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 OneInstancePerTestis intended primarily to serve as a supertrait forParallelTestExecutionand 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
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Abstract Value Members
-   abstract  def expectedTestCount(filter: Filter): IntThe total number of tests that are expected to run when this Suite'srunmethod is invoked.The total number of tests that are expected to run when this Suite'srunmethod is invoked.- filter
- a - Filterwith which to filter tests to count based on their tags
 - Definition Classes
- SuiteMixin
 
-   abstract  def nestedSuites: IndexedSeq[Suite]An immutable IndexedSeqof thisSuiteMixinobject's nestedSuites.An immutable IndexedSeqof thisSuiteMixinobject's nestedSuites. If thisSuiteMixincontains no nestedSuites, 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): StatusRuns 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.,- Noneacts like a wildcard that means execute all relevant tests in this- Suite.
- args
- the - Argsfor this run
- returns
- a - Statusobject 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
- NullArgumentExceptionif any passed parameter is- null.
 
-   abstract  def runNestedSuites(args: Args): StatusRuns zero to many of this suite's nested suites. Runs zero to many of this suite's nested suites. - args
- the - Argsfor this run
- returns
- a - Statusobject that indicates when all nested suites started by this method have completed, and whether or not a failure occurred.
 - Attributes
- protected
- Definition Classes
- SuiteMixin
- Exceptions thrown
- NullArgumentExceptionif- argsis- null.
 
-   abstract  def suiteId: StringA string ID for this Suitethat is intended to be unique among all suites reported during a run.A string ID for this Suitethat 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 - Suiteobject's ID.
 - Definition Classes
- SuiteMixin
 
-   abstract  def suiteName: StringA 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 runNestedSuitescalls this method to obtain a name forReports to pass to thesuiteStarting,suiteCompleted, andsuiteAbortedmethods of theReporter.- returns
- this - Suiteobject's suite name.
 - Definition Classes
- SuiteMixin
 
-   abstract  def tags: Map[String, Set[String]]A Mapwhose keys areStringnames of tagged tests and whose associated values are theSetof tag names for the test.A Mapwhose keys areStringnames of tagged tests and whose associated values are theSetof tag names for the test. If a test has no associated tags, its name does not appear as a key in the returnedMap. If thisSuitecontains 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 Setas 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): TestDataProvides a TestDatainstance for the passed test name, given the passed config map.Provides a TestDatainstance for the passed test name, given the passed config map.This method is used to obtain a TestDatainstance to pass towithFixture(NoArgTest)andwithFixture(OneArgTest)and thebeforeEachandafterEachmethods of traitBeforeAndAfterEach.- testName
- the name of the test for which to return a - TestDatainstance
- theConfigMap
- the config map to include in the returned - TestData
- returns
- a - TestDatainstance for the specified test, which includes the specified config map
 - Definition Classes
- SuiteMixin
 
-   abstract  def testNames: Set[String]A Setof test names.A Setof test names. If thisSuitecontains no tests, this method returns an emptySet.Although subclass and subtrait implementations of this method may return a Setwhose iterator producesStringtest 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: StringThe styleNamelifecycle method has been deprecated and will be removed in a future version of ScalaTest.The styleNamelifecycle 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
-   final  def !=(arg0: Any): Boolean- Definition Classes
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-   final  def ##(): Int- Definition Classes
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-   final  def ==(arg0: Any): Boolean- Definition Classes
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-   final  def asInstanceOf[T0]: T0- Definition Classes
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-    def clone(): AnyRef- Attributes
- protected[java.lang]
- Definition Classes
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- @throws(classOf[java.lang.CloneNotSupportedException]) @native()
 
-   final  def eq(arg0: AnyRef): Boolean- Definition Classes
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-    def equals(arg0: AnyRef): Boolean- Definition Classes
- AnyRef → Any
 
-    def finalize(): Unit- Attributes
- protected[java.lang]
- Definition Classes
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- @throws(classOf[java.lang.Throwable])
 
-   final  def getClass(): Class[_ <: AnyRef]- Definition Classes
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-    def hashCode(): Int- Definition Classes
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-   final  def isInstanceOf[T0]: Boolean- Definition Classes
- Any
 
-   final  def ne(arg0: AnyRef): Boolean- Definition Classes
- AnyRef
 
-    def newInstance: Suite with OneInstancePerTestConstruct a new instance of this Suite.Construct a new instance of this Suite.This trait's implementation of runTestsinvokes this method to create a new instance of thisSuitefor 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'sRunneraSuiteneeds a public, no-arg constructor. However, this will not be true of anySuitedefined 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 aSuiteclass is explicitly defined without a public, no-arg constructor, you will need to override this method to construct a new instance of theSuitein some other way.Here's an example of how you could override newInstanceto 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 } }
-   final  def notify(): Unit- Definition Classes
- AnyRef
- Annotations
- @native()
 
