ShouldSyntax

This class is part of the ScalaTest matchers DSL. Please see the documentation for Matchers for an overview of the matchers DSL.

This class is part of the ScalaTest matchers DSL. Please see the documentation for Matchers for an overview of the matchers DSL.

This class is part of the ScalaTest matchers DSL. Please see the documentation for Matchers for an overview of the matchers DSL.

This class is used in conjunction with an implicit conversion to enable should methods to be invoked on objects of type Any.

Class used via an implicit conversion to enable two objects to be compared with === and !== with a Boolean result and an enforced type constraint between two object types. For example:

assert(a === b)
assert(c !== d)

You can also check numeric values against another with a tolerance. Here are some examples:

assert(a === (2.0 +- 0.1))
assert(c !== (2.0 +- 0.1))

This class is part of the Scalactic “explicitly DSL”. Please see the documentation for Explicitly for an overview of the explicitly DSL.

Instances of this class are returned via the decided by <an Equality> syntax, and enables afterBeing to be invoked on it. Here's an example, given an Equality[String] named myStringEquality:

result should equal ("hello") (decided by myStringEquality afterBeing lowerCased)

This class is part of the Scalactic “explicitly DSL”. Please see the documentation for Explicitly for an overview of the explicitly DSL.

This class is part of the Scalactic “explicitly DSL”. Please see the documentation for Explicitly for an overview of the explicitly DSL.

Instances of this class are returned via the decided by <an Equivalence> syntax, and enables afterBeing to be invoked on it. Here's an example, given an Equivalence[String] named myStringEquivalence:

result should equal ("hello") (determined by myStringEquivalence afterBeing lowerCased)

This class is part of the Scalactic “explicitly DSL”. Please see the documentation for Explicitly for an overview of the explicitly DSL.

Class used via an implicit conversion to enable any two objects to be compared with === and !== with a Boolean result and no enforced type constraint between two object types. For example:

assert(a === b)
assert(c !== d)

You can also check numeric values against another with a tolerance. Here are some examples:

assert(a === (2.0 +- 0.1))
assert(c !== (2.0 +- 0.1))

This class is part of the ScalaTest matchers DSL. Please see the documentation for Matchers for an overview of the matchers DSL.

Wrapper class with a +- method that, given a Numeric argument, returns a Spread.

This class is part of the ScalaTest matchers DSL. Please see the documentation for Matchers for an overview of the matchers DSL.

This class is part of the ScalaTest matchers DSL. Please see the documentation for Matchers for an overview of the matchers DSL.

This class is part of the ScalaTest matchers DSL. Please see the documentation for InspectorsMatchers for an overview of the matchers DSL.

This class is part of the ScalaTest matchers DSL. Please see the documentation for InspectorsMatchers for an overview of the matchers DSL.

This class is part of the ScalaTest matchers DSL. Please see the documentation for InspectorsMatchers for an overview of the matchers DSL.

This class is part of the ScalaTest matchers DSL. Please see the documentation for InspectorsMatchers for an overview of the matchers DSL.

This class is part of the ScalaTest matchers DSL. Please see the documentation for Matchers for an overview of the matchers DSL.

This class is part of the ScalaTest matchers DSL. Please see the documentation for InspectorsMatchers for an overview of the matchers DSL.

This class is part of the ScalaTest matchers DSL. Please see the documentation for Matchers for an overview of the matchers DSL.

This class is part of the ScalaTest matchers DSL. Please see the documentation for Matchers for an overview of the matchers DSL.

This class is part of the ScalaTest matchers DSL. Please see the documentation for Matchers for an overview of the matchers DSL.

This class is part of the ScalaTest matchers DSL. Please see the documentation for InspectorsMatchers for an overview of the matchers DSL.

This class is part of the ScalaTest matchers DSL. Please see the documentation for Matchers for an overview of the matchers DSL.

This class is part of the ScalaTest matchers DSL. Please see the documentation for InspectorsMatchers for an overview of the matchers DSL.

This class is part of the ScalaTest matchers DSL. Please see the documentation for InspectorsMatchers for an overview of the matchers DSL.

This class is part of the ScalaTest matchers DSL. Please see the documentation for Matchers for an overview of the matchers DSL.

This class supports the syntax of FlatSpec, WordSpec, fixture.FlatSpec, and fixture.WordSpec.

This class is used in conjunction with an implicit conversion to enable should methods to be invoked on Strings.

This class is part of the Scalactic “explicitly DSL”. Please see the documentation for Explicitly for an overview of the explicitly DSL.

This class is part of the ScalaTest matchers DSL. Please see the documentation for Matchers for an overview of the matchers DSL.

This class is part of the ScalaTest matchers DSL. Please see the documentation for Matchers for an overview of the matchers DSL.

