org.scalatest

# Suite

#### trait Suite extends Assertions with AbstractSuite

A suite of tests. A `Suite` instance encapsulates a conceptual suite (i.e., a collection) of tests.

This trait provides an interface that allows suites of tests to be run. Its implementation enables a default way of writing and executing tests. Subtraits and subclasses can override `Suite`'s methods to enable other ways of writing and executing tests. This trait's default approach allows tests to be defined as methods whose name starts with "`test`." This approach is easy to understand, and a good way for Scala beginners to start writing tests. More advanced Scala programmers may prefer to mix together other `Suite` subtraits defined in ScalaTest, or create their own, to write tests in the way they feel makes them most productive. Here's a quick overview of some of the options to help you get started:

For JUnit 3 users

If you are using JUnit 3 (version 3.8 or earlier releases) and you want to write JUnit 3 tests in Scala, look at `AssertionsForJUnit`, `ShouldMatchersForJUnit`, and `JUnit3Suite`.

For JUnit 4 users

If you are using JUnit 4 and you want to write JUnit 4 tests in Scala, look at `JUnitSuite`, and `JUnitRunner`. With `JUnitRunner`, you can use any of the traits described here and still run your tests with JUnit 4.

For TestNG users

If you are using TestNG and you want to write TestNG tests in Scala, look at `TestNGSuite`.

For high-level testing

If you want to write tests at a higher level than unit tests, such as integration tests, acceptance tests, or functional tests, check out `FeatureSpec`.

For unit testing

If you prefer a behavior-driven development (BDD) style, in which tests are combined with text that specifies the behavior being tested, look at `Spec`, `FlatSpec`, `FreeSpec`, and `WordSpec`. Otherwise, if you just want to write tests and don't want to combine testing with specifying, look at `FunSuite` or read on to learn how to write tests using this base trait, `Suite`.

To use this trait's approach to writing tests, simply create classes that extend `Suite` and define test methods. Test methods have names of the form `testX`, where `X` is some unique, hopefully meaningful, string. A test method must be public and can have any result type, but the most common result type is `Unit`. Here's an example:

    import org.scalatest.Suite

    class ExampleSuite extends Suite {

      def testAddition {
        val sum = 1 + 1
        assert(sum === 2)
      }

      def testSubtraction {
        val diff = 4 - 1
        assert(diff === 3)
      }
    }

You can run a `Suite` by invoking `execute` on it. This method, which prints test results to the standard output, is intended to serve as a convenient way to run tests from within the Scala interpreter. For example, to run `ExampleSuite` from within the Scala interpreter, you could write:

    scala> (new ExampleSuite).execute()

And you would see:

    ExampleSuite:
    - testAddition
    - testSubtraction

Or, to run just the `testAddition` method, you could write:

    scala> (new ExampleSuite).execute("testAddition")

And you would see:

    ExampleSuite:
    - testAddition

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 `execute` (below) and the ScalaTest shell.

The `execute` method invokes a `run` method takes seven parameters. This `run` method, which actually executes the suite, will usually be invoked by a test runner, such as `org.scalatest.tools.Runner` or an IDE. See the documentation for `Runner` for more details.

#### Assertions and `=``=``=`

Inside test methods in a `Suite`, you can write assertions by invoking `assert` and passing in a `Boolean` expression, such as:

    val left = 2
    val right = 1
    assert(left == right)

If the passed expression is `true`, `assert` will return normally. If `false`, `assert` will complete abruptly with a `TestFailedException`. This exception is usually not caught by the test method, which means the test method itself will complete abruptly by throwing the `TestFailedException`. Any test method that completes abruptly with an exception is considered a failed test. A test method that returns normally is considered a successful test.

If you pass a `Boolean` expression to `assert`, a failed assertion will be reported, but without reporting the left and right values. You can alternatively encode these values in a `String` passed as a second argument to `assert`, as in:

    val left = 2
    val right = 1
    assert(left == right, left + " did not equal " + right)

Using this form of `assert`, the failure report will include the left and right values, helping you debug the problem. However, ScalaTest provides the `===` operator to make this easier. (The `===` operator is defined in trait `Assertions` which trait `Suite` extends.) You use it like this:

    val left = 2
    val right = 1
    assert(left === right)

Because you use `===` here instead of `==`, the failure report will include the left and right values. For example, the detail message in the thrown `TestFailedException` from the `assert` shown previously will include, "2 did not equal 1". From this message you will know that the operand on the left had the value 2, and the operand on the right had the value 1.

If you're familiar with JUnit, you would use `===` in a ScalaTest `Suite` where you'd use `assertEquals` in a JUnit `TestCase`. The `===` operator is made possible by an implicit conversion from `Any` to `Equalizer`. If you're curious to understand the mechanics, see the documentation for `Equalizer` and the `convertToEqualizer` method.

#### Expected results

Although `===` provides a natural, readable extension to Scala's `assert` mechanism, as the operands become lengthy, the code becomes less readable. In addition, the `===` comparison doesn't distinguish between actual and expected values. The operands are just called `left` and `right`, because if one were named `expected` and the other `actual`, it would be difficult for people to remember which was which. To help with these limitations of assertions, `Suite` includes a method called `expect` that can be used as an alternative to `assert` with `===`. To use `expect`, you place the expected value in parentheses after `expect`, followed by curly braces containing code that should result in the expected value. For example:

    val a = 5
    val b = 2
    expect(2) {
      a - b
    }

In this case, the expected value is `2`, and the code being tested is `a - b`. This expectation will fail, and the detail message in the `TestFailedException` will read, "Expected 2, but got 3."

