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/*
 * Copyright 2001-2011 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

import scala.collection.immutable.ListSet
import java.util.ConcurrentModificationException
import java.util.concurrent.atomic.AtomicReference
import org.scalatest.exceptions.StackDepthExceptionHelper.getStackDepth
import org.scalatest.events._
import Suite.anErrorThatShouldCauseAnAbort
import Suite.checkRunTestParamsForNull

/**
 * A suite of tests in which each test is represented as a function value. The “Fun” in FunSuite stands
 * for “function.” Here's an example FunSuite:
 *
 * 
 * import org.scalatest.FunSuite
 *
 * class ExampleSuite extends FunSuite {
 *
 *   test("addition") {
 *     val sum = 1 + 1
 *     assert(sum === 2)
 *   }
 *
 *   test("subtraction") {
 *     val diff = 4 - 1
 *     assert(diff === 3)
 *   }
 * }
 * 
 *
 * 

 * “test” is a method, defined in FunSuite, which will be invoked
 * by the primary constructor of ExampleSuite. You specify the name of the test as
 * a string between the parentheses, and the test code itself between curly braces.
 * The test code is a function passed as a by-name parameter to test, which registers
 * it for later execution. One benefit of FunSuite compared to Suite is you need not name all your
 * tests starting with “test.” In addition, you can more easily give long names to
 * your tests, because you need not encode them in camel case.
 * 
 *
 * 

 * A FunSuite's lifecycle has two phases: the registration phase and the
 * ready phase. It starts in registration phase and enters ready phase the first time
 * run is called on it. It then remains in ready phase for the remainder of its lifetime.
 * 
 *
 * 

 * Tests can only be registered with the test method while the FunSuite is
 * in its registration phase. Any attempt to register a test after the FunSuite has
 * entered its ready phase, i.e., after run has been invoked on the FunSuite,
 * will be met with a thrown TestRegistrationClosedException. The recommended style
 * of using FunSuite is to register tests during object construction as is done in all
 * the examples shown here. If you keep to the recommended style, you should never see a
 * TestRegistrationClosedException.
 * 
 *
 * 

 * See also: Getting started with FunSuite.
 * 
 * 
 * 
Ignored tests
 *
 * 

 * To support the common use case of “temporarily” disabling a test, with the
 * good intention of resurrecting the test at a later time, FunSuite provides registration
 * methods that start with ignore instead of test. For example, to temporarily
 * disable the test named addition, just change “test” into “ignore,” like this:
 * 
 *
 * 
 * import org.scalatest.FunSuite
 *
 * class ExampleSuite extends FunSuite {
 *
 *   ignore("addition") {
 *     val sum = 1 + 1
 *     assert(sum === 2)
 *   }
 *
 *   test("subtraction") {
 *     val diff = 4 - 1
 *     assert(diff === 3)
 *   }
 * }
 * 
 *
 * 

 * If you run this version of ExampleSuite with:
 * 
 *
 * 
 * scala> (new ExampleSuite).execute()
 * 
 *
 * 

 * It will run only subtraction and report that addition was ignored:
 * 
 *
 * 
 * ExampleSuite:
 * - addition !!! IGNORED !!!
 * - subtraction
 * 
 *
 * 
Informers
 *
 * 

 * One of the parameters to the run method is a Reporter, which
 * will collect and report information about the running suite of tests.
 * Information about suites and tests that were run, whether tests succeeded or failed, 
 * and tests that were ignored will be passed to the Reporter as the suite runs.
 * Most often the reporting done by default by FunSuite's methods will be sufficient, but
 * occasionally you may wish to provide custom information to the Reporter from a test.
 * For this purpose, an Informer that will forward information to the current Reporter
 * is provided via the info parameterless method.
 * You can pass the extra information to the Informer via one of its apply methods.
 * The Informer will then pass the information to the Reporter via an InfoProvided event.
 * Here's an example:
 * 
 *
 * 
 * import org.scalatest.FunSuite
 *
 * class ExampleSuite extends FunSuite {
 *
 *   test("addition") {
 *     val sum = 1 + 1
 *     assert(sum === 2)
 *     assert(sum + 2 === 4)
 *     info("Addition seems to work")
 *   }
 * }
 * 
 *
 * If you run this FunSuite from the interpreter, you will see the following message
 * included in the printed report:
 *
 * 
 * ExampleSuite:
 * - addition
 *   + Addition seems to work 
 * 
 *
 * 
Pending tests
 *
 * 

