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/*
* Copyright 2001-2008 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 verb.{CanVerb, ResultOfAfterWordApplication, ShouldVerb, BehaveWord,
MustVerb, StringVerbBlockRegistration}
import NodeFamily._
import scala.collection.immutable.ListSet
import org.scalatest.exceptions.StackDepthExceptionHelper.getStackDepth
import java.util.concurrent.atomic.AtomicReference
import java.util.ConcurrentModificationException
import org.scalatest.events._
import Suite.anErrorThatShouldCauseAnAbort
import Suite.autoTagClassAnnotations
/**
* Trait that facilitates a “behavior-driven” style of development (BDD), in which tests
* are combined with text that specifies the behavior the tests verify.
*
*
* Recommended Usage:
* For teams coming from specs or specs2, WordSpec
will feel familiar, and is often the most natural way to port specsN tests to
* ScalaTest. WordSpec
is very prescriptive in how text must be written, so a good fit for teams who want a high degree of discipline
* enforced upon their specification text.
*
*
*
* Trait WordSpec
is so named because you specification text is structured by placing words after strings.
* Here's an example WordSpec
:
*
*
*
* package org.scalatest.examples.wordspec
*
* import org.scalatest.WordSpec
*
* class SetSpec extends WordSpec {
*
* "A Set" when {
* "empty" should {
* "have size 0" in {
* assert(Set.empty.size === 0)
* }
*
* "produce NoSuchElementException when head is invoked" in {
* intercept[NoSuchElementException] {
* Set.empty.head
* }
* }
* }
* }
* }
*
*
*
* In a WordSpec
you write a one (or more) sentence specification for each bit of behavior you wish to
* specify and test. Each specification sentence has a
* "subject," which is sometimes called the system under test (or SUT). The
* subject is entity being specified and tested and also serves as the subject of the sentences you write for each test. A subject
* can be followed by one of three verbs, should
, must
, or can
, and a block. Here are some
* examples:
*
*
*
* "A Stack" should {
* // ...
* }
* "An Account" must {
* // ...
* }
* "A ShippingManifest" can {
* // ...
* }
*
*
*
* You can describe a subject in varying situations by using a when
clause. A when
clause
* follows the subject and precedes a block. In the block after the when
, you place strings that describe a situation or a state
* the subject may be in using a string, each followed by a verb. Here's an example:
*
*
*
* "A Stack" when {
* "empty" should {
* // ...
* }
* "non-empty" should {
* // ...
* }
* "full" should {
* // ...
* }
* }
*
*
*
* When you are ready to finish a sentence, you write a string followed by in
and a block that
* contains the code of the test. Here's an example:
*
*
*
* import org.scalatest.WordSpec
*
* class StackSpec extends WordSpec {
* "A Stack" when {
* "empty" should {
* "be empty" in {
* // ...
* }
* "complain on peek" in {
* // ...
* }
* "complain on pop" in {
* // ...
* }
* }
* "full" should {
* "be full" in {
* // ...
* }
* "complain on push" in {
* // ...
* }
* }
* }
* }
*
*
*
* Running the above StackSpec
in the interpreter would yield:
*
*
*
* scala> new StackSpec execute
* StackSpec:
* A Stack
* when empty
* - should be empty
* - should complain on peek
* - should complain on pop
* when full
* - should be full
* - should complain on push
*
*
*
* Note that the output does not exactly match the input in an effort to maximize readability.
* Although the WordSpec
code is nested, which can help you eliminate any repeated phrases
* in the specification portion of your code, the output printed moves when
and should
* down to the beginning of the next line.
*
*
*
* Sometimes you may wish to eliminate repeated phrases inside the block following a verb
. Here's an example
* in which the phrase "provide an and/or operator, which" is repeated:
*
*
*
* import org.scalatest.WordSpec
*
* class AndOrSpec extends WordSpec {
*
* "The ScalaTest Matchers DSL" should {
* "provide an and operator, which returns silently when evaluating true and true" in {}
* "provide an and operator, which throws a TestFailedException when evaluating true and false" in {}
* "provide an and operator, which throws a TestFailedException when evaluating false and true" in {}
* "provide an and operator, which throws a TestFailedException when evaluating false and false" in {}
* "provide an or operator, which returns silently when evaluating true or true" in {}
* "provide an or operator, which returns silently when evaluating true or false" in {}
* "provide an or operator, which returns silently when evaluating false or true" in {}
* "provide an or operator, which throws a TestFailedException when evaluating false or false" in {}
* }
* }
*
*
*
* In such situations you can place which
clauses inside the verb clause, like this:
*
*
*
* import org.scalatest.WordSpec
*
* class AndOrSpec extends WordSpec {
*
* "The ScalaTest Matchers DSL" should {
* "provide an and operator," which {
* "returns silently when evaluating true and true" in {}
* "throws a TestFailedException when evaluating true and false" in {}
* "throws a TestFailedException when evaluating false and true" in {}
* "throws a TestFailedException when evaluating false and false" in {}
* }
* "provide an or operator," which {
* "returns silently when evaluating true or true" in {}
* "returns silently when evaluating true or false" in {}
* "returns silently when evaluating false or true" in {}
* "throws a TestFailedException when evaluating false or false" in {}
* }
* }
* }
*
*
*
* Running the above AndOrSpec
in the interpreter would yield:
*
*
*
* scala> new AndOrSpec execute
* AndOrSpec:
* The ScalaTest Matchers DSL
* should provide an and operator, which
* - returns silently when evaluating true and true
* - throws a TestFailedException when evaluating true and false
* - throws a TestFailedException when evaluating false and true
* - throws a TestFailedException when evaluating false and false
* should provide an or operator, which
* - returns silently when evaluating true or true
* - returns silently when evaluating true or false
* - returns silently when evaluating false or true
* - throws a TestFailedException when evaluating false or false
*
*
*
* Note that unlike when
and should
/must
/can
, a which
appears
* in the output right where you put it in the input, at the end of the line, to maximize readability.
