is simple when:

1. pass all tests

2. contains no duplication

3. express the intent

4. minimal, nothing superfluous

http://c2.com/cgi/wiki?XpSimplicityRulesThursday, April 11, 13

http://c2.com/cgi/wiki?XpSimplicityRules

http://c2.com/cgi/wiki?XpSimplicityRules

What is not unit test?

A test is not a unit test if:

1. It talks to a database.

2. It communicates across a network.

3. It touches the file system.

4. Requires some manual set-up

Working Effectively with Legacy Code - Michael Feathers


http://www.amazon.com/s/ref=ntt_athr_dp_sr_1?_encoding=UTF8&field-author=Michael%20Feathers&search-alias=books&sort=relevancerank

http://www.amazon.com/s/ref=ntt_athr_dp_sr_1?_encoding=UTF8&field-author=Michael%20Feathers&search-alias=books&sort=relevancerank

Grazie


Domande?


Game of Life


THE GAME OF LIFE IS A TWO

DIMENSIONAL GRID OF SQUARE CELLS EACH OF WHICH IS

IN ONE OF TWO POSSIBLE STATES

ALIVE OR DEAD

http://www.slideshare.net/gabriele.lana/coderetreat




AT EACH STEP IN TIME EVERY CELL INTERACTS WITH ITS 8 NEIGHBORS

FOLLOWING 3 RULES





1. ANY LIVE CELL WITH FEWER THAN 2 LIVE NEIGHBORS DIES OF LONELINESS

http://www.slideshare.net/gabriele.lana/coderetreatThursday, April 11, 13



2. ANY LIVE CELL WITH MORE THAN 3 LIVE NEIGHBORS DIES OF OVERCROWDING




3. ANY DEAD CELL WITH EXACTLY 3 LIVE NEIGHBORS COMES TO LIFE OF WARMTH




LIFE EVOLUTION

1 2 3




LIFE EVOLUTION1 2 3




piccolo coding dojo (milano xpug 2013-04-11)

Technology