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

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

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

 * Although pending tests may be used more often in specification-style suites, such as
 * org.scalatest.FunSpec, you can also use it in FunSuite, like this:
 * 
 *
 * 
 * import org.scalatest.FunSuite
 *
 * class ExampleSuite extends FunSuite {
 *
 *   test("addition") {
 *     val sum = 1 + 1
 *     assert(sum === 2)
 *     assert(sum + 2 === 4)
 *   }
 *
 *   test("subtraction") (pending)
 * }
 * 
 *
 * 

 * (Note: "(pending)" is the body of the test. Thus the test contains just one statement, an invocation
 * of the pending method, which throws TestPendingException.)
 * If you run this version of ExampleSuite with:
 * 
 *
 * 
 * scala> (new ExampleSuite).execute()
 * 
 *
 * 

 * It will run both tests, but report that subtraction is pending. You'll see:
 * 
 *
 * 
 * ExampleSuite:
 * - addition
 * - subtraction (pending)
 * 
 * 
 * 
Tagging tests
 *
 * 

 * A FunSuite's tests may be classified into groups by tagging them with string names.
 * As with any suite, when executing a FunSuite, groups of tests can
 * optionally be included and/or excluded. To tag a FunSuite's tests,
 * you pass objects that extend abstract class org.scalatest.Tag to methods
 * that register tests, test and ignore. Class Tag takes one parameter, a string name.  If you have
 * created Java annotation interfaces for use as group names in direct subclasses of org.scalatest.Suite,
 * then you will probably want to use group names on your FunSuites that match. To do so, simply 
 * pass the fully qualified names of the Java interfaces to the Tag constructor. For example, if you've
 * defined Java annotation interfaces with fully qualified names, com.mycompany.tags.SlowTest and
 * com.mycompany.tags.DbTest, then you could
 * create matching groups for FunSuites like this:
 * 
 *
 * 
 * import org.scalatest.Tag
 *
 * object SlowTest extends Tag("com.mycompany.tags.SlowTest")
 * object DbTest extends Tag("com.mycompany.tags.DbTest")
 * 
 *
 * 

 * Given these definitions, you could place FunSuite tests into groups like this:
 * 
 *
 * 
 * import org.scalatest.FunSuite
 *
 * class ExampleSuite extends FunSuite {
 *
 *   test("addition", SlowTest) {
 *     val sum = 1 + 1
 *     assert(sum === 2)
 *   }
 *
 *   test("subtraction", SlowTest, DbTest) {
 *     val diff = 4 - 1
 *     assert(diff === 3)
 *   }
 * }
 * 
 *
 * 

 * This code marks both tests, "addition" and "subtraction," with the com.mycompany.tags.SlowTest tag, 
 * and test "subtraction" with the com.mycompany.tags.DbTest tag.
 * 
 *
 * 

 * 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 vars 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.FunSuite
 * import collection.mutable.ListBuffer
 *
 * class ExampleSuite extends FunSuite {
 * 
 *   def fixture =
 *     new {
 *       val builder = new StringBuilder("ScalaTest is ")
 *       val buffer = new ListBuffer[String]
 *     }
 * 
 *   test("easy") {
 *     val f = fixture
 *     f.builder.append("easy!")
 *     assert(f.builder.toString === "ScalaTest is easy!")
 *     assert(f.buffer.isEmpty)
 *     f.buffer += "sweet"
 *   }
 * 
 *   test("fun") {
 *     val f = fixture
 *     f.builder.append("fun!")
 *     assert(f.builder.toString === "ScalaTest is fun!")
 *     assert(f.buffer.isEmpty)
 *   }
 * }
 * 
 *
 * 