Returns a TripleEqualsInvocationOnSpread[T], given an Spread[T], to facilitate the “<left> should !== (<pivot> +- <tolerance>)” syntax of Matchers.

Returns a TripleEqualsInvocation[Null], given a null reference, to facilitate the “<left> should !== null” syntax of Matchers.

Returns a TripleEqualsInvocation[T], given an object of type T, to facilitate the “<left> should !== <right>” syntax of Matchers.

This method enables the following syntax:

num should (not be < (10) and not be > (17))
                  ^

This method enables the following syntax:

num should (not be <= (10) and not be > (17))
                  ^

Returns a TripleEqualsInvocationOnSpread[T], given an Spread[T], to facilitate the “<left> should === (<pivot> +- <tolerance>)” syntax of Matchers.

Returns a TripleEqualsInvocation[Null], given a null reference, to facilitate the “<left> should === null” syntax of Matchers.

Returns a TripleEqualsInvocation[T], given an object of type T, to facilitate the “<left> should === <right>” syntax of Matchers.

This method enables the following syntax:

num should (not be > (10) and not be < (7))
                  ^

This method enables the following syntax:

num should (not be >= (10) and not be < (7))
                  ^

This method enables the following syntax:

a [RuntimeException] should be thrownBy { ... }
^

This method enables the following syntax for String:

all(str) should fullymatch regex ("Hel*o world".r)
^

This method enables the following syntax for java.util.Map:

all(jmap) should fullymatch regex ("Hel*o world".r)
^

This method enables the following syntax for scala.collection.GenMap:

all(map) should fullymatch regex ("Hel*o world".r)
^

This method enables the following syntax:

all(xs) should fullymatch regex ("Hel*o world".r)
^

This method enables the following syntax:

List(1, 2, 3) should contain (allElementsOf(1, 2))
                             ^

This method enables the following syntax:

List(1, 2, 3) should contain (allOf(1, 2))
                             ^

This method enables the following syntax:

an [Exception] should be thrownBy { ... }
^

Assert that a boolean condition, described in String message, is true. If the condition is true, this method returns normally. Else, it throws TestFailedException with a helpful error message appended with the String obtained by invoking toString on the specified clue as the exception's detail message.

This method is implemented in terms of a Scala macro that will generate a more helpful error message for expressions of this form:

• assert(a == b, "a good clue")

• assert(a != b, "a good clue")

• assert(a === b, "a good clue")

• assert(a !== b, "a good clue")

• assert(a > b, "a good clue")

• assert(a >= b, "a good clue")

• assert(a < b, "a good clue")

• assert(a <= b, "a good clue")

• assert(a startsWith "prefix", "a good clue")

• assert(a endsWith "postfix", "a good clue")

• assert(a contains "something", "a good clue")

• assert(a eq b, "a good clue")

• assert(a ne b, "a good clue")

• assert(a > 0 && b > 5, "a good clue")

• assert(a > 0 || b > 5, "a good clue")

• assert(a.isEmpty, "a good clue")

• assert(!a.isEmpty, "a good clue")

• assert(a.isInstanceOf[String], "a good clue")

• assert(a.length == 8, "a good clue")

• assert(a.size == 8, "a good clue")

• assert(a.exists(_ == 8), "a good clue")

At this time, any other form of expression will just get a TestFailedException with message saying the given expression was false. In the future, we will enhance this macro to give helpful error messages in more situations. In ScalaTest 2.0, however, this behavior was sufficient to allow the === that returns Boolean to be the default in tests. This makes === consistent between tests and production code.

Assert that a boolean condition is true. If the condition is true, this method returns normally. Else, it throws TestFailedException.

This method is implemented in terms of a Scala macro that will generate a more helpful error message for expressions of this form:

• assert(a == b)

• assert(a != b)

• assert(a === b)

• assert(a !== b)

• assert(a > b)

• assert(a >= b)

• assert(a < b)

• assert(a <= b)

• assert(a startsWith "prefix")

• assert(a endsWith "postfix")

• assert(a contains "something")

• assert(a eq b)

• assert(a ne b)

• assert(a > 0 && b > 5)

• assert(a > 0 || b > 5)

• assert(a.isEmpty)

• assert(!a.isEmpty)

• assert(a.isInstanceOf[String])

• assert(a.length == 8)

• assert(a.size == 8)

• assert(a.exists(_ == 8))

At this time, any other form of expression will get a TestFailedException with message saying the given expression was false. In the future, we will enhance this macro to give helpful error messages in more situations. In ScalaTest 2.0, however, this behavior was sufficient to allow the === that returns Boolean to be the default in tests. This makes === consistent between tests and production code.

Asserts that a given string snippet of code passes both the Scala parser and type checker.

You can use this to make sure a snippet of code compiles:

assertCompiles("val a: Int = 1")

Although assertCompiles is implemented with a macro that determines at compile time whether the snippet of code represented by the passed string compiles, errors (i.e., snippets of code that do not compile) are reported as test failures at runtime.

