The Importance of Software Testing :The Importance of Software Testing


A Necessary Evil :A Necessary Evil All project managers know that they must do some testing The basic questions are; How much? What sort? By whom? When and by when? All difficult questions.


Why do we test? :Why do we test? Provide confidence in the system Identify areas of weakness Establish the degree of quality Establish the extent that the requirements have been met, i.e. what the users asked for is what they got not what someone else though they wanted To provide an understanding of the overall system To prove it is both usable and operable To provide sufficient information to allow an objective decision on applicability to deploy


Another view – cynical? :Another view – cynical? To use up spare budget To provide a good excuse why the project is late To provide jobs for people who can’t code To make the developers look good To provide the project manager with some contingency in the plan and can be cut if if push come to shove!


First up – How much? :First up – How much? How good does the product need to be? How do we measure it? How do we make a decision? Are there any legal or compliance issues? What industry are you in? What will it cost? Time and resource [human and machine] Are we capable? We know what we need to do but can we do it?


How do we decide? :How do we decide? What matters to our users? What does the system do? Risk Requirements Money Test Techniques - Coverage Static Dynamic


Secondly – What sort? :Secondly – What sort? Unit Interface Functionality Performance Usability Security Availability Operability ………plus about another 20 ‘abilities’ ?


Do we need tools to help? :Do we need tools to help? Automated test tools are often seen as a silver bullet Some tests cannot be successfully executed or analysed without them 80% of test tools end up as shelfware through: Abandonment Neglect Banishment


Thirdly – By whom? :Thirdly – By whom? Users: those who will ultimately use the system Customers: those who define the system – are they the same as the users? Testers Analysts Developers


Are we capable of testing? :Are we capable of testing? Is an experienced tester better than an experienced user at finding faults? How can testers help themselves and users? Working with the users to understand their systems Providing testing skills transfer Attending testing industry conferences Attaining industry recognised software testing qualifications


Lastly – When? :Lastly – When? Once the code is complete? As soon as the architecture is defined? Once the system delivery is complete? During development? Once the business requirements have been defined? As soon as the project is given the go-ahead?


Slide 12:Test then Code Then test some more……………………


By when? :Project deadline driven by: Legislation Arbitrary date Financial year Calendar date Seasonal Marketing window Safety Criticality Money By when?


Summary :Summary Testing is an integral part of the system development function, not an afterthought: Testing starts with the requirements not the code Testing is a static and dynamic activity Prevention is better than cure The sooner you find the fault the cheaper it is to fix Create re-usable ‘testware’ Process first then tools Not everyone can test well, use professional testers Planned testing in a controlled environment provides objective metrics To gain a Return on Investment you must first Invest