 * The “f.” in front of each use of a fixture object provides a visual indication of which objects 
 * are part of the fixture, but if you prefer, you can import the the members with “import f._” and use the names directly.
 * 
 *
 * 
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.FunSuite
 * import collection.mutable.ListBuffer
 * 
 * class ExampleSuite extends FunSuite {
 * 
 *   trait Fixture {
 *     val builder = new StringBuilder("ScalaTest is ")
 *     val buffer = new ListBuffer[String]
 *   }
 * 
 *   test("easy") {
 *     new Fixture {
 *       builder.append("easy!")
 *       assert(builder.toString === "ScalaTest is easy!")
 *       assert(buffer.isEmpty)
 *       buffer += "sweet"
 *     }
 *   }
 * 
 *   test("fun") {
 *     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 vals and mix in trait
 * OneInstancePerTest.  If you mix in OneInstancePerTest, each test
 * will be run in its own instance of the Suite, similar to the way JUnit tests are executed. Here's an example:
 * 
 *
 * 
 * import org.scalatest.FunSuite
 * import org.scalatest.OneInstancePerTest
 * import collection.mutable.ListBuffer
 * 
 * class ExampleSuite extends FunSuite with OneInstancePerTest {
 * 
 *   val builder = new StringBuilder("ScalaTest is ")
 *   val buffer = new ListBuffer[String]
 * 
 *   test("easy") {
 *     builder.append("easy!")
 *     assert(builder.toString === "ScalaTest is easy!")
 *     assert(buffer.isEmpty)
 *     buffer += "sweet"
 *   }
 * 
 *   test("fun") {
 *     builder.append("fun!")
 *     assert(builder.toString === "ScalaTest is fun!")
 *     assert(buffer.isEmpty)
 *   }
 * }
 * 
 *
 * 

 * 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.FunSuite
 * import org.scalatest.BeforeAndAfter
 * import collection.mutable.ListBuffer
 * 
 * class ExampleSuite extends FunSuite with BeforeAndAfter {
 * 
 *   val builder = new StringBuilder
 *   val buffer = new ListBuffer[String]
 * 
 *   before {
 *     builder.append("ScalaTest is ")
 *   }
 * 
 *   after {
 *     builder.clear()
 *     buffer.clear()
 *   }
 * 
 *   test("easy") {
 *     builder.append("easy!")
 *     assert(builder.toString === "ScalaTest is easy!")
 *     assert(buffer.isEmpty)
 *     buffer += "sweet"
 *   }
 * 
 *   test("fun") {
 *     builder.append("fun!")
 *     assert(builder.toString === "ScalaTest is fun!")
 *     assert(buffer.isEmpty)
 *   }
 * }
 * 
 * 
 * 
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, which is inherited by this trait, 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.FunSuite
 * import collection.mutable.ListBuffer
 *
 * class ExampleSuite extends FunSuite {
 *
 *   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()
 *     }
 *   }
 *
 *   test("easy") {
 *     builder.append("easy!")
 *     assert(builder.toString === "ScalaTest is easy!")
 *     assert(buffer.isEmpty)
 *     buffer += "sweet"
 *   }
 *
 *   test("fun") {
 *     builder.append("fun!")
 *     assert(builder.toString === "ScalaTest is fun!")
 *     assert(buffer.isEmpty)
 *     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 fixture.FunSuite (from the org.scalatest.fixture package) instead of
 * FunSuite. Each test in a fixture.FunSuite 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
 * import java.io.FileWriter
 * import java.io.File
 * 
 * class ExampleSuite extends fixture.FunSuite {
 * 
 *   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
 *     }
 *   }
 * 
 *   test("easy") { writer =>
 *     writer.write("Hello, test!")
 *     writer.flush()
 *     assert(new File(tmpFile).length === 12)
 *   }
 * 
 *   test("fun") { writer =>
 *     writer.write("Hi, test!")
 *     writer.flush()
 *     assert(new File(tmpFile).length === 9)
 *   }
 * }
 * 
 *
 * 

 * For more information, see the documentation for fixture.FunSuite.
 * 
 *
 * 
Providing different fixtures to different tests
 * 
 * 

