org.scalatest.Spec

Trait that facilitates a “behavior-driven” style of development (BDD), in which tests are methods, optionally nested inside singleton objects defining textual scopes.

Recommended Usage: Trait Spec allows you to define tests as methods, which saves one generated class file per test compared to style traits that represent tests as functions. As a result, using Spec can be a good choice in large projects where class file generation is a concern as well as when generating tests programatically via a static code generator.

Here's an example Spec:

package org.scalatest.examples.spec

import org.scalatest.Spec

class SetSpec extends Spec {

  object `A Set` {
    object `when empty` {
      def `should have size 0` {
        assert(Set.empty.size === 0)
      }

      def `should produce NoSuchElementException when head is invoked` {
        intercept[NoSuchElementException] {
          Set.empty.head
        }
      }
    }
  }
}

A Spec can contain scopes and tests. You define a scope with a nested singleton object, and a test with a method. The names of both scope objects and test methods must be expressed in back ticks and contain at least one space character.

A space placed in backticks is encoded by the Scala compiler as $u0020, as illustrated here:

scala> def `an example` = ()
an$u0020example: Unit

Spec uses reflection to discover scope objects and test methods. During discovery, Spec will consider any nested singleton object whose name includes $u0020 a scope object, and any method whose name includes $u0020 a test method. It will ignore any singleton objects or methods that do not include a $u0020 character. Thus, Spec would not consider the following singleton object a scope object:

object `Set` { // Not discovered, because no space character
}

You can make such a scope discoverable by placing a space at the end, like this:

object `Set ` { // Discovered, because of the trailing space character
}

Rather than performing this discovery during construction, when instance variables used by scope objects may as yet be uninitialized, Spec performs discovery lazily, the first time a method needing the results of discovery is invoked. For example, methods run, runTests, tags, expectedTestCount, runTest, and testNames all ensure that scopes and tests have already been discovered prior to doing anything else. Discovery is performed, and the results recorded, only once for each Spec instance.

A scope names, or gives more information about, the subject (class or other entity) you are specifying and testing. In the previous example, `A Set` is the subject under specification and test. With each test name you provide a string (the test text) that specifies one bit of behavior of the subject, and a block of code (the body of the test method) that verifies that behavior.

When you execute a Spec, it will send Formatters in the events it sends to the Reporter. ScalaTest's built-in reporters will report these events in such a way that the output is easy to read as an informal specification of the subject being tested. For example, were you to run SetSpec from within the Scala interpreter:

scala> new SetSpec execute

You would see:

A Set
  when empty
  - should have size 0
  - should produce NoSuchElementException when head is invoked

Or, to run just the test named A Set when empty should have size 0, you could pass that test's name, or any unique substring of the name, such as "size 0" or even just "0". Here's an example:

scala> new SetSuite execute "size 0"
A Set
  when empty
  - should have size 0

You can also pass to execute a config map of key-value pairs, which will be passed down into suites and tests, as well as other parameters that configure the run itself. For more information on running in the Scala interpreter, see the documentation for Suite's execute method and the ScalaTest shell.

The execute method invokes a run method that takes two parameters. This run method, which actually executes the suite, will usually be invoked by a test runner, such as run, tools.Runner, a build tool, or an IDE.

The test methods shown in this example are parameterless. This is recommended even for test methods with obvious side effects. In production code you would normally declare no-arg, side-effecting methods as empty-paren methods, and call them with empty parentheses, to make it more obvious to readers of the code that they have a side effect. Whether or not a test method has a side effect, however, is a less important distinction than it is for methods in production code. Moreover, test methods are not normally invoked directly by client code, but rather through reflection by running the Suite that contains them, so a lack of parentheses on an invocation of a side-effecting test method would not normally appear in any client code. Given the empty parentheses do not add much value in the test methods case, the recommended style is to simply always leave them off.

Note: The approach of using backticks around test method names to make it easier to write descriptive test names was inspired by the SimpleSpec test framework, originally created by Coda Hale.

Ignored tests

To support the common use case of temporarily disabling a test in a Spec, with the good intention of resurrecting the test at a later time, you can annotate the test method with @Ignore. For example, to temporarily disable the test method with the name `should have size zero", just annotate it with @Ignore, like this:

package org.scalatest.examples.spec.ignore

import org.scalatest._

class SetSpec extends Spec {

  object `A Set` {
    object `when empty` {
      @Ignore def `should have size 0` {
        assert(Set.empty.size === 0)
      }

      def `should produce NoSuchElementException when head is invoked` {
        intercept[NoSuchElementException] {
          Set.empty.head
        }
      }
    }
  }
}

If you run this version of SetSpec with:

scala> new SetSpec execute

It will run only the second test and report that the first test was ignored:

A Set
  when empty
  - should have size 0 !!! IGNORED !!!
  - should produce NoSuchElementException when head is invoked

If you wish to temporarily ignore an entire suite of tests, you can annotate the test class with @Ignore, like this:

package org.scalatest.examples.spec.ignoreall

import org.scalatest._

@Ignore
class SetSpec extends Spec {

  object `A Set` {
    object `when empty` {
      def `should have size 0` {
        assert(Set.empty.size === 0)
      }

      def `should produce NoSuchElementException when head is invoked` {
        intercept[NoSuchElementException] {
          Set.empty.head
        }
      }
    }
  }
}

When you mark a test class with a tag annotation, ScalaTest will mark each test defined in that class with that tag. Thus, marking the SetSpec in the above example with the @Ignore tag annotation means that both tests in the class will be ignored. If you run the above SetSpec in the Scala interpreter, you'll see:

scala> new SetSpec execute
SetSpec:
A Set
  when empty
  - should have size 0 !!! IGNORED !!!
  - should produce NoSuchElementException when head is invoked !!! IGNORED !!!

Note that marking a test class as ignored won't prevent it from being discovered by ScalaTest. Ignored classes will be discovered and run, and all their tests will be reported as ignored. This is intended to keep the ignored class visible, to encourage the developers to eventually fix and “un-ignore” it. If you want to prevent a class from being discovered at all, use the DoNotDiscover annotation instead.

Informers

One of the objects to Spec's run method is a Reporter, which will collect and report information about the running suite of tests. Information about suites and tests that were run, whether tests succeeded or failed, and tests that were ignored will be passed to the Reporter as the suite runs. Most often the reporting done by default by Spec's methods will be sufficient, but occasionally you may wish to provide custom information to the Reporter from a test. For this purpose, an Informer that will forward information to the current Reporter is provided via the info parameterless method. You can pass the extra information to the Informer via one of its apply methods. The Informer will then pass the information to the Reporter via an InfoProvided event. Here's an example in which the Informer returned by info is used implicitly by the Given, When, and Then methods of trait GivenWhenThen:

package org.scalatest.examples.spec.info

import collection.mutable
import org.scalatest._

class SetSpec extends Spec with GivenWhenThen {

  object `A mutable Set` {
    def `should allow an element to be added` {
      Given("an empty mutable Set")
      val set = mutable.Set.empty[String]

      When("an element is added")
      set += "clarity"

      Then("the Set should have size 1")
      assert(set.size === 1)

      And("the Set should contain the added element")
      assert(set.contains("clarity"))

      info("That's all folks!")
    }
  }
}

If you run this Spec from the interpreter, you will see the following output:

scala> new SetSpec execute
A mutable Set
- should allow an element to be added
  + Given an empty mutable Set
  + When an element is added
  + Then the Set should have size 1
  + And the Set should contain the added element
  + That's all folks!

Pending tests

A pending test is one that has been given a name but is not yet implemented. The purpose of pending tests is to facilitate a style of testing in which documentation of behavior is sketched out before tests are written to verify that behavior (and often, before the behavior of the system being tested is itself implemented). Such sketches form a kind of specification of what tests and functionality to implement later.

To support this style of testing, a test can be given a name that specifies one bit of behavior required by the system being tested. The test can also include some code that sends more information about the behavior to the reporter when the tests run. At the end of the test, it can call method pending, which will cause it to complete abruptly with TestPendingException.

Because tests in ScalaTest can be designated as pending with TestPendingException, both the test name and any information sent to the reporter when running the test can appear in the report of a test run. (In other words, the code of a pending test is executed just like any other test.) However, because the test completes abruptly with TestPendingException, the test will be reported as pending, to indicate the actual test, and possibly the functionality, has not yet been implemented.

