title: “Types of testing”
This type of testing is done to determine if a feature or system
meets the customer expectations and requirements.
This type of testing generally involves the customer’s
cooperation or feedback, being a validation activity that
answers the question:
Are we building the right product?.
For web applications, the automation of this testing can be done
directly with Selenium by simulating user expected behaviour.
This simulation could be done by record/playback or through the
different supported languages as explained in this documentation.
Note: Acceptance testing is a subtype of functional testing,
which some people might also refer to.
This type of testing is done to determine if a
feature or system functions properly without issues. It checks
the system at different levels to ensure that all scenarios
are covered and that the system does what’s
supposed to do. It’s a verification activity that
answers the question:
Are we building the product right?.
This generally includes: the tests work without errors
(404, exceptions…), in a usable way (correct redirections),
in an accessible way and matching its specifications
(see acceptance testing above).
For web applications, the automation of this testing can be
done directly with Selenium by simulating expected returns.
This simulation could be done by record/playback or through
the different supported languages as explained in this documentation.
As its name indicates, performance tests are done
to measure how well an application is performing.
There are two main sub-types for performance testing:
Load testing is done to verify how well the
application works under different defined loads
(usually a particular number of users connected at once).
Stress testing is done to verify how well the
application works under stress (or above the maximum supported load).
Generally, performance tests are done by executing some
Selenium written tests simulating different users
hitting a particular function on the web app and
retrieving some meaningful measurements.
This is generally done by other tools that retrieve the metrics.
One such tool is JMeter.
For a web application, details to measure include
throughput, latency, data loss, individual component loading times…
Note 1: All browsers have a performance tab in their
developers’ tools section (accessible by pressing F12)
Note 2: is a subtype of non-functional testing
as this is generally measured per system and not per function/feature.
This testing is generally done after a change, fix or feature addition.
To ensure that the change has not broken any of the existing
functionality, some already executed tests are executed again.
The set of re-executed tests can be full or partial
and can include several different types, depending
on the application and development team.
Test driven development (TDD)
Rather than a test type per se, TDD is an iterative
development methodology in which tests drive the design of a feature.
Each cycle starts by creating a set of unit tests that
the feature should eventually pass (they should fail their first time executed).
After this, development takes place to make the tests pass.
The tests are executed again, starting another cycle
and this process continues until all tests are passing.
This aims to speed up the development of an application
based on the fact that defects are less costly the earlier they are found.
Behavior-driven development (BDD)
BDD is also an iterative development methodology
based on the above TDD, in which the goal is to involve
all the parties in the development of an application.
Each cycle starts by creating some specifications
(which should fail). Then create the failing unit
tests (which should also fail) and then do the development.
This cycle is repeated until all types of tests are passing.
In order to do so, a specification language is
used. It should be understandable by all parties and
simple, standard and explicit.
Most tools use Gherkin as this language.
The goal is to be able to detect even more errors
than TDD, by targeting potential acceptance errors
too and make communication between parties smoother.
A set of tools are currently available
to write the specifications and match them with code functions,
such as Cucumber or SpecFlow.
A set of tools are built on top of Selenium to make this process
even faster by directly transforming the BDD specifications into
Some of these are JBehave, Capybara and Robot Framework.