-   final  def notifyAll(): Unit- Definition Classes
- AnyRef
- Annotations
- @native()
 
-    def runTest(testName: String, args: Args): StatusModifies the behavior of super.runTestto facilitate running each test in its own instance of thisSuite's class.Modifies the behavior of super.runTestto facilitate running each test in its own instance of thisSuite's class.This trait's implementation of runTestuses therunTestInNewInstanceflag of the passedArgsobject to determine whether this instance is the general instance responsible for running all tests in the suite (runTestInNewInstanceistrue), or a test-specific instance responsible for running just one test (runTestInNewInstanceisfalse). Note that theseBooleanvalues are reverse those used byrunTests, becauserunTestsalways inverts theBooleanvalue ofrunTestInNewInstancewhen invokingrunTest.If runTestInNewInstanceistrue, this trait's implementation of this method creates a new instance of this class (by invokingnewInstanceon itself), then invokesrunon the new instance, passing intestName, wrapped in aSome, andargsunchanged. (I.e., theArgsobject passed torunTestis forwarded as is torunon the new instance, including withrunTestInNewInstanceset.) If the invocation of eithernewInstanceon thisSuiteorrunon a newly created instance of thisSuitecompletes abruptly with an exception, then thisrunTestsmethod will complete abruptly with the same exception.If runTestInNewInstanceisfalse, this trait's implementation of this method simply invokessuper.runTest, passing along the sametestNameandargsobjects.- testName
- the name of one test to execute. 
- args
- the - Argsfor this run
- returns
- a - Statusobject that indicates when the test started by this method has completed, and whether or not it failed .
 - Attributes
- protected
- Definition Classes
- OneInstancePerTest → SuiteMixin
 
-    def runTests(testName: Option[String], args: Args): StatusModifies the behavior of super.runTeststo facilitate running each test in its own instance of thisSuite's class.Modifies the behavior of super.runTeststo facilitate running each test in its own instance of thisSuite's class.This trait's implementation of runTestuses therunTestInNewInstanceflag of the passedArgsobject to determine whether this instance is the general instance responsible for running all tests in the suite (runTestInNewInstanceisfalse), or a test-specific instance responsible for running just one test (runTestInNewInstanceistrue). Note that theseBooleanvalues are reverse those used byrunTest, becauserunTestsalways inverts theBooleanvalue ofrunTestInNewInstancewhen invokingrunTest.If runTestInNewInstanceisfalse, this trait's implementation of this method will invokesuper.runTests, passing alongtestNameandargs, but with therunTestInNewInstanceflag set totrue. By settingrunTestInNewInstancetotrue,runTestsis tellingrunTestto create a new instance to run each test.If runTestInNewInstanceistrue, this trait's implementation of this method will invokerunTestdirectly, passing intestName.getand theargsobject, with therunTestInNewInstanceflag set tofalse. By settingrunTestInNewInstancetofalse,runTestsis tellingrunTestthat this is the test-specific instance, so it should just run the specified test.- testName
- an optional name of one test to run. If - None, all relevant tests should be run. I.e.,- Noneacts like a wildcard that means run all relevant tests in this- Suite.
- args
- the - Argsfor this run
- returns
- a - Statusobject that indicates when all tests started by this method have completed, and whether or not a failure occurred.
 - Attributes
- protected
- Definition Classes
- OneInstancePerTest → SuiteMixin
- Exceptions thrown
- IllegalArgumentExceptionif- testNameis defined, but no test with the specified test name exists in this- Suite, or if- runTestInNewInstanceis- true, but- testNameis empty.- NullPointerExceptionif any of the passed parameters is- null.
 
-   final  def synchronized[T0](arg0: => T0): T0- Definition Classes
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-    def toString(): String- Definition Classes
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-   final  def wait(): Unit- Definition Classes
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- Annotations
- @throws(classOf[java.lang.InterruptedException])
 
-   final  def wait(arg0: Long, arg1: Int): Unit- Definition Classes
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- Annotations
- @throws(classOf[java.lang.InterruptedException])
 
-   final  def wait(arg0: Long): Unit- Definition Classes
- AnyRef
- Annotations
- @throws(classOf[java.lang.InterruptedException]) @native()