GUI State Machine API

API for the creation and modification of incomplete state machines which represent the exploration of a GUI application. The states represent the GUI elements and the transitions represent the GUI actions.

This is a small code example of creating a new state machine, adding two states connected with a transition and saving the state machine:

import de.retest.guistatemachine.api.GuiStateMachineApi
import de.retest.guistatemachine.api.GuiStateMachineSerializer
import de.retest.recheck.ui.descriptors.SutState
import de.retest.surili.commons.actions.NavigateToAction
import de.retest.surili.commons.actions.ActionType

val action = new NavigateToAction("http://google.com")
val unexploredActionTypes = Set(ActionType.fromAction(action))

val stateMachine = GuiStateMachineApi().createStateMachine("test")

val currentSutState = new SutState(currentDescriptors)
val currentState = stateMachine.createState(currentSutState, unexploredActionTypes)

val nextSutState = new SutState(nextDescriptors)
val nextState = stateMachine.createState(nextSutState, unexploredActionTypes)

stateMachine.executeAction(currentState, action, nextState)

GuiStateMachineSerializer.javaObjectStream(stateMachine).save("mystatemachine.ser")
GuiStateMachineSerializer.gml(stateMachine).save("mystatemachine.gml")

State machines can be saved as and loaded from files using Java object serialization/deserialization. Besides, they can be saved as GML files which can be visualized by editors like yEd.

Build Credentials

Define the Nexus password in the environment variable RETEST_NEXUS_PASSWORD. Otherwise, the build will fail!

SBT Commands

• sbt compile to build the project manually.
• sbt assembly to create a standalone JAR which includes all dependencies including the Scala libraries. The standalone JAR is generated as target/scala-<scalaversion>/gui-state-machine-api-assembly-<version>.jar.
• sbt eclipse to generate a project for Eclipse.
• sbt test to execute all unit tests.
• sbt coverage to generate coverage data.
• sbt coverageReport to generate a HTML coverage report.
• sbt scalastyle to make a check with ScalaStyle.
• sbt doc to generate the scaladoc API documentation.
• sbt scalafmt to format the Scala source files with scalafmt.
• sbt 'release cross with-defaults' to create a release with a new version number which is added as tag. This command does also publish the artifacts.
• sbt publish publishes the artifacts in ReTest's Nexus. This command can be useful to publish SNAPSHOT versions.
• sbt publishM2 publishes the artifacts in the local Maven repository.

NFA for the Representation of GUI Behavior

A nondeterministic finite automaton (NFA) represents the states of the GUI during testing. The actions executed by the user on GUI elements are represented by transitions. If an action has not been executed yet from a state, it leads to the so-called unknown state s_?. The unknown state is a special state from which all actions could be executed. Whenever an action, which previously led to s_?, is being executed and then leads to a newly discovered state, the NFA has to be updated. The same action might lead from one single state to different states since the states do not capture the whole program behavior. This makes the finite automaton nondeterministic.

The NFA is based on the UI model from "Search-Based System Testing: High Coverage, No False Alarms" (section "4.5 UI Model"). Originally, it has been used together with a genetic algorithm for search-based system testing, where it served three purposes:

1. Population initialization: to give precedence to unexplored actions.
2. Mutation: to insert unexplored actions.
3. Mutation: to repair test cases which became invalid by the mutation.

Concurrency

The creation and modification of state machines should be thread-safe.