*
*
*
* If a word or phrase is repeated at the beginning of each string contained in a block, you can eliminate
* that repetition by using an after word. An after word is a word or phrase that you can place
* after when
, a verb, or
* which
. For example, in the previous WordSpec
, the word "provide" is repeated
* at the beginning of each string inside the should
block. You can factor out this duplication
* like this:
*
*
*
* import org.scalatest.WordSpec
*
* class AndOrSpec extends WordSpec {
*
* def provide = afterWord("provide")
*
* "The ScalaTest Matchers DSL" should provide {
* "an and operator," which {
* "returns silently when evaluating true and true" in {}
* "throws a TestFailedException when evaluating true and false" in {}
* "that throws a TestFailedException when evaluating false and true" in {}
* "throws a TestFailedException when evaluating false and false" in {}
* }
* "an or operator," which {
* "returns silently when evaluating true or true" in {}
* "returns silently when evaluating true or false" in {}
* "returns silently when evaluating false or true" in {}
* "throws a TestFailedException when evaluating false or false" in {}
* }
* }
* }
*
*
*
* Running the above version of AndOrSpec
with the provide
after word in the interpreter would give you:
*
*
*
* scala> new AndOrSpec execute
* AndOrSpec:
* The ScalaTest Matchers DSL
* should provide
* an and operator, which
* - returns silently when evaluating true and true
* - throws a TestFailedException when evaluating true and false
* - that throws a TestFailedException when evaluating false and true
* - throws a TestFailedException when evaluating false and false
* an or operator, which
* - returns silently when evaluating true or true
* - returns silently when evaluating true or false
* - returns silently when evaluating false or true
* - throws a TestFailedException when evaluating false or false
*
*
*
* Once you've defined an after word, you can place it after when
, a verb
* (should
, must
, or can
), or
* which
. (You can't place one after in
or is
, the
* words that introduce a test.) Here's an example that has after words used in all three
* places:
*
*
*
* import org.scalatest.WordSpec
*
* class ScalaTestGUISpec extends WordSpec {
*
* def theUser = afterWord("the user")
* def display = afterWord("display")
* def is = afterWord("is")
*
* "The ScalaTest GUI" when theUser {
* "clicks on an event report in the list box" should display {
* "a blue background in the clicked-on row in the list box" in {}
* "the details for the event in the details area" in {}
* "a rerun button," which is {
* "enabled if the clicked-on event is rerunnable" in {}
* "disabled if the clicked-on event is not rerunnable" in {}
* }
* }
* }
* }
*
*
*
* Running the previous WordSpec
in the Scala interpreter would yield:
*
*
*
* scala> new ScalaTestGUISpec execute
* ScalaTestGUISpec:
* The ScalaTest GUI
* when the user clicks on an event report in the list box
* should display
* - a blue background in the clicked-on row in the list box
* - the details for the event in the details area
* a rerun button, which is
* - enabled if the clicked-on event is rerunnable
* - disabled if the clicked-on event is not rerunnable
*
*
*
* A WordSpec
'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 while the WordSpec
is
* in its registration phase. Any attempt to register a test after the WordSpec
has
* entered its ready phase, i.e., after run
has been invoked on the WordSpec
,
* will be met with a thrown TestRegistrationClosedException
. The recommended style
* of using WordSpec
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 WordSpec
.
*
*
*
* Note: Trait WordSpec
is in part inspired by class org.specs.Specification
, designed by
* Eric Torreborre for the specs framework.
*
*
* 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, WordSpec
adds a method
* ignore
to strings that can be used instead of in
to register a test. For example, to temporarily
* disable the test with the name "A Stack should pop values in last-in-first-out order"
, just
* change “in
” into “ignore
,” like this:
*
*
*
* package org.scalatest.examples.wordspec.ignore
*
* import org.scalatest.WordSpec
*
* class SetSpec extends WordSpec {
*
* "A Set" when {
* "empty" should {
* "have size 0" ignore {
* assert(Set.empty.size === 0)
* }
*
* "produce NoSuchElementException when head is invoked" in {
* intercept[NoSuchElementException] {
* Set.empty.head
* }
* }
* }
* }
* }
*
*
*
* If you run this version of SetSpec
with:
*
*
*
* scala> new SetSpec execute
*
*
*
* It will run only the second test and report that the first test was ignored:
*
*
*
* A Set
* when empty
* - should have size 0 !!! IGNORED !!!
* - should should produce NoSuchElementException when head is invoked
*
*
*
* If you wish to temporarily ignore an entire suite of tests, you can annotate the test class with @Ignore
, like this:
*
*
*
* package org.scalatest.examples.wordspec.ignoreall
*
* import org.scalatest.WordSpec
* import org.scalatest.Ignore
*
* @Ignore
* class SetSpec extends WordSpec {
*
* "A Set" when {
* "empty" should {
* "have size 0" in {
* assert(Set.empty.size === 0)
* }
*
* "produce NoSuchElementException when head is invoked" in {
* intercept[NoSuchElementException] {
* Set.empty.head
* }
* }
* }
* }
* }
*
*
*
* When you mark a test class with a tag annotation, ScalaTest will mark each test defined in that class with that tag.
* Thus, marking the SetSpec
in the above example with the @Ignore
tag annotation means that both tests
* in the class will be ignored. If you run the above SetSpec
in the Scala interpreter, you'll see:
*
*
*
* scala> new SetSpec execute
* SetSpec:
* A Set
* when empty
* - should have size 0 !!! IGNORED !!!
* - should produce NoSuchElementException when head is invoked !!! IGNORED !!!
*
*
*
* Note that marking a test class as ignored won't prevent it from being discovered by ScalaTest. Ignored classes
* will be discovered and run, and all their tests will be reported as ignored. This is intended to keep the ignored
* class visible, to encourage the developers to eventually fix and “un-ignore” it. If you want to
* prevent a class from being discovered at all, use the DoNotDiscover
annotation instead.
*
*
*
* Informers
*
*
* One of the parameters to WordSpec
's run
method is a Reporter
, which
* will collect and report information about the running suite of tests.
* Information about suites and tests that were run, whether tests succeeded or failed,
* and tests that were ignored will be passed to the Reporter
as the suite runs.
* Most often the reporting done by default by WordSpec
'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 its apply
method.
* The Informer
will then pass the information to the Reporter
via an InfoProvided
event.
*
*
*
* One use case for the Informer
is to pass more information about a specification to the reporter. For example,
* the GivenWhenThen
trait provides methods that use the implicit info
provided by WordSpec
* to pass such information to the reporter. Here's an example:
*
*
*
* package org.scalatest.examples.wordspec.info
*
* import collection.mutable
* import org.scalatest._
*
* class SetSpec extends WordSpec with GivenWhenThen {
*
* "A mutable Set" should {
* "allow an element to be added" in {
* Given("an empty mutable Set")
* val set = mutable.Set.empty[String]
*
* When("an element is added")
* set += "clarity"
*
* Then("the Set should have size 1")
* assert(set.size === 1)
*
* And("the Set should contain the added element")
* assert(set.contains("clarity"))
*
* info("That's all folks!")
* }
* }
* }
*
*
*
* If you run this WordSpec
from the interpreter, you will see the following output:
*
*
*
* scala> new SetSpec execute
* A mutable Set
* - should allow an element to be added
* + Given an empty mutable Set
* + When an element is added
* + Then the Set should have size 1
* + And the Set should contain the added element
* + That's all folks!
*
*
* Pending tests
*
*
* A pending test is one that has been given a name but is not yet implemented. The purpose of
* pending tests is to facilitate a style of testing in which documentation of behavior is sketched
* out before tests are written to verify that behavior (and often, before the behavior of
* the system being tested is itself implemented). Such sketches form a kind of specification of
* what tests and functionality to implement later.
*
*
*
* To support this style of testing, a test can be given a name that specifies one
* bit of behavior required by the system being tested. The test can also include some code that
* sends more information about the behavior to the reporter when the tests run. At the end of the test,
* it can call method pending
, which will cause it to complete abruptly with TestPendingException
.
*
*
*
* Because tests in ScalaTest can be designated as pending with TestPendingException
, both the test name and any information
* sent to the reporter when running the test can appear in the report of a test run. (In other words,
* the code of a pending test is executed just like any other test.) However, because the test completes abruptly
* with TestPendingException
, the test will be reported as pending, to indicate
* the actual test, and possibly the functionality it is intended to test, has not yet been implemented.
