AsyncTestSuite
The base trait of ScalaTest's asynchronous testing styles, which defines a
withFixture
lifecycle method that accepts as its parameter a test function
that returns a FutureOutcome
.
The withFixture
method add by this trait has the
following signature and implementation:
def withFixture(test: NoArgAsyncTest): FutureOutcome = { test() }
This trait enables testing of asynchronous code without blocking. Instead of returning
Outcome
like TestSuite
's
withFixture
, this trait's withFixture
method returns a
FutureOutcome
. Similarly, the apply
method of test function interface,
NoArgAsyncTest
, returns FutureOutcome
:
// In trait NoArgAsyncTest: def apply(): FutureOutcome
The withFixture
method supports async testing, because when the test function returns,
the test body has not necessarily finished execution.
The recommended way to ensure cleanup is performed after a test body finishes execution is
to use a complete
-lastly
clause, syntax that is defined in trait
CompleteLastly
, which this trait extends.
Using cleanup
-lastly
will ensure that cleanup will occur whether
FutureOutcome
-producing code completes abruptly by throwing an exception, or returns
normally yielding a FutureOutcome
. In the latter case,
complete
-lastly
will
register the cleanup code to execute asynchronously when the FutureOutcome
completes.
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)
”. Thus, the recommended
structure of a withFixture
implementation that performs cleanup looks like this:
// Your implementation override def withFixture(test: NoArgAsyncTest) = { // Perform setup here complete { super.withFixture(test) // Invoke the test function } lastly { // Perform cleanup here } }
If you have no cleanup to perform, you can write withFixture
like this instead:
// Your implementation override def withFixture(test: NoArgAsyncTest) = { // Perform setup here super.withFixture(test) // Invoke the test function }
The test function and withFixture
method returns a
FutureOutcome
,
a ScalaTest class that wraps a Scala Future[Outcome]
and offers methods
more specific to asynchronous test outcomes. In a Scala Future
, any exception
results in a scala.util.Failure
. In a FutureOutcome
, a
thrown TestPendingException
always results in a Pending
,
a thrown TestCanceledException
always results in a Canceled
,
and any other exception, so long as it isn't suite-aborting, results in a
Failed
. This is true of the asynchronous test code itself that's represented by
the FutureOutcome
and any transformation or callback registered on the
FutureOutcome
in withFixture
.
If you want to perform an action only for certain outcomes, you'll need to
register code performing that action on the FutureOutcome
using
one of FutureOutcome
's callback registration methods:
-
onSucceededThen
- executed if theOutcome
is aSucceeded
. -
onFailedThen
- executed if theOutcome
is aFailed
. -
onCanceledThen
- executed if theOutcome
is aCanceled
. -
onPendingThen
- executed if theOutcome
is aPending
. -
onOutcomeThen
- executed on anyOutcome
(i.e., no suite-aborting exception is thrown). -
onAbortedThen
- executed if a suite-aborting exception is thrown. -
onCompletedThen
- executed whether the result is anOutcome
or a thrown suite-aborting exception.
For example, if you want to perform an action if a test fails, you'd register the
callback using onFailedThen
, like this:
// Your implementation override def withFixture(test: NoArgAsyncTest) = { // Perform setup here val futureOutcome = super.withFixture(test) // Invoke the test function futureOutcome onFailedThen { ex => // perform action that you want to occur // only if a test fails here } }
Note that all callback registration methods, such as onFailedThen
used in the
previous example, return a new FutureOutcome
that won't complete until the
the original FutureOutcome
and the callback has completed. If the callback
throws an exception, the resulting FutureOutcome
will represent that exception.
For example, if a FutureOutcome
results in Failed
, but a callback
registered on that FutureOutcome
with onFailedThen
throws TestPendingException
, the
result of the FutureOutcome
returned by onFailedThen
will
be Pending
.