Asserts that a given string snippet of code does not pass either the Scala parser or type checker.

Often when creating libraries you may wish to ensure that certain arrangements of code that represent potential “user errors” do not compile, so that your library is more error resistant. ScalaTest's Assertions trait includes the following syntax for that purpose:

assertDoesNotCompile("val a: String = \"a string")

Although assertDoesNotCompile is implemented with a macro that determines at compile time whether the snippet of code represented by the passed string doesn't compile, errors (i.e., snippets of code that do compile) are reported as test failures at runtime.

Note that the difference between assertTypeError and assertDoesNotCompile is that assertDoesNotCompile will succeed if the given code does not compile for any reason, whereas assertTypeError will only succeed if the given code does not compile because of a type error. If the given code does not compile because of a syntax error, for example, assertDoesNotCompile will return normally but assertTypeError will throw a TestFailedException.

Assert that the value passed as expected equals the value passed as actual. If the actual value equals the expected value (as determined by ==), assertResult returns normally. Else, assertResult throws a TestFailedException whose detail message includes the expected and actual values.

Assert that the value passed as expected equals the value passed as actual. If the actual equals the expected (as determined by ==), assertResult returns normally. Else, if actual is not equal to expected, assertResult throws a TestFailedException whose detail message includes the expected and actual values, as well as the String obtained by invoking toString on the passed clue.

Ensure that an expected exception is thrown by the passed function value. The thrown exception must be an instance of the type specified by the type parameter of this method. This method invokes the passed function. If the function throws an exception that's an instance of the specified type, this method returns Succeeded. Else, whether the passed function returns normally or completes abruptly with a different exception, this method throws TestFailedException.

Note that the type specified as this method's type parameter may represent any subtype of AnyRef, not just Throwable or one of its subclasses. In Scala, exceptions can be caught based on traits they implement, so it may at times make sense to specify a trait that the intercepted exception's class must mix in. If a class instance is passed for a type that could not possibly be used to catch an exception (such as String, for example), this method will complete abruptly with a TestFailedException.

Also note that the difference between this method and intercept is that this method does not return the expected exception, so it does not let you perform further assertions on that exception. Instead, this method returns Succeeded, which means it can serve as the last statement in an async- or safe-style suite. It also indicates to the reader of the code that nothing further is expected about the thrown exception other than its type. The recommended usage is to use assertThrows by default, intercept only when you need to inspect the caught exception further.

Asserts that a given string snippet of code does not pass the Scala type checker, failing if the given snippet does not pass the Scala parser.

Often when creating libraries you may wish to ensure that certain arrangements of code that represent potential “user errors” do not compile, so that your library is more error resistant. ScalaTest's Assertions trait includes the following syntax for that purpose:

assertTypeError("val a: String = 1")

Although assertTypeError is implemented with a macro that determines at compile time whether the snippet of code represented by the passed string type checks, errors (i.e., snippets of code that do type check) are reported as test failures at runtime.

Note that the difference between assertTypeError and assertDoesNotCompile is that assertDoesNotCompile will succeed if the given code does not compile for any reason, whereas assertTypeError will only succeed if the given code does not compile because of a type error. If the given code does not compile because of a syntax error, for example, assertDoesNotCompile will return normally but assertTypeError will throw a TestFailedException.

Assume that a boolean condition, described in String message, is true. If the condition is true, this method returns normally. Else, it throws TestCanceledException with a helpful error message appended with String obtained by invoking toString on the specified clue as the exception's detail message.

This method is implemented in terms of a Scala macro that will generate a more helpful error message for expressions of this form:

• assume(a == b, "a good clue")

• assume(a != b, "a good clue")

• assume(a === b, "a good clue")

• assume(a !== b, "a good clue")

• assume(a > b, "a good clue")

• assume(a >= b, "a good clue")

• assume(a < b, "a good clue")

• assume(a <= b, "a good clue")

• assume(a startsWith "prefix", "a good clue")

• assume(a endsWith "postfix", "a good clue")

• assume(a contains "something", "a good clue")

• assume(a eq b, "a good clue")

• assume(a ne b, "a good clue")

• assume(a > 0 && b > 5, "a good clue")

• assume(a > 0 || b > 5, "a good clue")

• assume(a.isEmpty, "a good clue")

• assume(!a.isEmpty, "a good clue")

• assume(a.isInstanceOf[String], "a good clue")

• assume(a.length == 8, "a good clue")

• assume(a.size == 8, "a good clue")

• assume(a.exists(_ == 8), "a good clue")

At this time, any other form of expression will just get a TestCanceledException with message saying the given expression was false. In the future, we will enhance this macro to give helpful error messages in more situations. In ScalaTest 2.0, however, this behavior was sufficient to allow the === that returns Boolean to be the default in tests. This makes === consistent between tests and production code.