* You can mark tests as pending in a WordSpec
like this:
*
*
*
* package org.scalatest.examples.wordspec.pending
*
* import org.scalatest._
*
* class SetSpec extends WordSpec {
*
* "A Set" when {
* "empty" should {
* "have size 0" in (pending)
*
* "produce NoSuchElementException when head is invoked" in {
* intercept[NoSuchElementException] {
* Set.empty.head
* }
* }
* }
* }
* }
*
*
*
* If you run this version of SetSpec
with:
*
*
*
* scala> new SetSpec execute
*
*
*
* It will run both tests but report that should have size 0
is pending. You'll see:
*
*
*
* A Set
* when empty
* - should have size 0 (pending)
* - should produce NoSuchElementException when head is invoked
*
*
*
* One difference between an ignored test and a pending one is that an ignored test is intended to be used during a
* significant refactorings of the code under test, when tests break and you don't want to spend the time to fix
* all of them immediately. You can mark some of those broken tests as ignored temporarily, so that you can focus the red
* bar on just failing tests you actually want to fix immediately. Later you can go back and fix the ignored tests.
* In other words, by ignoring some failing tests temporarily, you can more easily notice failed tests that you actually
* want to fix. By contrast, a pending test is intended to be used before a test and/or the code under test is written.
* Pending indicates you've decided to write a test for a bit of behavior, but either you haven't written the test yet, or
* have only written part of it, or perhaps you've written the test but don't want to implement the behavior it tests
* until after you've implemented a different bit of behavior you realized you need first. Thus ignored tests are designed
* to facilitate refactoring of existing code whereas pending tests are designed to facilitate the creation of new code.
*
*
*
* One other difference between ignored and pending tests is that ignored tests are implemented as a test tag that is
* excluded by default. Thus an ignored test is never executed. By contrast, a pending test is implemented as a
* test that throws TestPendingException
(which is what calling the pending
method does). Thus
* the body of pending tests are executed up until they throw TestPendingException
. The reason for this difference
* is that it enables your unfinished test to send InfoProvided
messages to the reporter before it completes
* abruptly with TestPendingException
, as shown in the previous example on Informer
s
* that used the GivenWhenThen
trait. For example, the following snippet in a WordSpec
:
*
*
*
* "The Scala language" should {
* "add correctly" in {
* Given("two integers")
* When("they are added")
* Then("the result is the sum of the two numbers")
* pending
* }
* // ...
*
*
*
* Would yield the following output when run in the interpreter:
*
*
*
* The Scala language
* - should add correctly (pending)
* + Given two integers
* + When they are added
* + Then the result is the sum of the two numbers
*
*
* Tagging tests
*
* A WordSpec
's tests may be classified into groups by tagging them with string names.
* As with any suite, when executing a WordSpec
, groups of tests can
* optionally be included and/or excluded. To tag a WordSpec
's tests,
* you pass objects that extend class org.scalatest.Tag
to methods
* that register tests. Class Tag
takes one parameter, a string name. If you have
* created tag annotation interfaces as described in the Tag
documentation, then you
* will probably want to use tag names on your test functions that match. To do so, simply
* pass the fully qualified names of the tag interfaces to the Tag
constructor. For example, if you've
* defined tag annotation interfaces with fully qualified names, com.mycompany.tags.SlowTest
and
* com.mycompany.tags.DbTest
, then you could
* create matching tags for WordSpec
s like this:
*
*
*
* package org.scalatest.examples.wordspec.tagging
*
* 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 WordSpec
tests into groups like this:
*
*
*
* import org.scalatest.WordSpec
*
* class SetSpec extends WordSpec {
*
* "A Set" when {
* "empty" should {
* "have size 0" taggedAs(SlowTest) in {
* assert(Set.empty.size === 0)
* }
*
* "produce NoSuchElementException when head is invoked" taggedAs(SlowTest, DbTest) in {
* intercept[NoSuchElementException] {
* Set.empty.head
* }
* }
* }
* }
* }
*
*
*
* This code marks both tests with the com.mycompany.tags.SlowTest
tag,
* and the second test 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.
*
*
*
* It is recommended, though not required, that you create a corresponding tag annotation when you
* create a Tag
object. A tag annotation allows you to tag all the tests of a WordSpec
in
* one stroke by annotating the class. For more information and examples, see the
* documentation for class Tag
.
*
*
* Shared fixtures
*
*
* A test fixture is composed of the objects and other artifacts (files, sockets, database
* connections, etc.) tests use to do their work.
* When multiple tests need to work with the same fixtures, it is important to try and avoid
* duplicating the fixture code across those tests. The more code duplication you have in your
* tests, the greater drag the tests will have on refactoring the actual production code.
* ScalaTest recommends several techniques to eliminate such code duplication, and provides several
* traits to help. Each technique is geared towards helping you reduce code duplication without introducing
* instance var
s, shared mutable objects, or other dependencies between tests. Eliminating shared
* mutable state across tests will make your test code easier to reason about and more amenable for parallel
* test execution.
*
*
*
* The following sections
* describe these techniques, including explaining the recommended usage
* for each. But first, here's a table summarizing the options:
*
*
*
* Technique Recommended uses
* get-fixture methods Use when you need the same mutable fixture objects in multiple tests, and don't need to clean up after.
* fixture-context objects Use when you need different combinations of mutable fixture objects in different tests, and don't need to clean up after.
* OneInstancePerTest
Use when porting JUnit tests to ScalaTest, or if you prefer JUnit's approach to test isolation: running each test in its own instance of the test class.
* withFixture(NoArgTest)
Use when you need to perform side effects at the beginning and end of all or most tests, or want to stack traits that perform such side-effects.
* loan-fixture methods Use when different tests need different fixtures that must be cleaned up afterwords.
* withFixture(OneArgTest)
Use when all or most tests need the same fixtures that must be cleaned up afterwords.
* BeforeAndAfter
Use when you need to perform the same side-effects before and/or after tests, rather than at the beginning or end of tests.
* BeforeAndAfterEach
Use when you want to stack traits that perform the same side-effects before and/or after tests, rather than at the beginning or end of tests.
*
*
*
* Calling get-fixture methods
*
*
* If you need to create the same mutable fixture objects in multiple tests, and don't need to clean them up after using them, the simplest approach is to write one or
* more get-fixture methods. A get-fixture method returns a new instance of a needed fixture object (or an holder object containing
* multiple fixture objects) each time it is called. You can call a get-fixture method at the beginning of each
* test that needs the fixture, storing the returned object or objects in local variables. Here's an example:
*
*
*
* package org.scalatest.examples.wordspec.getfixture
*
* import org.scalatest.WordSpec
* import collection.mutable.ListBuffer
*
* class ExampleSpec extends WordSpec {
*
* def fixture =
* new {
* val builder = new StringBuilder("ScalaTest is ")
* val buffer = new ListBuffer[String]
* }
*
* "Testing" should {
* "be easy" in {
* val f = fixture
* f.builder.append("easy!")
* assert(f.builder.toString === "ScalaTest is easy!")
* assert(f.buffer.isEmpty)
* f.buffer += "sweet"
* }
*
* "be fun" in {
* val f = fixture
* f.builder.append("fun!")
* assert(f.builder.toString === "ScalaTest is fun!")
