org.scalatest.fixture.FunSpec.scala Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of scalatest_2.9.0 Show documentation
ScalaTest is a free, open-source testing toolkit for Scala and Java programmers.
There is a newer version: 2.0.M6-SNAP4
/*
 * Copyright 2001-2009 Artima, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.scalatest.fixture

import org.scalatest._
import FixtureNodeFamily._
import scala.collection.immutable.ListSet
import org.scalatest.exceptions.StackDepthExceptionHelper.getStackDepthFun
import java.util.concurrent.atomic.AtomicReference
import java.util.ConcurrentModificationException
import org.scalatest.events._
import org.scalatest.Suite.anErrorThatShouldCauseAnAbort
import org.scalatest.Suite.autoTagClassAnnotations
import verb.BehaveWord
import FunSuite.IgnoreTagName 
import org.scalatest.exceptions.TestRegistrationClosedException

/**
 * A sister trait to org.scalatest.FunSpec that can pass a fixture object into its tests.
 *
 * 
 * Recommended Usage:
 * Use trait fixture.FunSpec in situations for which FunSpec
 * would be a good choice, when all or most tests need the same fixture objects
 * that must be cleaned up afterwords. Note: fixture.FunSpec is intended for use in special situations, with trait FunSpec used for general needs. For
 * more insight into where fixture.FunSpec fits in the big picture, see the withFixture(OneArgTest) subsection of the Shared fixtures section in the documentation for trait FunSpec.
 * 
 * 
 * 
 * Trait fixture.FunSpec behaves similarly to trait org.scalatest.FunSpec, except that tests may have a
 * fixture parameter. The type of the
 * fixture parameter is defined by the abstract FixtureParam type, which is declared as a member of this trait.
 * This trait also declares an abstract withFixture method. This withFixture method
 * takes a OneArgTest, which is a nested trait defined as a member of this trait.
 * OneArgTest has an apply method that takes a FixtureParam.
 * This apply method is responsible for running a test.
 * This trait's runTest method delegates the actual running of each test to withFixture(OneArgTest), passing
 * in the test code to run via the OneArgTest argument. The withFixture(OneArgTest) method (abstract in this trait) is responsible
 * for creating the fixture argument and passing it to the test function.
 * 
 * 
 * 
 * Subclasses of this trait must, therefore, do three things differently from a plain old org.scalatest.FunSpec:
 * 
 * 
 * 
 * define the type of the fixture parameter by specifying type FixtureParam
 * define the withFixture(OneArgTest) method
 * write tests that take a fixture parameter
 * (You can also define tests that don't take a fixture parameter.)
 * 
 *
 * 
 * If the fixture you want to pass into your tests consists of multiple objects, you will need to combine
 * them into one object to use this trait. One good approach to passing multiple fixture objects is
 * to encapsulate them in a case class. Here's an example:
 * 
 *
 *  * case class F(file: File, writer: FileWriter)
 * type FixtureParam = F
 * 
 *
 * 
 * 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.funspec.oneargtest
 * 
 * import org.scalatest.fixture
 * import java.io._
 * 
 * class ExampleSpec extends fixture.FunSpec {
 * 
 *   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
 *   }
 * 
 *   describe("Testing") {
 *     it("should be easy") { f =>
 *       f.writer.write("easy!")
 *       f.writer.flush()
 *       assert(f.file.length === 18)
 *     }
 * 
 *     it("should be fun") { f =>
 *       f.writer.write("fun!")
 *       f.writer.flush()
 *       assert(f.file.length === 17)
 *     }
 *   } 
 * }
 * 
 *
 * 
 * If a test fails, the OneArgTest function will complete abruptly with an exception describing the failure.
 * To ensure clean up happens even if a test fails, you should invoke the test function from inside a try block and do the cleanup in a
 * finally clause, as shown in the previous example.
 * 
 *
 * Sharing fixtures across classes
 *
 * 
 * If multiple test classes need the same fixture, you can define the FixtureParam and withFixture(OneArgTest) implementations
 * in a trait, then mix that trait into the test classes that need it. For example, if your application requires a database and your integration tests