 * If different tests in the same FunSuite 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.FunSuite
 * 
 * class ExampleSuite extends FunSuite {
 * 
 *   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
 *     }
 *   }
 * 
 *   test("productive") { // This test needs the StringBuilder fixture
 *     new Builder {
 *       builder.append("productive!")
 *       assert(builder.toString === "ScalaTest is productive!")
 *     }
 *   }
 * 
 *   test("readable") { // This test needs the ListBuffer[String] fixture
 *     new Buffer {
 *       buffer += ("readable!")
 *       assert(buffer === List("ScalaTest", "is", "readable!"))
 *     }
 *   }
 * 
 *   test("friendly") { // This test needs the FileWriter fixture
 *     withWriter { writer =>
 *       writer.write("Hello, user!")
 *       writer.flush()
 *       assert(new File(tmpFile).length === 12)
 *     }
 *   }
 * 
 *   test("clear and concise") { // 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!"))
 *     }
 *   }
 * 
 *   test("composable") { // 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, productive uses only the StringBuilder fixture, so it just instantiates
 * a new Builder, whereas readable uses only the ListBuffer fixture, so it just intantiates
 * a new Buffer. friendly 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: clear and concise needs both the StringBuilder and the
 * ListBuffer, so it instantiates a class that mixes in both fixture traits with new Builder with Buffer.
 * composable 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 fixture.FunSuite's withFixture(OneArgTest) method. fixture.FunSuite 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.
 * 
 *
 * 

 * 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:
 * 
 * 
 * 
 * test("User logs in") {
 *   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.FunSuite
 * 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 FunSuite with Builder with Buffer {
 * 
 *   test("easy") {
 *     builder.append("easy!")
 *     assert(builder.toString === "ScalaTest is easy!")
 *     assert(buffer.isEmpty)
 *     buffer += "sweet"
 *   }
 * 
 *   test("fun") {
 *     builder.append("fun!")
 *     assert(builder.toString === "ScalaTest is fun!")
 *     assert(buffer.isEmpty)
 *     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 FunSuite with Buffer with Builder
 * 
 *
 * 

 * And if you only need one fixture you mix in only that trait:
 * 
 *
 * 
 * class Example3Suite extends FunSuite 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.FunSuite
 * 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 FunSuite with Builder with Buffer {
 * 
 *   test("easy") {
 *     builder.append("easy!")
 *     assert(builder.toString === "ScalaTest is easy!")
 *     assert(buffer.isEmpty)
 *     buffer += "sweet"
 *   }
 * 
 *   test("fun") {
 *     builder.append("fun!")
 *     assert(builder.toString === "ScalaTest is fun!")
 *     assert(buffer.isEmpty)
 *     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.
 * 
 * 
 * 
Shared tests
 *
 * 

 * Sometimes you may want to run the same test code on different fixture objects. In other words, you may want to write tests that are "shared"
 * by different fixture objects.
 * To accomplish this in a FunSuite, you first place shared tests in
 * behavior functions. These behavior functions will be
 * invoked during the construction phase of any FunSuite that uses them, so that the tests they contain will
 * be registered as tests in that FunSuite.
 * For example, given this stack class:
 * 
 *
 * 
 * import scala.collection.mutable.ListBuffer
 * 
 * class Stack[T] {
 *
 *   val MAX = 10
 *   private val buf = new ListBuffer[T]
 *
 *   def push(o: T) {
 *     if (!full)
 *       buf.prepend(o)
 *     else
 *       throw new IllegalStateException("can't push onto a full stack")
 *   }
 *
 *   def pop(): T = {
 *     if (!empty)
 *       buf.remove(0)
 *     else
 *       throw new IllegalStateException("can't pop an empty stack")
 *   }
 *
 *   def peek: T = {
 *     if (!empty)
 *       buf(0)
 *     else
 *       throw new IllegalStateException("can't pop an empty stack")
 *   }
 *
 *   def full: Boolean = buf.size == MAX
 *   def empty: Boolean = buf.size == 0
 *   def size = buf.size
 *
 *   override def toString = buf.mkString("Stack(", ", ", ")")
 * }
 * 
 *
 * 

 * You may want to test the Stack class in different states: empty, full, with one item, with one item less than capacity,
 * etc. You may find you have several tests that make sense any time the stack is non-empty. Thus you'd ideally want to run
 * those same tests for three stack fixture objects: a full stack, a stack with a one item, and a stack with one item less than
 * capacity. With shared tests, you can factor these tests out into a behavior function, into which you pass the
 * stack fixture to use when running the tests. So in your FunSuite for stack, you'd invoke the
 * behavior function three times, passing in each of the three stack fixtures so that the shared tests are run for all three fixtures.
 * 
 *
 * 