Assume that a boolean condition is true. If the condition is true, this method returns normally. Else, it throws TestCanceledException.

This method is implemented in terms of a Scala macro that will generate a more helpful error message for expressions of this form:

• assume(a == b)

• assume(a != b)

• assume(a === b)

• assume(a !== b)

• assume(a > b)

• assume(a >= b)

• assume(a < b)

• assume(a <= b)

• assume(a startsWith "prefix")

• assume(a endsWith "postfix")

• assume(a contains "something")

• assume(a eq b)

• assume(a ne b)

• assume(a > 0 && b > 5)

• assume(a > 0 || b > 5)

• assume(a.isEmpty)

• assume(!a.isEmpty)

• assume(a.isInstanceOf[String])

• assume(a.length == 8)

• assume(a.size == 8)

• assume(a.exists(_ == 8))

At this time, any other form of expression will just get a TestCanceledException with message saying the given expression was false. In the future, we will enhance this macro to give helpful error messages in more situations. In ScalaTest 2.0, however, this behavior was sufficient to allow the === that returns Boolean to be the default in tests. This makes === consistent between tests and production code.

This method enables the following syntax for String:

atLeast(1, str) should fullymatch regex ("Hel*o world".r)
^

This method enables the following syntax for java.util.Map:

atLeast(1, jmap) should fullymatch regex ("Hel*o world".r)
^

This method enables the following syntax for scala.collection.GenMap:

atLeast(1, map) should fullymatch regex ("Hel*o world".r)
^

This method enables the following syntax:

atLeast(1, xs) should fullymatch regex ("Hel*o world".r)
^

This method enables the following syntax:

List(1, 2, 3) should contain (atLeastOneElementOf (List(1, 2)))
                             ^

This method enables the following syntax:

List(1, 2, 3) should contain (atLeastOneOf(1, 2))
                             ^

This method enables the following syntax for String:

atMost(3, str) should fullymatch regex ("Hel*o world".r)
^

This method enables the following syntax for java.util.Map:

atMost(3, jmap) should fullymatch regex ("Hel*o world".r)
^

This method enables the following syntax for scala.collection.GenMap:

atMost(3, map) should fullymatch regex ("Hel*o world".r)
^

This method enables the following syntax:

atMost(3, xs) should fullymatch regex ("Hel*o world".r)
^

This method enables the following syntax:

List(1, 2, 3) should contain (atMostOneElementOf (List(1, 2)))
                             ^

This method enables the following syntax:

List(1, 2, 3) should contain (atMostOneOf(1, 2))
                             ^

This method enables the following syntax for String:

between(1, 3, str) should fullymatch regex ("Hel*o world".r)
^

This method enables the following syntax for java.util.Map:

between(1, 3, jmap) should fullymatch regex ("Hel*o world".r)
^

This method enables the following syntax:

between(1, 3, xs) should fullymatch regex ("Hel*o world".r)
^

Throws TestCanceledException, with the passed Throwable cause, to indicate a test failed. The getMessage method of the thrown TestCanceledException will return cause.toString.

Throws TestCanceledException, with the passed String message as the exception's detail message and Throwable cause, to indicate a test failed.

Throws TestCanceledException, with the passed String message as the exception's detail message, to indicate a test was canceled.

Throws TestCanceledException to indicate a test was canceled.

Provides a A CanEqual B for any two types A and B, enforcing the type constraint that A must be a subtype of B, given an explicit Equivalence[B].

This method is used to enable the Explicitly DSL for TypeCheckedTripleEquals by requiring an explicit Equivalance[B], but taking an implicit function that provides evidence that A is a subtype of B.

The returned Constraint's areEqual method uses the implicitly passed Equivalence[B]'s areEquivalent method to determine equality.

This method is overridden and made implicit by subtraits LowPriorityTypeCheckedConstraint (extended by TypeCheckedTripleEquals), and overriden as non-implicit by the other subtraits in this package.

Provides an A CanEqual B instance for any two types A and B, enforcing the type constraint that B must be a subtype of A, given an explicit Equivalence[A].

This method is used to enable the Explicitly DSL for TypeCheckedTripleEquals by requiring an explicit Equivalance[B], but taking an implicit function that provides evidence that A is a subtype of B. For example, under TypeCheckedTripleEquals, this method (as an implicit method), would be used to compile this statement:

def closeEnoughTo1(num: Double): Boolean =
 (num === 1.0)(decided by forgivingEquality)

The returned Constraint's areEqual method uses the implicitly passed Equivalence[A]'s areEquivalent method to determine equality.

This method is overridden and made implicit by subtraits TypeCheckedTripleEquals) and overriden as non-implicit by the other subtraits in this package.

Converts to an CheckingEqualizer that provides === and !== operators that result in Boolean and enforce a type constraint.

