S3 SDD - Testing & Evaluation

Testing and evaluation

S3 Software Design & Development

​Testing and evaluation

Lesson objectives

• We are learning how to test and evaluate a basic calculation program

Success criteria

• I can create a test table for a basic calculation program

• I can evaluate a program's readability and fitness for purpose

​Testing a program

Once a program has been implemented, it must be tested to ensure it doesn't contain any errors.

​Question!

What would happen if a software development team were to hand over an untested piece of software to a client?

​Testing a program

A program should be thoroughly tested by first drawing up a testing table, this details expected and actual results along with giving the testing team a place to make comments when the software is tested. It allows the development team to record the results of running tests on the software.

​Test data	Expected result​	​Actual result	Comment​
​	​	​	​
​	​	​	​
​	​	​	​

​Practical task

Open a new Word document, place a heading with Testing at the top of the page and create the table below. There are 4 rows and columns.

​Test data	Expected result​	​Actual result	Comment​
​	​	​	​
​	​	​	​
​	​	​	​

Populate the first column entitled test data. Think about the inputs the user will be entering into your program.

Fill in the Blanks

​Practical task

Calculate the expected results from your test data and populate the Expected result column.

​Test data	Expected result​	​Actual result	Comment​
​MathsScore = 15 EnglishScore = 25 ComputingScore = 20	​	​	​
​MathsScore = 20 EnglishScore = 10 ComputingScore = 25	​	​	​
​MathsScore = 25 EnglishScore = 25 ComputingScore = 25	​	​	​

​Practical task

Run your program with the test data you created and populate the Actual result column.

​Test data	Expected result​	​Actual result	Comment​
​MathsScore = 15 EnglishScore = 25 ComputingScore = 20	​AverageScore = 20	​	​
​MathsScore = 20 EnglishScore = 10 ComputingScore = 25	​AverageScore = 18.3	​	​
​MathsScore = 25 EnglishScore = 25 ComputingScore = 25	​AverageScore = 25	​	​

​Practical task

Run your program with the test data you created and populate the Comment column.

​Test data	Expected result​	​Actual result	Comment​
​MathsScore = 15 EnglishScore = 25 ComputingScore = 20	​AverageScore = 20	​Average Score = 20.0	​
​MathsScore = 20 EnglishScore = 10 ComputingScore = 25	​AverageScore = 18.3	​Average Score = 18.333333333333332	​
​MathsScore = 25 EnglishScore = 25 ComputingScore = 25	​AverageScore = 25	​Average Score = 25.0	​

​Evaluation

Once a program has been thoroughly tested it should be evaluated. A piece of software is usually evaluated on whether:

• it is fit for purpose

• it is readable

• it uses coding constructs efficiently

• it is robust

​We will concentrate on fitness for purpose and code readability!

​Evaluation - Fitness for purpose

Software is deemed fit for purpose if it meets the requirements determined at the analysis phase. The original purpose and functional requirements can be used to decide if a program is fit for purpose.

It is often necessary to look at test table data to ensure the software is working as expected.

If software is not fit for purpose, it will be necessary to revisit previous phases of the development process. This is why the software development process is sometimes describes as iterative.

Open Ended

Describe the term iterative in relation to the software development process.

​Evaluation - Code readability

During the software development process numerous different teams may be involved in writing the software's code. It is therefore important to ensure that programming code is readable and can be understood by a programmer other than the person who wrote it. Program code can be made readable by ensuring the following are used:

• meaningful variable names

• internal commentary

• white space

• indentation

​Evaluation - Code readability

Program 1

Program 2

Draw

Identify the features which make this program code readable.

Open Ended

Evaluate whether you believe your program to be fit for purpose and readable.