You can mark a test as pending in Spec by using "{ pending }" as the body of the test method, like this:

package org.scalatest.examples.spec.pending

import org.scalatest._

class SetSpec extends Spec {

  object `A Set` {
    object `when empty` {
      def `should have size 0` { pending }

      def `should produce NoSuchElementException when head is invoked` {
        intercept[NoSuchElementException] {
          Set.empty.head
        }
      }
    }
  }
}

(Note: “pending” is the body of the test. Thus the test contains just one statement, an invocation of the pending method, which throws TestPendingException.) If you run this version of SetSpec with:

scala> new SetSpec execute

It will run both tests, but report that test "should have size 0" is pending. You'll see:

A Set
  when empty
  - should have size 0 (pending)
  - should produce NoSuchElementException when head is invoked

Tagging tests

A Spec's tests may be classified into groups by tagging them with string names. When executing a Spec, groups of tests can optionally be included and/or excluded. In this trait's implementation, tags are indicated by annotations attached to the test method. To create a new tag type to use in Specs, simply define a new Java annotation that itself is annotated with the org.scalatest.TagAnnotation annotation. (Currently, for annotations to be visible in Scala programs via Java reflection, the annotations themselves must be written in Java.) For example, to create tags named SlowTest and DbTest, you would write in Java:

package org.scalatest.examples.spec.tagging;
import java.lang.annotation.*;
import org.scalatest.TagAnnotation;

@TagAnnotation
@Retention(RetentionPolicy.RUNTIME)
@Target({ElementType.METHOD, ElementType.TYPE})
public @interface SlowTest {}

@TagAnnotation
@Retention(RetentionPolicy.RUNTIME)
@Target({ElementType.METHOD, ElementType.TYPE})
public @interface DbTest {}

Given these annotations, you could tag Spec tests like this:

package org.scalatest.examples.spec.tagging

import org.scalatest.Spec

class SetSpec extends Spec {

  object `A Set` {
    object `when empty` {

      @SlowTest
      def `should have size 0` {
        assert(Set.empty.size === 0)
      }

      @SlowTest @DbTest
      def `should produce NoSuchElementException when head is invoked` {
        intercept[NoSuchElementException] {
          Set.empty.head
        }
      }
    }
  }
}

The run method takes a Filter, whose constructor takes an optional Set[String] called tagsToInclude and a Set[String] called tagsToExclude. If tagsToInclude is None, all tests will be run except those those with tags listed in the tagsToExclude Set. If tagsToInclude is defined, only tests with tags mentioned in the tagsToInclude set, and not mentioned in tagsToExclude, will be run.

A tag annotation also allows you to tag all the tests of a Spec in one stroke by annotating the class. For more information and examples, see the documentation for class Tag.

Shared fixtures

A test fixture is composed of the objects and other artifacts (files, sockets, database connections, etc.) tests use to do their work. When multiple tests need to work with the same fixtures, it is important to try and avoid duplicating the fixture code across those tests. The more code duplication you have in your tests, the greater drag the tests will have on refactoring the actual production code. ScalaTest recommends several techniques to eliminate such code duplication, and provides several traits to help. Each technique is geared towards helping you reduce code duplication without introducing instance vars, shared mutable objects, or other dependencies between tests. Eliminating shared mutable state across tests will make your test code easier to reason about and more amenable for parallel test execution.

The following sections describe these techniques, including explaining the recommended usage for each. But first, here's a table summarizing the options:

Technique	Recommended uses
get-fixture methods	Use when you need the same mutable fixture objects in multiple tests, and don't need to clean up after.
fixture-context objects	Use when you need different combinations of mutable fixture objects in different tests, and don't need to clean up after.
`OneInstancePerTest`	Use when porting JUnit tests to ScalaTest, or if you prefer JUnit's approach to test isolation: running each test in its own instance of the test class.
`withFixture(NoArgTest)`	Use when you need to perform side effects at the beginning and end of all or most tests, or want to stack traits that perform such side-effects.
loan-fixture methods	Use when different tests need different fixtures that must be cleaned up afterwords.
`withFixture(OneArgTest)`	Use when all or most tests need the same fixtures that must be cleaned up afterwords.
`BeforeAndAfter`	Use when you need to perform the same side-effects before and/or after tests, rather than at the beginning or end of tests.
`BeforeAndAfterEach`	Use when you want to stack traits that perform the same side-effects before and/or after tests, rather than at the beginning or end of tests.

Calling get-fixture methods

If you need to create the same mutable fixture objects in multiple tests, and don't need to clean them up after using them, the simplest approach is to write one or more get-fixture methods. A get-fixture method returns a new instance of a needed fixture object (or an holder object containing multiple fixture objects) each time it is called. You can call a get-fixture method at the beginning of each test that needs the fixture, storing the returned object or objects in local variables. Here's an example:

package org.scalatest.examples.spec.getfixture

import org.scalatest.Spec
import collection.mutable.ListBuffer

class ExampleSpec extends Spec {

  def fixture =
    new {
      val builder = new StringBuilder("ScalaTest is ")
      val buffer = new ListBuffer[String]
    }

  object `Testing ` {
    def `should be easy` {
      val f = fixture
      f.builder.append("easy!")
      assert(f.builder.toString === "ScalaTest is easy!")
      assert(f.buffer.isEmpty)
      f.buffer += "sweet"
    }

    def `should be fun` {
      val f = fixture
      f.builder.append("fun!")
      assert(f.builder.toString === "ScalaTest is fun!")
      assert(f.buffer.isEmpty)
    }
  }
}

The “f.” in front of each use of a fixture object provides a visual indication of which objects are part of the fixture, but if you prefer, you can import the the members with “import f._” and use the names directly.

If you need to configure fixture objects differently in different tests, you can pass configuration into the get-fixture method. For example, if you could pass in an initial value for a mutable fixture object as a parameter to the get-fixture method.

Instantiating fixture-context objects

An alternate technique that is especially useful when different tests need different combinations of fixture objects is to define the fixture objects as instance variables of fixture-context objects whose instantiation forms the body of tests. Like get-fixture methods, fixture-context objects are only appropriate if you don't need to clean up the fixtures after using them.

To use this technique, you define instance variables intialized with fixture objects in traits and/or classes, then in each test instantiate an object that contains just the fixture objects needed by the test. Traits allow you to mix together just the fixture objects needed by each test, whereas classes allow you to pass data in via a constructor to configure the fixture objects. Here's an example in which fixture objects are partitioned into two traits and each test just mixes together the traits it needs:

package org.scalatest.examples.spec.fixturecontext

import collection.mutable.ListBuffer
import org.scalatest.Spec

class ExampleSpec extends Spec {

  trait Builder {
    val builder = new StringBuilder("ScalaTest is ")
  }

  trait Buffer {
    val buffer = ListBuffer("ScalaTest", "is")
  }

  object `Testing ` {
    // This test needs the StringBuilder fixture
    def `should be productive` {
      new Builder {
        builder.append("productive!")
        assert(builder.toString === "ScalaTest is productive!")
      }
    }
  }

  object `Test code` {
    // This test needs the ListBuffer[String] fixture
    def `should be readable` {
      new Buffer {
        buffer += ("readable!")
        assert(buffer === List("ScalaTest", "is", "readable!"))
      }
    }

    // This test needs both the StringBuilder and ListBuffer
    def `should be clear and concise` {
      new Builder with Buffer {
        builder.append("clear!")
        buffer += ("concise!")
        assert(builder.toString === "ScalaTest is clear!")
        assert(buffer === List("ScalaTest", "is", "concise!"))
      }
    }
  }
}

Mixing in `OneInstancePerTest`

If every test method requires the same set of mutable fixture objects, and none require cleanup, one other approach you can take is make them simply vals and mix in trait OneInstancePerTest. If you mix in OneInstancePerTest, each test will be run in its own instance of the Suite, similar to the way JUnit tests are executed. Here's an example:

package org.scalatest.examples.spec.oneinstancepertest

import org.scalatest._
import collection.mutable.ListBuffer

class ExampleSpec extends Spec with OneInstancePerTest {

  val builder = new StringBuilder("ScalaTest is ")
  val buffer = new ListBuffer[String]

  object `Testing ` {
    def `should be easy` {
      builder.append("easy!")
      assert(builder.toString === "ScalaTest is easy!")
      assert(buffer.isEmpty)
      buffer += "sweet"
    }

    def `should be fun` {
      builder.append("fun!")
      assert(builder.toString === "ScalaTest is fun!")
      assert(buffer.isEmpty)
    }
  }
}

One way to think of OneInstancePerTest is that the entire Suite instance is like a fixture-context object, but with the difference that the test code doesn't run during construction as it does with the real fixture-context object technique. Because this trait emulates JUnit's manner of running tests, this trait can be helpful when porting JUnit tests to ScalaTest. The primary intended use of OneInstancePerTest is to serve as a supertrait for ParallelTestExecution and the path traits, but you can also mix it in directly to help you port JUnit tests to ScalaTest or if you prefer JUnit's approach to test isolation.

