org.scalatest.fixture.FeatureSpec.scala Maven / Gradle / Ivy
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/*
* 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.exceptions.NotAllowedException
/**
* A sister trait to org.scalatest.FeatureSpec that can pass a fixture object into its tests.
*
*
* The purpose of FeatureSpec and its subtraits is to facilitate writing tests in
* a functional style. Some users may prefer writing tests in a functional style in general, but one
* particular use case is parallel test execution (See ParallelTestExecution). To run
* tests in parallel, your test class must
* be thread safe, and a good way to make it thread safe is to make it functional. A good way to
* write tests that need common fixtures in a functional style is to pass the fixture objects into the tests,
* the style enabled by the fixture.Suite family of traits.
*
*
*
* Trait FeatureSpec behaves similarly to trait org.scalatest.FeatureSpec, 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, passing
* in the test code to run via the OneArgTest argument. The withFixture 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.FeatureSpec:
*
*
*
* - 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.)
*
*
*
* Here's an example:
*
*
*
* import org.scalatest.fixture
* import collection.mutable.Stack
* import java.util.NoSuchElementException
*
* class StackSpec extends fixture.FeatureSpec {
*
* // 1. define type FixtureParam
* type FixtureParam = Stack[Int]
*
* // 2. define the withFixture method
* def withFixture(test: OneArgTest) {
* val stack = new Stack[Int]
* stack.push(1)
* stack.push(2)
* test(stack) // "loan" the fixture to the test
* }
*
* feature("Pushing a value onto a stack") {
*
* // 3. write tests that take a fixture parameter
* scenario("User pushes a value") { stack =>
* stack.push(9)
* assert(stack.size === 3)
* assert(stack.head === 9)
* }
* }
*
* feature("Popping a value off of a stack") {
*
* scenario("User pops a value") { stack =>
* val top = stack.pop()
* assert(top === 2)
* assert(stack.size === 1)
* }
*
* // 4. You can also write tests that don't take a fixture parameter.
* scenario("User calls pop on an empty stack") { () =>
* intercept[NoSuchElementException] {
* (new Stack[Int]).pop()
* }
* }
* }
* }
*
*
*
* In the previous example, withFixture creates and initializes a stack, then invokes the test function, passing in
* the stack. In addition to setting up a fixture before a test, the withFixture method also allows you to
* clean it up afterwards, if necessary. If you need to do some clean up that must happen even if a test
* fails, you should invoke the test function from inside a try block and do the cleanup in a
* finally clause, like this:
*
*
*
* def withFixture(test: OneArgTest) {
* val resource = someResource.open() // set up the fixture
* try {
* test(resource) // if the test fails, test(...) will throw an exception
* }
* finally {
* // clean up the fixture no matter whether the test succeeds or fails
* resource.close()
* }
* }
*
*
*
* The reason you must 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, 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.
*
*
*
* 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:
*
*
*
* import org.scalatest.fixture
* import scala.collection.mutable.ListBuffer
*
* class ExampleSpec extends fixture.FeatureSpec {
*
* case class F(builder: StringBuilder, buffer: ListBuffer[String])
* type FixtureParam = F
*
* def withFixture(test: OneArgTest) {
*
* // Create needed mutable objects
* val stringBuilder = new StringBuilder("ScalaTest is ")
* val listBuffer = new ListBuffer[String]
*
* // Invoke the test function, passing in the mutable objects
* test(F(stringBuilder, listBuffer))
* }
*
* scenario("User finds testing easy") { f =>
* f.builder.append("easy!")
* assert(f.builder.toString === "ScalaTest is easy!")
* assert(f.buffer.isEmpty)
* f.buffer += "sweet"
* }
*
* scenario("User finds testing fun") { f =>
* f.builder.append("fun!")
* assert(f.builder.toString === "ScalaTest is fun!")
* assert(f.buffer.isEmpty)
* }
* }
*
*
* Configuring fixtures and tests
*
*
* Sometimes you may want to write tests that are configurable. For example, you may want to write
* a suite of tests that each take an open temp file as a fixture, but whose file name is specified
* externally so that the file name can be can be changed from run to run. To accomplish this
* the OneArgTest trait has a configMap
* method, which will return a Map[String, Any] from which configuration information may be obtained.
* The runTest method of this trait will pass a OneArgTest to withFixture
* whose configMap method returns the configMap passed to runTest.
* Here's an example in which the name of a temp file is taken from the passed configMap:
*
*
*
* import org.scalatest.fixture
* import java.io.FileReader
* import java.io.FileWriter
* import java.io.File
*
* class ExampleSpec extends fixture.FeatureSpec {
*
* type FixtureParam = FileReader
* def withFixture(test: OneArgTest) {
*
* require(
* test.configMap.contains("TempFileName"),
* "This suite requires a TempFileName to be passed in the configMap"
* )
*
* // Grab the file name from the configMap
* val FileName = test.configMap("TempFileName").asInstanceOf[String]
*
* // Set up the temp file needed by the test
* val writer = new FileWriter(FileName)
* try {
* writer.write("Hello, test!")