* assert(f.buffer.isEmpty)
* }
* }
* }
*
*
*
* The “f.
” in front of each use of a fixture object provides a visual indication of which objects
* are part of the fixture, but if you prefer, you can import the the members with “import f._
” and use the names directly.
*
*
*
* If you need to configure fixture objects differently in different tests, you can pass configuration into the get-fixture method. For example, if you could pass
* in an initial value for a mutable fixture object as a parameter to the get-fixture method.
*
*
*
* Instantiating fixture-context objects
*
*
* An alternate technique that is especially useful when different tests need different combinations of fixture objects is to define the fixture objects as instance variables
* of fixture-context objects whose instantiation forms the body of tests. Like get-fixture methods, fixture-context objects are only
* appropriate if you don't need to clean up the fixtures after using them.
*
*
* To use this technique, you define instance variables intialized with fixture objects in traits and/or classes, then in each test instantiate an object that
* contains just the fixture objects needed by the test. Traits allow you to mix together just the fixture objects needed by each test, whereas classes
* allow you to pass data in via a constructor to configure the fixture objects. Here's an example in which fixture objects are partitioned into two traits
* and each test just mixes together the traits it needs:
*
*
*
* package org.scalatest.examples.wordspec.fixturecontext
*
* import collection.mutable.ListBuffer
* import org.scalatest.WordSpec
*
* class ExampleSpec extends WordSpec {
*
* trait Builder {
* val builder = new StringBuilder("ScalaTest is ")
* }
*
* trait Buffer {
* val buffer = ListBuffer("ScalaTest", "is")
* }
*
* "Testing" should {
* // This test needs the StringBuilder fixture
* "be productive" in new Builder {
* builder.append("productive!")
* assert(builder.toString === "ScalaTest is productive!")
* }
* }
*
* "Test code" should {
* // This test needs the ListBuffer[String] fixture
* "be readable" in new Buffer {
* buffer += ("readable!")
* assert(buffer === List("ScalaTest", "is", "readable!"))
* }
*
* // This test needs both the StringBuilder and ListBuffer
* "be clear and concise" in new Builder with Buffer {
* builder.append("clear!")
* buffer += ("concise!")
* assert(builder.toString === "ScalaTest is clear!")
* assert(buffer === List("ScalaTest", "is", "concise!"))
* }
* }
* }
*
*
*
* Mixing in OneInstancePerTest
*
*
* If every test method requires the same set of
* mutable fixture objects, and none require cleanup, one other approach you can take is make them simply val
s and mix in trait
* OneInstancePerTest
. If you mix in OneInstancePerTest
, each test
* will be run in its own instance of the Suite
, similar to the way JUnit tests are executed. Here's an example:
*
*
*
* package org.scalatest.examples.wordspec.oneinstancepertest
*
* import org.scalatest._
* import collection.mutable.ListBuffer
*
* class ExampleSuite extends WordSpec with OneInstancePerTest {
*
* val builder = new StringBuilder("ScalaTest is ")
* val buffer = new ListBuffer[String]
*
* "Testing" should {
* "be easy" in {
* builder.append("easy!")
* assert(builder.toString === "ScalaTest is easy!")
* assert(buffer.isEmpty)
* buffer += "sweet"
* }
*
* "be fun" in {
* builder.append("fun!")
* assert(builder.toString === "ScalaTest is fun!")
* assert(buffer.isEmpty)
* }
* }
* }
*
*
*
* One way to think of OneInstancePerTest
is that the entire Suite
instance is like a fixture-context object,
* but with the difference that the test code doesn't run during construction as it does with the real fixture-context object technique. Because this trait emulates JUnit's manner
* of running tests, this trait can be helpful when porting JUnit tests to ScalaTest. The primary intended use of OneInstancePerTest
is to serve as a supertrait for
* ParallelTestExecution
and the path traits, but you can also mix it in
* directly to help you port JUnit tests to ScalaTest or if you prefer JUnit's approach to test isolation.
*
*
*
* Overriding withFixture(NoArgTest)
*
*
* Although the get-fixture method, fixture-context object, and OneInstancePerTest
approaches take care of setting up a fixture at the beginning of each
* test, they don't address the problem of cleaning up a fixture at the end of the test. If you just need to perform a side-effect at the beginning or end of
* a test, and don't need to actually pass any fixture objects into the test, you can override withFixture(NoArgTest)
, one of ScalaTest's
* lifecycle methods defined in trait Suite
.
*
*
*
* Trait Suite
's implementation of runTest
passes a no-arg test function to withFixture(NoArgTest)
. It is withFixture
's
* responsibility to invoke that test function. Suite
's implementation of withFixture
simply
* invokes the function, like this:
*
*
*
* // Default implementation in trait Suite
* protected def withFixture(test: NoArgTest) {
* test()
* }
*
*
*
* You can, therefore, override withFixture
to perform setup before and/or cleanup after invoking the test function. If
* you have cleanup to perform, you should invoke the test function inside a try
block and perform the cleanup in
* a finally
clause, because the exception that causes a test to fail will propagate through withFixture
back
* to runTest
. (In other words, if the test fails, the test function invoked by withFixture
will throw an exception.)
*
*
*
* The withFixture
method is designed to be stacked, and to enable this, you should always call the super
implementation
* of withFixture
, and let it invoke the test function rather than invoking the test function directly. In other words, instead of writing
* “test()
”, you should write “super.withFixture(test)
”, like this:
*
*
*
* // Your implementation
* override def withFixture(test: NoArgTest) {
* // Perform setup
* try super.withFixture(test) // Invoke the test function
* finally {
* // Perform cleanup
* }
* }
*
*
*
* Here's an example in which withFixture(NoArgTest)
is used to take a snapshot of the working directory if a test fails, and
* and send that information to the reporter:
*
*
*
* package org.scalatest.examples.wordspec.noargtest
*
* import java.io.File
* import org.scalatest.WordSpec
*
* class ExampleSpec extends WordSpec {
*
* override def withFixture(test: NoArgTest) {
*
* try super.withFixture(test)
* catch {
* case e: Exception =>
* val currDir = new File(".")
* val fileNames = currDir.list()
* info("Dir snapshot: " + fileNames.mkString(", "))
* throw e
* }
* }
*
* "This test" should {
* "succeed" in {
* assert(1 + 1 === 2)
* }
*
* "fail" in {
* assert(1 + 1 === 3)
* }
* }
* }
*
*
*
* Running this version of ExampleSuite
in the interpreter in a directory with two files, hello.txt
and world.txt
* would give the following output:
*
*
*
* scala> new ExampleSuite execute
* ExampleSuite:
* This test
* - should succeed
* - should fail *** FAILED ***
* 2 did not equal 3 (:33)
* + Dir snapshot: hello.txt, world.txt
*
*
*
* Note that the NoArgTest
passed to withFixture
, in addition to
* an apply
method that executes the test, also includes the test name and the config
* map passed to runTest
. Thus you can also use the test name and configuration objects in your withFixture
* implementation.
*
*
*
* Calling loan-fixture methods
*
*
* If you need to both pass a fixture object into a test and perform cleanup at the end of the test, you'll need to use the loan pattern.
* If different tests need different fixtures that require cleanup, you can implement the loan pattern directly by writing loan-fixture methods.