This method is overridden and made implicit by subtrait TypeCheckedTripleEquals, and overriden as non-implicit by the other subtraits in this package.

Returns an Equality[A] for any type A that determines equality by first calling .deep on any Array (on either the left or right side), then comparing the resulting objects with ==.

This method enables the following syntax:

list should (not be definedAt (7) and not be definedAt (9))
                   ^

This method enables syntax such as the following:

result should equal (null)
             ^

This method enables syntax such as the following:

result should equal (100 +- 1)
             ^

This method enables the following syntax:

result should equal (7)
             ^

The left should equal (right) syntax works by calling == on the left value, passing in the right value, on every type except arrays. If both left and right are arrays, deep will be invoked on both left and right before comparing them with ==. Thus, even though this expression will yield false, because Array's equals method compares object identity:

Array(1, 2) == Array(1, 2) // yields false

The following expression will not result in a TestFailedException, because ScalaTest will compare the two arrays structurally, taking into consideration the equality of the array's contents:

Array(1, 2) should equal (Array(1, 2)) // succeeds (i.e., does not throw TestFailedException)

If you ever do want to verify that two arrays are actually the same object (have the same identity), you can use the be theSameInstanceAs syntax.

This method enables the following syntax for String:

every(str) should fullymatch regex ("Hel*o world".r)
^

This method enables the following syntax for java.util.Map:

every(jmap) should fullymatch regex ("Hel*o world".r)
^

This method enables the following syntax for scala.collection.GenMap:

every(map) should fullymatch regex ("Hel*o world".r)
^

This method enables the following syntax:

every(xs) should fullymatch regex ("Hel*o world".r)
^

This method enables the following syntax for String:

exactly(str) should fullymatch regex ("Hel*o world".r)
^

This method enables the following syntax for java.util.Map:

exactly(jmap) should fullymatch regex ("Hel*o world".r)
^

This method enables the following syntax for scala.collection.GenMap:

exactly(map) should fullymatch regex ("Hel*o world".r)
^

This method enables the following syntax:

exactly(xs) should fullymatch regex ("Hel*o world".r)
^

Throws TestFailedException, with the passed Throwable cause, to indicate a test failed. The getMessage method of the thrown TestFailedException will return cause.toString.

Throws TestFailedException, with the passed String message as the exception's detail message and Throwable cause, to indicate a test failed.

Throws TestFailedException, with the passed String message as the exception's detail message, to indicate a test failed.

Throws TestFailedException to indicate a test failed.

This method enables the following syntax:

List(1, 2, 3) should contain (inOrder(1, 2))
                             ^

This method enables the following syntax:

List(1, 2, 3) should contain (inOrderElementsOf List(1, 2))
                             ^

This method enables the following syntax:

List(1, 2, 3) should contain (inOrderOnly(1, 2))
                             ^

Intercept and return an exception that's expected to be thrown by the passed function value. The thrown exception must be an instance of the type specified by the type parameter of this method. This method invokes the passed function. If the function throws an exception that's an instance of the specified type, this method returns that exception. Else, whether the passed function returns normally or completes abruptly with a different exception, this method throws TestFailedException.

Note that the type specified as this method's type parameter may represent any subtype of AnyRef, not just Throwable or one of its subclasses. In Scala, exceptions can be caught based on traits they implement, so it may at times make sense to specify a trait that the intercepted exception's class must mix in. If a class instance is passed for a type that could not possibly be used to catch an exception (such as String, for example), this method will complete abruptly with a TestFailedException.

Also note that the difference between this method and assertThrows is that this method returns the expected exception, so it lets you perform further assertions on that exception. By contrast, the assertThrows method returns Succeeded, which means it can serve as the last statement in an async- or safe-style suite. assertThrows also indicates to the reader of the code that nothing further is expected about the thrown exception other than its type. The recommended usage is to use assertThrows by default, intercept only when you need to inspect the caught exception further.

Provides an A CanEqual B for any two types A and B, enforcing the type constraint that A must be a subtype of B, given an implicit Equivalence[B].

The returned Constraint's areEqual method uses the implicitly passed Equivalence[A]'s areEquivalent method to determine equality.

This method is overridden and made implicit by subtraits LowPriorityTypeCheckedConstraint (extended by TypeCheckedTripleEquals), and overriden as non-implicit by the other subtraits in this package.

