{"id":612,"date":"2014-01-09T13:42:48","date_gmt":"2014-01-09T13:42:48","guid":{"rendered":"https:\/\/agilestaffordshire.org\/?p=612"},"modified":"2014-01-23T18:14:53","modified_gmt":"2014-01-23T18:14:53","slug":"january-2014-kata-with-constraints","status":"publish","type":"post","link":"https:\/\/agilestaffordshire.org\/agile\/january-2014-kata-with-constraints\/","title":{"rendered":"January 2014 &#8211; Kata with Constraints"},"content":{"rendered":"<div style=\"width: 260px\" class=\"wp-caption alignright\"><a href=\"http:\/\/www.stockvault.net\/photo\/128634\/calculator-\" target=\"_blank\"><img alt=\"Calculator Kata\" src=\"\/wp-content\/uploads\/2014\/01\/stockvault-calculator-128634.jpg\" width=\"250\" \/><\/a><p class=\"wp-caption-text\">Calculator Kata<\/p><\/div>\n<p>Date:\u00a0<strong>Thursday 23rd\u00a0January 2014<\/strong><br \/>\nTime:\u00a0<strong>7:00pm<\/strong><br \/>\nVenue:\u00a0<strong><a href=\"http:\/\/goo.gl\/maps\/R9X5n\" target=\"_blank\">Staffordshire University &#8211; Stafford Campus<\/a>\u00a0(Octagon building, K102)<\/strong><\/p>\n<p>With the new year now behind us, to kick start 2014 Agile Staffordshire will be going back to basics with a twist. A key technique in agile development is Test Driven Development (TDD), a difficult skill to master yet often practiced through simple Kata exercises. For the uninitiated, Katas are a reference to martial arts where students repeatably\u00a0practice a set of moves in order to better learn and understand. Programming Katas are similar short 10-30 minute challenges where the goal is the same but each attempt can lead you to experience a different journey.<\/p>\n<p>This month we will be pairing together to do the <a href=\"http:\/\/osherove.com\/tdd-kata-1\/\" target=\"_blank\">String Calculator by Roy Osherove<\/a>\u00a0but with a constraint of your choosing. Kata rules are below, as are a selection of constraints but feel free to choose your own. There is no set language, but you will need one with a testing framework for TDD.<\/p>\n<h2>String Calculator<\/h2>\n<p>The following is a TDD Kata- an exercise in coding, refactoring and test-first, that you should apply daily for at least 15 minutes (I do 30).<\/p>\n<h2>Before you start:<\/h2>\n<ul>\n<li>Try not to read ahead.<\/li>\n<li>Do one task at a time.\u00a0The trick is to learn to work incrementally.<\/li>\n<li>Make sure you only test for<strong>\u00a0correct inputs<\/strong>. there is no need to test for invalid inputs for this kata<\/li>\n<\/ul>\n<p><strong>String Calculator<\/strong><\/p>\n<ol>\n<li>Create a simple String calculator with a method\u00a0<strong>int Add(string numbers)<\/strong>\n<ol>\n<li>The method can take 0, 1 or 2 numbers, and will return their sum (for an empty string it will return 0) for example<strong>\u00a0\u201c\u201d or \u201c1\u201d or \u201c1,2\u201d<\/strong><\/li>\n<li>Start with the simplest test case of an empty string and move to 1 and two numbers<\/li>\n<li>Remember to solve things as simply as possible so that you force yourself to write tests you did not think about<\/li>\n<li>Remember to refactor after each passing test<\/li>\n<\/ol>\n<\/li>\n<li>Allow the Add method to handle an unknown amount of numbers<\/li>\n<li>Allow the Add method to handle new lines between numbers (instead of commas).\n<ol>\n<li>the following input is ok:\u00a0 \u201c1\\n2,3\u201d\u00a0 (will equal 6)<\/li>\n<li>the following input is NOT\u00a0ok:\u00a0 \u201c1,\\n\u201d (not need to prove it &#8211; just clarifying)<\/li>\n<\/ol>\n<\/li>\n<li><strong>Support different delimiters<\/strong>\n<ol>\n<li>to change a delimiter, the beginning of the string will contain a separate line that looks like this:\u00a0\u00a0 \u201c\/\/[delimiter]\\n[numbers\u2026]\u201d for example \u201c\/\/;\\n1;2\u201d should return three where the default delimiter is \u2018;\u2019 .