 * use that database, you will likely have many test classes that need a database fixture. You can create a "database fixture" trait that creates a
 * database with a unique name, passes the connector into the test, then removes the database once the test completes. This is shown in the following example:
 * 
 * 
 *  * package org.scalatest.examples.fixture.funspec.sharing
 * 
 * import java.util.concurrent.ConcurrentHashMap
 * import org.scalatest.fixture
 * import DbServer._
 * import java.util.UUID.randomUUID
 * 
 * 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)
 *   }
 * }
 * 
 * trait DbFixture { this: fixture.Suite =>
 * 
 *   type FixtureParam = Db
 * 
 *   // Allow clients to populate the database after
 *   // it is created
 *   def populateDb(db: Db) {}
 * 
 *   def withFixture(test: OneArgTest) {
 *     val dbName = randomUUID.toString
 *     val db = createDb(dbName) // create the fixture
 *     try {
 *       populateDb(db) // setup the fixture
 *       withFixture(test.toNoArgTest(db)) // "loan" the fixture to the test
 *     }
 *     finally removeDb(dbName) // clean up the fixture
 *   }
 * }
 * 
 * class ExampleSpec extends fixture.FunSpec with DbFixture {
 * 
 *   override def populateDb(db: Db) { // setup the fixture
 *     db.append("ScalaTest is ")
 *   }
 * 
 *   describe("Testing") {
 *     it("should be easy") { db =>
 *       db.append("easy!")
 *       assert(db.toString === "ScalaTest is easy!")
 *     }
 *     
 *     it("should be fun") { db =>
 *       db.append("fun!")
 *       assert(db.toString === "ScalaTest is fun!")
 *     }
 *   }
 *   
 *   // This test doesn't need a Db
 *   describe("Test code") {
 *     it("should be clear") { () =>
 *       val buf = new StringBuffer
 *       buf.append("ScalaTest code is ")
 *       buf.append("clear!")
 *       assert(buf.toString === "ScalaTest code is clear!")
 *     }
 *   }
 * }
 * 
 *
 * 
 * Often when you create fixtures in a trait like DbFixture, you'll still need to enable individual test classes
 * to "setup" a newly created fixture before it gets passed into the tests. A good way to accomplish this is to pass the newly
 * created fixture into a setup method, like populateDb in the previous example, before passing it to the test
 * function. Classes that need to perform such setup can override the method, as does ExampleSpec.
 * 
 *
 * 
 * If a test doesn't need the fixture, you can indicate that by providing a no-arg instead of a one-arg function, as is done in the
 * third test in the previous example, “Test code should be clear”. In other words, instead of starting your function literal
 * with something like “db =>”, you'd start it with “() =>”. For such tests, runTest
 * will not invoke withFixture(OneArgTest). It will instead directly invoke withFixture(NoArgTest).
 * 
 *
 * 
 * Both examples shown above demonstrate 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 these examples. This keeps tests completely isolated, allowing you to run them in parallel if desired. You could mix
 * ParallelTestExecution into either of these ExampleSpec classes, and the tests would run in parallel just fine.
 * 
 *
 * @author Bill Venners
 */
@Finders(Array("org.scalatest.finders.FunSpecFinder"))
trait FunSpec extends Suite { thisSuite =>

  private final val engine = new FixtureEngine[FixtureParam]("concurrentFixtureSpecMod", "FixtureFunSpec")
  import engine._
  
  private[scalatest] val sourceFileName = "FunSpec.scala"

  /**
   * 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
   * FunSpec 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.
   */
  implicit protected def info: Informer = atomicInformer.get

  /**
   * Class that, via an instance referenced from the it field,
   * supports test (and shared test) registration in FunSpecs.
   *
   * 
   * This class supports syntax such as the following:
   * 
   *
   *    * it("should be empty")
   * ^
   * 
   *
   *    * it should behave like nonFullStack(stackWithOneItem)
   * ^
   * 
   *
   * 
   * For more information and examples, see the main documentation for FunSpec.
   * 
   */
  protected final class ItWord {