Overriding `withFixture(NoArgTest)`

Although the get-fixture method, fixture-context object, and OneInstancePerTest approaches take care of setting up a fixture at the beginning of each test, they don't address the problem of cleaning up a fixture at the end of the test. If you just need to perform a side-effect at the beginning or end of a test, and don't need to actually pass any fixture objects into the test, you can override withFixture(NoArgTest), one of ScalaTest's lifecycle methods defined in trait Suite.

Trait Suite's implementation of runTest passes a no-arg test function to withFixture(NoArgTest). It is withFixture's responsibility to invoke that test function. Suite's implementation of withFixture simply invokes the function, like this:

// Default implementation in trait Suite
protected def withFixture(test: NoArgTest) {
  test()
}

You can, therefore, override withFixture to perform setup before and/or cleanup after invoking the test function. If you have cleanup to perform, you should invoke the test function inside a try block and perform the cleanup in a finally clause, because the exception that causes a test to fail will propagate through withFixture back to runTest. (In other words, if the test fails, the test function invoked by withFixture will throw an exception.)

The withFixture method is designed to be stacked, and to enable this, you should always call the super implementation of withFixture, and let it invoke the test function rather than invoking the test function directly. In other words, instead of writing “test()”, you should write “super.withFixture(test)”, like this:

// Your implementation
override def withFixture(test: NoArgTest) {
  // Perform setup
  try super.withFixture(test) // Invoke the test function
  finally {
    // Perform cleanup
  }
}

Here's an example in which withFixture(NoArgTest) is used to take a snapshot of the working directory if a test fails, and and send that information to the reporter:

package org.scalatest.examples.spec.noargtest

import java.io.File
import org.scalatest.Spec

class ExampleSpec extends Spec {

  override def withFixture(test: NoArgTest) {

    try super.withFixture(test)
    catch {
      case e: Exception =>
        val currDir = new File(".")
        val fileNames = currDir.list()
        info("Dir snapshot: " + fileNames.mkString(", "))
        throw e
    }
  }

  object `This test` {
    def `should succeed` {
      assert(1 + 1 === 2)
    }

    def `should fail` {
      assert(1 + 1 === 3)
    }
  }
}

Running this version of ExampleSuite in the interpreter in a directory with two files, hello.txt and world.txt would give the following output:

scala> new ExampleSuite execute
ExampleSuite:
This test
- should fail *** FAILED ***
  2 did not equal 3 (<console>:33)
  + Dir snapshot: hello.txt, world.txt 
- should succeed

Note that the NoArgTest passed to withFixture, in addition to an apply method that executes the test, also includes the test name and the config map passed to runTest. Thus you can also use the test name and configuration objects in your withFixture implementation.

Calling loan-fixture methods

If you need to both pass a fixture object into a test and perform cleanup at the end of the test, you'll need to use the loan pattern. If different tests need different fixtures that require cleanup, you can implement the loan pattern directly by writing loan-fixture methods. A loan-fixture method takes a function whose body forms part or all of a test's code. It creates a fixture, passes it to the test code by invoking the function, then cleans up the fixture after the function returns.

The following example shows three tests that use two fixtures, a database and a file. Both require cleanup after, so each is provided via a loan-fixture method. (In this example, the database is simulated with a StringBuffer.)

package org.scalatest.examples.spec.loanfixture

import java.util.concurrent.ConcurrentHashMap

object DbServer { // Simulating a database server
  type Db = StringBuffer
  private val databases = new ConcurrentHashMap[String, Db]
  def createDb(name: String): Db = {
    val db = new StringBuffer
    databases.put(name, db)
    db
  }
  def removeDb(name: String) {
    databases.remove(name)
  }
}

import org.scalatest.Spec
import DbServer._
import java.util.UUID.randomUUID
import java.io._

class ExampleSpec extends Spec {

  def withDatabase(testCode: Db => Any) {
    val dbName = randomUUID.toString
    val db = createDb(dbName) // create the fixture
    try {
      db.append("ScalaTest is ") // perform setup
      testCode(db) // "loan" the fixture to the test
    }
    finally removeDb(dbName) // clean up the fixture
  }

  def withFile(testCode: (File, FileWriter) => Any) {
    val file = File.createTempFile("hello", "world") // create the fixture
    val writer = new FileWriter(file)
    try {
      writer.write("ScalaTest is ") // set up the fixture
      testCode(file, writer) // "loan" the fixture to the test
    }
    finally writer.close() // clean up the fixture
  }

  object `Testing ` {
    // This test needs the file fixture
    def `should be productive` {
      withFile { (file, writer) =>
        writer.write("productive!")
        writer.flush()
        assert(file.length === 24)
      }
    }
  }

  object `Test code` {
    // This test needs the database fixture
    def `should be readable` {
      withDatabase { db =>
        db.append("readable!")
        assert(db.toString === "ScalaTest is readable!")
      }
    }

    // This test needs both the file and the database
    def `should be clear and concise` {
      withDatabase { db =>
       withFile { (file, writer) => // loan-fixture methods compose
          db.append("clear!")
          writer.write("concise!")
          writer.flush()
          assert(db.toString === "ScalaTest is clear!")
          assert(file.length === 21)
        }
      }
    }
  }
}

As demonstrated by the last test, loan-fixture methods compose. Not only do loan-fixture methods allow you to give each test the fixture it needs, they allow you to give a test multiple fixtures and clean everything up afterwords.

Also demonstrated in this example is the technique of giving each test its own "fixture sandbox" to play in. When your fixtures involve external side-effects, like creating files or databases, it is a good idea to give each file or database a unique name as is done in this example. This keeps tests completely isolated, allowing you to run them in parallel if desired.

Overriding `withFixture(OneArgTest)`

If all or most tests need the same fixture, you can avoid some of the boilerplate of the loan-fixture method approach by using a fixture.Suite and overriding withFixture(OneArgTest). Each test in a fixture.Suite takes a fixture as a parameter, allowing you to pass the fixture into the test. You must indicate the type of the fixture parameter by specifying FixtureParam, and implement a withFixture method that takes a OneArgTest. This withFixture method is responsible for invoking the one-arg test function, so you can perform fixture set up before, and clean up after, invoking and passing the fixture into the test function.

To enable the stacking of traits that define withFixture(NoArgTest), it is a good idea to let withFixture(NoArgTest) invoke the test function instead of invoking the test function directly. To do so, you'll need to convert the OneArgTest to a NoArgTest. You can do that by passing the fixture object to the toNoArgTest method of OneArgTest. In other words, instead of writing “test(theFixture)”, you'd delegate responsibility for invoking the test function to the withFixture(NoArgTest) method of the same instance by writing:

withFixture(test.toNoArgTest(theFixture))

Here's a complete example:

package org.scalatest.examples.spec.oneargtest

import org.scalatest.fixture
import java.io._

class ExampleSpec extends fixture.Spec {

  case class F(file: File, writer: FileWriter)
  type FixtureParam = F

  def withFixture(test: OneArgTest) {

    // create the fixture
    val file = File.createTempFile("hello", "world")
    val writer = new FileWriter(file)
    val theFixture = F(file, writer)

    try {
      writer.write("ScalaTest is ") // set up the fixture
      withFixture(test.toNoArgTest(theFixture)) // "loan" the fixture to the test
    }
    finally writer.close() // clean up the fixture
  }

  object `Testing ` {
    def `should be easy` { f&#58; F =>
      f.writer.write("easy!")
      f.writer.flush()
      assert(f.file.length === 18)
    }

    def `should be fun` { f&#58; F =>
      f.writer.write("fun!")
      f.writer.flush()
      assert(f.file.length === 17)
    }
  }
}

In this example, the tests actually required two fixture objects, a File and a FileWriter. In such situations you can simply define the FixtureParam type to be a tuple containing the objects, or as is done in this example, a case class containing the objects. For more information on the withFixture(OneArgTest) technique, see the documentation for fixture.Suite.