* }
* finally {
* writer.close()
* }
*
* // Create the reader needed by the test
* val reader = new FileReader(FileName)
*
* try {
* // Run the test using the temp file
* test(reader)
* }
* finally {
* // Close and delete the temp file
* reader.close()
* val file = new File(FileName)
* file.delete()
* }
* }
*
* scenario("User reads the entire contents of a file") { reader =>
* var builder = new StringBuilder
* var c = reader.read()
* while (c != -1) {
* builder.append(c.toChar)
* c = reader.read()
* }
* assert(builder.toString === "Hello, test!")
* }
*
* scenario("User reads just the first char of a file") { reader =>
* assert(reader.read() === 'H')
* }
* }
*
*
*
* If you want to pass into each test the entire configMap that was passed to runTest, you
* can mix in trait ConfigMapFixture. See the documentation
* for ConfigMapFixture for the details, but here's a quick
* example of how it looks:
*
*
*
* import org.scalatest.fixture
* import org.scalatest.fixture.ConfigMapFixture
*
* class ExampleSpec extends fixture.FeatureSpec with ConfigMapFixture {
*
* feature("Test runs can be configured") {
*
* scenario("User wants to be greeted by the config map") { configMap =>
* // Use the configMap passed to runTest in the test
* assert(configMap.contains("hello"))
* }
*
* scenario("User wants the world from the config map") { configMap =>
* assert(configMap.contains("world"))
* }
* }
* }
*
*
* Providing multiple fixtures
*
*
* If different tests in the same FeatureSpec need different shared fixtures, you can use the loan pattern to supply to
* each test just the fixture or fixtures it needs. First select the most commonly used fixture objects and pass them in via the
* FixtureParam. Then for each remaining fixture needed by multiple tests, create a with<fixture name>
* method that takes a function you will use to pass the fixture to the test. Lasty, use the appropriate
* with<fixture name> method or methods in each test.
*
*
*
* In the following example, the FixtureParam is set to Map[String, Any] by mixing in ConfigMapFixture.
* The withFixture method in trait ConfigMapFixture will pass the config map to any test that needs it.
* In addition, some tests in the following example need a Stack[Int] and others a Stack[String].
* The withIntStack method takes
* care of supplying the Stack[Int] to those tests that need it, and the withStringStack method takes care
* of supplying the Stack[String] fixture. Here's how it looks:
*
*
*
* import org.scalatest.fixture
* import org.scalatest.fixture.ConfigMapFixture
* import collection.mutable.Stack
*
* class StackSpec extends fixture.FeatureSpec with ConfigMapFixture {
*
* def withIntStack(test: Stack[Int] => Any) {
* val stack = new Stack[Int]
* stack.push(1)
* stack.push(2)
* test(stack) // "loan" the Stack[Int] fixture to the test
* }
*
* def withStringStack(test: Stack[String] => Any) {
* val stack = new Stack[String]
* stack.push("one")
* stack.push("two")
* test(stack) // "loan" the Stack[String] fixture to the test
* }
*
* scenario("User pops an Int value") { () => // This test doesn't need the configMap fixture, ...
* withIntStack { stack =>
* val top = stack.pop() // But it needs the Stack[Int] fixture.
* assert(top === 2)
* assert(stack.size === 1)
* }
* }
*
* scenario("User pushes and Int value") { configMap =>
* withIntStack { stack =>
* val iToPush = // This test uses the configMap fixture...
* configMap("IntToPush").toString.toInt
* stack.push(iToPush) // And also uses the Stack[Int] fixture.
* assert(stack.size === 3)
* assert(stack.head === iToPush)
* }
* }
*
* scenario("User pops a String value") { () => // This test doesn't need the configMap fixture, ...
* withStringStack { stack =>
* val top = stack.pop() // But it needs the Stack[String] fixture.
* assert(top === "two")
* assert(stack.size === 1)
* }
* }
*
* scenario("User pushes a String value") { configMap =>
* withStringStack { stack =>
* val sToPush = // This test uses the configMap fixture...
* configMap("StringToPush").toString
* stack.push(sToPush) // And also uses the Stack[Int] fixture.