#### Intercepted exceptions

Sometimes you need to test whether a method throws an expected exception under certain circumstances, such as when invalid arguments are passed to the method. You can do this in the JUnit style, like this:

    val s = "hi"
    try {
      s.charAt(-1)
      fail()
    }
    catch {
      case _: IndexOutOfBoundsException => // Expected, so continue
    }

If `charAt` throws `IndexOutOfBoundsException` as expected, control will transfer to the catch case, which does nothing. If, however, `charAt` fails to throw an exception, the next statement, `fail()`, will be executed. The `fail` method always completes abruptly with a `TestFailedException`, thereby signaling a failed test.

To make this common use case easier to express and read, ScalaTest provides an `intercept` method. You use it like this:

    val s = "hi"
    intercept[IndexOutOfBoundsException] {
      s.charAt(-1)
    }

This code behaves much like the previous example. If `charAt` throws an instance of `IndexOutOfBoundsException`, `intercept` will return that exception. But if `charAt` completes normally, or throws a different exception, `intercept` will complete abruptly with a `TestFailedException`. The `intercept` method returns the caught exception so that you can inspect it further if you wish, for example, to ensure that data contained inside the exception has the expected values. Here's an example:

    val s = "hi"
    val caught =
      intercept[IndexOutOfBoundsException] {
        s.charAt(-1)
      }
    assert(caught.getMessage === "String index out of range: -1")

#### Using other assertions

ScalaTest also supports another style of assertions via its matchers DSL. By mixing in trait `ShouldMatchers`, you can write suites that look like:

    import org.scalatest.Suite
    import org.scalatest.matchers.ShouldMatchers

    class ExampleSuite extends Suite with ShouldMatchers {

      def testAddition {
        val sum = 1 + 1
        sum should equal (2)
      }

      def testSubtraction {
        val diff = 4 - 1
        diff should equal (3)
      }
    }

If you prefer the word "`must`" to the word "`should`," you can alternatively mix in trait `MustMatchers`.

If you are comfortable with assertion mechanisms from other test frameworks, chances are you can use them with ScalaTest. Any assertion mechanism that indicates a failure with an exception can be used as is with ScalaTest. For example, to use the `assertEquals` methods provided by JUnit or TestNG, simply import them and use them. (You will of course need to include the relevant JAR file for the framework whose assertions you want to use on either the classpath or runpath when you run your tests.) Here's an example in which JUnit's assertions are imported, then used within a ScalaTest suite:

    import org.scalatest.Suite
    import org.junit.Assert._

    class ExampleSuite extends Suite {

      def testAddition {
        val sum = 1 + 1
        assertEquals(2, sum)
      }

      def testSubtraction {
        val diff = 4 - 1
        assertEquals(3, diff)
      }
    }

#### Nested suites

A `Suite` can refer to a collection of other `Suite`s, which are called nested `Suite`s. Those nested `Suite`s can in turn have their own nested `Suite`s, and so on. Large test suites can be organized, therefore, as a tree of nested `Suite`s. This trait's `run` method, in addition to invoking its test methods, invokes `run` on each of its nested `Suite`s.

A `List` of a `Suite`'s nested `Suite`s can be obtained by invoking its `nestedSuites` method. If you wish to create a `Suite` that serves as a container for nested `Suite`s, whether or not it has test methods of its own, simply override `nestedSuites` to return a `List` of the nested `Suite`s. Because this is a common use case, ScalaTest provides a convenience `Suites` class, which takes a variable number of nested `Suite`s as constructor parameters. Here's an example:

    import org.scalatest.Suite
    import org.scalatest.Suites

    class ASuite extends Suite {
      def testA {}
    }
    class BSuite extends Suite {
      def testB {}
    }
    class CSuite extends Suite {
      def testC {}
    }

    class AlphabetSuite extends Suites(
      new ASuite,
      new BSuite,
      new CSuite
    )

If you now run `AlphabetSuite`:

    scala> (new AlphabetSuite).execute()

You will see reports printed to the standard output that indicate the nested suites—`ASuite`, `BSuite`, and `CSuite`—were run:

    AlphabetSuite:
    ASuite:
    - testA
    BSuite:
    - testB
    CSuite:
    - testC

Note that `Runner` can discover `Suite`s automatically, so you need not necessarily define nested `Suites` explicitly. See the documentation for `Runner` for more information.

#### The config map

In some cases you may need to pass information to a suite of tests. For example, perhaps a suite of tests needs to grab information from a file, and you want to be able to specify a different filename during different runs. You can accomplish this in ScalaTest by passing the filename in a config map of key-value pairs, which is passed to `run` as a `Map[String, Any]`. The values in the config map are called "config objects," because they can be used to configure suites, reporters, and tests.

You can specify a string config object is via the ScalaTest `Runner`, either via the command line or ScalaTest's ant task. (See the documentation for Runner for information on how to specify config objects on the command line.) The config map is passed to `run`, `runNestedSuites`, `runTests`, and `runTest`, so one way to access it in your suite is to override one of those methods. If you need to use the config map inside your tests, you can access it from the `NoArgTest` passed to `withFixture`, or the `OneArgTest` passed to `withFixture` in the traits in the `org.scalatest.fixture` package. (See the documentation for `FixtureSuite` for instructions on how to access the config map in tests.)