Mixing in `BeforeAndAfter`

In all the shared fixture examples shown so far, the activities of creating, setting up, and cleaning up the fixture objects have been performed during the test. This means that if an exception occurs during any of these activities, it will be reported as a test failure. Sometimes, however, you may want setup to happen before the test starts, and cleanup after the test has completed, so that if an exception occurs during setup or cleanup, the entire suite aborts and no more tests are attempted. The simplest way to accomplish this in ScalaTest is to mix in trait BeforeAndAfter. With this trait you can denote a bit of code to run before each test with before and/or after each test each test with after, like this:

package org.scalatest.examples.spec.beforeandafter

import org.scalatest.Spec
import org.scalatest.BeforeAndAfter
import collection.mutable.ListBuffer

class ExampleSpec extends Spec with BeforeAndAfter {

  val builder = new StringBuilder
  val buffer = new ListBuffer[String]

  before {
    builder.append("ScalaTest is ")
  }

  after {
    builder.clear()
    buffer.clear()
  }

  object `Testing ` {
    def `should be easy` {
      builder.append("easy!")
      assert(builder.toString === "ScalaTest is easy!")
      assert(buffer.isEmpty)
      buffer += "sweet"
    }

    def `should be fun` {
      builder.append("fun!")
      assert(builder.toString === "ScalaTest is fun!")
      assert(buffer.isEmpty)
    }
  }
}

Note that the only way before and after code can communicate with test code is via some side-effecting mechanism, commonly by reassigning instance vars or by changing the state of mutable objects held from instance vals (as in this example). If using instance vars or mutable objects held from instance vals you wouldn't be able to run tests in parallel in the same instance of the test class unless you synchronized access to the shared, mutable state. This is why ScalaTest's ParallelTestExecution trait extends OneInstancePerTest. By running each test in its own instance of the class, each test has its own copy of the instance variables, so you don't need to synchronize. If you mixed ParallelTestExecution into the ExampleSuite above, the tests would run in parallel just fine without any synchronization needed on the mutable StringBuilder and ListBuffer[String] objects.

Although BeforeAndAfter provides a minimal-boilerplate way to execute code before and after tests, it isn't designed to enable stackable traits, because the order of execution would be non-obvious. If you want to factor out before and after code that is common to multiple test suites, you should use trait BeforeAndAfterEach instead, as shown later in the next section, composing fixtures by stacking traits.

Composing fixtures by stacking traits

In larger projects, teams often end up with several different fixtures that test classes need in different combinations, and possibly initialized (and cleaned up) in different orders. A good way to accomplish this in ScalaTest is to factor the individual fixtures into traits that can be composed using the stackable trait pattern. This can be done, for example, by placing withFixture methods in several traits, each of which call super.withFixture. Here's an example in which the StringBuilder and ListBuffer[String] fixtures used in the previous examples have been factored out into two stackable fixture traits named Builder and Buffer:

package org.scalatest.examples.spec.composingwithfixture

import org.scalatest._
import collection.mutable.ListBuffer

trait Builder extends SuiteMixin { this: Suite =>

  val builder = new StringBuilder

  abstract override def withFixture(test: NoArgTest) {
    builder.append("ScalaTest is ")
    try super.withFixture(test) // To be stackable, must call super.withFixture
    finally builder.clear()
  }
}

trait Buffer extends SuiteMixin { this: Suite =>

  val buffer = new ListBuffer[String]

  abstract override def withFixture(test: NoArgTest) {
    try super.withFixture(test) // To be stackable, must call super.withFixture
    finally buffer.clear()
  }
}

class ExampleSpec extends Spec with Builder with Buffer {

  object `Testing ` {
    def `should be easy` {
      builder.append("easy!")
      assert(builder.toString === "ScalaTest is easy!")
      assert(buffer.isEmpty)
      buffer += "sweet"
    }

    def `should be fun` {
      builder.append("fun!")
      assert(builder.toString === "ScalaTest is fun!")
      assert(buffer.isEmpty)
      buffer += "clear"
    }
  }
}

By mixing in both the Builder and Buffer traits, ExampleSpec gets both fixtures, which will be initialized before each test and cleaned up after. The order the traits are mixed together determines the order of execution. In this case, Builder is “super” to Buffer. If you wanted Buffer to be “super” to Builder, you need only switch the order you mix them together, like this:

class Example2Spec extends Spec with Buffer with Builder

And if you only need one fixture you mix in only that trait:

class Example3Spec extends Spec with Builder

Another way to create stackable fixture traits is by extending the BeforeAndAfterEach and/or BeforeAndAfterAll traits. BeforeAndAfterEach has a beforeEach method that will be run before each test (like JUnit's setUp), and an afterEach method that will be run after (like JUnit's tearDown). Similarly, BeforeAndAfterAll has a beforeAll method that will be run before all tests, and an afterAll method that will be run after all tests. Here's what the previously shown example would look like if it were rewritten to use the BeforeAndAfterEach methods instead of withFixture:

package org.scalatest.examples.spec.composingbeforeandaftereach

import org.scalatest._
import org.scalatest.BeforeAndAfterEach
import collection.mutable.ListBuffer

trait Builder extends BeforeAndAfterEach { this: Suite =>

  val builder = new StringBuilder

  override def beforeEach() {
    builder.append("ScalaTest is ")
    super.beforeEach() // To be stackable, must call super.beforeEach
  }

  override def afterEach() {
    try super.afterEach() // To be stackable, must call super.afterEach
    finally builder.clear()
  }
}

trait Buffer extends BeforeAndAfterEach { this: Suite =>

  val buffer = new ListBuffer[String]

  override def afterEach() {
    try super.afterEach() // To be stackable, must call super.afterEach
    finally buffer.clear()
  }
}

class ExampleSpec extends Spec with Builder with Buffer {

  object `Testing ` {
    def `should be easy` {
      builder.append("easy!")
      assert(builder.toString === "ScalaTest is easy!")
      assert(buffer.isEmpty)
      buffer += "sweet"
    }

    def `should be fun` {
      builder.append("fun!")
      assert(builder.toString === "ScalaTest is fun!")
      assert(buffer.isEmpty)
      buffer += "clear"
    }
  }
}

To get the same ordering as withFixture, place your super.beforeEach call at the end of each beforeEach method, and the super.afterEach call at the beginning of each afterEach method, as shown in the previous example. It is a good idea to invoke super.afterEach in a try block and perform cleanup in a finally clause, as shown in the previous example, because this ensures the cleanup code is performed even if super.afterEach throws an exception.

The difference between stacking traits that extend BeforeAndAfterEach versus traits that implement withFixture is that setup and cleanup code happens before and after the test in BeforeAndAfterEach, but at the beginning and end of the test in withFixture. Thus if a withFixture method completes abruptly with an exception, it is considered a failed test. By contrast, if any of the beforeEach or afterEach methods of BeforeAndAfterEach complete abruptly, it is considered an aborted suite, which will result in a SuiteAborted event.

Shared tests

Because Spec represents tests as methods, you cannot share or otherwise dynamically generate tests. Instead, use static code generation if you want to generate tests in a Spec. In other words, write a program that statically generates the entire source file of a Spec subclass.

Self Type: Spec

Linear Supertypes

Suite, Serializable, AbstractSuite, Assertions, AnyRef, Any

Ordering

Alphabetic
By inheritance

Inherited

Hide All
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Spec
Suite
Serializable
AbstractSuite
Assertions
AnyRef
Any

Visibility

Public
All

Type Members

class Equalizer extends AnyRef

Class used via an implicit conversion to enable any two objects to be compared with === in assertions in tests.
trait NoArgTest extends () ⇒ Unit with TestData

A test function taking no arguments, which also provides a test name and config map.

Value Members

def != (arg0: AnyRef): Boolean

Attributes
final
Definition Classes
AnyRef
def != (arg0: Any): Boolean

Attributes
final
Definition Classes
Any
def ## (): Int

Attributes
final
Definition Classes
AnyRef → Any
def == (arg0: AnyRef): Boolean

Attributes
final
Definition Classes
AnyRef
def == (arg0: Any): Boolean

Attributes
final
Definition Classes
Any
def asInstanceOf [T0] : T0

Attributes
final
Definition Classes
Any
def assert (o: Option[String]): Unit

Assert that an Option[String] is None.
Assert that an Option[String] is None. If the condition is None, this method returns normally. Else, it throws TestFailedException with the String value of the Some included in the TestFailedException's detail message.
This form of assert is usually called in conjunction with an implicit conversion to Equalizer, using a === comparison, as in:
```
assert(a === b)
```
For more information on how this mechanism works, see the documentation for Equalizer.
o
the Option[String] to assert

Definition Classes
Assertions
def assert (o: Option[String], clue: Any): Unit

Assert that an Option[String] is None.
Assert that an Option[String] is None. If the condition is None, this method returns normally. Else, it throws TestFailedException with the String value of the Some, as well as the String obtained by invoking toString on the specified clue, included in the TestFailedException's detail message.
This form of assert is usually called in conjunction with an implicit conversion to Equalizer, using a === comparison, as in:
```
assert(a === b, "extra info reported if assertion fails")
```
For more information on how this mechanism works, see the documentation for Equalizer.
o
the Option[String] to assert
clue
An objects whose toString method returns a message to include in a failure report.

Definition Classes
Assertions
def assert (condition: Boolean, clue: Any): Unit

Assert that a boolean condition, described in String message, is true.
Assert that a boolean condition, described in String message, is true. If the condition is true, this method returns normally. Else, it throws TestFailedException with the String obtained by invoking toString on the specified clue as the exception's detail message.
condition
the boolean condition to assert
clue
An objects whose toString method returns a message to include in a failure report.