    /**
     * Register a test with the given spec text, optional tags, and test function value that takes no arguments.
     * An invocation of this method is called an “example.”
     *
     * This method will register the test for later execution via an invocation of one of the execute
     * methods. The name of the test will be a concatenation of the text of all surrounding describers,
     * from outside in, and the passed spec text, with one space placed between each item. (See the documenation
     * for testNames for an example.) The resulting test name must not have been registered previously on
     * this FunSpec instance.
     *
     * @param specText the specification text, which will be combined with the descText of any surrounding describers
     * to form the test name
     * @param testTags the optional list of tags for this test
     * @param testFun the test function
     * @throws DuplicateTestNameException if a test with the same name has been registered previously
     * @throws TestRegistrationClosedException if invoked after run has been invoked on this suite
     * @throws NullPointerException if specText or any passed test tag is null
     */
    def apply(specText: String, testTags: Tag*)(testFun: FixtureParam => Any) {
      registerTest(specText, testFun, "itCannotAppearInsideAnotherIt", sourceFileName, "apply", 3, -2, None, None, None, testTags: _*)
    }

    /**
     * Supports the registration of shared tests.
     *
     * 
     * This method supports syntax such as the following:
     * 
     *
     *      * it should behave like nonFullStack(stackWithOneItem)
     *    ^
     * 
     *
     * 
     * For examples of shared tests, see the Shared tests section
     * in the main documentation for trait FunSpec.
     * 
     */
    def should(behaveWord: BehaveWord) = behaveWord

    /**
     * Supports the registration of shared tests.
     *
     * 
     * This method supports syntax such as the following:
     * 
     *
     *      * it must behave like nonFullStack(stackWithOneItem)
     *    ^
     * 
     *
     * 
     * For examples of shared tests, see the Shared tests section
     * in the main documentation for trait FunSpec.
     * 
     */
    def must(behaveWord: BehaveWord) = behaveWord
  }

  /**
   * Supports test (and shared test) registration in FunSpecs.
   *
   * 
   * This field supports syntax such as the following:
   * 
   *
   *    * it("should be empty")
   * ^
   * 
   *
   *    * it should behave like nonFullStack(stackWithOneItem)
   * ^
   * 
   *
   * 
   * For more information and examples of the use of the it field, see
   * the main documentation for FunSpec.
   * 
   */
  protected val it = new ItWord
  
  /**
   * Class that, via an instance referenced from the they field,
   * supports test (and shared test) registration in FunSpecs.
   *
   * 
   * This class supports syntax such as the following:
   * 
   *
   *    * they("should be empty")
   * ^
   * 
   *
   *    * they should behave like nonFullStack(stackWithOneItem)
   * ^
   * 
   *
   * 
   * For more information and examples, see the main documentation for FunSpec.
   * 
   */
  protected final class TheyWord {

    /**
     * Register a test with the given spec text, optional tags, and test function value that takes no arguments.
     * An invocation of this method is called an “example.”
     *
     * This method will register the test for later execution via an invocation of one of the execute
     * methods. The name of the test will be a concatenation of the text of all surrounding describers,
     * from outside in, and the passed spec text, with one space placed between each item. (See the documenation
     * for testNames for an example.) The resulting test name must not have been registered previously on
     * this FunSpec instance.
     *
     * @param specText the specification text, which will be combined with the descText of any surrounding describers
     * to form the test name
     * @param testTags the optional list of tags for this test
     * @param testFun the test function
     * @throws DuplicateTestNameException if a test with the same name has been registered previously
     * @throws TestRegistrationClosedException if invoked after run has been invoked on this suite
     * @throws NullPointerException if specText or any passed test tag is null
     */
    def apply(specText: String, testTags: Tag*)(testFun: FixtureParam => Any) {
      registerTest(specText, testFun, "theyCannotAppearInsideAnotherThey", sourceFileName, "apply", 3, -2, None, None, None, testTags: _*)
    }