<\/li>\n<li>the first line is optional. all existing scenarios should still be supported<\/li>\n<\/ol>\n<\/li>\n<li>Calling Add with a negative number will throw an exception \u201cnegatives not allowed\u201d &#8211; and the negative that was passed.if there are multiple negatives, show all of them in the exception message<br \/>\n<hr \/>\n<p><strong>stop here if you are a beginner<\/strong>. Continue if you can finish the steps so far in less than 30 minutes.<\/p>\n<hr \/>\n<\/li>\n<li>Numbers bigger than 1000 should be ignored, so adding 2 + 1001 \u00a0= 2<\/li>\n<li>Delimiters can be of any length with the following format:\u00a0 \u201c\/\/[delimiter]\\n\u201d for example: \u201c\/\/[***]\\n1***2***3\u201d should return 6<\/li>\n<li>Allow multiple delimiters like this:\u00a0 \u201c\/\/[delim1][delim2]\\n\u201d for example \u201c\/\/[*][%]\\n1*2%3\u201d should return 6.<\/li>\n<li>make sure you can also handle multiple delimiters with length longer than one char<\/li>\n<\/ol>\n<h2><\/h2>\n<h2>Kata Constraints<\/h2>\n<p>Select <span style=\"text-decoration: underline;\">ONE<\/span> constraint from below.<\/p>\n<ul>\n<li>No If, Else, Switch Statements<\/li>\n<li>No mouse<\/li>\n<li>No Classes<\/li>\n<li>Use a functional language<\/li>\n<li>No Mutable State<\/li>\n<li>No Getters\/Setters<\/li>\n<li>No IDE<\/li>\n<li>2 Refactorings after each passing test<\/li>\n<li>Single word method names<\/li>\n<li>Or make one up yourself&#8230;<\/li>\n<\/ul>\n<p>Many of the constraints above which affect the design of code, work towards improving object calisthenics. More on this can be found <a href=\"http:\/\/www.mabishu.com\/blog\/2012\/12\/14\/object-calisthenics-write-better-object-oriented-code\/\">here.<\/a><\/p>\n<p>The goal of the session is not to complete the Kata <em>(you may even restart several times)<\/em> but to learn through the experience of your selected constraint.<\/p>\n<p>This will also be a special month, as it will be the last regular attendance of one of Agile Staffordshire&#8217;s founding members. Neil Kidd will be moving on to a new position at <a href=\"http:\/\/www.7digital.com\/\" target=\"_blank\">7Digital<\/a>, so all please wish him the best.<\/p>\n<p>Hope to see you there.<br \/>\nJon<\/p>\n<p>&nbsp;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Date:\u00a0Thursday 23rd\u00a0January 2014 Time:\u00a07:00pm Venue:\u00a0Staffordshire University &#8211; Stafford Campus\u00a0(Octagon building, K102) With the new year now behind us, to kick start 2014 Agile Staffordshire will be going back to basics with a twist. A key technique in agile development is Test Driven Development (TDD), a difficult skill to master yet often practiced through simple Kata [&hellip;]<\/p>\n","protected":false},"author":8,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"spay_email":"","jetpack_publicize_message":"","jetpack_is_tweetstorm":false},"categories":[3,4],"tags":[],"jetpack_featured_media_url":"","jetpack_publicize_connections":[],"jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/p4r37M-9S","_links":{"self":[{"href":"https:\/\/agilestaffordshire.org\/wp-json\/wp\/v2\/posts\/612"}],"collection":[{"href":"https:\/\/agilestaffordshire.org\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/agilestaffordshire.org\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/agilestaffordshire.org\/wp-json\/wp\/v2\/users\/8"}],"replies":[{"embeddable":true,"href":"https:\/\/agilestaffordshire.org\/wp-json\/wp\/v2\/comments?post=612"}],"version-history":[{"count":6,"href":"https:\/\/agilestaffordshire.org\/wp-json\/wp\/v2\/posts\/612\/revisions"}],"predecessor-version":[{"id":674,"href":"https:\/\/agilestaffordshire.org\/wp-json\/wp\/v2\/posts\/612\/revisions\/674"}],"wp:attachment":[{"href":"https:\/\/agilestaffordshire.org\/wp-json\/wp\/v2\/media?parent=612"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/agilestaffordshire.org\/wp-json\/wp\/v2\/categories?post=612"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/agilestaffordshire.org\/wp-json\/wp\/v2\/tags?post=612"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}