trait OneInstancePerTest extends SuiteMixin
Trait that facilitates a style of testing in which each test is run in its own instance of the suite class to isolate each test from the side effects of the other tests in the suite.
Recommended Usage: Trait OneInstancePerTest is intended primarily to serve as a supertrait for
ParallelTestExecution and the path traits, to
facilitate porting JUnit tests to ScalaTest, and to make it easy for users who prefer JUnit's approach to isolation to obtain similar
behavior in ScalaTest.
|
If you mix this trait into a Suite
, you can initialize shared reassignable
fixture variables as well as shared mutable fixture objects in the constructor of the
class. Because each test will run in its own instance of the class, each test will
get a fresh copy of the instance variables. This is the approach to test isolation taken,
for example, by the JUnit framework. OneInstancePerTest
can, therefore,
be handy when porting JUnit tests to ScalaTest.
Here's an example of OneInstancePerTest
being used in a FunSuite
:
import org.scalatest.FunSuite import org.scalatest.OneInstancePerTest import collection.mutable.ListBuffer
class MySuite extends FunSuite with OneInstancePerTest {
val builder = new StringBuilder("ScalaTest is ") val buffer = new ListBuffer[String]
test("easy") { builder.append("easy!") assert(builder.toString === "ScalaTest is easy!") assert(buffer.isEmpty) buffer += "sweet" }
test("fun") { builder.append("fun!") assert(builder.toString === "ScalaTest is fun!") assert(buffer.isEmpty) } }
OneInstancePerTest
is supertrait to ParallelTestExecution
, in which
running each test in its own instance is intended to make it easier to write suites of tests that run in parallel (by reducing the likelihood
of concurrency bugs in those suites.) OneInstancePerTest
is also supertrait to the path traits,
path.FunSpec
and path.FreeSpec
, to make it obvious
these traits run each test in a new, isolated instance.
For the details on how OneInstancePerTest
works, see the documentation for methods runTests
and runTest
,
which this trait overrides.
- Self Type
- OneInstancePerTest with Suite
- Source
- OneInstancePerTest.scala
- Alphabetic
- By Inheritance
- OneInstancePerTest
- SuiteMixin
- AnyRef
- Any
- Hide All
- Show All
- Public
- Protected
Abstract Value Members
- abstract def expectedTestCount(filter: Filter): Int
The total number of tests that are expected to run when this
Suite
'srun
method is invoked.The total number of tests that are expected to run when this
Suite
'srun
method is invoked.- filter
a
Filter
with which to filter tests to count based on their tags
- Definition Classes
- SuiteMixin
- abstract def nestedSuites: IndexedSeq[Suite]
An immutable
IndexedSeq
of thisSuiteMixin
object's nestedSuite
s.An immutable
IndexedSeq
of thisSuiteMixin
object's nestedSuite
s. If thisSuiteMixin
contains no nestedSuite
s, this method returns an emptyIndexedSeq
.- Definition Classes
- SuiteMixin
- abstract def rerunner: Option[String]
The fully qualified name of the class that can be used to rerun this suite.
The fully qualified name of the class that can be used to rerun this suite.
- Definition Classes
- SuiteMixin
- abstract def run(testName: Option[String], args: Args): Status
Runs this suite of tests.
Runs this suite of tests.
- testName
an optional name of one test to execute. If
None
, all relevant tests should be executed. I.e.,None
acts like a wildcard that means execute all relevant tests in thisSuite
.- args
the
Args
for this run- returns
a
Status
object that indicates when all tests and nested suites started by this method have completed, and whether or not a failure occurred.
- Definition Classes
- SuiteMixin
- Exceptions thrown
NullArgumentException
if any passed parameter isnull
.
- abstract def suiteId: String
A string ID for this
Suite
that is intended to be unique among all suites reported during a run.A string ID for this
Suite
that is intended to be unique among all suites reported during a run.The suite ID is intended to be unique, because ScalaTest does not enforce that it is unique. If it is not unique, then you may not be able to uniquely identify a particular test of a particular suite. This ability is used, for example, to dynamically tag tests as having failed in the previous run when rerunning only failed tests.
