# Testing at Othoz
A brief introduction to Software Quality Assurance

## What is Testing?
- Testing measures the quality e.g., based on the number of located failures
- Testing increases the quality indirectly, as defects are detected which can be corrected prior to delivery
- Testing increases the process quality indirectly, as defects are documented which can then be analysed and help prevent similar errors from taking place in the future
- Testing increases the confidence in the quality of the system when few or no failures and defects are found

> Testing is economically useful, as long as the costs of finding and fixing a defect in testing are lower than the costs that are associated with the occurrence of a defect when used.

Testing effort in practice: 25% to 50% of development effort.

## Terminology
For an extensive glossary of all test terminology visit: http://glossary.istqb.org

- **Error**: Human action that produces an incorrect result
- **Defect** (aka bug): A flaw in a component or system (mostly the result of an error)
- **Failure**: The effect of a defect when executing a program
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- **Debugging**: Finds, analyzes and removes the causes of these failures
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- **Validation**: Did we implement the right system?
- **Verification**: Did we implement the system right?


## Seven Principles of Testing
Main principles that emerged from >50 years of Software Testing

1. Testing shows presence of failures (but cannot prove that there are no defects)
2. Exhaustive testing is impossible
3. Early testing
4. Defect clustering
5. Pesticide paradox (Repetitions have no effects)
6. Testing is context dependent
7. Absence-of-errors fallacy

## Software Quality Metrics

Following [ISO 25010](https://iso25000.com/index.php/en/iso-25000-standards/iso-25010):
![Image result for iso 25010](http://www.johner-institut.de/blog/wp-content/uploads/2011/12/121111_1340_TschssISO911.png)


## Fundamental Test Process
The test processes is closely linked with software development **but** is a separate, independent process. Testing **cannot** be considerd as a single activity (e.g. test execution), it includes many individual tasks.

The test process represents these individual testing activities in a coherent process.

### Planning and Controll
- Planning
	- Plan test resources (for us mainly person hours)
	- How instensive should we test what?
	- Which test techniques should be used?
	- Exit criteria (when did we test enough?)
	- Prioritizing tests (Risk = Likelihood * Impact)
	- Tool support? (flake8, pytest, codacy, bitbucket reviews, ...)
	- Schedule tasks for test analysis and test specification.
	- Schedule test implementation, test execution and test evaluation
- Controll
	- Measuring and analysing results
	- Monitor and record test processs (test coverage, exit critera)
	- Adapt time and resource planing

### Analysis and Design
### Implementation and Execution
### Report and Evaluation
### Test Closure


## Testing Throughout the Software Life Cycle
### The V-Model
![V-Model](http://www.softwaretestingstudio.com/wp-content/uploads/2017/04/V-Model-for-Software-Development-Life-Cycle.jpg)
new product versions
maintenance testing
regression testing
impact analysis

## Test Design Techniques
### Static Techniques
### Structure-based Techniques
### Experience-based Techniques
### Choosing Test Techniques

## Test Management
### Test Organization
### Planning and Estimation
### Test Progress Monitoring and Control
### Risk and Testing
### Incident Management