Lastly, if you want to change the outcome in some way in withFixture
, you'll need to use
the change
method of FutureOutcome
, like this:
// Your implementation override def withFixture(test: NoArgAsyncTest) = { // Perform setup here val futureOutcome = super.withFixture(test) // Invoke the test function futureOutcome change { outcome => // transform the outcome into a new outcome here } }
Type members
Classlikes
A test function taking no arguments and returning a FutureOutcome
.
A test function taking no arguments and returning a FutureOutcome
.
For more detail and examples, see the relevant section in the
documentation for trait AsyncFlatSpec
.
Inherited classlikes
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:
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))
- Value parameters:
- leftSide
An object to convert to
Equalizer
, which represents the value on the left side of a===
or!==
invocation.
- Inherited from:
- TripleEqualsSupport
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:
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))
- Value parameters:
- leftSide
An object to convert to
Equalizer
, which represents the value on the left side of a===
or!==
invocation.
- Inherited from:
- TripleEqualsSupport
Class that provides the lastly
method of the complete
-lastly
syntax.
Class that provides the lastly
method of the complete
-lastly
syntax.
- Value parameters:
- futuristic
the futuristic typeclass instance
- futuristicBlock
a by-name that produces a futuristic type
- Inherited from:
- CompleteLastly
Value members
Concrete methods
Run an async test.
Run an async test.
This method is redefine in this trait solely to narrow its contract. Subclasses must implement
this method to call the withFixture(NoArgAsyncTest)
method, which is defined in
this trait.
This trait's implementation of this method simply returns SucceededStatus
and has no other effect.
- Value parameters:
- args
the
Args
for this run- testName
the name of one async test to execute.
- Returns:
a
Status
object that indicates when the test started by this method has completed, and whether or not it failed.- Throws:
- NullArgumentException
if either
testName
orargs
isnull
.
- Definition Classes
Run the passed test function in the context of a fixture established by this method.
Run the passed test function in the context of a fixture established by this method.
This method should set up the fixture needed by the tests of the
current suite, invoke the test function, and if needed, register a callback
on the resulting FutureOutcome
to perform any clean
up needed after the test completes. Because the NoArgAsyncTest
function
passed to this method takes no parameters, preparing the fixture will require
side effects, such as reassigning instance var
s in this Suite
or initializing
a globally accessible external database. If you want to avoid reassigning instance var
s
you can use FixtureAsyncTestSuite.
This trait's implementation of runTest
invokes this method for each test, passing
in a NoArgAsyncTest
whose apply
method will execute the code of the test
and returns its result.
This trait's implementation of this method simply invokes the passed NoArgAsyncTest
function.
- Value parameters:
- test
the no-arg async test function to run with a fixture
Inherited methods
Returns a TripleEqualsInvocationOnSpread[T]
, given an Spread[T]
, to facilitate
the “<left> should !== (<pivot> +- <tolerance>)
”
syntax of Matchers
.
Returns a TripleEqualsInvocationOnSpread[T]
, given an Spread[T]
, to facilitate
the “<left> should !== (<pivot> +- <tolerance>)
”
syntax of Matchers
.
- Value parameters:
- right
the
Spread[T]
against which to compare the left-hand value
- Returns:
a
TripleEqualsInvocationOnSpread
wrapping the passedSpread[T]
value, withexpectingEqual
set tofalse
.- Inherited from:
- TripleEqualsSupport
Returns a TripleEqualsInvocation[Null]
, given a null
reference, to facilitate
the “<left> should !== null
” syntax
of Matchers
.
Returns a TripleEqualsInvocation[Null]
, given a null
reference, to facilitate
the “<left> should !== null
” syntax
of Matchers
.
- Value parameters:
- right
a null reference
- Returns:
a
TripleEqualsInvocation
wrapping the passednull
value, withexpectingEqual
set tofalse
.- Inherited from:
- TripleEqualsSupport
Returns a TripleEqualsInvocation[T]
, given an object of type T
, to facilitate
the “<left> should !== <right>
” syntax
of Matchers
.
Returns a TripleEqualsInvocation[T]
, given an object of type T
, to facilitate
the “<left> should !== <right>
” syntax
of Matchers
.