* A loan-fixture method takes a function whose body forms part or all of a test's code. It creates a fixture, passes it to the test code by invoking the
* function, then cleans up the fixture after the function returns.
*
*
*
* The following example shows three tests that use two fixtures, a database and a file. Both require cleanup after, so each is provided via a
* loan-fixture method. (In this example, the database is simulated with a StringBuffer
.)
*
*
*
* import java.util.concurrent.ConcurrentHashMap
*
* object DbServer { // Simulating a database server
* type Db = StringBuffer
* private val databases = new ConcurrentHashMap[String, Db]
* def createDb(name: String): Db = {
* val db = new StringBuffer
* databases.put(name, db)
* db
* }
* def removeDb(name: String) {
* databases.remove(name)
* }
* }
*
* import org.scalatest.WordSpec
* import DbServer._
* import java.util.UUID.randomUUID
* import java.io._
*
* class ExampleSpec extends WordSpec {
*
* def withDatabase(testCode: Db => Any) {
* val dbName = randomUUID.toString
* val db = createDb(dbName) // create the fixture
* try {
* db.append("ScalaTest is ") // perform setup
* testCode(db) // "loan" the fixture to the test
* }
* finally removeDb(dbName) // clean up the fixture
* }
*
* def withFile(testCode: (File, FileWriter) => Any) {
* val file = File.createTempFile("hello", "world") // create the fixture
* val writer = new FileWriter(file)
* try {
* writer.write("ScalaTest is ") // set up the fixture
* testCode(file, writer) // "loan" the fixture to the test
* }
* finally writer.close() // clean up the fixture
* }
*
* "Testing" should {
* // This test needs the file fixture
* "be productive" in withFile { (file, writer) =>
* writer.write("productive!")
* writer.flush()
* assert(file.length === 24)
* }
* }
*
* "Test code" should {
* // This test needs the database fixture
* "be readable" in withDatabase { db =>
* db.append("readable!")
* assert(db.toString === "ScalaTest is readable!")
* }
*
* // This test needs both the file and the database
* "be clear and concise" in withDatabase { db =>
* withFile { (file, writer) => // loan-fixture methods compose
* db.append("clear!")
* writer.write("concise!")
* writer.flush()
* assert(db.toString === "ScalaTest is clear!")
* assert(file.length === 21)
* }
* }
* }
* }
*
*
*
* As demonstrated by the last test, loan-fixture methods compose. Not only do loan-fixture methods allow you to
* give each test the fixture it needs, they allow you to give a test multiple fixtures and clean everything up afterwords.
*
*
*
* Also demonstrated in this example is the technique of giving each test its own "fixture sandbox" to play in. When your fixtures
* involve external side-effects, like creating files or databases, it is a good idea to give each file or database a unique name as is
* done in this example. This keeps tests completely isolated, allowing you to run them in parallel if desired.
*
*
*
*
* Overriding withFixture(OneArgTest)
*
*
* If all or most tests need the same fixture, you can avoid some of the boilerplate of the loan-fixture method approach by using a fixture.Suite
* and overriding withFixture(OneArgTest)
.
* Each test in a fixture.Suite
takes a fixture as a parameter, allowing you to pass the fixture into
* the test. You must indicate the type of the fixture parameter by specifying FixtureParam
, and implement a
* withFixture
method that takes a OneArgTest
. This withFixture
method is responsible for
* invoking the one-arg test function, so you can perform fixture set up before, and clean up after, invoking and passing
* the fixture into the test function.
*
* To enable the stacking of traits that define withFixture(NoArgTest)
, it is a good idea to let
* withFixture(NoArgTest)
invoke the test function instead of invoking the test
* function directly. To do so, you'll need to convert the OneArgTest
to a NoArgTest
. You can do that by passing
* the fixture object to the toNoArgTest
method of OneArgTest
. In other words, instead of
* writing “test(theFixture)
”, you'd delegate responsibility for
* invoking the test function to the withFixture(NoArgTest)
method of the same instance by writing:
*
* withFixture(test.toNoArgTest(theFixture)) ** *
* Here's a complete example: *
* ** package org.scalatest.examples.wordspec.oneargtest * * import org.scalatest.fixture * import java.io._ * * class ExampleSpec extends fixture.WordSpec { * * case class F(file: File, writer: FileWriter) * type FixtureParam = F * * def withFixture(test: OneArgTest) { * val file = File.createTempFile("hello", "world") // create the fixture * val writer = new FileWriter(file) * try { * writer.write("ScalaTest is ") // set up the fixture * withFixture(test.toNoArgTest(F(file, writer))) // "loan" the fixture to the test * } * finally writer.close() // clean up the fixture * } * * "Testing" should { * "be easy" in { f => * f.writer.write("easy!") * f.writer.flush() * assert(f.file.length === 18) * } * * "be fun" in { f => * f.writer.write("fun!") * f.writer.flush() * assert(f.file.length === 17) * } * } * } ** *
* In this example, the tests actually required two fixture objects, a File
and a FileWriter
. In such situations you can
* simply define the FixtureParam
type to be a tuple containing the objects, or as is done in this example, a case class containing
* the objects. For more information on the withFixture(OneArgTest)
technique, see the documentation for fixture.Suite
.
*
Mixing in BeforeAndAfter
*
*
* In all the shared fixture examples shown so far, the activities of creating, setting up, and cleaning up the fixture objects have been
* performed during the test. This means that if an exception occurs during any of these activities, it will be reported as a test failure.
* Sometimes, however, you may want setup to happen before the test starts, and cleanup after the test has completed, so that if an
* exception occurs during setup or cleanup, the entire suite aborts and no more tests are attempted. The simplest way to accomplish this in ScalaTest is
* to mix in trait BeforeAndAfter
. With this trait you can denote a bit of code to run before each test
* with before
and/or after each test each test with after
, like this:
*
* package org.scalatest.examples.wordspec.beforeandafter * * import org.scalatest.WordSpec * import org.scalatest.BeforeAndAfter * import collection.mutable.ListBuffer * * class ExampleSpec extends WordSpec with BeforeAndAfter { * * val builder = new StringBuilder * val buffer = new ListBuffer[String] * * before { * builder.append("ScalaTest is ") * } * * after { * builder.clear() * buffer.clear() * } * * "Testing" should { * "be easy" in { * builder.append("easy!") * assert(builder.toString === "ScalaTest is easy!") * assert(buffer.isEmpty) * buffer += "sweet" * } * * "be fun" in { * builder.append("fun!") * assert(builder.toString === "ScalaTest is fun!") * assert(buffer.isEmpty) * } * } * } ** *
* Note that the only way before
and after
code can communicate with test code is via some side-effecting mechanism, commonly by
* reassigning instance var
s or by changing the state of mutable objects held from instance val
s (as in this example). If using
* instance var
s or mutable objects held from instance val
s you wouldn't be able to run tests in parallel in the same instance
* of the test class unless you synchronized access to the shared, mutable state. This is why ScalaTest's ParallelTestExecution
trait extends
* OneInstancePerTest
. By running each test in its own instance of the class, each test has its own copy of the instance variables, so you
* don't need to synchronize. If you mixed ParallelTestExecution
into the ExampleSuite
above, the tests would run in parallel just fine
* without any synchronization needed on the mutable StringBuilder
and ListBuffer[String]
objects.