#### Ignored tests

Another common use case is that tests must be “temporarily” disabled, with the good intention of resurrecting the test at a later time. ScalaTest provides an `Ignore` annotation for this purpose. You use it like this:

    import org.scalatest.Suite
    import org.scalatest.Ignore

    class ExampleSuite extends Suite {

      def testAddition {
        val sum = 1 + 1
        assert(sum === 2)
      }

      @Ignore
      def testSubtraction {
        val diff = 4 - 1
        assert(diff === 3)
      }
    }

If you run this version of `ExampleSuite` with:

    scala> (new ExampleSuite).run()

It will run only `testAddition` and report that `testSubtraction` was ignored. You'll see:

    ExampleSuite:
    - testAddition
    - testSubtraction !!! IGNORED !!!

`Ignore` is implemented as a tag. The `Filter` class effectively adds `org.scalatest.Ignore` to the `tagsToExclude` `Set` if it not already in the `tagsToExclude` set passed to its primary constructor. The only difference between `org.scalatest.Ignore` and the tags you may define and exclude is that ScalaTest reports ignored tests to the `Reporter`. The reason ScalaTest reports ignored tests is to encourage ignored tests to be eventually fixed and added back into the active suite of tests.

#### 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 it is intended to test, has not yet been implemented.

Although pending tests may be used more often in specification-style suites, such as `org.scalatest.Spec`, you can also use it in `Suite`, like this:

    import org.scalatest.Suite

    class ExampleSuite extends Suite {

      def testAddition {
        val sum = 1 + 1
        assert(sum === 2)
      }

      def testSubtraction { pending }
    }

If you run this version of `ExampleSuite` with:

    scala> (new ExampleSuite).run()

It will run both tests but report that `testSubtraction` is pending. You'll see:

    ExampleSuite:
    - testAddition
    - testSubtraction (pending)

#### Informers

One of the parameters to `run` 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 `Suite`'s methods will be sufficient, but occasionally you may wish to provide custom information to the `Reporter` from a test method. For this purpose, you can optionally include an `Informer` parameter in a test method, and then pass the extra information to the `Informer` via its `apply` method. The `Informer` will then pass the information to the `Reporter` by sending an `InfoProvided` event. Here's an example:

    import org.scalatest._

    class ExampleSuite extends Suite {

      def testAddition(info: Informer) {
        assert(1 + 1 === 2)
        info("Addition seems to work")
      }
    }

If you run this `Suite` from the interpreter, you will see the message included in the printed report:

    scala> (new ExampleSuite).run()
    ExampleSuite:
    - testAddition(Informer)
      + Addition seems to work

#### Executing suites in parallel

The `run` method takes as one of its parameters an optional `Distributor`. If a `Distributor` is passed in, this trait's implementation of `run` puts its nested `Suite`s into the distributor rather than executing them directly. The caller of `run` is responsible for ensuring that some entity runs the `Suite`s placed into the distributor. The `-c` command line parameter to `Runner`, for example, will cause `Suite`s put into the `Distributor` to be run in parallel via a pool of threads.

#### Tagging tests

A `Suite`'s tests may be classified into groups by tagging them with string names. When executing a `Suite`, 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 `Suite`s, 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 a tag named `SlowAsMolasses`, to use to mark slow tests, you would write in Java:

Because of a Scaladoc bug in Scala 2.8, I had to put a space after the at sign in one the target annotation example below. If you want to copy and paste from this example, you'll need to remove the space by hand. - Bill Venners

    import java.lang.annotation.*;
    import org.scalatest.TagAnnotation

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

Given this new annotation, you could place a `Suite` test method into the `SlowAsMolasses` group (i.e., tag it as being `SlowAsMolasses`) like this:

    @SlowAsMolasses
    def testSleeping { sleep(1000000) }

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 belonging to tags listed in the `tagsToExclude` `Set`. If `tagsToInclude` is defined, only tests belonging to tags mentioned in the `tagsToInclude` set, and not mentioned in `tagsToExclude`, will be run.

#### Shared fixtures

A test fixture is objects or other artifacts (such as files, sockets, database connections, etc.) used by tests to do their work. If a fixture is used by only one test method, then the definitions of the fixture objects can be local to the method, such as the objects assigned to `sum` and `diff` in the previous `ExampleSuite` examples. If multiple methods need to share an immutable fixture, one approach is to assign them to instance variables.

In some cases, however, shared mutable fixture objects may be changed by test methods such that they need to be recreated or reinitialized before each test. Shared resources such as files or database connections may also need to be created and initialized before, and cleaned up after, each test. JUnit 3 offered methods `setUp` and `tearDown` for this purpose. In ScalaTest, you can use the `BeforeAndAfterEach` trait, which will be described later, to implement an approach similar to JUnit's `setUp` and `tearDown`, however, this approach usually involves reassigning `var`s or mutating objects between tests. Before going that route, you may wish to consider some more functional approaches that avoid side effects.

###### Calling create-fixture methods

One approach is to write one or more create-fixture methods that return a new instance of a needed fixture object (or an holder object containing multiple needed fixture objects) each time it is called. You can then call a create-fixture method at the beginning of each test method that needs the fixture, storing the returned object or objects in local variables. Here's an example:

    import org.scalatest.Suite
    import collection.mutable.ListBuffer

    class ExampleSuite extends Suite {

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

      def testEasy {
        val f = fixture
        f.builder.append("easy!")
        assert(f.builder.toString === "ScalaTest is easy!")
        assert(f.buffer.isEmpty)
        f.buffer += "sweet"
      }

      def testFun {
        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.