Definition Classes
Assertions
def assert (condition: Boolean): Unit

Assert that a boolean condition is true.
Assert that a boolean condition is true. If the condition is true, this method returns normally. Else, it throws TestFailedException.
condition
the boolean condition to assert

Definition Classes
Assertions
def assume (o: Option[String]): Unit

Assume that an Option[String] is None.
Assume that an Option[String] is None. If the condition is None, this method returns normally. Else, it throws TestCanceledException with the String value of the Some included in the TestCanceledException's detail message.
This form of assume is usually called in conjunction with an implicit conversion to Equalizer, using a === comparison, as in:
```
assert(a === b)
```
For more information on how this mechanism works, see the documentation for Equalizer.
o
the Option[String] to assert

Definition Classes
Assertions
def assume (o: Option[String], clue: Any): Unit

Assume that an Option[String] is None.
Assume that an Option[String] is None. If the condition is None, this method returns normally. Else, it throws TestCanceledException with the String value of the Some, as well as the String obtained by invoking toString on the specified clue, included in the TestCanceledException's detail message.
This form of assume is usually called in conjunction with an implicit conversion to Equalizer, using a === comparison, as in:
```
assume(a === b, "extra info reported if assertion fails")
```
For more information on how this mechanism works, see the documentation for Equalizer.
o
the Option[String] to assert
clue
An objects whose toString method returns a message to include in a failure report.

Definition Classes
Assertions
def assume (condition: Boolean, clue: Any): Unit

Assume that a boolean condition, described in String message, is true.
Assume that a boolean condition, described in String message, is true. If the condition is true, this method returns normally. Else, it throws TestCanceledException with the String obtained by invoking toString on the specified clue as the exception's detail message.
condition
the boolean condition to assume
clue
An objects whose toString method returns a message to include in a failure report.

Definition Classes
Assertions
def assume (condition: Boolean): Unit

Assume that a boolean condition is true.
Assume that a boolean condition is true. If the condition is true, this method returns normally. Else, it throws TestCanceledException.
condition
the boolean condition to assert

Definition Classes
Assertions
def cancel (cause: Throwable): Nothing

Throws TestCanceledException, with the passed Throwable cause, to indicate a test failed.
Throws TestCanceledException, with the passed Throwable cause, to indicate a test failed. The getMessage method of the thrown TestCanceledException will return cause.toString.
cause
a Throwable that indicates the cause of the cancellation.

Definition Classes
Assertions
def cancel (message: String, cause: Throwable): Nothing

Throws TestCanceledException, with the passed String message as the exception's detail message and Throwable cause, to indicate a test failed.
Throws TestCanceledException, with the passed String message as the exception's detail message and Throwable cause, to indicate a test failed.
message
A message describing the failure.
cause
A Throwable that indicates the cause of the failure.

Definition Classes
Assertions
def cancel (message: String): Nothing

Throws TestCanceledException, with the passed String message as the exception's detail message, to indicate a test was canceled.
Throws TestCanceledException, with the passed String message as the exception's detail message, to indicate a test was canceled.
message
A message describing the cancellation.

Definition Classes
Assertions
def cancel (): Nothing

Throws TestCanceledException to indicate a test was canceled.
Throws TestCanceledException to indicate a test was canceled.

Definition Classes
Assertions
def clone (): AnyRef

Attributes
protected[lang]
Definition Classes
AnyRef
Annotations
@throws()
implicit def convertToEqualizer (left: Any): Equalizer

Implicit conversion from Any to Equalizer, used to enable assertions with === comparisons.
Implicit conversion from Any to Equalizer, used to enable assertions with === comparisons.
For more information on this mechanism, see the documentation for Equalizer.
Because trait Suite mixes in Assertions, this implicit conversion will always be available by default in ScalaTest Suites. This is the only implicit conversion that is in scope by default in every ScalaTest Suite. Other implicit conversions offered by ScalaTest, such as those that support the matchers DSL or invokePrivate, must be explicitly invited into your test code, either by mixing in a trait or importing the members of its companion object. The reason ScalaTest requires you to invite in implicit conversions (with the exception of the implicit conversion for === operator) is because if one of ScalaTest's implicit conversions clashes with an implicit conversion used in the code you are trying to test, your program won't compile. Thus there is a chance that if you are ever trying to use a library or test some code that also offers an implicit conversion involving a === operator, you could run into the problem of a compiler error due to an ambiguous implicit conversion. If that happens, you can turn off the implicit conversion offered by this convertToEqualizer method simply by overriding the method in your Suite subclass, but not marking it as implicit:
```
// In your Suite subclass
override def convertToEqualizer(left: Any) = new Equalizer(left)
```
left
the object whose type to convert to Equalizer.

Attributes
implicit
Definition Classes
Assertions
def createCatchReporter (reporter: Reporter): WrapperCatchReporter

Attributes
protected[scalatest]
Definition Classes
Suite
def eq (arg0: AnyRef): Boolean

Attributes
final
Definition Classes
AnyRef
def equals (arg0: Any): Boolean

Definition Classes
AnyRef → Any
def execute : Unit

Executes this Suite, printing results to the standard output.
Executes this Suite, printing results to the standard output.
This method, which simply invokes the other overloaded form of execute with default parameter values, is intended for use only as a mini-DSL for the Scala interpreter. It allows you to execute a Suite in the interpreter with a minimum of finger typing:
```
scala> new SetSpec execute
An empty Set
- should have size 0
- should produce NoSuchElementException when head is invoked !!! IGNORED !!!
```
If you do ever want to invoke execute outside the Scala interpreter, it is best style to invoke it with empty parens to indicate it has a side effect, like this:
```
// Use empty parens form in regular code (outside the Scala interpreter)
(new ExampleSuite).execute()
```
Attributes
final
Definition Classes
Suite
def execute (testName: String = null, configMap: Map[String, Any] = Map(), color: Boolean = true, durations: Boolean = false, shortstacks: Boolean = false, fullstacks: Boolean = false, stats: Boolean = false): Unit

Executes one or more tests in this Suite, printing results to the standard output.
Executes one or more tests in this Suite, printing results to the standard output.
This method invokes run on itself, passing in values that can be configured via the parameters to this method, all of which have default values. This behavior is convenient when working with ScalaTest in the Scala interpreter. Here's a summary of this method's parameters and how you can use them:
The testName parameter
If you leave testName at its default value (of null), this method will pass None to the testName parameter of run, and as a result all the tests in this suite will be executed. If you specify a testName, this method will pass Some(testName) to run, and only that test will be run. Thus to run all tests in a suite from the Scala interpreter, you can write:
```
scala> new ExampleSuite execute
```
(The above syntax actually invokes the overloaded parameterless form of execute, which calls this form with its default parameter values.) To run just the test named "my favorite test" in a suite from the Scala interpreter, you would write:
```
scala> new ExampleSuite execute ("my favorite test")
```
Or:
```
scala> new ExampleSuite execute (testName = "my favorite test")
```
The configMap parameter
If you provide a value for the configMap parameter, this method will pass it to run. If not, the default value of an empty Map will be passed. For more information on how to use a config map to configure your test suites, see the config map section in the main documentation for this trait. Here's an example in which you configure a run with the name of an input file:
```
scala> new ExampleSuite execute (configMap = Map("inputFileName" -> "in.txt")
```
The color parameter
If you leave the color parameter unspecified, this method will configure the reporter it passes to run to print to the standard output in color (via ansi escape characters). If you don't want color output, specify false for color, like this:
```
scala> new ExampleSuite execute (color = false)
```
The durations parameter
If you leave the durations parameter unspecified, this method will configure the reporter it passes to run to not print durations for tests and suites to the standard output. If you want durations printed, specify true for durations, like this:
```
scala> new ExampleSuite execute (durations = true)
```
The shortstacks and fullstacks parameters
If you leave both the shortstacks and fullstacks parameters unspecified, this method will configure the reporter it passes to run to not print stack traces for failed tests if it has a stack depth that identifies the offending line of test code. If you prefer a short stack trace (10 to 15 stack frames) to be printed with any test failure, specify true for shortstacks:
```
scala> new ExampleSuite execute (shortstacks = true)
```
For full stack traces, set fullstacks to true:
```
scala> new ExampleSuite execute (fullstacks = true)
```
If you specify true for both shortstacks and fullstacks, you'll get full stack traces.
The stats parameter
If you leave the stats parameter unspecified, this method will not fire RunStarting and either RunCompleted or RunAborted events to the reporter it passes to run. If you specify true for stats, this method will fire the run events to the reporter, and the reporter will print the expected test count before the run, and various statistics after, including the number of suites completed and number of tests that succeeded, failed, were ignored or marked pending. Here's how you get the stats:
```
scala> new ExampleSuite execute (stats = true)
```
To summarize, this method will pass to run:
- testName - None if this method's testName parameter is left at its default value of null, else Some(testName).
- reporter - a reporter that prints to the standard output
- stopper - a Stopper whose apply method always returns false
- filter - a Filter constructed with None for tagsToInclude and Set() for tagsToExclude
- configMap - the configMap passed to this method
- distributor - None
- tracker - a new Tracker
Note: In ScalaTest, the terms "execute" and "run" basically mean the same thing and can be used interchangably. The reason this method isn't named run is that it takes advantage of default arguments, and you can't mix overloaded methods and default arguments in Scala. (If named run, this method would have the same name but different arguments than the main run method that takes seven arguments. Thus it would overload and couldn't be used with default argument values.)
Design note: This method has two "features" that may seem unidiomatic. First, the default value of testName is null. Normally in Scala the type of testName would be Option[String] and the default value would be None, as it is in this trait's run method. The null value is used here for two reasons. First, in ScalaTest 1.5, execute was changed from four overloaded methods to one method with default values, taking advantage of the default and named parameters feature introduced in Scala 2.8. To not break existing source code, testName needed to have type String, as it did in two of the overloaded execute methods prior to 1.5. The other reason is that execute has always been designed to be called primarily from an interpeter environment, such as the Scala REPL (Read-Evaluate-Print-Loop). In an interpreter environment, minimizing keystrokes is king. A String type with a null default value lets users type suite.execute("my test name") rather than suite.execute(Some("my test name")), saving several keystrokes.
The second non-idiomatic feature is that shortstacks and fullstacks are all lower case rather than camel case. This is done to be consistent with the Shell, which also uses those forms. The reason lower case is used in the Shell is to save keystrokes in an interpreter environment. Most Unix commands, for example, are all lower case, making them easier and quicker to type. In the ScalaTest Shell, methods like shortstacks, fullstacks, and nostats, etc., are designed to be all lower case so they feel more like shell commands than methods.
testName
the name of one test to run.
configMap
a Map of key-value pairs that can be used by the executing Suite of tests.
color
a boolean that configures whether output is printed in color
durations
a boolean that configures whether test and suite durations are printed to the standard output
shortstacks
a boolean that configures whether short stack traces should be printed for test failures
fullstacks
a boolean that configures whether full stack traces should be printed for test failures
stats
a boolean that configures whether test and suite statistics are printed to the standard output