    /**
     * Supports the registration of shared tests.
     *
     * 
     * This method supports syntax such as the following:
     * 
     *
     *      * they should behave like nonFullStack(stackWithOneItem)
     *      ^
     * 
     *
     * 
     * For examples of shared tests, see the Shared tests section
     * in the main documentation for trait FunSpec.
     * 
     */
    def should(behaveWord: BehaveWord) = behaveWord

    /**
     * Supports the registration of shared tests.
     *
     * 
     * This method supports syntax such as the following:
     * 
     *
     *      * they must behave like nonFullStack(stackWithOneItem)
     *      ^
     * 
     *
     * 
     * For examples of shared tests, see the Shared tests section
     * in the main documentation for trait FunSpec.
     * 
     */
    def must(behaveWord: BehaveWord) = behaveWord
  }

  /**
   * Supports test (and shared test) registration in FunSpecs.
   *
   * 
   * This field supports syntax such as the following:
   * 
   *
   *    * they("should be empty")
   * ^
   * 
   *
   *    * they should behave like nonFullStack(stackWithOneItem)
   * ^
   * 
   *
   * 
   * For more information and examples of the use of the it field, see
   * the main documentation for FunSpec.
   * 
   */
  protected val they = new TheyWord

  /**
   * Register a test to ignore, which has the given spec text, optional tags, and test function value that takes no arguments.
   * This method will register the test for later ignoring via an invocation of one of the execute
   * methods. This method exists to make it easy to ignore an existing test by changing the call to it
   * to ignore without deleting or commenting out the actual test code. The test will not be executed, but a
   * report will be sent that indicates the test was ignored. The name of the test will be a concatenation of the text of all surrounding describers,
   * from outside in, and the passed spec text, with one space placed between each item. (See the documenation
   * for testNames for an example.) The resulting test name must not have been registered previously on
   * this FunSpec instance.
   *
   * @param specText the specification text, which will be combined with the descText of any surrounding describers
   * to form the test name
   * @param testTags the optional list of tags for this test
   * @param testFun the test function
   * @throws DuplicateTestNameException if a test with the same name has been registered previously
   * @throws TestRegistrationClosedException if invoked after run has been invoked on this suite
   * @throws NullPointerException if specText or any passed test tag is null
   */
  protected def ignore(specText: String, testTags: Tag*)(testFun: FixtureParam => Any) {
    registerIgnoredTest(specText, testFun, "ignoreCannotAppearInsideAnIt", sourceFileName, "ignore", 6, -2, None, testTags: _*)
  }

  /**
   * Register a test to ignore, which has the given spec text and test function value that takes no arguments.
   * This method will register the test for later ignoring via an invocation of one of the execute
   * methods. This method exists to make it easy to ignore an existing test by changing the call to it
   * to ignore without deleting or commenting out the actual test code. The test will not be executed, but a
   * report will be sent that indicates the test was ignored. The name of the test will be a concatenation of the text of all surrounding describers,
   * from outside in, and the passed spec text, with one space placed between each item. (See the documenation
   * for testNames for an example.) The resulting test name must not have been registered previously on
   * this FunSpec instance.
   *
   * @param specText the specification text, which will be combined with the descText of any surrounding describers
   * to form the test name
   * @param testFun the test function
   * @throws DuplicateTestNameException if a test with the same name has been registered previously
   * @throws TestRegistrationClosedException if invoked after run has been invoked on this suite
   * @throws NullPointerException if specText or any passed test tag is null
   */
  protected def ignore(specText: String)(testFun: FixtureParam => Any) {
    if (atomic.get.registrationClosed)
      throw new TestRegistrationClosedException(Resources("ignoreCannotAppearInsideAnIt"), getStackDepthFun(sourceFileName, "ignore"))
    ignore(specText, Array[Tag](): _*)(testFun)
  }

  /**
   * Describe a “subject” being specified and tested by the passed function value. The
   * passed function value may contain more describers (defined with describe) and/or tests
   * (defined with it). This trait's implementation of this method will register the
   * description string and immediately invoke the passed function.
   */
  protected def describe(description: String)(fun: => Unit) {
    registerNestedBranch(description, None, fun, "describeCannotAppearInsideAnIt", sourceFileName, "describe", 4, -2, None)
  }