 * You can define a behavior function that encapsulates these shared tests inside the FunSuite that uses them. If they are shared
 * between different FunSuites, however, you could also define them in a separate trait that is mixed into
 * each FunSuite that uses them.
 * For example, here the nonEmptyStack behavior function (in this case, a
 * behavior method) is defined in a trait along with another
 * method containing shared tests for non-full stacks:
 * 
 * 
 * 
 * import org.scalatest.FunSuite
 * 
 * trait FunSuiteStackBehaviors { this: FunSuite =>
 * 
 *   def nonEmptyStack(createNonEmptyStack: => Stack[Int], lastItemAdded: Int) {
 * 
 *     test("empty is invoked on this non-empty stack: " + createNonEmptyStack.toString) {
 *       val stack = createNonEmptyStack
 *       assert(!stack.empty)
 *     }
 * 
 *     test("peek is invoked on this non-empty stack: " + createNonEmptyStack.toString) {
 *       val stack = createNonEmptyStack
 *       val size = stack.size
 *       assert(stack.peek === lastItemAdded)
 *       assert(stack.size === size)
 *     }
 * 
 *     test("pop is invoked on this non-empty stack: " + createNonEmptyStack.toString) {
 *       val stack = createNonEmptyStack
 *       val size = stack.size
 *       assert(stack.pop === lastItemAdded)
 *       assert(stack.size === size - 1)
 *     }
 *   }
 *   
 *   def nonFullStack(createNonFullStack: => Stack[Int]) {
 *       
 *     test("full is invoked on this non-full stack: " + createNonFullStack.toString) {
 *       val stack = createNonFullStack
 *       assert(!stack.full)
 *     }
 *       
 *     test("push is invoked on this non-full stack: " + createNonFullStack.toString) {
 *       val stack = createNonFullStack
 *       val size = stack.size
 *       stack.push(7)
 *       assert(stack.size === size + 1)
 *       assert(stack.peek === 7)
 *     }
 *   }
 * }
 * 
 *
 * 

 * Given these behavior functions, you could invoke them directly, but FunSuite offers a DSL for the purpose,
 * which looks like this:
 * 
 *
 * 
 * testsFor(nonEmptyStack(stackWithOneItem, lastValuePushed))
 * testsFor(nonFullStack(stackWithOneItem))
 * 
 *
 * 

 * If you prefer to use an imperative style to change fixtures, for example by mixing in BeforeAndAfterEach and
 * reassigning a stack var in beforeEach, you could write your behavior functions
 * in the context of that var, which means you wouldn't need to pass in the stack fixture because it would be
 * in scope already inside the behavior function. In that case, your code would look like this:
 * 
 *
 * 
 * testsFor(nonEmptyStack) // assuming lastValuePushed is also in scope inside nonEmptyStack
 * testsFor(nonFullStack)
 * 
 *
 * 

 * The recommended style, however, is the functional, pass-all-the-needed-values-in style. Here's an example:
 * 
 *
 * 
 * import org.scalatest.FunSuite
 * 
 * class StackFunSuite extends FunSuite with FunSuiteStackBehaviors {
 * 
 *   // Stack fixture creation methods
 *   def emptyStack = new Stack[Int]
 *  
 *   def fullStack = {
 *     val stack = new Stack[Int]
 *     for (i <- 0 until stack.MAX)
 *       stack.push(i)
 *     stack
 *   }
 *  
 *   def stackWithOneItem = {
 *     val stack = new Stack[Int]
 *     stack.push(9)
 *     stack
 *   }
 *  
 *   def stackWithOneItemLessThanCapacity = {
 *     val stack = new Stack[Int]
 *     for (i <- 1 to 9)
 *       stack.push(i)
 *     stack
 *   }
 *  
 *   val lastValuePushed = 9
 *  
 *   test("empty is invoked on an empty stack") {
 *     val stack = emptyStack
 *     assert(stack.empty)
 *   }
 *
 *   test("peek is invoked on an empty stack") {
 *     val stack = emptyStack
 *     intercept[IllegalStateException] {
 *       stack.peek
 *     }
 *   }
 *
 *   test("pop is invoked on an empty stack") {
 *     val stack = emptyStack
 *     intercept[IllegalStateException] {
 *       emptyStack.pop
 *     }
 *   }
 *
 *   testsFor(nonEmptyStack(stackWithOneItem, lastValuePushed))
 *   testsFor(nonFullStack(stackWithOneItem))
 *
 *   testsFor(nonEmptyStack(stackWithOneItemLessThanCapacity, lastValuePushed))
 *   testsFor(nonFullStack(stackWithOneItemLessThanCapacity))
 *
 *   test("full is invoked on a full stack") {
 *     val stack = fullStack
 *     assert(stack.full)
 *   }
 *
 *   testsFor(nonEmptyStack(fullStack, lastValuePushed))
 *
 *   test("push is invoked on a full stack") {
 *     val stack = fullStack
 *     intercept[IllegalStateException] {
 *       stack.push(10)
 *     }
 *   }
 * }
 * 
 *
 * 