Attributes
final
Definition Classes
Suite
def expectResult (expected: Any)(actual: Any): Unit

Expect that the value passed as expected equals the value passed as actual.
Expect that the value passed as expected equals the value passed as actual. If the actual value equals the expected value (as determined by ==), expectResult returns normally. Else, expect throws a TestFailedException whose detail message includes the expected and actual values.
expected
the expected value
actual
the actual value, which should equal the passed expected value

Definition Classes
Assertions
def expectResult (expected: Any, clue: Any)(actual: Any): Unit

Expect that the value passed as expected equals the value passed as actual.
Expect that the value passed as expected equals the value passed as actual. If the actual equals the expected (as determined by ==), expectResult returns normally. Else, if actual is not equal to expected, expectResult throws a TestFailedException whose detail message includes the expected and actual values, as well as the String obtained by invoking toString on the passed clue.
expected
the expected value
clue
An object whose toString method returns a message to include in a failure report.
actual
the actual value, which should equal the passed expected value

Definition Classes
Assertions
def expectedTestCount (filter: Filter): Int

The total number of tests that are expected to run when this Suite's run method is invoked.
The total number of tests that are expected to run when this Suite's run method is invoked.
This trait's implementation of this method returns the sum of:
- the size of the testNames List, minus the number of tests marked as ignored and any tests that are exluded by the passed Filter
- the sum of the values obtained by invoking expectedTestCount on every nested Suite contained in nestedSuites
filter
a Filter with which to filter tests to count based on their tags

Attributes
final
Definition Classes
Spec → Suite → AbstractSuite
def fail (cause: Throwable): Nothing

Throws TestFailedException, with the passed Throwable cause, to indicate a test failed.
Throws TestFailedException, with the passed Throwable cause, to indicate a test failed. The getMessage method of the thrown TestFailedException will return cause.toString.
cause
a Throwable that indicates the cause of the failure.

Definition Classes
Assertions
def fail (message: String, cause: Throwable): Nothing

Throws TestFailedException, with the passed String message as the exception's detail message and Throwable cause, to indicate a test failed.
Throws TestFailedException, with the passed String message as the exception's detail message and Throwable cause, to indicate a test failed.
message
A message describing the failure.
cause
A Throwable that indicates the cause of the failure.

Definition Classes
Assertions
def fail (message: String): Nothing

Throws TestFailedException, with the passed String message as the exception's detail message, to indicate a test failed.
Throws TestFailedException, with the passed String message as the exception's detail message, to indicate a test failed.
message
A message describing the failure.

Definition Classes
Assertions
def fail (): Nothing

Throws TestFailedException to indicate a test failed.
Throws TestFailedException to indicate a test failed.

Definition Classes
Assertions
def finalize (): Unit

Attributes
protected[lang]
Definition Classes
AnyRef
Annotations
@throws()
def getClass (): java.lang.Class[_]

Attributes
final
Definition Classes
AnyRef
def hashCode (): Int

Definition Classes
AnyRef → Any
implicit def info : Informer

Returns an Informer that during test execution will forward strings (and other objects) passed to its apply method to the current reporter.
Returns an Informer that during test execution will forward strings (and other objects) passed to its apply method to the current reporter. If invoked in a constructor, it will register the passed string for forwarding later during test execution. If invoked while this Spec is being executed, such as from inside a test function, it will forward the information to the current reporter immediately. If invoked at any other time, it will throw an exception. This method can be called safely by any thread.

Attributes
protected implicit
def intercept [T <: AnyRef] (f: ⇒ Any)(implicit manifest: Manifest[T]): T

Intercept and return an exception that's expected to be thrown by the passed function value.
Intercept and return an exception that's expected to be thrown by the passed function value. The thrown exception must be an instance of the type specified by the type parameter of this method. This method invokes the passed function. If the function throws an exception that's an instance of the specified type, this method returns that exception. Else, whether the passed function returns normally or completes abruptly with a different exception, this method throws TestFailedException.
Note that the type specified as this method's type parameter may represent any subtype of AnyRef, not just Throwable or one of its subclasses. In Scala, exceptions can be caught based on traits they implement, so it may at times make sense to specify a trait that the intercepted exception's class must mix in. If a class instance is passed for a type that could not possibly be used to catch an exception (such as String, for example), this method will complete abruptly with a TestFailedException.
f
the function value that should throw the expected exception
manifest
an implicit Manifest representing the type of the specified type parameter.
returns
the intercepted exception, if it is of the expected type

Definition Classes
Assertions
def isInstanceOf [T0] : Boolean

Attributes
final
Definition Classes
Any
implicit def markup : Documenter

Returns a Documenter that during test execution will forward strings passed to its apply method to the current reporter.
Returns a Documenter that during test execution will forward strings passed to its apply method to the current reporter. If invoked in a constructor, it will register the passed string for forwarding later during test execution. If invoked while this Spec is being executed, such as from inside a test function, it will forward the information to the current reporter immediately. If invoked at any other time, it will throw an exception. This method can be called safely by any thread.

Attributes
protected implicit
def ne (arg0: AnyRef): Boolean

Attributes
final
Definition Classes
AnyRef
def nestedSuites : IndexedSeq[Suite]

An immutable IndexedSeq of this Suite object's nested Suites.
An immutable IndexedSeq of this Suite object's nested Suites. If this Suite contains no nested Suites, this method returns an empty IndexedSeq. This trait's implementation of this method returns an empty List.