###### Instantiating fixture traits

A related technique is to place the fixture objects in a fixture trait and run your test code in the context of a new anonymous class instance that mixes in the fixture trait, like this:

    import org.scalatest.Suite
    import collection.mutable.ListBuffer

    class ExampleSuite extends Suite {

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

      def testEasy {
        new Fixture {
          builder.append("easy!")
          assert(builder.toString === "ScalaTest is easy!")
          assert(buffer.isEmpty)
          buffer += "sweet"
        }
      }

      def testFun {
        new Fixture {
          builder.append("fun!")
          assert(builder.toString === "ScalaTest is fun!")
          assert(buffer.isEmpty)
        }
      }
    }

###### Mixing in `OneInstancePerTest`

If every test method requires the same set of mutable fixture objects, one other approach you can take is make them simply `val`s 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:

    import org.scalatest.Suite
    import org.scalatest.OneInstancePerTest
    import collection.mutable.ListBuffer

    class ExampleSuite extends Suite with OneInstancePerTest {

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

      def testEasy {
        builder.append("easy!")
        assert(builder.toString === "ScalaTest is easy!")
        assert(buffer.isEmpty)
        buffer += "sweet"
      }

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

Although the create-fixture, fixture-trait, and `OneInstancePerTest` approaches take care of setting up a fixture before each test, they don't address the problem of cleaning up a fixture after the test completes. In this situation, you'll need to either use side effects or the loan pattern.

###### Mixing in `BeforeAndAfter`

One way to use side effects is to mix in the `BeforeAndAfter` trait. 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:

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

    class ExampleSuite extends Suite with BeforeAndAfter {

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

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

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

      def testEasy {
        builder.append("easy!")
        assert(builder.toString === "ScalaTest is easy!")
        assert(buffer.isEmpty)
        buffer += "sweet"
      }

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

###### Overriding `withFixture(NoArgTest)`

An alternate way to take care of setup and cleanup via side effects is to override `withFixture`. Trait `Suite`'s implementation of `runTest` passes a no-arg test function to `withFixture`. It is `withFixture`'s responsibility to invoke that test function. `Suite`'s implementation of `withFixture` simply invokes the function, like this:

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

You can, therefore, override `withFixture` to perform setup before, and 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. Here's an example:

    import org.scalatest.Suite
    import collection.mutable.ListBuffer

    class ExampleSuite extends Suite {

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

      override def withFixture(test: NoArgTest) {
        builder.append("ScalaTest is ") // perform setup
        try {
          test() // invoke the test function
        }
        finally {
          builder.clear() // perform cleanup
          buffer.clear()
        }
      }

      def testEasy {
        builder.append("easy!")
        assert(builder.toString === "ScalaTest is easy!")
        assert(buffer.isEmpty)
        buffer += "sweet"
      }

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

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

The reason you should perform cleanup in a `finally` clause is that `withFixture` is called by `runTest`, which expects an exception to be thrown to indicate a failed test. Thus when you invoke the `test` function inside `withFixture`, it may complete abruptly with an exception. The `finally` clause will ensure the fixture cleanup happens as that exception propagates back up the call stack to `runTest`.

###### Overriding `withFixture(OneArgTest)`

To use the loan pattern, you can extend `FixtureSuite` (from the `org.scalatest.fixture` package) instead of `Suite`. Each test in a `FixtureSuite` 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. Here's an example:

    import org.scalatest.fixture.FixtureSuite
    import java.io.FileWriter
    import java.io.File

    class ExampleSuite extends FixtureSuite {

      final val tmpFile = "temp.txt"

      type FixtureParam = FileWriter

      def withFixture(test: OneArgTest) {

        val writer = new FileWriter(tmpFile) // set up the fixture
        try {
          test(writer) // "loan" the fixture to the test
        }
        finally {
          writer.close() // clean up the fixture
        }
      }

      def testEasy(writer: FileWriter) {
        writer.write("Hello, test!")
        writer.flush()
        assert(new File(tmpFile).length === 12)
      }

      def testFun(writer: FileWriter) {
        writer.write("Hi, test!")
        writer.flush()
        assert(new File(tmpFile).length === 9)
      }
    }

For more information, see the documentation for `FixtureSuite`.

#### Providing different fixtures to different tests

If different tests in the same `Suite` require different fixtures, you can combine the previous techniques and provide each test with just the fixture or fixtures it needs. Here's an example in which a `StringBuilder` and a `ListBuffer` are provided via fixture traits, and file writer (that requires cleanup) is provided via the loan pattern:

    import java.io.FileWriter
    import java.io.File
    import collection.mutable.ListBuffer
    import org.scalatest.Suite

    class ExampleSuite extends Suite {

      final val tmpFile = "temp.txt"

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

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

      def withWriter(testCode: FileWriter => Any) {
        val writer = new FileWriter(tmpFile) // set up the fixture
        try {
          testCode(writer) // "loan" the fixture to the test
        }
        finally {
          writer.close() // clean up the fixture
        }
      }

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

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

      def testFriendly { // This test needs the FileWriter fixture
        withWriter { writer =>
          writer.write("Hello, user!")
          writer.flush()
          assert(new File(tmpFile).length === 12)
        }
      }

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

      def testComposable { // This test needs all three fixtures
        new Builder with Buffer {
          builder.append("clear!")
          buffer += ("concise!")
          assert(builder.toString === "ScalaTest is clear!")
          assert(buffer === List("ScalaTest", "is", "concise!"))
          withWriter { writer =>
            writer.write(builder.toString)
            writer.flush()
            assert(new File(tmpFile).length === 19)
          }
        }
      }
    }

In the previous example, `testProductive` uses only the `StringBuilder` fixture, so it just instantiates a `new Builder`, whereas `testReadable` uses only the `ListBuffer` fixture, so it just intantiates a `new Buffer`. `testFriendly` needs just the `FileWriter` fixture, so it invokes `withWriter`, which prepares and passes a `FileWriter` to the test (and takes care of closing it afterwords).