- Value parameters:
- right
the right-hand side value for an equality assertion
- Returns:
a
TripleEqualsInvocation
wrapping the passed right value, withexpectingEqual
set tofalse
.- Inherited from:
- TripleEqualsSupport
Returns a TripleEqualsInvocationOnSpread[T]
, given an Spread[T]
, to facilitate
the “<left> should === (<pivot> +- <tolerance>)
”
syntax of Matchers
.
Returns a TripleEqualsInvocationOnSpread[T]
, given an Spread[T]
, to facilitate
the “<left> should === (<pivot> +- <tolerance>)
”
syntax of Matchers
.
- Value parameters:
- right
the
Spread[T]
against which to compare the left-hand value
- Returns:
a
TripleEqualsInvocationOnSpread
wrapping the passedSpread[T]
value, withexpectingEqual
set totrue
.- Inherited from:
- TripleEqualsSupport
Returns a TripleEqualsInvocation[Null]
, given a null
reference, to facilitate
the “<left> should === null
” syntax
of Matchers
.
Returns a TripleEqualsInvocation[Null]
, given a null
reference, to facilitate
the “<left> should === null
” syntax
of Matchers
.
- Value parameters:
- right
a null reference
- Returns:
a
TripleEqualsInvocation
wrapping the passednull
value, withexpectingEqual
set totrue
.- Inherited from:
- TripleEqualsSupport
Returns a TripleEqualsInvocation[T]
, given an object of type T
, to facilitate
the “<left> should === <right>
” syntax
of Matchers
.
Returns a TripleEqualsInvocation[T]
, given an object of type T
, to facilitate
the “<left> should === <right>
” syntax
of Matchers
.
- Value parameters:
- right
the right-hand side value for an equality assertion
- Returns:
a
TripleEqualsInvocation
wrapping the passed right value, withexpectingEqual
set totrue
.- Inherited from:
- TripleEqualsSupport
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.
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.
- Value parameters:
- clue
An objects whose
toString
method returns a message to include in a failure report.- condition
the boolean condition to assert
- Throws:
- NullArgumentException
if
message
isnull
.- TestFailedException
if the condition is
false
.
- Inherited from:
- Assertions
Assert that a boolean condition is true.
If the condition is true
, this method returns normally.
Else, it throws TestFailedException
.
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.
- Value parameters:
- condition
the boolean condition to assert
- Throws:
- TestFailedException
if the condition is
false
.
- Inherited from:
- Assertions
Asserts that a given string snippet of code passes both the Scala parser and type checker.
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.
- Value parameters:
- code
the snippet of code that should compile
- Inherited from:
- Assertions
Asserts that a given string snippet of code does not pass either the Scala parser or type checker.
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
.
- Value parameters:
- code
the snippet of code that should not type check
- Inherited from:
- Assertions
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
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.
- Value parameters:
- actual
the actual value, which should equal the passed
expected
value- expected
the expected value
- Throws:
- TestFailedException
if the passed
actual
value does not equal the passedexpected
value.
- Inherited from:
- Assertions
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
.
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
.
- Value parameters:
- actual
the actual value, which should equal the passed
expected
value- clue
An object whose
toString
method returns a message to include in a failure report.- expected
the expected value
- Throws:
- TestFailedException
if the passed
actual
value does not equal the passedexpected
value.
- Inherited from:
- Assertions
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
.
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.
- Value parameters:
- classTag
an implicit
ClassTag
representing the type of the specified type parameter.- f
the function value that should throw the expected exception
- Returns:
the
Succeeded
singleton, if an exception of the expected type is thrown- Throws:
- TestFailedException
if the passed function does not complete abruptly with an exception that's an instance of the specified type.
- Inherited from:
- Assertions
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.
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
.
- Value parameters:
- code
the snippet of code that should not type check
- Inherited from:
- Assertions
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.
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.
- Value parameters:
- clue
An objects whose
toString
method returns a message to include in a failure report.- condition
the boolean condition to assume
- Throws:
- NullArgumentException
if
message
isnull
.- TestCanceledException
if the condition is
false
.