*
* Although BeforeAndAfter
provides a minimal-boilerplate way to execute code before and after tests, it isn't designed to enable stackable
* traits, because the order of execution would be non-obvious. If you want to factor out before and after code that is common to multiple test suites, you
* should use trait BeforeAndAfterEach
instead, as shown later in the next section,
* composing fixtures by stacking traits.
*
Composing fixtures by stacking traits
* *
* In larger projects, teams often end up with several different fixtures that test classes need in different combinations,
* and possibly initialized (and cleaned up) in different orders. A good way to accomplish this in ScalaTest is to factor the individual
* fixtures into traits that can be composed using the stackable trait pattern. This can be done, for example, by placing
* withFixture
methods in several traits, each of which call super.withFixture
. Here's an example in
* which the StringBuilder
and ListBuffer[String]
fixtures used in the previous examples have been
* factored out into two stackable fixture traits named Builder
and Buffer
:
*
* package org.scalatest.examples.wordspec.composingwithfixture * * import org.scalatest._ * import collection.mutable.ListBuffer * * trait Builder extends SuiteMixin { this: Suite => * * val builder = new StringBuilder * * abstract override def withFixture(test: NoArgTest) { * builder.append("ScalaTest is ") * try super.withFixture(test) // To be stackable, must call super.withFixture * finally builder.clear() * } * } * * trait Buffer extends SuiteMixin { this: Suite => * * val buffer = new ListBuffer[String] * * abstract override def withFixture(test: NoArgTest) { * try super.withFixture(test) // To be stackable, must call super.withFixture * finally buffer.clear() * } * } * * class ExampleSpec extends WordSpec with Builder with Buffer { * * "Testing" should { * "be easy" in { * builder.append("easy!") * assert(builder.toString === "ScalaTest is easy!") * assert(buffer.isEmpty) * buffer += "sweet" * } * * "be fun" in { * builder.append("fun!") * assert(builder.toString === "ScalaTest is fun!") * assert(buffer.isEmpty) * buffer += "clear" * } * } * } ** *
* By mixing in both the Builder
and Buffer
traits, ExampleSuite
gets both fixtures, which will be
* initialized before each test and cleaned up after. The order the traits are mixed together determines the order of execution.
* In this case, Builder
is “super” to Buffer
. If you wanted Buffer
to be “super”
* to Builder
, you need only switch the order you mix them together, like this:
*
* class Example2Suite extends Suite with Buffer with Builder ** *
* And if you only need one fixture you mix in only that trait: *
* ** class Example3Suite extends Suite with Builder ** *
* Another way to create stackable fixture traits is by extending the BeforeAndAfterEach
* and/or BeforeAndAfterAll
traits.
* BeforeAndAfterEach
has a beforeEach
method that will be run before each test (like JUnit's setUp
),
* and an afterEach
method that will be run after (like JUnit's tearDown
).
* Similarly, BeforeAndAfterAll
has a beforeAll
method that will be run before all tests,
* and an afterAll
method that will be run after all tests. Here's what the previously shown example would look like if it
* were rewritten to use the BeforeAndAfterEach
methods instead of withFixture
:
*
* package org.scalatest.examples.wordspec.composingbeforeandaftereach * * import org.scalatest._ * import org.scalatest.BeforeAndAfterEach * import collection.mutable.ListBuffer * * trait Builder extends BeforeAndAfterEach { this: Suite => * * val builder = new StringBuilder * * override def beforeEach() { * builder.append("ScalaTest is ") * super.beforeEach() // To be stackable, must call super.beforeEach * } * * override def afterEach() { * try super.afterEach() // To be stackable, must call super.afterEach * finally builder.clear() * } * } * * trait Buffer extends BeforeAndAfterEach { this: Suite => * * val buffer = new ListBuffer[String] * * override def afterEach() { * try super.afterEach() // To be stackable, must call super.afterEach * finally buffer.clear() * } * } * * class ExampleSpec extends WordSpec with Builder with Buffer { * * "Testing" should { * "be easy" in { * builder.append("easy!") * assert(builder.toString === "ScalaTest is easy!") * assert(buffer.isEmpty) * buffer += "sweet" * } * * "be fun" in { * builder.append("fun!") * assert(builder.toString === "ScalaTest is fun!") * assert(buffer.isEmpty) * buffer += "clear" * } * } * } ** *
* To get the same ordering as withFixture
, place your super.beforeEach
call at the end of each
* beforeEach
method, and the super.afterEach
call at the beginning of each afterEach
* method, as shown in the previous example. It is a good idea to invoke super.afterEach
in a try
* block and perform cleanup in a finally
clause, as shown in the previous example, because this ensures the
* cleanup code is performed even if super.afterEach
throws an exception.
*
* The difference between stacking traits that extend BeforeAndAfterEach
versus traits that implement withFixture
is
* that setup and cleanup code happens before and after the test in BeforeAndAfterEach
, but at the beginning and
* end of the test in withFixture
. Thus if a withFixture
method completes abruptly with an exception, it is
* considered a failed test. By contrast, if any of the beforeEach
or afterEach
methods of BeforeAndAfterEach
* complete abruptly, it is considered an aborted suite, which will result in a SuiteAborted
event.
*
Shared tests
* *
* 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 WordSpec
, you first place shared tests in behavior functions.
* These behavior functions will be invoked during the construction phase of any WordSpec
that uses them, so that the tests they
* contain will be registered as tests in that WordSpec
. 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 WordSpec
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 WordSpec
that uses them. If they are shared
* between different WordSpec
s, however, you could also define them in a separate trait that is mixed into each WordSpec
* 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:
*
* trait StackBehaviors { this: WordSpec => * * def nonEmptyStack(newStack: => Stack[Int], lastItemAdded: Int) { * * "be non-empty" in { * assert(!newStack.empty) * } * * "return the top item on peek" in { * assert(newStack.peek === lastItemAdded) * } * * "not remove the top item on peek" in { * val stack = newStack * val size = stack.size * assert(stack.peek === lastItemAdded) * assert(stack.size === size) * } * * "remove the top item on pop" in { * val stack = newStack * val size = stack.size * assert(stack.pop === lastItemAdded) * assert(stack.size === size - 1) * } * } * * def nonFullStack(newStack: => Stack[Int]) { * * "not be full" in { * assert(!newStack.full) * } * * "add to the top on push" in { * val stack = newStack * 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 WordSpec
offers a DSL for the purpose,
* which looks like this:
*
* behave like nonEmptyStack(stackWithOneItem, lastValuePushed) * behave like 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:
*
* behave like nonEmptyStack // assuming lastValuePushed is also in scope inside nonEmptyStack * behave like nonFullStack ** *
* The recommended style, however, is the functional, pass-all-the-needed-values-in style. Here's an example: *
* ** class SharedTestExampleSpec extends WordSpec with StackBehaviors { * * // 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 * * "A Stack" when { * "empty" should { * "be empty" in { * assert(emptyStack.empty) * } * * "complain on peek" in { * intercept[IllegalStateException] { * emptyStack.peek * } * } * * "complain on pop" in { * intercept[IllegalStateException] { * emptyStack.pop * } * } * } * * "it contains one item" should { * behave like nonEmptyStack(stackWithOneItem, lastValuePushed) * behave like nonFullStack(stackWithOneItem) * } * * "it contains one item less than capacity" should { * behave like nonEmptyStack(stackWithOneItemLessThanCapacity, lastValuePushed) * behave like nonFullStack(stackWithOneItemLessThanCapacity) * } * * "full" should { * "be full" in { * assert(fullStack.full) * } * * behave like nonEmptyStack(fullStack, lastValuePushed) * * "complain on a push" in { * intercept[IllegalStateException] { * fullStack.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 SharedTestExampleSpec execute
* SharedTestExampleSpec:
* A Stack
* when empty
* - should be empty
* - should complain on peek
* - should complain on pop
* when it contains one item
* - should be non-empty
* - should return the top item on peek
* - should not remove the top item on peek
* - should remove the top item on pop
* - should not be full
* - should add to the top on push
* when it contains one item less than capacity
* - should be non-empty
* - should return the top item on peek
* - should not remove the top item on peek
* - should remove the top item on pop
* - should not be full
* - should add to the top on push
* when full
* - should be full
* - should be non-empty
* - should return the top item on peek
* - should not remove the top item on peek
* - should remove the top item on pop
* - should complain on a push
*
*
*
* 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. A good way to solve this problem in a WordSpec
is to make sure
* each invocation of a behavior function is in the context of a different surrounding when
,
* should
/must
/can
, or which
clause, because a test's name is the concatenation of its
* surrounding clauses and after words, followed by the "spec text".
