Trait extended by matcher objects, which may appear after the word be
, that can match against a Boolean
property. The match will succeed if and only if the Boolean
property equals true
.
The object containing the property, which must be of the type specified by the BePropertyMatcher
's type
parameter T
, is passed to the BePropertyMatcher
's
apply
method. The result is a BePropertyMatchResult
.
A BePropertyMatcher
is, therefore, a function from the specified type, T
, to
a BePropertyMatchResult
.
Although BePropertyMatcher
and Matcher
represent similar concepts, they have no inheritance relationship
because Matcher
is intended for use right after should
or must
whereas BePropertyMatcher
is intended for use right after be
.
A BePropertyMatcher
essentially allows you to write statically typed Boolean
property assertions similar to the dynamic ones that use symbols:
tempFile should be a ('file) // dynamic: uses reflection tempFile should be a (file) // type safe: only works on Files; no reflection used
One good way to organize custom matchers is to place them inside one or more traits that
you can then mix into the suites or specs that need them. Here's an example that
includes two BePropertyMatcher
s:
trait CustomMatchers {class FileBePropertyMatcher extends BePropertyMatcher[java.io.File] { def apply(left: java.io.File) = BePropertyMatchResult(left.isFile, "file") }
class DirectoryBePropertyMatcher extends BePropertyMatcher[java.io.File] { def apply(left: java.io.File) = BePropertyMatchResult(left.isDirectory, "directory") }
val file = new FileBePropertyMatcher val directory = new DirectoryBePropertyMatcher }
Because the type parameter of these two BePropertyMatcher
s is java.io.File
, they
can only be used with instances of that type. (The compiler will enforce this.) All they do is create a
BePropertyMatchResult
whose matches
field is true
if and only if the Boolean
property
is true
. The second field, propertyName
, is simply the string name of the property.
The file
and directory
val
s create variables that can be used in
matcher expressions that test whether a java.io.File
is a file or a directory. Here's an example:
class ExampleSpec extends Spec with ShouldMatchers with CustomMatchers {describe("A temp file") {
it("should be a file, not a directory") {
val tempFile = java.io.File.createTempFile("delete", "me")
try { tempFile should be a (file) tempFile should not be a (directory) } finally { tempFile.delete() } } } }
These matches should succeed, but if for example the first match, tempFile should be a (file)
, were to fail, you would get an error message like:
/tmp/delme1234me was not a file
For more information on BePropertyMatchResult
and the meaning of its fields, please
see the documentation for BePropertyMatchResult
. To understand why BePropertyMatcher
is contravariant in its type parameter, see the section entitled "Matcher's variance" in the
documentation for Matcher
.
o != arg0
is the same as !(o == (arg0))
.
o != arg0
is the same as !(o == (arg0))
.
the object to compare against this object for dis-equality.
false
if the receiver object is equivalent to the argument; true
otherwise.
o == arg0
is the same as if (o eq null) arg0 eq null else o.equals(arg0)
.
o == arg0
is the same as if (o eq null) arg0 eq null else o.equals(arg0)
.
the object to compare against this object for equality.
true
if the receiver object is equivalent to the argument; false
otherwise.
o == arg0
is the same as o.equals(arg0)
.
o == arg0
is the same as o.equals(arg0)
.
the object to compare against this object for equality.
true
if the receiver object is equivalent to the argument; false
otherwise.
Check to see if a Boolean
property on the specified object, objectWithProperty
, matches its
expected value, and report the result in
the returned BePropertyMatchResult
. The objectWithProperty
is
usually the value to the left of a should
or must
invocation. For example, tempFile
would be passed as the objectWithProperty
in:
Check to see if a Boolean
property on the specified object, objectWithProperty
, matches its
expected value, and report the result in
the returned BePropertyMatchResult
. The objectWithProperty
is
usually the value to the left of a should
or must
invocation. For example, tempFile
would be passed as the objectWithProperty
in:
tempFile should be a (file)
the object with the Boolean
property against which to match
the BePropertyMatchResult
that represents the result of the match
This method is used to cast the receiver object to be of type T0
.
This method is used to cast the receiver object to be of type T0
.
Note that the success of a cast at runtime is modulo Scala's erasure semantics. Therefore the expression
1.asInstanceOf[String]
will throw a ClassCastException
at runtime, while the expression
List(1).asInstanceOf[List[String]]
will not. In the latter example, because the type argument is erased as
part of compilation it is not possible to check whether the contents of the list are of the requested typed.
the receiver object.
This method creates and returns a copy of the receiver object.
This method creates and returns a copy of the receiver object.
The default implementation of the clone
method is platform dependent.
a copy of the receiver object.
Compose this BePropertyMatcher
with the passed function, returning a new BePropertyMatcher
.
Compose this BePropertyMatcher
with the passed function, returning a new BePropertyMatcher
.
This method overrides compose
on Function1
to
return a more specific function type of BePropertyMatcher
.
This method is used to test whether the argument (arg0
) is a reference to the
receiver object (this
).
This method is used to test whether the argument (arg0
) is a reference to the
receiver object (this
).
The eq
method implements an [http://en.wikipedia.org/wiki/Equivalence_relation equivalence relation] on
non-null instances of AnyRef
:
* It is reflexive: for any non-null instance x
of type AnyRef
, x.eq(x)
returns true
.