This method enables the following syntax:

exception should not have message ("file not found")
                         ^

This method enables the following syntax for String:

no(str) should fullymatch regex ("Hel*o world".r)
^

This method enables the following syntax for java.util.Map:

no(jmap) should fullymatch regex ("Hel*o world".r)
^

This method enables the following syntax:

no(xs) should fullymatch regex ("Hel*o world".r)
^

This method enables the following syntax:

List(1, 2, 3) should contain (noElementsOf List(1, 2))
                             ^

This field enables the following syntax:

noException should be thrownBy
^

This method enables the following syntax:

List(1, 2, 3) should contain (noneOf(1, 2))
                             ^

This method enables syntax such as the following:

book should have (message ("A TALE OF TWO CITIES") (of [Book]), title ("A Tale of Two Cities"))
                                                   ^

This method enables the following syntax:

List(1, 2, 3) should contain (oneElementOf (List(1, 2)))
                             ^

This method enables the following syntax:

List(1, 2, 3) should contain (oneOf(1, 2))
                             ^

This method enables the following syntax:

List(1, 2, 3) should contain (only(1, 2))
                             ^

Throws TestPendingException to indicate a test is pending.

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

To support this style of testing, a test can be given a name that specifies one bit of behavior required by the system being tested. The test can also include some code that sends more information about the behavior to the reporter when the tests run. At the end of the test, it can call method pending, which will cause it to complete abruptly with TestPendingException. Because tests in ScalaTest can be designated as pending with TestPendingException, both the test name and any information sent to the reporter when running the test can appear in the report of a test run. (In other words, the code of a pending test is executed just like any other test.) However, because the test completes abruptly with TestPendingException, the test will be reported as pending, to indicate the actual test, and possibly the functionality it is intended to test, has not yet been implemented.

Note: This method always completes abruptly with a TestPendingException. Thus it always has a side effect. Methods with side effects are usually invoked with parentheses, as in pending(). This method is defined as a parameterless method, in flagrant contradiction to recommended Scala style, because it forms a kind of DSL for pending tests. It enables tests in suites such as FunSuite or FunSpec to be denoted by placing "(pending)" after the test name, as in:

test("that style rules are not laws") (pending)

Readers of the code see "pending" in parentheses, which looks like a little note attached to the test name to indicate it is pending. Whereas "(pending()) looks more like a method call, "(pending)" lets readers stay at a higher level, forgetting how it is implemented and just focusing on the intent of the programmer who wrote the code.

Execute the passed block of code, and if it completes abruptly, throw TestPendingException, else throw TestFailedException.

This method can be used to temporarily change a failing test into a pending test in such a way that it will automatically turn back into a failing test once the problem originally causing the test to fail has been fixed. At that point, you need only remove the pendingUntilFixed call. In other words, a pendingUntilFixed surrounding a block of code that isn't broken is treated as a test failure. The motivation for this behavior is to encourage people to remove pendingUntilFixed calls when there are no longer needed.

This method facilitates a style of testing in which tests are written before the code they test. Sometimes you may encounter a test failure that requires more functionality than you want to tackle without writing more tests. In this case you can mark the bit of test code causing the failure with pendingUntilFixed. You can then write more tests and functionality that eventually will get your production code to a point where the original test won't fail anymore. At this point the code block marked with pendingUntilFixed will no longer throw an exception (because the problem has been fixed). This will in turn cause pendingUntilFixed to throw TestFailedException with a detail message explaining you need to go back and remove the pendingUntilFixed call as the problem orginally causing your test code to fail has been fixed.

This method enables the following syntax:

the [FileNotFoundException] should be thrownBy { ... }
^

This method enables the following syntax:

List(1, 2, 3) should contain (theSameElementsAs(List(1, 2, 3)))
                             ^

This method enables the following syntax:

List(1, 2, 3) should contain (theSameElementsInOrderAs(List(1, 2)))
                             ^

This method enables the following syntax:

a [RuntimeException] should be thrownBy {...}
                              ^

Provides an A CanEqual B instance for any two types A and B, enforcing the type constraint that B must be a subtype of A, given an implicit Equivalence[A].

The returned Constraint's areEqual method uses the implicitly passed Equivalence[A]'s areEquivalent method to determine equality.

This method is overridden and made implicit by subtraits TypeCheckedTripleEquals) and overriden as non-implicit by the other subtraits in this package.

Executes the block of code passed as the second parameter, and, if it completes abruptly with a ModifiableMessage exception, prepends the "clue" string passed as the first parameter to the beginning of the detail message of that thrown exception, then rethrows it. If clue does not end in a white space character, one space will be added between it and the existing detail message (unless the detail message is not defined).

This method allows you to add more information about what went wrong that will be reported when a test fails. Here's an example:

withClue("(Employee's name was: " + employee.name + ")") {
 intercept[IllegalArgumentException] {
   employee.getTask(-1)
 }
}

If an invocation of intercept completed abruptly with an exception, the resulting message would be something like:

(Employee's name was Bob Jones) Expected IllegalArgumentException to be thrown, but no exception was thrown

The conversionCheckedConstraint method has been deprecated and will be removed in a future version of Scalactic. It is no longer needed now that the deprecation period of ConversionCheckedTripleEquals has expired. It will not be replaced.

Provides an A CanEqual B instance for any two types A and B, enforcing the type constraint that B is implicitly convertible to A, given an implicit Equivalence[A].