- Inherited from:
- Assertions
Assume that a boolean condition is true.
If the condition is true
, this method returns normally.
Else, it throws TestCanceledException
.
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.
- Value parameters:
- condition
the boolean condition to assume
- Throws:
- TestCanceledException
if the condition is
false
.
- Inherited from:
- Assertions
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
Throwable
cause, to indicate a test failed.
The getMessage
method of the thrown TestCanceledException
will return cause.toString
.
- Value parameters:
- cause
a
Throwable
that indicates the cause of the cancellation.
- Throws:
- NullArgumentException
if
cause
isnull
- Inherited from:
- Assertions
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 and Throwable
cause, to indicate a test failed.
- Value parameters:
- cause
A
Throwable
that indicates the cause of the failure.- message
A message describing the failure.
- Throws:
- NullArgumentException
if
message
orcause
isnull
- Inherited from:
- Assertions
Throws TestCanceledException
, with the passed
String
message
as the exception's detail
message, to indicate a test was canceled.
Throws TestCanceledException
, with the passed
String
message
as the exception's detail
message, to indicate a test was canceled.
- Value parameters:
- message
A message describing the cancellation.
- Throws:
- NullArgumentException
if
message
isnull
- Inherited from:
- Assertions
Throws TestCanceledException
to indicate a test was canceled.
Throws TestCanceledException
to indicate a test was canceled.
- Inherited from:
- Assertions
Registers a block of code that produces any "futuristic" type (any type F
for which
an implicit Futuristic[F]
instance is implicitly available), returning
an object that offers a lastly
method.
Registers a block of code that produces any "futuristic" type (any type F
for which
an implicit Futuristic[F]
instance is implicitly available), returning
an object that offers a lastly
method.
See the main documentation for trait CompleteLastly
for more detail.
- Value parameters:
- completeBlock
cleanup code to execute whether the code passed to
complete
throws an exception or succesfully returns a futuristic value.
- Inherited from:
- CompleteLastly
- Definition Classes
- TripleEquals -> TripleEqualsSupport
- Inherited from:
- TripleEquals
- Definition Classes
- TripleEquals -> TripleEqualsSupport
- Inherited from:
- TripleEquals
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 ==
.
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 ==
.
- Returns:
a default
Equality
for typeA
- Inherited from:
- TripleEqualsSupport
Executes one or more tests in this Suite
, printing results to the standard output.
Executes one or more tests in this Suite
, printing results to the standard output.
This method invokes run
on itself, passing in values that can be configured via the parameters to this
method, all of which have default values. This behavior is convenient when working with ScalaTest in the Scala interpreter.
Here's a summary of this method's parameters and how you can use them:
The testName
parameter
If you leave testName
at its default value (of null
), this method will pass None
to
the testName
parameter of run
, and as a result all the tests in this suite will be executed. If you
specify a testName
, this method will pass Some(testName)
to run
, and only that test
will be run. Thus to run all tests in a suite from the Scala interpreter, you can write:
scala> (new ExampleSuite).execute()
(The above syntax actually invokes the overloaded parameterless form of execute
, which calls this form with its default parameter values.)
To run just the test named "my favorite test"
in a suite from the Scala interpreter, you would write:
scala> (new ExampleSuite).execute("my favorite test")
Or:
scala> (new ExampleSuite).execute(testName = "my favorite test")
The configMap
parameter
If you provide a value for the configMap
parameter, this method will pass it to run
. If not, the default value
of an empty Map
will be passed. For more information on how to use a config map to configure your test suites, see
the config map section in the main documentation for this trait. Here's an example in which you configure
a run with the name of an input file:
scala> (new ExampleSuite).execute(configMap = Map("inputFileName" -> "in.txt")
The color
parameter
If you leave the color
parameter unspecified, this method will configure the reporter it passes to run
to print
to the standard output in color (via ansi escape characters). If you don't want color output, specify false for color
, like this:
scala> (new ExampleSuite).execute(color = false)
The durations
parameter
If you leave the durations
parameter unspecified, this method will configure the reporter it passes to run
to
not print durations for tests and suites to the standard output. If you want durations printed, specify true for durations
,
like this:
scala> (new ExampleSuite).execute(durations = true)
The shortstacks
and fullstacks
parameters
If you leave both the shortstacks
and fullstacks
parameters unspecified, this method will configure the reporter
it passes to run
to not print stack traces for failed tests if it has a stack depth that identifies the offending
line of test code. If you prefer a short stack trace (10 to 15 stack frames) to be printed with any test failure, specify true for
shortstacks
:
scala> (new ExampleSuite).execute(shortstacks = true)
For full stack traces, set fullstacks
to true:
scala> (new ExampleSuite).execute(fullstacks = true)
If you specify true for both shortstacks
and fullstacks
, you'll get full stack traces.