Definition Classes
Suite → AbstractSuite
def notify (): Unit

Attributes
final
Definition Classes
AnyRef
def notifyAll (): Unit

Attributes
final
Definition Classes
AnyRef
def pending : PendingNothing

Throws TestPendingException to indicate a test is pending.
Throws TestPendingException to indicate a test is pending.
A pending test is one that has been given a name but is not yet implemented. The purpose of pending tests is to facilitate a style of testing in which documentation of behavior is sketched out before tests are written to verify that behavior (and often, the before the behavior of the system being tested is itself implemented). Such sketches form a kind of specification of what tests and functionality to implement later.
To support this style of testing, a test can be given a name that specifies one bit of behavior required by the system being tested. The test can also include some code that sends more information about the behavior to the reporter when the tests run. At the end of the test, it can call method pending, which will cause it to complete abruptly with TestPendingException. Because tests in ScalaTest can be designated as pending with TestPendingException, both the test name and any information sent to the reporter when running the test can appear in the report of a test run. (In other words, the code of a pending test is executed just like any other test.) However, because the test completes abruptly with TestPendingException, the test will be reported as pending, to indicate the actual test, and possibly the functionality it is intended to test, has not yet been implemented.
Note: This method always completes abruptly with a TestPendingException. Thus it always has a side effect. Methods with side effects are usually invoked with parentheses, as in pending(). This method is defined as a parameterless method, in flagrant contradiction to recommended Scala style, because it forms a kind of DSL for pending tests. It enables tests in suites such as FunSuite or FunSpec to be denoted by placing "(pending)" after the test name, as in:
```
test("that style rules are not laws") (pending)
```
Readers of the code see "pending" in parentheses, which looks like a little note attached to the test name to indicate it is pending. Whereas "(pending()) looks more like a method call, "(pending)" lets readers stay at a higher level, forgetting how it is implemented and just focusing on the intent of the programmer who wrote the code.
Definition Classes
Suite
def pendingUntilFixed (f: ⇒ Unit): Unit

Execute the passed block of code, and if it completes abruptly, throw TestPendingException, else throw TestFailedException.
Execute the passed block of code, and if it completes abruptly, throw TestPendingException, else throw TestFailedException.
This method can be used to temporarily change a failing test into a pending test in such a way that it will automatically turn back into a failing test once the problem originally causing the test to fail has been fixed. At that point, you need only remove the pendingUntilFixed call. In other words, a pendingUntilFixed surrounding a block of code that isn't broken is treated as a test failure. The motivation for this behavior is to encourage people to remove pendingUntilFixed calls when there are no longer needed.
This method facilitates a style of testing in which tests are written before the code they test. Sometimes you may encounter a test failure that requires more functionality than you want to tackle without writing more tests. In this case you can mark the bit of test code causing the failure with pendingUntilFixed. You can then write more tests and functionality that eventually will get your production code to a point where the original test won't fail anymore. At this point the code block marked with pendingUntilFixed will no longer throw an exception (because the problem has been fixed). This will in turn cause pendingUntilFixed to throw TestFailedException with a detail message explaining you need to go back and remove the pendingUntilFixed call as the problem orginally causing your test code to fail has been fixed.
f
a block of code, which if it completes abruptly, should trigger a TestPendingException

Definition Classes
Suite
def rerunner : Option[String]

The fully qualified class name of the rerunner to rerun this suite.
The fully qualified class name of the rerunner to rerun this suite. This implementation will look at this.getClass and see if it is either an accessible Suite, or it has a WrapWith annotation. If so, it returns the fully qualified class name wrapped in a Some, or else it returns None.

Definition Classes
Suite → AbstractSuite
def run (testName: Option[String], args: Args): Status

Runs this suite of tests.
Runs this suite of tests.
If testName is None, this trait's implementation of this method calls these two methods on this object in this order:
- runNestedSuites(report, stopper, tagsToInclude, tagsToExclude, configMap, distributor)
- runTests(testName, report, stopper, tagsToInclude, tagsToExclude, configMap)
If testName is defined, then this trait's implementation of this method calls runTests, but does not call runNestedSuites. This behavior is part of the contract of this method. Subclasses that override run must take care not to call runNestedSuites if testName is defined. (The OneInstancePerTest trait depends on this behavior, for example.)
Subclasses and subtraits that override this run method can implement them without invoking either the runTests or runNestedSuites methods, which are invoked by this trait's implementation of this method. It is recommended, but not required, that subclasses and subtraits that override run in a way that does not invoke runNestedSuites also override runNestedSuites and make it final. Similarly it is recommended, but not required, that subclasses and subtraits that override run in a way that does not invoke runTests also override runTests (and runTest, which this trait's implementation of runTests calls) and make it final. The implementation of these final methods can either invoke the superclass implementation of the method, or throw an UnsupportedOperationException if appropriate. The reason for this recommendation is that ScalaTest includes several traits that override these methods to allow behavior to be mixed into a Suite. For example, trait BeforeAndAfterEach overrides runTestss. In a Suite subclass that no longer invokes runTests from run, the BeforeAndAfterEach trait is not applicable. Mixing it in would have no effect. By making runTests final in such a Suite subtrait, you make the attempt to mix BeforeAndAfterEach into a subclass of your subtrait a compiler error. (It would fail to compile with a complaint that BeforeAndAfterEach is trying to override runTests, which is a final method in your trait.)
testName
an optional name of one test to run. If None, all relevant tests should be run. I.e., None acts like a wildcard that means run all relevant tests in this Suite.
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
Spec → Suite → AbstractSuite
def run (testName: Option[String], reporter: Reporter, stopper: Stopper, filter: Filter, configMap: Map[String, Any], distributor: Option[Distributor], tracker: Tracker): Status

This overloaded form of run has been deprecated and will be removed in a future version of ScalaTest. Please use the run method that takes two parameters instead.
This overloaded form of run has been deprecated and will be removed in a future version of ScalaTest. Please use the run method that takes two parameters instead.
This final implementation of this method constructs a Args instance from the passed reporter, stopper, filter, configMap, distributor, and tracker, and invokes the overloaded run method that takes two parameters, passing in the specified testName and the newly constructed Args. This method implementation enables existing code that called into the old run method to continue to work during the deprecation cycle. Subclasses and subtraits that overrode this method, however, will need to be changed to use the new two-parameter form instead.
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 this Suite.
reporter
the Reporter to which results will be reported
stopper
the Stopper that will be consulted to determine whether to stop execution early.
filter
a Filter with which to filter tests based on their tags
configMap
a Map of key-value pairs that can be used by the executing Suite of tests.
distributor
an optional Distributor, into which to put nested Suites to be executed by another entity, such as concurrently by a pool of threads. If None, nested Suites will be executed sequentially.
tracker
a Tracker tracking Ordinals being fired by the current thread.

Attributes
final
Definition Classes
AbstractSuite
def runNestedSuites (args: Args): Status

Run zero to many of this Suite's nested Suites.
Run zero to many of this Suite's nested Suites.
If the passed distributor is None, this trait's implementation of this method invokes run on each nested Suite in the List obtained by invoking nestedSuites. If a nested Suite's run method completes abruptly with an exception, this trait's implementation of this method reports that the Suite aborted and attempts to run the next nested Suite. If the passed distributor is defined, this trait's implementation puts each nested Suite into the Distributor contained in the Some, in the order in which the Suites appear in the List returned by nestedSuites, passing in a new Tracker obtained by invoking nextTracker on the Tracker passed to this method.
Implementations of this method are responsible for ensuring SuiteStarting events are fired to the Reporter before executing any nested Suite, and either SuiteCompleted or SuiteAborted after executing any nested Suite.
args
the Args for this run
returns
a Status object that indicates when all nested suites started by this method have completed, and whether or not a failure occurred.

Attributes
protected
Definition Classes
Suite → AbstractSuite
def runTest (testName: String, args: Args): Status

Run a test.
Run a test. This trait's implementation runs the test registered with the name specified by testName. Each test's name is a concatenation of the text of all describers surrounding a test, from outside in, and the test's spec text, with one space placed between each item. (See the documenation for testNames for an example.)
testName
the name of one test to execute.
args
the Args for this run
returns
a Status object that indicates when the test started by this method has completed, and whether or not it failed .

Attributes
protected
Definition Classes
Spec → Suite → AbstractSuite
def runTests (testName: Option[String], args: Args): Status

Run zero to many of this Spec's tests.
Run zero to many of this Spec's tests.
testName
an optional name of one test to run. If None, all relevant tests should be run. I.e., None acts like a wildcard that means run all relevant tests in this Suite.
args
the Args for this run
returns
a Status object that indicates when all tests started by this method have completed, and whether or not a failure occurred.

Attributes
protected
Definition Classes
Spec → Suite → AbstractSuite
val styleName : String

Suite style name.
Suite style name.

Attributes
final
Definition Classes
Spec → Suite → AbstractSuite
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.
This trait's implementation of this method returns the fully qualified name of this object's class. Each suite reported during a run will commonly be an instance of a different Suite class, and in such cases, this default implementation of this method will suffice. However, in special cases you may need to override this method to ensure it is unique for each reported suite. For example, if you write a Suite subclass that reads in a file whose name is passed to its constructor and dynamically creates a suite of tests based on the information in that file, you will likely need to override this method in your Suite subclass, perhaps by appending the pathname of the file to the fully qualified class name. That way if you run a suite of tests based on a directory full of these files, you'll have unique suite IDs for each reported suite.
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
Suite
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 for Reports to pass to the suiteStarting, suiteCompleted, and suiteAborted methods of the Reporter.
returns
this Suite object's suite name.

