1.3 Testing Principles Flashcards
Testing Principles:
1. Testing shows the …
presence, not absence of defects.
Testing reduces the probability of defects remaining …
But even if no defects are found …
undiscovered in the test object
testing can’t prove test object correctness.
Testing Principles:
2. Exhaustive
testing is impossible.
Rather than attempting to test exhaustively:
- test t…
- test c…
- risk-b…
- test techniques
- test case prioritization
- risk-based testing should be used to focus test efforts.
Testing Principles:
3. Early …
testing saves time and money.
Defects removed early in the process will not cause subsequent …
defects in derived work products.
Quality cost will be …
reduced since fewer failures will occur later in the SDLC.
To find defects early …
Static testing and dynamic testing should be started as soon as possible.
Testing Principles:
4. Defects …
cluster together.
A small number of system components usually contain most … or are responsible for most…
of the discovered defects
of the operational failures.
Illustrated example of …
Pareto principle.
Predicted defect clusters and actual defect clusters observed during … are important input …
testing or in operation
for risk-based testing.
Testing Principles:
5. Tests …
wear out.
If the same tests are … they become increasingly …
repeated many times,
ineffective in detecting new defects.
To overcome this effect, existing … and new tests may …
tests and test data may need to be modified
need to be written.
However, in some cases repeating the same tests … e.g. in automated …
can have a beneficial outcome,
regression testing.
Testing Principles:
6. Testing is c…
context dependent.
Testing is done differently in …
different contexts.
Testing Principles:
7. Absence-of-…
defects fallacy.
It is a fallacy (i.e. a misconception) to expect that software verification will …
ensure system success.
Thoroughly testing all the specified requirements and fixing all the defects found could still produce a system that:
- does not fulfill…
- does not help in…
- is inferior…
- the users’ needs and expectations
- achieving the customer’s business goals
- compared to other competing systems
In addition to verification …
validation should also be carried out.