- returns
this
Suite
object's ID.
- Definition Classes
- SuiteMixin
- abstract def suiteName: String
A user-friendly suite name for this
Suite
.A user-friendly suite name for this
Suite
.This trait's implementation of this method returns the simple name of this object's class. This trait's implementation of
runNestedSuites
calls this method to obtain a name forReport
s to pass to thesuiteStarting
,suiteCompleted
, andsuiteAborted
methods of theReporter
.- returns
this
Suite
object's suite name.
- Definition Classes
- SuiteMixin
- abstract def tags: Map[String, Set[String]]
A
Map
whose keys areString
names of tagged tests and whose associated values are theSet
of tag names for the test.A
Map
whose keys areString
names of tagged tests and whose associated values are theSet
of tag names for the test. If a test has no associated tags, its name does not appear as a key in the returnedMap
. If thisSuite
contains no tests with tags, this method returns an emptyMap
.Subclasses may override this method to define and/or discover tags in a custom manner, but overriding method implementations should never return an empty
Set
as a value. If a test has no tags, its name should not appear as a key in the returnedMap
.- Definition Classes
- SuiteMixin
- abstract def testDataFor(testName: String, theConfigMap: ConfigMap): TestData
Provides a
TestData
instance for the passed test name, given the passed config map.Provides a
TestData
instance for the passed test name, given the passed config map.This method is used to obtain a
TestData
instance to pass towithFixture(NoArgTest)
andwithFixture(OneArgTest)
and thebeforeEach
andafterEach
methods of traitBeforeAndAfterEach
.- testName
the name of the test for which to return a
TestData
instance- theConfigMap
the config map to include in the returned
TestData
- returns
a
TestData
instance for the specified test, which includes the specified config map
- Definition Classes
- SuiteMixin
- abstract def testNames: Set[String]
A
Set
of test names.A
Set
of test names. If thisSuite
contains no tests, this method returns an emptySet
.Although subclass and subtrait implementations of this method may return a
Set
whose iterator producesString
test names in a well-defined order, the contract of this method does not required a defined order. Subclasses are free to implement this method and return test names in either a defined or undefined order.- Definition Classes
- SuiteMixin
- abstract val styleName: String
The
styleName
lifecycle method has been deprecated and will be removed in a future version of ScalaTest.The
styleName
lifecycle method has been deprecated and will be removed in a future version of ScalaTest.This method was used to support the chosen styles feature, which was deactivated in 3.1.0. The internal modularization of ScalaTest in 3.2.0 will replace chosen styles as the tool to encourage consistency across a project. We do not plan a replacement for
styleName
.- Definition Classes
- SuiteMixin
- Annotations
- @deprecated
- Deprecated
(Since version 3.1.0) The styleName lifecycle method has been deprecated and will be removed in a future version of ScalaTest with no replacement.
Concrete Value Members
- def newInstance: Suite with OneInstancePerTest
Construct a new instance of this
Suite
.Construct a new instance of this
Suite
.This trait's implementation of
runTests
invokes this method to create a new instance of thisSuite
for each test. This trait's implementation of this method uses reflection to callthis.getClass.newInstance
. This approach will succeed only if thisSuite
's class has a public, no-arg constructor. In most cases this is likely to be true, because to be instantiated by ScalaTest'sRunner
aSuite
needs a public, no-arg constructor. However, this will not be true of anySuite
defined as an inner class of another class or trait, because every constructor of an inner class type takes a reference to the enclosing instance. In such cases, and in cases where aSuite
class is explicitly defined without a public, no-arg constructor, you will need to override this method to construct a new instance of theSuite
in some other way.Here's an example of how you could override
newInstance
to construct a new instance of an inner class:import org.scalatest.Suite
class Outer { class InnerSuite extends Suite with OneInstancePerTest { def testOne() {} def testTwo() {} override def newInstance = new InnerSuite } }