The Problem
It took me five days to solve the problem fully, to come up with a robust design.  But, it took me only five minutes to write an end-to-end test that passed.  The point I want to make, just in case it’s not obvious, is that it took me not one but two orders of magnitude longer to solve the problem than it took to ‘get it working’.  Going from ‘getting it working‘ to a proper system, I think, is where all the time on a software project goes.  It also accounts for all the head scratching - ‘but it was working last week’.

I decided to post this blog because I would like other people to have a go at solving the problem and I wanted to share my experiences.  In the next few weeks, I hope to post more about how I solved this problem, about how I worked outwards from the initial solution to the work of beauty that now sits on my hard drive.  Finally, I used, for the first time, WindowLicker, an open source framework, and I wanted to give it (and its creators) a shout out.



Input Data


Name,Address,Postcode,Phone,Credit Limit,Birthday

"Johnson, John",Voorstraat 32,3122gg,020 3849381,10000,01/01/1987
"
Anderson, Paul",Dorpsplein 3A,4532 AA,030 3458986,109093,03/12/1965


Output Data

<table border="1">

<tr>

  <td id='name'>Name</td><td id='address'>Address</td><td id='postcode'>Post Code</td><td id='phone'>Phone Number</td><td id='credit_limit'>Credit Limit</td><td id='birthday'>D.O.B.</td></tr>

  <tr><td id=1.1>Johnson, John</td><td id=1.2>Voorstraat 32</td><td id=1.3>3122gg</td><td id=1.4>020 3849381</td><td id=1.5>10000</td><td id=1.6>01/01/1987</td>
</tr>
<tr>
  <td id=2.1>Anderson, Paul</td><td id=2.2>Dorpsplein 3A</td><td id=2.3>4532 AA</td><td id=2.4>030 3458986</td><td id=2.5>109093</td><td id=2.6>03/12/1965</td>
</tr>

</table>

I always start my projects off with a test driver and an end-to-end test. This blog is about the end-to-end test.  The next blog is about the driver.  It’s important to know why these two play together.

Test Driver
A test driver is a simple tool for pushing data into the system under test.  On a real project, the test driver is useful to the programmer and testers, both of whom want real-time feedback from the system under test, and to the project managers and stakeholders as one way to gauge progress.  Any bugs found using the driver are always captured as automated tests.



Test drivers come in a number of forms.  At the beginning of our careers, we often use a main method and enter data via the command prompt.  As we develop, and start to use test-driven-development, we might rely on unit tests as our drivers.  When I work in finance, developing models (sometimes in C# or MatLab), a perfect test-driver is Microsoft’s Excel.

A test driver allows the testers to optimise their work and the optimised work of testers in turn drives the development of the system.  A programmer wants to code, wants to get ‘it’ working.  An engineer wants to enable themselves and the people around them.  It is the latter (and good project managers) who want test drivers to be written; they know that without them the actual time to complete the project will be three or four orders of magnitude longer.



End-To-End Test
There can be no object-oriented development without automated testing.  Roughly, we do get it working, that’s what takes five minutes, but we then grow our design outwards.  Every time we move a class, pull out some duplicate code, or tidy up a loop, we are designing.  Every time we design, we need to know that we haven’t broken the system.  An automated end-to-end test allows us to do this, it provides a safety net.  In our first attempts at writing the end-to-end test, we really are testing; we are learning about the system we are developing, we are considering, for a given set of inputs, what the outputs should or could be.  The system and the end-to-end test grow together (and in the background, the test driver does, too).  This is known as the co-evolution of a problem and solution (where the problem is captured in the test and updated as we find out more information):

It is widely accepted that creative design is not a matter of first fixing the problem and then searching for a satisfactory solution concept; instead it seems more to be a matter of developing and refining together both the formulation of the problem and ideas for its solution, with constant iterations of analysis, synthesis and evaluation processes between the two “spaces” - problem and solution.  (Cross & Dorst, 1999.)