The stats
parameter
If you leave the stats
parameter unspecified, this method will not fire RunStarting
and either RunCompleted
or RunAborted
events to the reporter it passes to run
.
If you specify true for stats
, this method will fire the run events to the reporter, and the reporter will print the
expected test count before the run, and various statistics after, including the number of suites completed and number of tests that
succeeded, failed, were ignored or marked pending. Here's how you get the stats:
scala> (new ExampleSuite).execute(stats = true)
To summarize, this method will pass to run
:
-
testName
-None
if this method'stestName
parameter is left at its default value ofnull
, elseSome(testName)
. -
reporter
- a reporter that prints to the standard output -
stopper
- aStopper
whoseapply
method always returnsfalse
-
filter
- aFilter
constructed withNone
fortagsToInclude
andSet()
fortagsToExclude
-
configMap
- theconfigMap
passed to this method -
distributor
-None
-
tracker
- a newTracker
Note: In ScalaTest, the terms "execute" and "run" basically mean the same thing and
can be used interchangably. The reason this method isn't named run
is that it takes advantage of
default arguments, and you can't mix overloaded methods and default arguments in Scala. (If named run
,
this method would have the same name but different arguments than the main run
method that
takes seven arguments. Thus it would overload and couldn't be used with default argument values.)
Design note: This method has two "features" that may seem unidiomatic. First, the default value of testName
is null
.
Normally in Scala the type of testName
would be Option[String]
and the default value would
be None
, as it is in this trait's run
method. The null
value is used here for two reasons. First, in
ScalaTest 1.5, execute
was changed from four overloaded methods to one method with default values, taking advantage of
the default and named parameters feature introduced in Scala 2.8.
To not break existing source code, testName
needed to have type String
, as it did in two of the overloaded
execute
methods prior to 1.5. The other reason is that execute
has always been designed to be called primarily
from an interpeter environment, such as the Scala REPL (Read-Evaluate-Print-Loop). In an interpreter environment, minimizing keystrokes is king.
A String
type with a null
default value lets users type suite.execute("my test name")
rather than
suite.execute(Some("my test name"))
, saving several keystrokes.
The second non-idiomatic feature is that shortstacks
and fullstacks
are all lower case rather than
camel case. This is done to be consistent with the Shell
, which also uses those forms. The reason
lower case is used in the Shell
is to save keystrokes in an interpreter environment. Most Unix commands, for
example, are all lower case, making them easier and quicker to type. In the ScalaTest
Shell
, methods like shortstacks
, fullstacks
, and nostats
, etc., are
designed to be all lower case so they feel more like shell commands than methods.
- Value parameters:
- color
a boolean that configures whether output is printed in color
- configMap
a
Map
of key-value pairs that can be used by the executingSuite
of tests.- durations
a boolean that configures whether test and suite durations are printed to the standard output
- fullstacks
a boolean that configures whether full stack traces should be printed for test failures
- shortstacks
a boolean that configures whether short stack traces should be printed for test failures
- stats
a boolean that configures whether test and suite statistics are printed to the standard output
- testName
the name of one test to run.
- Throws:
- IllegalArgumentException
if
testName
is defined, but no test with the specified test name exists in thisSuite
- NullArgumentException
if the passed
configMap
parameter isnull
.