* For example, the following code in a WordSpec
would register a test with the name "A Stack when empty should be empty"
:
*
* "A Stack" when { * "empty" should { * "be empty" in { * assert(emptyStack.empty) * } * } * } * // ... ** *
* If the "be empty"
test was factored out into a behavior function, it could be called repeatedly so long
* as each invocation of the behavior function is in the context of a different surrounding when
clauses.
*
Informer
that during test execution will forward strings passed to its
* apply
method to the current reporter. If invoked in a constructor, it
* will register the passed string for forwarding later during test execution. If invoked while this
* WordSpec
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
/**
* Returns a Documenter
that during test execution will forward strings passed to its
* apply
method to the current reporter. If invoked in a constructor, it
* will register the passed string for forwarding later during test execution. If invoked while this
* WordSpec
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 markup: Documenter = atomicDocumenter.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 WordSpec
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 methodName Caller's methodName
* @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
*/
private def registerTestToRun(specText: String, testTags: List[Tag], methodName: String, testFun: () => Unit) {
registerTest(specText, testFun, "itCannotAppearInsideAnotherIt", "WordSpec.scala", methodName, 4, -3, None, 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 WordSpec
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 methodName Caller's methodName
* @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
*/
private def registerTestToIgnore(specText: String, testTags: List[Tag], methodName: String, testFun: () => Unit) {
registerIgnoredTest(specText, testFun, "ignoreCannotAppearInsideAnIt", "WordSpec.scala", methodName, 4, -3, None, testTags: _*)
}
private def registerBranch(description: String, childPrefix: Option[String], methodName:String, stackDepth: Int, adjustment: Int, fun: () => Unit) {
registerNestedBranch(description, childPrefix, fun(), "describeCannotAppearInsideAnIt", "WordSpec.scala", methodName, stackDepth, adjustment, None)
}
/**
* Class that supports the registration of tagged tests.
*
*
* Instances of this class are returned by the taggedAs
method of
* class WordSpecStringWrapper
.
*
* For example, this method supports syntax such as the following: *
* ** "complain on peek" taggedAs(SlowTest) in { ... } * ^ ** *
* For more information and examples of this method's use, see the main documentation for trait WordSpec
.
*
* For example, this method supports syntax such as the following: *
* ** "complain on peek" taggedAs(SlowTest) is (pending) * ^ ** *
* For more information and examples of this method's use, see the main documentation for trait WordSpec
.
*
* For example, this method supports syntax such as the following: *
* ** "complain on peek" taggedAs(SlowTest) ignore { ... } * ^ ** *
* For more information and examples of this method's use, see the main documentation for trait WordSpec
.
*
convertToWordSpecStringWrapper
) enables
* methods when
, which
, in
, is
, taggedAs
* and ignore
to be invoked on String
s.
*
*
* This class provides much of the syntax for WordSpec
, however, it does not add
* the verb methods (should
, must
, and can
) to String
.
* Instead, these are added via the ShouldVerb
, MustVerb
, and CanVerb
* traits, which WordSpec
mixes in, to avoid a conflict with implicit conversions provided
* in ShouldMatchers
and MustMatchers
.
*
* For example, this method supports syntax such as the following: *
* ** "complain on peek" in { ... } * ^ ** *
* For more information and examples of this method's use, see the main documentation for trait WordSpec
.
*
* For example, this method supports syntax such as the following: *
* ** "complain on peek" ignore { ... } * ^ ** *
* For more information and examples of this method's use, see the main documentation for trait WordSpec
.
*
* For example, this method supports syntax such as the following: *
* ** "complain on peek" is (pending) * ^ ** *
* For more information and examples of this method's use, see the main documentation for trait WordSpec
.
*
* For example, this method supports syntax such as the following: *
* ** "complain on peek" taggedAs(SlowTest) in { ... } * ^ ** *
* For more information and examples of this method's use, see the main documentation for trait WordSpec
.
*
when
clause.
*
* * For example, this method supports syntax such as the following: *
* ** "A Stack" when { ... } * ^ ** *
* For more information and examples of this method's use, see the main documentation for trait WordSpec
.
*
when
clause that is followed by an after word.
*
* * For example, this method supports syntax such as the following: *
* ** val theUser = afterWord("the user") * * "A Stack" when theUser { ... } * ^ ** *
* For more information and examples of this method's use, see the main documentation for trait WordSpec
.
*
that
has been deprecated and will be used for a different purpose in a future version of ScalaTest. Please
* use which
instead. (Warning: this change will likely have a shorter than usual deprecation cycle: less than a year.)
*/
@deprecated("Please use \"which\" instead of \"that\".")
def that(f: => Unit) {
registerBranch(string.trim + " that", None, "that", 4, -2, f _)
}
/**
* Registers a which
clause.
*
* * For example, this method supports syntax such as the following: *
* ** "a rerun button" which { * ^ ** *
* For more information and examples of this method's use, see the main documentation for trait WordSpec
.
*
that
has been deprecated and will be used for a different purpose in a future version of ScalaTest. Please
* use which
instead. (Warning: this change will likely have a shorter than usual deprecation cycle: less than a year.)
*/
@deprecated("Please use \"which\" instead of \"that\".")
def that(resultOfAfterWordApplication: ResultOfAfterWordApplication) {
registerBranch(string.trim + " that " + resultOfAfterWordApplication.text.trim, None, "that", 4, -2, resultOfAfterWordApplication.f)
}
/**
* Registers a which
clause that is followed by an after word.
*
* * For example, this method supports syntax such as the following: *
* ** def is = afterWord("is") * * "a rerun button" which is { * ^ ** *
* For more information and examples of this method's use, see the main documentation for trait WordSpec
.