Two tests need multiple fixtures: `testClearAndConcise` needs both the `StringBuilder` and the `ListBuffer`, so it instantiates a class that mixes in both fixture traits with `new Builder with Buffer`. `testComposable` needs all three fixtures, so in addition to `new Builder with Buffer` it also invokes `withWriter`, wrapping just the of the test code that needs the fixture.

Note that in this case, the loan pattern is being implemented via the `withWriter` method that takes a function, not by overriding `FixtureSuite`'s `withFixture(OneArgTest)` method. `FixtureSuite` makes the most sense if all (or at least most) tests need the same fixture, whereas in this `Suite` only two tests need the `FileWriter`.

Note also that two test methods, `testFriendly` and `testComposable`, are declared as parameterless methods even though they have a side effect. In production code you would normally declare these 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.

In the previous example, the `withWriter` method passed an object into the tests. Passing fixture objects into tests is generally a good idea when possible, but sometimes a side affect is unavoidable. For example, if you need to initialize a database running on a server across a network, your with-fixture method will likely have nothing to pass. In such cases, simply create a with-fixture method that takes a by-name parameter and performs setup and cleanup via side effects, like this:

    def withDataInDatabase(test: => Any) {
      // initialize the database across the network
      try {
        test // "loan" the initialized database to the test
      }
      finally {
        // clean up the database
      }
    }

You can then use it like:

    def testUserLogsIn {
      withDataInDatabase {
        // test user logging in scenario
      }
    }

#### Composing stackable fixture 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`:

    import org.scalatest.Suite
    import org.scalatest.AbstractSuite
    import collection.mutable.ListBuffer

    trait Builder extends AbstractSuite { 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 AbstractSuite { 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 ExampleSuite extends Suite with Builder with Buffer {

      def testEasy {
        builder.append("easy!")
        assert(builder.toString === "ScalaTest is easy!")
        assert(buffer.isEmpty)
        buffer += "sweet"
      }

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

By mixing in both the `Builder` and `Buffer` traits, `ExampleSuite` 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 Example2Suite extends Suite with Buffer with Builder

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

    class Example3Suite extends Suite 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`:

    import org.scalatest.Suite
    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 ExampleSuite extends Suite with Builder with Buffer {

      def testEasy {
        builder.append("easy!")
        assert(builder.toString === "ScalaTest is easy!")
        assert(buffer.isEmpty)
        buffer += "sweet"
      }

      def testFun {
        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.afterAll` throws an exception.

One difference to bear in mind between the before-and-after traits and the `withFixture` methods, is that if a `withFixture` method completes abruptly with an exception, it is considered a failed test. By contrast, if any of the methods on the before-and-after traits (i.e., `before` and `after` of `BeforeAndAfter`, `beforeEach` and `afterEach` of `BeforeAndAfterEach`, and `beforeAll` and `afterAll` of `BeforeAndAfterAll`) complete abruptly, it is considered a failed suite, which will result in a `SuiteAborted` event.

#### Treatment of `java.lang.Error`s

The Javadoc documentation for `java.lang.Error` states:

> An `Error` is a subclass of `Throwable` that indicates serious problems that a reasonable application should not try to catch. Most such errors are abnormal conditions.

Because `Error`s are used to denote serious errors, trait `Suite` and its subtypes in the ScalaTest API do not always treat a test that completes abruptly with an `Error` as a test failure, but sometimes as an indication that serious problems have arisen that should cause the run to abort. For example, if a test completes abruptly with an `OutOfMemoryError`, it will not be reported as a test failure, but will instead cause the run to abort. Because not everyone uses `Error`s only to represent serious problems, however, ScalaTest only behaves this way for the following exception types (and their subclasses):

- `java.lang.annotation.AnnotationFormatError`
- `java.awt.AWTError`
- `java.nio.charset.CoderMalfunctionError`
- `javax.xml.parsers.FactoryConfigurationError`
- `java.lang.LinkageError`
- `java.lang.ThreadDeath`
- `javax.xml.transform.TransformerFactoryConfigurationError`
- `java.lang.VirtualMachineError`

The previous list includes all `Error`s that exist as part of Java 1.5 API, excluding `java.lang.AssertionError`. ScalaTest does treat a thrown `AssertionError` as an indication of a test failure. In addition, any other `Error` that is not an instance of a type mentioned in the previous list will be caught by the `Suite` traits in the ScalaTest API and reported as the cause of a test failure.

Although trait `Suite` and all its subtypes in the ScalaTest API consistently behave this way with regard to `Error`s, this behavior is not required by the contract of `Suite`. Subclasses and subtraits that you define, for example, may treat all `Error`s as test failures, or indicate errors in some other way that has nothing to do with exceptions.