 * If you load these classes into the Scala interpreter (with scalatest's JAR file on the class path), and execute it,
 * you'll see:
 * 
 *
 * 
 * scala> (new StackFunSuite).execute()
 * StackFunSuite:
 * - empty is invoked on an empty stack
 * - peek is invoked on an empty stack
 * - pop is invoked on an empty stack
 * - empty is invoked on this non-empty stack: Stack(9)
 * - peek is invoked on this non-empty stack: Stack(9)
 * - pop is invoked on this non-empty stack: Stack(9)
 * - full is invoked on this non-full stack: Stack(9)
 * - push is invoked on this non-full stack: Stack(9)
 * - empty is invoked on this non-empty stack: Stack(9, 8, 7, 6, 5, 4, 3, 2, 1)
 * - peek is invoked on this non-empty stack: Stack(9, 8, 7, 6, 5, 4, 3, 2, 1)
 * - pop is invoked on this non-empty stack: Stack(9, 8, 7, 6, 5, 4, 3, 2, 1)
 * - full is invoked on this non-full stack: Stack(9, 8, 7, 6, 5, 4, 3, 2, 1)
 * - push is invoked on this non-full stack: Stack(9, 8, 7, 6, 5, 4, 3, 2, 1)
 * - full is invoked on a full stack
 * - empty is invoked on this non-empty stack: Stack(9, 8, 7, 6, 5, 4, 3, 2, 1, 0)
 * - peek is invoked on this non-empty stack: Stack(9, 8, 7, 6, 5, 4, 3, 2, 1, 0)
 * - pop is invoked on this non-empty stack: Stack(9, 8, 7, 6, 5, 4, 3, 2, 1, 0)
 * - push is invoked on a full stack
 * 
 * 
 * 

 * One thing to keep in mind when using shared tests is that in ScalaTest, each test in a suite must have a unique name.
 * If you register the same tests repeatedly in the same suite, one problem you may encounter is an exception at runtime
 * complaining that multiple tests are being registered with the same test name.
 * In a FunSuite there is no nesting construct analogous to FunSpec's describe clause.
 * Therefore, you need to do a bit of
 * extra work to ensure that the test names are unique. If a duplicate test name problem shows up in a
 * FunSuite, you'll need to pass in a prefix or suffix string to add to each test name. You can pass this string
 * the same way you pass any other data needed by the shared tests, or just call toString on the shared fixture object.
 * This is the approach taken by the previous FunSuiteStackBehaviors example.
 * 
 *
 * 

 * Given this FunSuiteStackBehaviors trait, calling it with the stackWithOneItem fixture, like this:
 * 
 *
 * 
 * testsFor(nonEmptyStack(stackWithOneItem, lastValuePushed))
 * 
 *
 * 

 * yields test names:
 * 
 *
 * 

 * 
empty is invoked on this non-empty stack: Stack(9)
 * 
peek is invoked on this non-empty stack: Stack(9)
 * 
pop is invoked on this non-empty stack: Stack(9)
 * 
 *
 * 

 * Whereas calling it with the stackWithOneItemLessThanCapacity fixture, like this:
 * 
 *
 * 
 * testsFor(nonEmptyStack(stackWithOneItemLessThanCapacity, lastValuePushed))
 * 
 *
 * 