As the system stabilises, as what we want it to do becomes clear and is captured in the code, the evolution of the end-to-end test (may) slow down.  At this point, our design may be a long way from complete, but the software is functional.  The end-to-end test becomes an end-to-end check, it verifies what we already know.  It confirms existing beliefs.  (Checking is a process of ‘confirmation, verification and validation’.  Testing is a process of ‘exploration, discovery, investigation, and learning’.)^{Bolton, 'Blog: Testing vs. Checking'.}

There we have it.  My stall is quite clear: there is no object-oriented design without automated checks.  There is no object-oriented design without exploratory testing (which is easier to do with decent tools that in the old days we called test drivers).



End-to-End Test - The Code
The first thing I did was extend one of WindowLicker’s classes, the ‘AbstractWebTest’.





public class EndToEnd extends AbstractWebTest {




private static final String HTML_FILE = "/Users/jamiedobson/desktop/original_table.html";


private static final String INPUT_DATA = "data/Workbook_two_entries.csv";

@Before
public void open() throws MalformedURLException {
  

openFile(new File(HTML_FILE));

}

@Test
public void headers()  {

 
  
  browser.element(By.id("name")).assertText(equalTo("Name"));

  
  browser.element(By.id("address")).assertText(equalTo("Address"));

  
  browser.element(By.id("postcode")).assertText(equalTo("Post Code"));

  
  browser.element(By.id("phone")).assertText(equalTo("Phone Number"));

  
  browser.element(By.id("credit_limit")).assertText(equalTo("Credit Limit"));
   
  
  browser.element(By.id("birthday")).assertText(equalTo("D.O.B."));
}




@Test
public void contents() {
   
  
  browser.element(By.id("1.1")).assertText(equalTo("Johnson, John"));

  browser.element(By.id("1.2")).assertText(equalTo("Voorstraat 32"));
      
  
  browser.element(By.id("1.3")).assertText(equalTo("3122gg"));
 
  browser.element(By.id("1.4")).assertText(equalTo("020 3849381"));
    
  
  browser.element(By.id("1.5")).assertText(equalTo("10000"));
   
  browser.element(By.id("1.6")).assertText(equalTo("01/01/1987"));
   
  
  browser.element(By.id("2.1")).assertText(equalTo("Anderson, Paul"));
   
  browser.element(By.id("2.2")).assertText(equalTo("Dorpsplein 3A"));
     
  
  browser.element(By.id("2.3")).assertText(equalTo("4532 AA"));
   
  browser.element(By.id("2.4")).assertText(equalTo("030 3458986"));
   
  
  browser.element(By.id("2.5")).assertText(equalTo("109093"));
   
  browser.element(By.id("2.6")).assertText(equalTo("03/12/1965"));

}



@BeforeClass
public static void setUpFixture() throws IOException, ParseException {
   
  assertTargetFileDoesNotExist();
   
  buildHtmlFile();

}

private static void buildHtmlFile() throws IOException {
  
  String footer = "</body><html>";
  
  String header = "<html><body><table border="1"><tr><td id='name'>Name</td>" 
+ "<td id='address'>Address</td><td id='postcode'>Post Code</td>"
+ "<td id='phone'>Phone Number</td><td id='credit_limit'>Credit Limit</td>"
+ "<td id='birthday'>D.O.B.</td></tr>";
   
  Writer writer = new FileWriter(new File(HTML_FILE));
   
  writer.write(header);
 
   int count = 1;
   
  Scanner data = new Scanner(new File(INPUT_DATA));
 
  data.nextLine();
 
  while (data.hasNext()) {
     
    writer.write("<tr>");
    Scanner lineScanner = new Scanner(data.nextLine());
     
    lineScanner.findInLine(""");
   
    lineScanner.useDelimiter(",");

    String surname = lineScanner.next().replaceAll(""", "");

    String firstName = lineScanner.next().replaceAll(""", "").trim();
     
    writer.write("<td id='" + count + ".1'>" + surname + ", " + firstName);
  
    writer.write("<td id='" + count + ".2'>" + lineScanner.next() + "</td>");
  
    writer.write("<td id='" + count + ".3'>" + lineScanner.next() + "</td>");
     
    writer.write("<td id='" + count + ".4'>" + lineScanner.next() + "</td>");
     
    writer.write("<td id='" + count + ".5'>" + lineScanner.next() + "</td>");
     
    writer.write("<td id='" + count + ".6'>" + lineScanner.next() + "</td>");
     
    writer.write("</tr>");
     count++;
   }  
  
    writer.write(footer);

    writer.close();

  }
}

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