#### Extensibility

Trait `Suite` provides default implementations of its methods that should be sufficient for most applications, but many methods can be overridden when desired. Here's a summary of the methods that are intended to be overridden:

- `run` - override this method to define custom ways to run suites of tests.
- `runNestedSuites` - override this method to define custom ways to run nested suites.
- `runTests` - override this method to define custom ways to run a suite's tests.
- `runTest` - override this method to define custom ways to run a single named test.
- `testNames` - override this method to specify the `Suite`'s test names in a custom way.
- `tags` - override this method to specify the `Suite`'s test tags in a custom way.
- `nestedSuites` - override this method to specify the `Suite`'s nested `Suite`s in a custom way.
- `suiteName` - override this method to specify the `Suite`'s name in a custom way.
- `expectedTestCount` - override this method to count this `Suite`'s expected tests in a custom way.

For example, this trait's implementation of `testNames` performs reflection to discover methods starting with `test`, and places these in a `Set` whose iterator returns the names in alphabetical order. If you wish to run tests in a different order in a particular `Suite`, perhaps because a test named `testAlpha` can only succeed after a test named `testBeta` has run, you can override `testNames` so that it returns a `Set` whose iterator returns `testBeta` before `testAlpha`. (This trait's implementation of `run` will invoke tests in the order they come out of the `testNames` `Set` iterator.)

Alternatively, you may not like starting your test methods with `test`, and prefer using `@Test` annotations in the style of Java's JUnit 4 or TestNG. If so, you can override `testNames` to discover tests using either of these two APIs `@Test` annotations, or one of your own invention. (This is in fact how `org.scalatest.junit.JUnitSuite` and `org.scalatest.testng.TestNGSuite` work.)

Moreover, test in ScalaTest does not necessarily mean test method. A test can be anything that can be given a name, that starts and either succeeds or fails, and can be ignored. In `org.scalatest.FunSuite`, for example, tests are represented as function values. This approach might look foreign to JUnit users, but may feel more natural to programmers with a functional programming background. To facilitate this style of writing tests, `FunSuite` overrides `testNames`, `runTest`, and `run` such that you can define tests as function values.

You can also model existing JUnit 3, JUnit 4, or TestNG tests as suites of tests, thereby incorporating tests written in Java into a ScalaTest suite. The "wrapper" classes in packages `org.scalatest.junit` and `org.scalatest.testng` exist to make this easy. No matter what legacy tests you may have, it is likely you can create or use an existing `Suite` subclass that allows you to model those tests as ScalaTest suites and tests and incorporate them into a ScalaTest suite. You can then write new tests in Scala and continue supporting older tests in Java.

Self Type
  Suite
Annotations
  @serializable()

Linear Supertypes
AbstractSuite, Assertions, AnyRef, Any
Known Subclasses
FeatureSpec, FixtureFeatureSpec, FixtureFlatSpec, FixtureFreeSpec, FixtureFunSuite, FixturePropSpec, FixtureSpec, FixtureSuite, FixtureWordSpec, FlatSpec, FreeSpec, FunSuite, JUnit3Suite, JUnitSuite, JUnitWrapperSuite, MultipleFixtureFeatureSpec, MultipleFixtureFlatSpec, MultipleFixtureFreeSpec, MultipleFixtureFunSuite, MultipleFixturePropSpec, MultipleFixtureSpec, MultipleFixtureWordSpec, PropSpec, Spec, Specs, Suites, SuperSuite, TestNGSuite, TestNGWrapperSuite, WordSpec
Ordering

1. Alphabetic
2. By inheritance

Inherited

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1. Suite
2. AbstractSuite
3. Assertions
4. AnyRef
5. Any

Visibility

1. Public
2. All

### Type Members

1. #### class Equalizer extends AnyRef

   Class used via an implicit conversion to enable any two objects to be compared with `===` in assertions in tests.

2. #### trait NoArgTest extends () ⇒ Unit

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

### Value Members

1. #### def != (arg0: AnyRef): Boolean

   Attributes
     final
   Definition Classes
     AnyRef

2. #### def != (arg0: Any): Boolean

   Attributes
     final
   Definition Classes
     Any

3. #### def ## (): Int

   Attributes
     final
   Definition Classes
     AnyRef → Any

4. #### def == (arg0: AnyRef): Boolean

   Attributes
     final
   Definition Classes
     AnyRef

5. #### def == (arg0: Any): Boolean

   Attributes
     final
   Definition Classes
     Any

6. #### def asInstanceOf [T0] : T0

   Attributes
     final
   Definition Classes
     Any

7. #### 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

8. #### 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 `message`, 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

9. #### 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 `message` 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

10. #### 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

11. #### def clone (): AnyRef

    Attributes
      protected[lang]
    Definition Classes
      AnyRef
    Annotations
      @throws()

12. #### 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 `Suite`s. 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

13. #### def eq (arg0: AnyRef): Boolean

    Attributes
      final
    Definition Classes
      AnyRef

14. #### def equals (arg0: Any): Boolean

    Definition Classes
      AnyRef → Any

15. #### 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()

    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

16. #### def expect (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 `==`), `expect` returns normally. Else, `expect` throws an `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

17. #### def expect (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 `==`), `expect` returns normally. Else, if `actual` is not equal to `expected`, `expect` throws an `TestFailedException` whose detail message includes the expected and actual values, as well as the `String` obtained by invoking `toString` on the passed `message`.