- Inherited from:
- Suite
The total number of tests that are expected to run when this Suite
's run
method is invoked.
The total number of tests that are expected to run when this Suite
's run
method is invoked.
This trait's implementation of this method returns the sum of:
-
the size of the
testNames
List
, minus the number of tests marked as ignored and any tests that are exluded by the passedFilter
-
the sum of the values obtained by invoking
expectedTestCount
on every nestedSuite
contained innestedSuites
- Value parameters:
- filter
a
Filter
with which to filter tests to count based on their tags
- Inherited from:
- Suite
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
Throwable
cause, to indicate a test failed.
The getMessage
method of the thrown TestFailedException
will return cause.toString
.
- Value parameters:
- cause
a
Throwable
that indicates the cause of the failure.
- Throws:
- NullArgumentException
if
cause
isnull
- Inherited from:
- Assertions
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 and Throwable
cause, to indicate a test failed.
- Value parameters:
- cause
A
Throwable
that indicates the cause of the failure.- message
A message describing the failure.
- Throws:
- NullArgumentException
if
message
orcause
isnull
- Inherited from:
- Assertions
Throws TestFailedException
, with the passed
String
message
as the exception's detail
message, to indicate a test failed.
Throws TestFailedException
, with the passed
String
message
as the exception's detail
message, to indicate a test failed.
- Value parameters:
- message
A message describing the failure.
- Throws:
- NullArgumentException
if
message
isnull
- Inherited from:
- Assertions
Throws TestFailedException
to indicate a test failed.
Throws TestFailedException
to indicate a test failed.
- Inherited from:
- Assertions
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
.
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.
- Value parameters:
- classTag
an implicit
ClassTag
representing the type of the specified type parameter.- f
the function value that should throw the expected exception
- Returns:
the intercepted exception, if it is of the expected type
- Throws:
- TestFailedException
if the passed function does not complete abruptly with an exception that's an instance of the specified type.
- Inherited from:
- Assertions
- Definition Classes
- TripleEquals -> TripleEqualsSupport
- Inherited from:
- TripleEquals
An immutable IndexedSeq
of this Suite
object's nested Suite
s. If this Suite
contains no nested Suite
s,
this method returns an empty IndexedSeq
. This trait's implementation of this method returns an empty List
.
An immutable IndexedSeq
of this Suite
object's nested Suite
s. If this Suite
contains no nested Suite
s,
this method returns an empty IndexedSeq
. This trait's implementation of this method returns an empty List
.
- Inherited from:
- Suite
Throws TestPendingException
to indicate a test is pending.
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.
- Inherited from:
- Assertions
Execute the passed block of code, and if it completes abruptly, throw TestPendingException
, else
throw TestFailedException
.
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.
- Value parameters:
- f
a block of code, which if it completes abruptly, should trigger a
TestPendingException
- Throws:
- TestPendingException
if the passed block of code completes abruptly with an
Exception
orAssertionError
- Inherited from:
- Assertions
Transforms a future of any type into a Future[T]
, where T
is a given
expected exception type, which succeeds if the given future
completes with a Failure
containing the specified exception type.
Transforms a future of any type into a Future[T]
, where T
is a given
expected exception type, which succeeds if the given future
completes with a Failure
containing the specified exception type.
See the main documentation for this trait for more detail and examples.
- Value parameters:
- future
A future of any type, which you expect to fail with an exception of the specified type T
- Returns:
a Future[T] containing on success the expected exception, or containing on failure a
TestFailedException
- Inherited from:
- RecoverMethods
Transforms a future of any type into a Future[Assertion]
that succeeds if the future
completes with a Failure
containing the specified exception type.
Transforms a future of any type into a Future[Assertion]
that succeeds if the future
completes with a Failure
containing the specified exception type.
See the main documentation for this trait for more detail and examples.
- Value parameters:
- future
A future of any type, which you expect to fail with an exception of the specified type T
- Returns:
a Future[Assertion] containing on success the
Succeeded
singleton, or containing on failure aTestFailedException
- Inherited from:
- RecoverMethods
The fully qualified class name of the rerunner to rerun this suite. This implementation will look at this.getClass and see if it is either an accessible Suite, or it has a WrapWith annotation. If so, it returns the fully qualified class name wrapped in a Some, or else it returns None.