*
* If you are repeating a word or phrase at the beginning of each string inside
* a block, you can "move the word or phrase" out of the block with an after word.
* You create an after word by passing the repeated word or phrase to the afterWord
method.
* Once created, you can place the after word after when
, a verb
* (should
, must
, or can
), or
* which
. (You can't place one after in
or is
, the
* words that introduce a test.) Here's an example that has after words used in all three
* places:
*
* import org.scalatest.WordSpec * * class ScalaTestGUISpec extends WordSpec { * * def theUser = afterWord("the user") * def display = afterWord("display") * def is = afterWord("is") * * "The ScalaTest GUI" when theUser { * "clicks on an event report in the list box" should display { * "a blue background in the clicked-on row in the list box" in {} * "the details for the event in the details area" in {} * "a rerun button" which is { * "enabled if the clicked-on event is rerunnable" in {} * "disabled if the clicked-on event is not rerunnable" in {} * } * } * } * } ** *
* Running the previous WordSpec
in the Scala interpreter would yield:
*
* scala> (new ScalaTestGUISpec).execute()
* The ScalaTest GUI (when the user clicks on an event report in the list box)
* - should display a blue background in the clicked-on row in the list box
* - should display the details for the event in the details area
* - should display a rerun button that is enabled if the clicked-on event is rerunnable
* - should display a rerun button that is disabled if the clicked-on event is not rerunnable
*
*/
protected final class AfterWord(text: String) {
/**
* Supports the use of after words.
*
*
* This method transforms a block of code into a ResultOfAfterWordApplication
, which
* is accepted by when
, should
, must
, can
, and which
* methods. For more information, see the main documentation for trait WordSpec
.
*
* If you are repeating a word or phrase at the beginning of each string inside
* a block, you can "move the word or phrase" out of the block with an after word.
* You create an after word by passing the repeated word or phrase to the afterWord
method.
* Once created, you can place the after word after when
, a verb
* (should
, must
, or can
), or
* which
. (You can't place one after in
or is
, the
* words that introduce a test.) Here's an example that has after words used in all three
* places:
*
* import org.scalatest.WordSpec * * class ScalaTestGUISpec extends WordSpec { * * def theUser = afterWord("the user") * def display = afterWord("display") * def is = afterWord("is") * * "The ScalaTest GUI" when theUser { * "clicks on an event report in the list box" should display { * "a blue background in the clicked-on row in the list box" in {} * "the details for the event in the details area" in {} * "a rerun button" which is { * "enabled if the clicked-on event is rerunnable" in {} * "disabled if the clicked-on event is not rerunnable" in {} * } * } * } * } ** *
* Running the previous WordSpec
in the Scala interpreter would yield:
*
* scala> (new ScalaTestGUISpec).execute()
* The ScalaTest GUI (when the user clicks on an event report in the list box)
* - should display a blue background in the clicked-on row in the list box
* - should display the details for the event in the details area
* - should display a rerun button that is enabled if the clicked-on event is rerunnable
* - should display a rerun button that is disabled if the clicked-on event is not rerunnable
*
*/
protected def afterWord(text: String) = new AfterWord(text)
/**
* Implicitly converts String
s to WordSpecStringWrapper
, which enables
* methods when
, which
, in
, is
, taggedAs
* and ignore
to be invoked on String
s.
*/
protected implicit def convertToWordSpecStringWrapper(s: String) = new WordSpecStringWrapper(s)
// Used to enable should/can/must to take a block (except one that results in type string. May
// want to mention this as a gotcha.)
/*
import org.scalatest.WordSpec
class MySpec extends WordSpec {
"bla bla bla" should {
"do something" in {
assert(1 + 1 === 2)
}
"now it is a string"
}
}
delme.scala:6: error: no implicit argument matching parameter type (String, String, String) => org.scalatest.verb.ResultOfStringPassedToVerb was found.
"bla bla bla" should {
^
one error found
*/
/**
* Supports the registration of subjects.
*
* * For example, this method enables syntax such as the following: *
* ** "A Stack" should { ... * ^ ** *
* This function is passed as an implicit parameter to a should
method
* provided in ShouldVerb
, a must
method
* provided in MustVerb
, and a can
method
* provided in CanVerb
. When invoked, this function registers the
* subject and executes the block.
*
* For example, this method enables syntax such as the following: *
* ** def provide = afterWord("provide") * * "The ScalaTest Matchers DSL" can provide { ... } * ^ ** *
* This function is passed as an implicit parameter to a should
method
* provided in ShouldVerb
, a must
method
* provided in MustVerb
, and a can
method
* provided in CanVerb
. When invoked, this function registers the
* subject and executes the block.
*
Map
whose keys are String
tag names to which tests in this WordSpec
belong, and values
* the Set
of test names that belong to each tag. If this WordSpec
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
* @return a Status
object that indicates when the test started by this method has completed, and whether or not it failed .
*
* @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) {
val theConfigMap = args.configMap
val testData = testDataFor(testName, theConfigMap)
withFixture(
new NoArgTest {
val name = testData.name
def apply() { theTest.testFun() }
val configMap = testData.configMap
val scopes = testData.scopes
val text = testData.text
val tags = testData.tags
}
)
}
runTestImpl(thisSuite, testName, args, true, invokeWithFixture)
}
/**
* Run zero to many of this WordSpec
'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
- theString
value of thetestName
Option
passed * to this method
* reporter
- theReporter
passed to this method, or one that wraps and delegates to it
* stopper
- theStopper
passed to this method, or one that wraps and delegates to it
* configMap
- theconfigMap
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
Set
s.
* If so, this implementation invokes runTest
, passing in:
*
-
*
testName
- theString
name of the test to run (which will be one of the names in thetestNames
Set
)
* reporter
- theReporter
passed to this method, or one that wraps and delegates to it
* stopper
- theStopper
passed to this method, or one that wraps and delegates to it
* configMap
- theconfigMap
passed to this method, or one that wraps and delegates to it
*
None
, all relevant tests should be run.
* I.e., None
acts like a wildcard that means run all relevant tests in this Suite
.
* @param args the Args
for this run
* @return a Status
object that indicates when all tests started by this method have completed, and whether or not a failure occurred.
*
* @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], args: Args): Status = {
runTestsImpl(thisSuite, testName, args, info, true, runTest)
}
/**
* An immutable Set
of test names. If this WordSpec
contains no tests, this method returns an
* empty Set
.
*
*
* This trait's implementation of this method will return a set that contains the names of all registered tests. The set's
* iterator will return those names in the order in which the tests were registered. Each test's name is composed
* of the concatenation of the text of each surrounding describer, in order from outside in, and the text of the
* example itself, with all components separated by a space. For example, consider this WordSpec
:
*
* import org.scalatest.WordSpec * * class StackSpec { * "A Stack" when { * "not empty" must { * "allow me to pop" in {} * } * "not full" must { * "allow me to push" in {} * } * } * } ** *
* Invoking testNames
on this WordSpec
will yield a set that contains the following
* two test name strings:
*
* "A Stack (when not empty) must allow me to pop" * "A Stack (when not full) must allow me to push" **/ 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
WordSpec
s.
*
* * This field enables syntax such as the following: *
* ** behave like nonFullStack(stackWithOneItem) * ^ ** *
* For more information and examples of the use of