The returned Constraint's areEqual method uses the implicitly passed Equivalence[A]'s areEquivalent method to determine equality.

This method is overridden and made implicit by subtraits ConversionCheckedTripleEquals) and overriden as non-implicit by the other subtraits in this package.

The convertEquivalenceToAToBConversionConstraint method has been deprecated and will be removed in a future version of Scalactic. It is no longer needed now that the deprecation period of ConversionCheckedTripleEquals has expired. It will not be replaced.

Provides an A CanEqual B instance for any two types A and B, enforcing the type constraint that A is implicitly convertible to B, given an explicit Equivalence[B].

This method is used to enable the Explicitly DSL for ConversionCheckedTripleEquals by requiring an explicit Equivalance[B], but taking an implicit function that converts from A to B.

The returned Constraint's areEqual method uses the implicitly passed Equivalence[B]'s areEquivalent method to determine equality.

This method is overridden and made implicit by subtraits LowPriorityConversionCheckedConstraint (extended by ConversionCheckedTripleEquals), and overriden as non-implicit by the other subtraits in this package.

The convertEquivalenceToBToAConversionConstraint method has been deprecated and will be removed in a future version of Scalactic. It is no longer needed now that the deprecation period of ConversionCheckedTripleEquals has expired. It will not be replaced.

Provides an A CanEqual B instance for any two types A and B, enforcing the type constraint that B is implicitly convertible to A, given an explicit Equivalence[A].

This method is used to enable the Explicitly DSL for ConversionCheckedTripleEquals by requiring an explicit Equivalance[A], but taking an implicit function that converts from B to A. For example, under ConversionCheckedTripleEquals, this method (as an implicit method), would be used to compile this statement:

def closeEnoughTo1(num: Double): Boolean =
 (num === 1.0)(decided by forgivingEquality)

The returned Constraint's areEqual method uses the implicitly passed Equivalence[A]'s areEquivalent method to determine equality.

This method is overridden and made implicit by subtraits ConversionCheckedTripleEquals) and overriden as non-implicit by the other subtraits in this package.

The lowPriorityConversionCheckedConstraint method has been deprecated and will be removed in a future version of Scalactic. It is no longer needed now that the deprecation period of ConversionCheckedTripleEquals has expired. It will not be replaced.

Provides an A CanEqual B instance for any two types A and B, enforcing the type constraint that A is implicitly convertible to B, given an implicit Equivalence[B].

The returned Constraint's areEqual method uses the implicitly passed Equivalence[B]'s areEquivalent method to determine equality.

This method is overridden and made implicit by subtraits LowPriorityConversionCheckedConstraint (extended by ConversionCheckedTripleEquals), and overriden as non-implicit by the other subtraits in this package.

Trap and return any thrown exception that would normally cause a ScalaTest test to fail, or create and return a new RuntimeException indicating no exception is thrown.

This method is intended to be used in the Scala interpreter to eliminate large stack traces when trying out ScalaTest assertions and matcher expressions. It is not intended to be used in regular test code. If you want to ensure that a bit of code throws an expected exception, use intercept, not trap. Here's an example interpreter session without trap:

scala> import org.scalatest._
import org.scalatest._

scala> import Matchers._
import Matchers._

scala> val x = 12
a: Int = 12

scala> x shouldEqual 13
org.scalatest.exceptions.TestFailedException: 12 did not equal 13
  at org.scalatest.Assertions$class.newAssertionFailedException(Assertions.scala:449)
  at org.scalatest.Assertions$.newAssertionFailedException(Assertions.scala:1203)
  at org.scalatest.Assertions$AssertionsHelper.macroAssertTrue(Assertions.scala:417)
  at .<init>(<console>:15)
  at .<clinit>(<console>)
  at .<init>(<console>:7)
  at .<clinit>(<console>)
  at $print(<console>)
  at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
  at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
  at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
  at java.lang.reflect.Method.invoke(Method.java:597)
  at scala.tools.nsc.interpreter.IMain$ReadEvalPrint.call(IMain.scala:731)
  at scala.tools.nsc.interpreter.IMain$Request.loadAndRun(IMain.scala:980)
  at scala.tools.nsc.interpreter.IMain.loadAndRunReq$1(IMain.scala:570)
  at scala.tools.nsc.interpreter.IMain.interpret(IMain.scala:601)
  at scala.tools.nsc.interpreter.IMain.interpret(IMain.scala:565)
  at scala.tools.nsc.interpreter.ILoop.reallyInterpret$1(ILoop.scala:745)
  at scala.tools.nsc.interpreter.ILoop.interpretStartingWith(ILoop.scala:790)
  at scala.tools.nsc.interpreter.ILoop.command(ILoop.scala:702)
  at scala.tools.nsc.interpreter.ILoop.processLine$1(ILoop.scala:566)
  at scala.tools.nsc.interpreter.ILoop.innerLoop$1(ILoop.scala:573)
  at scala.tools.nsc.interpreter.ILoop.loop(ILoop.scala:576)
  at scala.tools.nsc.interpreter.ILoop$$anonfun$process$1.apply$mcZ$sp(ILoop.scala:867)
  at scala.tools.nsc.interpreter.ILoop$$anonfun$process$1.apply(ILoop.scala:822)
  at scala.tools.nsc.interpreter.ILoop$$anonfun$process$1.apply(ILoop.scala:822)
  at scala.tools.nsc.util.ScalaClassLoader$.savingContextLoader(ScalaClassLoader.scala:135)
  at scala.tools.nsc.interpreter.ILoop.process(ILoop.scala:822)
  at scala.tools.nsc.MainGenericRunner.runTarget$1(MainGenericRunner.scala:83)
  at scala.tools.nsc.MainGenericRunner.process(MainGenericRunner.scala:96)
  at scala.tools.nsc.MainGenericRunner$.main(MainGenericRunner.scala:105)
  at scala.tools.nsc.MainGenericRunner.main(MainGenericRunner.scala)