    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

18. #### 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
    - 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

    Definition Classes
      Suite → AbstractSuite

19. #### 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

20. #### 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

21. #### 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

22. #### def fail (): Nothing

    Throws `TestFailedException` to indicate a test failed.

    Throws `TestFailedException` to indicate a test failed.

    Definition Classes
      Assertions

23. #### def finalize (): Unit

    Attributes
      protected[lang]
    Definition Classes
      AnyRef
    Annotations
      @throws()

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

    Attributes
      final
    Definition Classes
      AnyRef

25. #### def hashCode (): Int

    Definition Classes
      AnyRef → Any

26. #### 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

27. #### def isInstanceOf [T0] : Boolean

    Attributes
      final
    Definition Classes
      Any

28. #### def ne (arg0: AnyRef): Boolean

    Attributes
      final
    Definition Classes
      AnyRef

29. #### def nestedSuites : List[Suite]

    A `List` of this `Suite` object's nested `Suite`s.

    A `List` of this `Suite` object's nested `Suite`s. If this `Suite` contains no nested `Suite`s, this method returns an empty `List`. This trait's implementation of this method returns an empty `List`.

    Definition Classes
      Suite → AbstractSuite

30. #### def notify (): Unit

    Attributes
      final
    Definition Classes
      AnyRef

31. #### def notifyAll (): Unit

    Attributes
      final
    Definition Classes
      AnyRef

32. #### 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 `Spec` 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.

33. #### 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`

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

    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 `runTests`s. 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`.

    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 `Suite`s to be run by another entity, such as concurrently by a pool of threads. If `None`, nested `Suite`s will be run sequentially.

    tracker

      a `Tracker` tracking `Ordinal`s being fired by the current thread.

    Definition Classes
      Suite → AbstractSuite

35. #### def runNestedSuites (reporter: Reporter, stopper: Stopper, filter: Filter, configMap: Map[String, Any], distributor: Option[Distributor], tracker: Tracker): Unit

    Run zero to many of this `Suite`'s nested `Suite`s.

    Run zero to many of this `Suite`'s nested `Suite`s.

    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 `Suite`s 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`.

    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 `Suite`s to be run by another entity, such as concurrently by a pool of threads. If `None`, nested `Suite`s will be run sequentially.

    tracker

      a `Tracker` tracking `Ordinal`s being fired by the current thread.

    Attributes
      protected
    Definition Classes
      Suite → AbstractSuite

36. #### def runTest (testName: String, reporter: Reporter, stopper: Stopper, configMap: Map[String, Any], tracker: Tracker): Unit

    Run a test.

    Run a test.

    This trait's implementation uses Java reflection to invoke on this object the test method identified by the passed `testName`.

    Implementations of this method are responsible for ensuring a `TestStarting` event is fired to the `Reporter` before executing any test, and either `TestSucceeded`, `TestFailed`, or `TestPending` after executing any nested `Suite`. (If a test is marked with the `org.scalatest.Ignore` tag, the `runTests` method is responsible for ensuring a `TestIgnored` event is fired and that this `runTest` method is not invoked for that ignored test.)

    testName

      the name of one test to run.

    reporter

      the `Reporter` to which results will be reported

    stopper

      the `Stopper` that will be consulted to determine whether to stop execution early.

    configMap

      a `Map` of key-value pairs that can be used by the executing `Suite` of tests.

    tracker

      a `Tracker` tracking `Ordinal`s being fired by the current thread.

    Attributes
      protected
    Definition Classes
      Suite → AbstractSuite

37. #### def runTests (testName: Option[String], reporter: Reporter, stopper: Stopper, filter: Filter, configMap: Map[String, Any], distributor: Option[Distributor], tracker: Tracker): Unit

    Run zero to many of this `Suite`'s tests.

    Run zero to many of this `Suite`'s tests.

    This method takes a `testName` parameter that optionally specifies a test to invoke. If `testName` is defined, this trait's implementation of this method invokes `runTest` on this object, passing in:

    - `testName` - the `String` value of the `testName` `Option` passed to this method
    - `reporter` - the `Reporter` passed to this method, or one that wraps and delegates to it
    - `stopper` - the `Stopper` passed to this method, or one that wraps and delegates to it
    - `configMap` - the `configMap` `Map` passed to this method, or one that wraps and delegates to it

    This method takes a `Filter`, which encapsulates an optional `Set` of tag names that should be included (`tagsToInclude`) and a `Set` that should be excluded (`tagsToExclude`), when deciding which of this `Suite`'s tests to run. If `tagsToInclude` is `None`, all tests will be run except those those belonging to tags listed in the `tagsToExclude` `Set`. If `tagsToInclude` is defined, only tests belonging to tags mentioned in the `tagsToInclude` `Set`, and not mentioned in the `tagsToExclude`Set will be run. However, if `testName` is defined, `tagsToInclude` and `tagsToExclude` are essentially ignored. Only if `testName` is `None` will `tagsToInclude` and `tagsToExclude` be consulted to determine which of the tests named in the `testNames` `Set` should be run. This trait's implementation behaves this way, and it is part of the general contract of this method, so all overridden forms of this method should behave this way as well. For more information on test tags, see the main documentation for this trait and for class `Filter`. Note that this means that even if a test is marked as ignored, for example a test method in a `Suite` annotated with `org.scalatest.Ignore`, if that test name is passed as `testName` to `runTest`, it will be invoked despite the `Ignore` annotation.