The fully qualified class name of the rerunner to rerun this suite. This implementation will look at this.getClass and see if it is either an accessible Suite, or it has a WrapWith annotation. If so, it returns the fully qualified class name wrapped in a Some, or else it returns None.
- Inherited from:
- Suite
Runs this suite of tests.
Runs this suite of tests.
If testName
is None
, this trait's implementation of this method
calls these two methods on this object in this order:
-
runNestedSuites
-
runTests
If testName
is defined, then this trait's implementation of this method
calls runTests
, but does not call runNestedSuites
. This behavior
is part of the contract of this method. Subclasses that override run
must take
care not to call runNestedSuites
if testName
is defined. (The
OneInstancePerTest
trait depends on this behavior, for example.)
Subclasses and subtraits that override this run
method can implement them without
invoking either the runTests
or runNestedSuites
methods, which
are invoked by this trait's implementation of this method. It is recommended, but not required,
that subclasses and subtraits that override run
in a way that does not
invoke runNestedSuites
also override runNestedSuites
and make it
final. Similarly it is recommended, but not required,
that subclasses and subtraits that override run
in a way that does not
invoke runTests
also override runTests
(and runTest
,
which this trait's implementation of runTests
calls) and make it
final. The implementation of these final methods can either invoke the superclass implementation
of the method, or throw an UnsupportedOperationException
if appropriate. The
reason for this recommendation is that ScalaTest includes several traits that override
these methods to allow behavior to be mixed into a Suite
. For example, trait
BeforeAndAfterEach
overrides runTests
s. In a Suite
subclass that no longer invokes runTests
from run
, the
BeforeAndAfterEach
trait is not applicable. Mixing it in would have no effect.
By making runTests
final in such a Suite
subtrait, you make
the attempt to mix BeforeAndAfterEach
into a subclass of your subtrait
a compiler error. (It would fail to compile with a complaint that BeforeAndAfterEach
is trying to override runTests
, which is a final method in your trait.)
- Value parameters:
- args
the
Args
for this run- testName
an optional name of one test to run. If
None
, all relevant tests should be run. I.e.,None
acts like a wildcard that means run all relevant tests in thisSuite
.
- Returns:
a
Status
object that indicates when all tests and nested suites started by this method have completed, and whether or not a failure occurred.- Throws:
- IllegalArgumentException
if
testName
is defined, but no test with the specified test name exists in thisSuite
- NullArgumentException
if any passed parameter is
null
.
- Inherited from:
- Suite
A string ID for this Suite
that is intended to be unique among all suites reported during a run.
A string ID for this Suite
that is intended to be unique among all suites reported during a run.
This trait's
implementation of this method returns the fully qualified name of this object's class.
Each suite reported during a run will commonly be an instance of a different Suite
class,
and in such cases, this default implementation of this method will suffice. However, in special cases
you may need to override this method to ensure it is unique for each reported suite. For example, if you write
a Suite
subclass that reads in a file whose name is passed to its constructor and dynamically
creates a suite of tests based on the information in that file, you will likely need to override this method
in your Suite
subclass, perhaps by appending the pathname of the file to the fully qualified class name.
That way if you run a suite of tests based on a directory full of these files, you'll have unique suite IDs for
each reported suite.
The suite ID is intended to be unique, because ScalaTest does not enforce that it is unique. If it is not unique, then you may not be able to uniquely identify a particular test of a particular suite. This ability is used, for example, to dynamically tag tests as having failed in the previous run when rerunning only failed tests.
- Returns:
this
Suite
object's ID.- Inherited from:
- Suite
A user-friendly suite name for this Suite
.
A user-friendly suite name for this Suite
.
This trait's
implementation of this method returns the simple name of this object's class. This
trait's implementation of runNestedSuites
calls this method to obtain a
name for Report
s to pass to the suiteStarting
, suiteCompleted
,
and suiteAborted
methods of the Reporter
.