* assert(stack.size === 3)
* assert(stack.head === sToPush)
* }
* }
* }
*
*
*
* If you run the previous class in the Scala interpreter, you'll see:
*
*
*
* scala> import org.scalatest._
* import org.scalatest._
*
* scala> run(new StackSpec, configMap = Map("IntToPush" -> 9, "StringToPush" -> "nine"))
* StackSpec:
* - User pops an Int value
* - User pushes an Int value
* - User pops a String value
* - User pushes a String value
*
*
* @author Bill Venners
*/
trait FeatureSpec extends Suite { thisSuite =>
private final val engine = new FixtureEngine[FixtureParam]("concurrentFeatureSpecMod", "FixtureFeatureSpec")
import engine._
private[scalatest] val sourceFileName = "FeatureSpec.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
* FeatureSpec 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
/**
* 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 FeatureSpec 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 scenario(specText: String, testTags: Tag*)(testFun: FixtureParam => Any) {
registerTest(Resources("scenario", specText), testFun, "scenarioCannotAppearInsideAnotherScenario", sourceFileName, "scenario", 2, None, None, testTags: _*)
}
/**
* 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 FeatureSpec 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(Resources("scenario", specText), testFun , "ignoreCannotAppearInsideAScenario", sourceFileName, "ignore", 2, testTags: _*)
}
/**
* 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 feature(description: String)(fun: => Unit) {
if (!currentBranchIsTrunk)
throw new NotAllowedException(Resources("cantNestFeatureClauses"), getStackDepthFun(sourceFileName, "feature"))
registerNestedBranch(description, None, fun, "featureCannotAppearInsideAScenario", sourceFileName, "feature", 1)
}
/**
* A Map whose keys are String tag names to which tests in this FeatureSpec belong, and values
* the Set of test names that belong to each tag. If this FeatureSpec 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.
*
*/
override def tags: Map[String, Set[String]] = atomic.get.tagsMap
/**
* 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 reporter the Reporter to which results will be reported
* @param stopper the Stopper that will be consulted to determine whether to stop execution early.
* @param configMap a Map of properties that can be used by this FeatureSpec's executing tests.
* @throws NullPointerException if any of testName, reporter, stopper, or configMap
* is null.
*/
protected override def runTest(testName: String, reporter: Reporter, stopper: Stopper, configMap: Map[String, Any], tracker: Tracker) {
def invokeWithFixture(theTest: TestLeaf) {
theTest.testFun match {
case wrapper: NoArgTestWrapper[_] =>
withFixture(new FixturelessTestFunAndConfigMap(testName, wrapper.test, configMap))
case fun => withFixture(new TestFunAndConfigMap(testName, fun, configMap))
}
}
runTestImpl(thisSuite, testName, reporter, stopper, configMap, tracker, false, invokeWithFixture)
}
/**
*
* Run zero to many of this FeatureSpec'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 methodreporter - the Reporter passed to this method, or one that wraps and delegates to itstopper - the Stopper passed to this method, or one that wraps and delegates to itconfigMap - 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 itstopper - the Stopper passed to this method, or one that wraps and delegates to itconfigMap - 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 FeatureSpec.
* @param reporter the Reporter to which results will be reported
* @param stopper the Stopper that will be consulted to determine whether to stop execution early.
* @param tagsToInclude a Set of String tag names to include in the execution of this FeatureSpec
* @param tagsToExclude a Set of String tag names to exclude in the execution of this FeatureSpec
* @param configMap a Map of key-value pairs that can be used by this FeatureSpec's executing tests.
* @throws NullPointerException if any of testName, reporter, stopper, tagsToInclude,
* tagsToExclude, or configMap is null.
*/
protected override def runTests(testName: Option[String], reporter: Reporter, stopper: Stopper, filter: Filter,
configMap: Map[String, Any], distributor: Option[Distributor], tracker: Tracker) {
runTestsImpl(thisSuite, testName, reporter, stopper, filter, configMap, distributor, tracker, info, false, runTest)
}
/**
* An immutable Set of test names. If this FeatureSpec 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] = ListSet(atomic.get.testsList.map(_.testName): _*)
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], reporter: Reporter, stopper: Stopper, filter: Filter,
configMap: Map[String, Any], distributor: Option[Distributor], tracker: Tracker) {
runImpl(thisSuite, testName, reporter, stopper, filter, configMap, distributor, tracker, super.run)
}
/**
* Registers shared scenarios.
*
*
* This method enables the following syntax for shared scenarios in a FeatureSpec:
*
*
*
* scenariosFor(nonEmptyStack(lastValuePushed))
*
*
*
* This method just provides syntax sugar intended to make the intent of the code clearer.
* Because the parameter passed to it is
* type Unit, the expression will be evaluated before being passed, which
* is sufficient to register the shared scenarios. For examples of shared scenarios, see the
* Shared scenarios section in the main documentation for
* trait FeatureSpec.
*
*/
protected def scenariosFor(unit: Unit) {}
/**
* 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
}
// I need this implicit because the function is passed to scenario as the 2nd parameter list, and
// I can't overload on that. I could if I took the ScenarioWord approach, but that has possibly a worse
// downside of people could just say scenario("...") and nothing else.
/**
* 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.FeatureSpec"
}