    If `testName` is `None`, this trait's implementation of this method invokes `testNames` on this `Suite` to get a `Set` of names of tests to potentially run. (A `testNames` value of `None` essentially acts as a wildcard that means all tests in this `Suite` that are selected by `tagsToInclude` and `tagsToExclude` should be run.) For each test in the `testName` `Set`, in the order they appear in the iterator obtained by invoking the `elements` method on the `Set`, this trait's implementation of this method checks whether the test should be run based on the `Filter`. If so, this implementation invokes `runTest`, passing in:

    - `testName` - the `String` name of the test to run (which will be one of the names in the `testNames` `Set`)
    - `reporter` - the `Reporter` passed to this method, or one that wraps and delegates to it
    - `stopper` - the `Stopper` passed to this method, or one that wraps and delegates to it
    - `configMap` - the `configMap` passed to this method, or one that wraps and delegates to it

    If a test is marked with the `org.scalatest.Ignore` tag, implementations of this method are responsible for ensuring a `TestIgnored` event is fired for that test and that `runTest` is not called for that test.

    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`.

    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 `Suite`s to be run by another entity, such as concurrently by a pool of threads. If `None`, nested `Suite`s will be run sequentially.

    tracker

      a `Tracker` tracking `Ordinal`s being fired by the current thread.

    Attributes
      protected
    Definition Classes
      Suite → AbstractSuite

38. #### 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 `Report`s to pass to the `suiteStarting`, `suiteCompleted`, and `suiteAborted` methods of the `Reporter`.

    returns

      this `Suite` object's suite name.

39. #### def synchronized [T0] (arg0: ⇒ T0): T0

    Attributes
      final
    Definition Classes
      AnyRef

40. #### def tags : Map[String, Set[String]]

    A `Map` whose keys are `String` tag names with which tests in this `Suite` are marked, and whose values are the `Set` of test names marked with each tag.

    A `Map` whose keys are `String` tag names with which tests in this `Suite` are marked, and whose values are the `Set` of test names marked with each tag. If this `Suite` contains no tags, this method returns an empty `Map`.

    This trait's implementation of this method uses Java reflection to discover any Java annotations attached to its test methods. The fully qualified name of each unique annotation that extends `TagAnnotation` is considered a tag. This trait's implementation of this method, therefore, places one key/value pair into to the `Map` for each unique tag annotation name discovered through reflection. The mapped value for each tag name key will contain the test method name, as provided via the `testNames` method.

    Subclasses may override this method to define and/or discover tags in a custom manner, but overriding method implementations should never return an empty `Set` as a value. If a tag has no tests, its name should not appear as a key in the returned `Map`.

    Definition Classes
      Suite → AbstractSuite

41. #### def testNames : Set[String]

    A `Set` of test names.

    A `Set` of test names. If this `Suite` contains no tests, this method returns an empty `Set`.

    This trait's implementation of this method uses Java reflection to discover all public methods whose name starts with `"test"`, which take either nothing or a single `Informer` as parameters. For each discovered test method, it assigns a test name comprised of just the method name if the method takes no parameters, or the method name plus `(Informer)` if the method takes a `Informer`. Here are a few method signatures and the names that this trait's implementation assigns them:

        def testCat() {}         // test name: "testCat"
        def testCat(Informer) {} // test name: "testCat(Informer)"
        def testDog() {}         // test name: "testDog"
        def testDog(Informer) {} // test name: "testDog(Informer)"
        def test() {}            // test name: "test"
        def test(Informer) {}    // test name: "test(Informer)"

    This trait's implementation of this method returns an immutable `Set` of all such names, excluding the name `testNames`. The iterator obtained by invoking `elements` on this returned `Set` will produce the test names in their natural order, as determined by `String`'s `compareTo` method.

    This trait's implementation of `runTests` invokes this method and calls `runTest` for each test name in the order they appear in the returned `Set`'s iterator. Although this trait's implementation of this method returns a `Set` whose iterator produces `String` test names in a well-defined order, the contract of this method does not required a defined order. Subclasses are free to override this method and return test names in an undefined order, or in a defined order that's different from `String`'s natural order.

    Subclasses may override this method to produce test names in a custom manner. One potential reason to override `testNames` is to run tests in a different order, for example, to ensure that tests that depend on other tests are run after those other tests. Another potential reason to override is allow tests to be defined in a different manner, such as methods annotated `@Test` annotations (as is done in `JUnitSuite` and `TestNGSuite`) or test functions registered during construction (as is done in `FunSuite` and `Spec`).

    Definition Classes
      Suite → AbstractSuite

42. #### def toString (): String

    Definition Classes
      AnyRef → Any

43. #### def wait (): Unit

    Attributes
      final
    Definition Classes
      AnyRef
    Annotations
      @throws()

44. #### def wait (arg0: Long, arg1: Int): Unit

    Attributes
      final
    Definition Classes
      AnyRef
    Annotations
      @throws()

45. #### def wait (arg0: Long): Unit

    Attributes
      final
    Definition Classes
      AnyRef
    Annotations
      @throws()

46. #### def withClue (clue: Any)(fun: ⇒ Unit): Unit

    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

47. #### 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 `var`s in this `Suite` or initializing a globally accessible external database. If you want to avoid reassigning instance `var`s you can use FixtureSuite.

    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

### Inherited from AbstractSuite

### Inherited from Assertions

### Inherited from AnyRef

### Inherited from Any