That's a pretty tall stack trace. Here's what it looks like when you use trap:

scala> trap { x shouldEqual 13 }
res1: Throwable = org.scalatest.exceptions.TestFailedException: 12 did not equal 13

Much less clutter. Bear in mind, however, that if no exception is thrown by the passed block of code, the trap method will create a new NormalResult (a subclass of Throwable made for this purpose only) and return that. If the result was the Unit value, it will simply say that no exception was thrown:

scala> trap { x shouldEqual 12 }
res2: Throwable = No exception was thrown.

If the passed block of code results in a value other than Unit, the NormalResult's toString will print the value:

scala> trap { "Dude!" }
res3: Throwable = No exception was thrown. Instead, result was: "Dude!"

Although you can access the result value from the NormalResult, its type is Any and therefore not very convenient to use. It is not intended that trap be used in test code. The sole intended use case for trap is decluttering Scala interpreter sessions by eliminating stack traces when executing assertion and matcher expressions.

This field enables the following syntax:

badBook should not be a ('goodRead)
                     ^

This field enables syntax such as the following:

result should equal ("hello") (after being lowerCased)
                              ^

This field enables the following syntax:

badBook should not be an (excellentRead)
                     ^

This field enables syntax such as the following:

obj should (be theSameInstanceAs (string) and be theSameInstanceAs (string))
           ^

This field enables the following syntax:

"val a: String = 1" shouldNot compile
                             ^

This field enables syntax such as the following:

list should (contain ('a') and have length (7))
            ^

This field enables syntax such as the following:

result should equal ("hello") (decided by defaultEquality)
                              ^

This field enables the following syntax:

seq should be (defined)
             ^

This field enables syntax such as the following, given an Equivalence[String] named myStringEquivalence:

result should equal ("hello") (determined by myStringEquivalence)
                              ^

This field enables the following syntax:

list should be (empty)
               ^

This field enables syntax such as the following:

string should (endWith ("ago") and include ("score"))
              ^

This field enables the following syntax:

file should exist
           ^

This field enables syntax such as the following:

string should (fullyMatch regex ("Hel*o, wor.d") and not have length (99))
              ^

This field enables syntax such as the following:

list should (have length (3) and not contain ('a'))
            ^

This field enables syntax such as the following:

string should (include ("hope") and not startWith ("no"))
              ^

This field enables the following syntax:

map should not contain key (10)
                      ^

This field enables the following syntax:

"hi" should not have length (3)
                    ^

This field enables the following syntax:

result should matchPattern { case Person("Bob", _) => }
             ^

This field enables syntax like the following:

myFile should (not be an (directory) and not have ('name ("foo.bar")))
              ^

This field enables the following syntax:

file should be (readable)
               ^

This field enables the following syntax:

"eight" should not fullyMatch regex ("""(-)?(\d+)(\.\d*)?""".r)
                             ^

This field enables the following syntax:

set should not have size (3)
                   ^

This field enables the following syntax:

seq should be (sorted)
             ^

This field enables syntax such as the following:

string should (startWith ("Four") and include ("year"))
              ^

The Succeeded singleton.

You can use succeed to solve a type error when an async test does not end in either Future[Assertion] or Assertion. Because Assertion is a type alias for Succeeded.type, putting succeed at the end of a test body (or at the end of a function being used to map the final future of a test body) will solve the type error.

This field enables the following syntax:

oneString should not be theSameInstanceAs (anotherString)
                       ^

This field enables the following syntax:

"val a: String = 1" shouldNot typeCheck
                             ^

This field enables the following syntax:

map should not contain value (10)
                      ^

This field enables the following syntax:

file should be (writable)
               ^