Definition Classes
Suite
def synchronized [T0] (arg0: ⇒ T0): T0

Attributes
final
Definition Classes
AnyRef
def tags : Map[String, Set[String]]

A Map whose keys are String tag names to which tests in this Spec belong, and values the Set of test names that belong to each tag.
A Map whose keys are String tag names to which tests in this Spec belong, and values the Set of test names that belong to each tag. If this Spec contains no tags, this method returns an empty Map.
This trait's implementation returns tags that were passed as strings contained in Tag objects passed to methods test and ignore.
In addition, this trait's implementation will also auto-tag tests with class level annotations. For example, if you annotate @Ignore at the class level, all test methods in the class will be auto-annotated with @Ignore.

Definition Classes
Spec → Suite → AbstractSuite
def testDataFor (testName: String, theConfigMap: Map[String, Any] = Map.empty): 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 to withFixture(NoArgTest) and withFixture(OneArgTest) and the beforeEach and afterEach methods of trait BeforeAndAfterEach.
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
Spec → Suite
def testNames : Set[String]

An immutable Set of test names.
An immutable Set of test names. If this Spec contains no tests, this method returns an empty Set.
This trait's implementation of this method will return a set that contains the names of all registered tests. The set's iterator will return those names in the order in which the tests were registered. Each test's name is composed of the concatenation of the text of each surrounding describer, in order from outside in, and the text of the example itself, with all components separated by a space. For example, consider this Spec:
```
import org.scalatest.Spec

class StackSpec extends Spec {
  object `A Stack` {
    object `(when not empty)` {
      def `must allow me to pop` {}
    }
    object `(when not full)` {
      def `must allow me to push` {}
    }
  }
}
```
Invoking testNames on this Spec will yield a set that contains the following two test name strings:
```
"A Stack (when not empty) must allow me to pop"
"A Stack (when not full) must allow me to push"
```
Definition Classes
Spec → Suite → AbstractSuite
def toString (): String

Definition Classes
AnyRef → Any
def wait (): Unit

Attributes
final
Definition Classes
AnyRef
Annotations
@throws()
def wait (arg0: Long, arg1: Int): Unit

Attributes
final
Definition Classes
AnyRef
Annotations
@throws()
def wait (arg0: Long): Unit

Attributes
final
Definition Classes
AnyRef
Annotations
@throws()
def withClue [T] (clue: Any)(fun: ⇒ T): T

Executes the block of code passed as the second parameter, and, if it completes abruptly with a ModifiableMessage exception, prepends the "clue" string passed as the first parameter to the beginning of the detail message of that thrown exception, then rethrows it.
Executes the block of code passed as the second parameter, and, if it completes abruptly with a ModifiableMessage exception, prepends the "clue" string passed as the first parameter to the beginning of the detail message of that thrown exception, then rethrows it. If clue does not end in a white space character, one space will be added between it and the existing detail message (unless the detail message is not defined).
This method allows you to add more information about what went wrong that will be reported when a test fails. Here's an example:
```
withClue("(Employee's name was: " + employee.name + ")") {
  intercept[IllegalArgumentException] {
    employee.getTask(-1)
  }
}
```
If an invocation of intercept completed abruptly with an exception, the resulting message would be something like:
```
(Employee's name was Bob Jones) Expected IllegalArgumentException to be thrown, but no exception was thrown
```
Definition Classes
Assertions
def withFixture (test: NoArgTest): Unit

Run the passed test function in the context of a fixture established by this method.
Run the passed test function in the context of a fixture established by this method.
This method should set up the fixture needed by the tests of the current suite, invoke the test function, and if needed, perform any clean up needed after the test completes. Because the NoArgTest function passed to this method takes no parameters, preparing the fixture will require side effects, such as reassigning instance vars in this Suite or initializing a globally accessible external database. If you want to avoid reassigning instance vars you can use fixture.Suite.
This trait's implementation of runTest invokes this method for each test, passing in a NoArgTest whose apply method will execute the code of the test.
This trait's implementation of this method simply invokes the passed NoArgTest function.
test
the no-arg test function to run with a fixture

Attributes
protected
Definition Classes
Suite → AbstractSuite
def expect (expected: Any)(actual: Any): Unit

This expect method has been deprecated; Please use expectResult instead.
This expect method has been deprecated; Please use expectResult instead.
To get rid of the deprecation warning, simply replace expect with expectResult. The name expect will be used for a different purposes in a future version of ScalaTest.

Definition Classes
Assertions
Annotations
@deprecated
Deprecated
This expect method has been deprecated. Please replace all invocations of expect with an identical invocation of expectResult instead.
def expect (expected: Any, clue: Any)(actual: Any): Unit

This expect method has been deprecated; Please use expectResult instead.
This expect method has been deprecated; Please use expectResult instead.
To get rid of the deprecation warning, simply replace expect with expectResult. The name expect will be used for a different purposes in a future version of ScalaTest.

Definition Classes
Assertions
Annotations
@deprecated
Deprecated
This expect method has been deprecated. Please replace all invocations of expect with an identical invocation of expectResult instead.

Spec

trait Spec extends Suite

Ignored tests

Informers

Pending tests

Tagging tests

Shared fixtures

Calling get-fixture methods

Instantiating fixture-context objects

Mixing in OneInstancePerTest

Overriding withFixture(NoArgTest)

Calling loan-fixture methods

Overriding withFixture(OneArgTest)

Mixing in BeforeAndAfter

Composing fixtures by stacking traits

Shared tests

Type Members

class Equalizer extends AnyRef

trait NoArgTest extends () ⇒ Unit with TestData

Value Members

def != (arg0: AnyRef): Boolean

def != (arg0: Any): Boolean

def ## (): Int

def == (arg0: AnyRef): Boolean

def == (arg0: Any): Boolean

def asInstanceOf [T0] : T0

def assert (o: Option[String]): Unit

def assert (o: Option[String], clue: Any): Unit

def assert (condition: Boolean, clue: Any): Unit

def assert (condition: Boolean): Unit

def assume (o: Option[String]): Unit

def assume (o: Option[String], clue: Any): Unit

def assume (condition: Boolean, clue: Any): Unit

def assume (condition: Boolean): Unit

def cancel (cause: Throwable): Nothing

def cancel (message: String, cause: Throwable): Nothing

def cancel (message: String): Nothing

def cancel (): Nothing

def clone (): AnyRef

implicit def convertToEqualizer (left: Any): Equalizer

def createCatchReporter (reporter: Reporter): WrapperCatchReporter

def eq (arg0: AnyRef): Boolean

def equals (arg0: Any): Boolean

def execute : Unit

def execute (testName: String = null, configMap: Map[String, Any] = Map(), color: Boolean = true, durations: Boolean = false, shortstacks: Boolean = false, fullstacks: Boolean = false, stats: Boolean = false): Unit

def expectResult (expected: Any)(actual: Any): Unit

def expectResult (expected: Any, clue: Any)(actual: Any): Unit

def expectedTestCount (filter: Filter): Int

def fail (cause: Throwable): Nothing

def fail (message: String, cause: Throwable): Nothing

def fail (message: String): Nothing

def fail (): Nothing

def finalize (): Unit

def getClass (): java.lang.Class[_]

def hashCode (): Int

implicit def info : Informer

def intercept [T <: AnyRef] (f: ⇒ Any)(implicit manifest: Manifest[T]): T

def isInstanceOf [T0] : Boolean

implicit def markup : Documenter

def ne (arg0: AnyRef): Boolean

def nestedSuites : IndexedSeq[Suite]

def notify (): Unit

def notifyAll (): Unit

def pending : PendingNothing

def pendingUntilFixed (f: ⇒ Unit): Unit

def rerunner : Option[String]

def run (testName: Option[String], args: Args): Status

def run (testName: Option[String], reporter: Reporter, stopper: Stopper, filter: Filter, configMap: Map[String, Any], distributor: Option[Distributor], tracker: Tracker): Status

def runNestedSuites (args: Args): Status

def runTest (testName: String, args: Args): Status

def runTests (testName: Option[String], args: Args): Status

val styleName : String

def suiteId : String

def suiteName : String

def synchronized [T0] (arg0: ⇒ T0): T0

def tags : Map[String, Set[String]]

def testDataFor (testName: String, theConfigMap: Map[String, Any] = Map.empty): TestData

def testNames : Set[String]

def toString (): String

def wait (): Unit

Mixing in `OneInstancePerTest`

Overriding `withFixture(NoArgTest)`

Overriding `withFixture(OneArgTest)`

Mixing in `BeforeAndAfter`