 * yields different test names:
 * 
 *
 * 

 * 
empty is invoked on this non-empty stack: Stack(9, 8, 7, 6, 5, 4, 3, 2, 1)
 * 
peek is invoked on this non-empty stack: Stack(9, 8, 7, 6, 5, 4, 3, 2, 1)
 * 
pop is invoked on this non-empty stack: Stack(9, 8, 7, 6, 5, 4, 3, 2, 1)
 * 
 *
 * @author Bill Venners
 */
trait FunSuite extends Suite { thisSuite =>

  private final val engine = new Engine("concurrentFunSuiteMod", "FunSuite")
  import engine._

  /**
   * 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
   * FunSuite 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 specified name, optional tags, and function value that takes no arguments.
   * This method will register the test for later execution via an invocation of one of the run
   * methods. The passed test name must not have been registered previously on
   * this FunSuite instance.
   *
   * @param testName the name of the test
   * @param testTags the optional list of tags for this test
   * @param testFun the test function
   * @throws TestRegistrationClosedException if invoked after run has been invoked on this suite
   * @throws DuplicateTestNameException if a test with the same name has been registered previously
   * @throws NotAllowedException if testName had been registered previously
   * @throws NullPointerException if testName or any passed test tag is null
   */
  protected def test(testName: String, testTags: Tag*)(testFun: => Unit) {
    registerTest(testName, testFun _, "testCannotAppearInsideAnotherTest", "FunSuite.scala", "test", 2, None, None, testTags: _*)
  }

  /**
   * Register a test to ignore, which has the specified name, optional tags, and function value that takes no arguments.
   * This method will register the test for later ignoring via an invocation of one of the run
   * methods. This method exists to make it easy to ignore an existing test by changing the call to test
   * to ignore without deleting or commenting out the actual test code. The test will not be run, but a
   * report will be sent that indicates the test was ignored. The passed test name must not have been registered previously on
   * this FunSuite instance.
   *
   * @param testName the name of the test
   * @param testTags the optional list of tags for this test
   * @param testFun the test function
   * @throws TestRegistrationClosedException if invoked after run has been invoked on this suite
   * @throws DuplicateTestNameException if a test with the same name has been registered previously
   * @throws NotAllowedException if testName had been registered previously
   */
  protected def ignore(testName: String, testTags: Tag*)(testFun: => Unit) {
    registerIgnoredTest(testName, testFun _, "ignoreCannotAppearInsideATest", "FunSuite.scala", "ignore", 1, testTags: _*)
  }

  /**
  * An immutable Set of test names. If this FunSuite 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.
  * 
  */
  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: _*)
  }

  /**
   * Run a test. This trait's implementation runs the test registered with the name specified by testName.
   *
   * @param testName the name of one test to run.
   * @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 the executing Suite of tests.
   * @throws IllegalArgumentException if testName is defined but a test with that name does not exist on this FunSuite
   * @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) {
      val theConfigMap = configMap
      withFixture(
        new NoArgTest {
          def name = testName
          def apply() { theTest.testFun() }
          def configMap = theConfigMap
        }
      )
    }

    runTestImpl(thisSuite, testName, reporter, stopper, configMap, tracker, true, invokeWithFixture)
  }

  /**
   * A Map whose keys are String tag names to which tests in this FunSuite belong, and values
   * the Set of test names that belong to each tag. If this FunSuite 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 zero to many of this FunSuite's tests.
   *
   * @param 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.
   * @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 filter a Filter with which to filter tests based on their tags
   * @param configMap a Map of key-value pairs that can be used by the executing Suite of tests.
   * @param distributor an optional Distributor, into which to put nested Suites to be run
   *              by another entity, such as concurrently by a pool of threads. If None, nested Suites will be run sequentially.
   * @param tracker a Tracker tracking Ordinals being fired by the current thread.
   * @throws NullPointerException if any of the passed parameters is null.
   * @throws IllegalArgumentException if testName is defined, but no test with the specified test name
   *     exists in this Suite
   */
  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, true, runTest)
  }

  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 tests.
   *
   * 

   * This method enables the following syntax for shared tests in a FunSuite:
   * 
   *
   * 
   * testsFor(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 tests. For examples of shared tests, see the
   * Shared tests section in the main documentation for this trait.
   * 
   */
  protected def testsFor(unit: Unit) {}
  
  /**
   * Suite style name.
   */
  final override val styleName: String = "org.scalatest.FunSuite"
}

private[scalatest] object FunSuite {
  val IgnoreTagName = "org.scalatest.Ignore"
}