- Returns:
this
Suite
object's suite name.- Inherited from:
- Suite
A Map
whose keys are String
names of tests that are tagged and
whose associated values are the Set
of tag names for the test. If a test has no associated tags, its name
does not appear as a key in the returned Map
. If this Suite
contains no tests with tags, this
method returns an empty Map
.
A Map
whose keys are String
names of tests that are tagged and
whose associated values are the Set
of tag names for the test. If a test has no associated tags, its name
does not appear as a key in the returned Map
. If this Suite
contains no tests with tags, this
method returns an empty Map
.
This trait's implementation of this method uses Java reflection to discover any Java annotations attached to its test methods. The
fully qualified name of each unique annotation that extends TagAnnotation
is considered a tag. This trait's
implementation of this method, therefore, places one key/value pair into to the
Map
for each test for which a tag annotation is discovered through reflection.
In addition to test methods annotations, this trait's implementation will also auto-tag test methods 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.
Subclasses may override this method to define and/or discover tags in a custom manner, but overriding method implementations
should never return an empty Set
as a value. If a test has no tags, its name should not appear as a key in the
returned Map
.
- Inherited from:
- Suite
Provides a TestData
instance for the passed test name, given the passed config map.
Provides a TestData
instance for the passed test name, given the passed config map.
This method is used to obtain a TestData
instance to pass to withFixture(NoArgTest)
and withFixture(OneArgTest)
and the beforeEach
and afterEach
methods
of trait BeforeAndAfterEach
.
- Value parameters:
- testName
the name of the test for which to return a
TestData
instance- theConfigMap
the config map to include in the returned
TestData
- Returns:
a
TestData
instance for the specified test, which includes the specified config map- Inherited from:
- Suite
A Set
of test names. If this Suite
contains no tests, this method returns an empty Set
.
A Set
of test names. If this Suite
contains no tests, this method returns an empty Set
.
This trait's implementation of this method returns an empty Set
.
- Inherited from:
- Suite
- Definition Classes
- TripleEquals -> TripleEqualsSupport
- Inherited from:
- TripleEquals
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).
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
- Throws:
- NullArgumentException
if the passed
clue
isnull
- Inherited from:
- Assertions
Deprecated and Inherited methods
- Deprecated
- Definition Classes
- TripleEquals -> TripleEqualsSupport
- Inherited from:
- TripleEquals
- Deprecated
- Definition Classes
- TripleEquals -> TripleEqualsSupport
- Inherited from:
- TripleEquals
- Deprecated
- Definition Classes
- TripleEquals -> TripleEqualsSupport
- Inherited from:
- TripleEquals
- Deprecated
- Definition Classes
- TripleEquals -> TripleEqualsSupport
- Inherited from:
- TripleEquals
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.
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.
- Deprecated
- Inherited from:
- Assertions
Inherited fields
The Succeeded
singleton.
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.
- Inherited from:
- Assertions
Deprecated and Inherited fields
The styleName
lifecycle method has been deprecated and will be removed in a future version of ScalaTest.
The styleName
lifecycle method has been deprecated and will be removed in a future version of ScalaTest.
This method was used to support the chosen styles feature, which was deactivated in 3.1.0. The internal modularization of ScalaTest in 3.2.0
will replace chosen styles as the tool to encourage consistency across a project. We do not plan a replacement for styleName
.
- Deprecated
- Inherited from:
- Suite
Extensions
Inherited extensions
Implicits
Implicits
Implicitly converts an Assertion
to a Future[Assertion]
.
Implicitly converts an Assertion
to a Future[Assertion]
.
This implicit conversion is used to allow synchronous tests to be included along with
asynchronous tests in an AsyncTestSuite
. It will be
- Value parameters:
- assertion
the
Assertion
to convert
- Returns:
a
Future[Assertion]
that has already completed successfully (containing theSucceeded
singleton).
Inherited implicits
- Definition Classes
- TripleEquals -> TripleEqualsSupport
- Inherited from:
- TripleEquals