  /**
   * A Map whose keys are String tag names to which tests in this FunSpec belong, and values
   * the Set of test names that belong to each tag. If this FunSpec 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.
   * 
   */
  override def tags: Map[String, Set[String]] = autoTagClassAnnotations(atomic.get.tagsMap, this)

  /**
   * 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.)
   *
   * @param testName the name of one test to execute.
   * @param args the Args for this run
   *
   * @throws NullPointerException if any of testName, reporter, stopper, or configMap
   *     is null.
   */
  protected override def runTest(testName: String, args: Args): Status = {

    def invokeWithFixture(theTest: TestLeaf) {
      theTest.testFun match {
        case wrapper: NoArgTestWrapper[_] =>
          withFixture(new FixturelessTestFunAndConfigMap(testName, wrapper.test, args.configMap))
        case fun => withFixture(new TestFunAndConfigMap(testName, fun, args.configMap))
      }
    }

    runTestImpl(thisSuite, testName, args, true, invokeWithFixture)
  }

  /**
   * 
   * Run zero to many of this FunSpec's tests.
   * 
   *
   * 
   * This method takes a testName parameter that optionally specifies a test to invoke.
   * If testName is Some, 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 passed to this method, or one that wraps and delegates to it
   * 
   *
   * 
   * This method takes a 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 execute.
   * If tagsToInclude is empty, all tests will be executed
   * except those those belonging to tags listed in the tagsToExclude Set. If tagsToInclude is non-empty, only tests
   * belonging to tags mentioned in tagsToInclude, and not mentioned in tagsToExclude
   * will be executed. However, if testName is Some, 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. For more information on trait tags, see the main documentation for this trait.
   * 
   *
   * 
   * 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 execute.
   * (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 executed.)
   * 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 tagsToInclude and tagsToExclude Sets.
   * 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
   * 
   *
   * @param 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 FunSpec.
   * @param args the Args to which results will be reported
   *
   * @throws NullPointerException if any of testName or args is null.
   */
  protected override def runTests(testName: Option[String], args: Args): Status = {

    runTestsImpl(thisSuite, testName, args, info, true, runTest)
  }

  /**
   * An immutable Set of test names. If this FunSpec 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.
   * 
   */
  override def testNames: Set[String] = {
    // I'm returning a ListSet here so that they tests will be run in registration order
    ListSet(atomic.get.testNamesList.toArray: _*)
  }

  override def run(testName: Option[String], args: Args): Status = {
    runImpl(thisSuite, testName, args, super.run)
  }

  /**
   * Supports shared test registration in FunSpecs.
   *
   * 
   * This field supports syntax such as the following:
   * 
   *
   *    * it should behave like nonFullStack(stackWithOneItem)
   *           ^
   * 
   *
   * 
   * For more information and examples of the use of behave, see the Shared tests section
   * in the main documentation for trait FunSpec.
   * 
   */
  protected val behave = new BehaveWord

  /**
   * Implicitly converts a function that takes no parameters and results in PendingNothing to
   * a function from FixtureParam to Any, to enable pending tests to registered as by-name parameters
   * by methods that require a test function that takes a FixtureParam.
   *
   * 
   * This method makes it possible to write pending tests as simply (pending), without needing
   * to write (fixture => pending).
   * 
   */
  protected implicit def convertPendingToFixtureFunction(f: => PendingNothing): FixtureParam => Any = {
    fixture => f
  }

  /**
   * Implicitly converts a function that takes no parameters and results in Any to
   * a function from FixtureParam to Any, to enable no-arg tests to registered
   * by methods that require a test function that takes a FixtureParam.
   */
  protected implicit def convertNoArgToFixtureFunction(fun: () => Any): (FixtureParam => Any) =
    new NoArgTestWrapper(fun)
  
  /**
   * Suite style name.
   */
  final override val styleName: String = "org.scalatest.fixture.FunSpec"
    
  override def testDataFor(testName: String, theConfigMap: Map[String, Any] = Map.empty): TestData = createTestDataFor(testName, theConfigMap, this)
}