* It is symmetric: for any non-null instances x
and y
of type AnyRef
, x.eq(y)
returns true
if and
only if y.eq(x)
returns true
.
* It is transitive: for any non-null instances x
, y
, and z
of type AnyRef
if x.eq(y)
returns true
and y.eq(z)
returns true
, then x.eq(z)
returns true
.
Additionally, the eq
method has three other properties.
* It is consistent: for any non-null instances x
and y
of type AnyRef
, multiple invocations of
x.eq(y)
consistently returns true
or consistently returns false
.
* For any non-null instance x
of type AnyRef
, x.eq(null)
and null.eq(x)
returns false
.
* null.eq(null)
returns true
.
When overriding the equals
or hashCode
methods, it is important to ensure that their behavior is
consistent with reference equality. Therefore, if two objects are references to each other (o1 eq o2
), they
should be equal to each other (o1 == o2
) and they should hash to the same value (o1.hashCode == o2.hashCode
).
the object to compare against this object for reference equality.
true
if the argument is a reference to the receiver object; false
otherwise.
This method is used to compare the receiver object (this
) with the argument object (arg0
) for equivalence.
This method is used to compare the receiver object (this
) with the argument object (arg0
) for equivalence.
The default implementations of this method is an [http://en.wikipedia.org/wiki/Equivalence_relation equivalence
relation]:
* It is reflexive: for any instance x
of type Any
, x.equals(x)
should return true
.
* It is symmetric: for any instances x
and y
of type Any
, x.equals(y)
should return true
if and
only if y.equals(x)
returns true
.
* It is transitive: for any instances x
, y
, and z
of type AnyRef
if x.equals(y)
returns true
and
y.equals(z)
returns true
, then x.equals(z)
should return true
.
If you override this method, you should verify that your implementation remains an equivalence relation.
Additionally, when overriding this method it is often necessary to override hashCode
to ensure that objects
that are "equal" (o1.equals(o2)
returns true
) hash to the same scala.Int
(o1.hashCode.equals(o2.hashCode)
).
the object to compare against this object for equality.
true
if the receiver object is equivalent to the argument; false
otherwise.
This method is called by the garbage collector on the receiver object when garbage collection determines that there are no more references to the object.
This method is called by the garbage collector on the receiver object when garbage collection determines that there are no more references to the object.
The details of when and if the finalize
method are invoked, as well as the interaction between finalize
and non-local returns and exceptions, are all platform dependent.
Returns a representation that corresponds to the dynamic class of the receiver object.
Returns a representation that corresponds to the dynamic class of the receiver object.
The nature of the representation is platform dependent.
a representation that corresponds to the dynamic class of the receiver object.
Returns a hash code value for the object.
Returns a hash code value for the object.
The default hashing algorithm is platform dependent.
Note that it is allowed for two objects to have identical hash codes (o1.hashCode.equals(o2.hashCode)
) yet
not be equal (o1.equals(o2)
returns false
). A degenerate implementation could always return 0
.
However, it is required that if two objects are equal (o1.equals(o2)
returns true
) that they have
identical hash codes (o1.hashCode.equals(o2.hashCode)
). Therefore, when overriding this method, be sure
to verify that the behavior is consistent with the equals
method.
the hash code value for the object.
This method is used to test whether the dynamic type of the receiver object is T0
.
This method is used to test whether the dynamic type of the receiver object is T0
.
Note that the test result of the test is modulo Scala's erasure semantics. Therefore the expression
1.isInstanceOf[String]
will return false
, while the expression List(1).isInstanceOf[List[String]]
will
return true
. In the latter example, because the type argument is erased as part of compilation it is not
possible to check whether the contents of the list are of the requested typed.
true
if the receiver object is an instance of erasure of type T0
; false
otherwise.
o.ne(arg0)
is the same as !(o.eq(arg0))
.
o.ne(arg0)
is the same as !(o.eq(arg0))
.
the object to compare against this object for reference dis-equality.
false
if the argument is not a reference to the receiver object; true
otherwise.
Wakes up a single thread that is waiting on the receiver object's monitor.
Wakes up a single thread that is waiting on the receiver object's monitor.
Wakes up all threads that are waiting on the receiver object's monitor.
Wakes up all threads that are waiting on the receiver object's monitor.
Returns a string representation of the object.
Returns a string representation of the object.
The default representation is platform dependent.
a string representation of the object.
Trait extended by matcher objects, which may appear after the word
be
, that can match against aBoolean
property. The match will succeed if and only if theBoolean
property equalstrue
. The object containing the property, which must be of the type specified by theBePropertyMatcher
's type parameterT
, is passed to theBePropertyMatcher
'sapply
method. The result is aBePropertyMatchResult
. ABePropertyMatcher
is, therefore, a function from the specified type,T
, to aBePropertyMatchResult
.Although
BePropertyMatcher
andMatcher
represent similar concepts, they have no inheritance relationship becauseMatcher
is intended for use right aftershould
ormust
whereasBePropertyMatcher
is intended for use right afterbe
.A
BePropertyMatcher
essentially allows you to write statically typedBoolean
property assertions similar to the dynamic ones that use symbols:One good way to organize custom matchers is to place them inside one or more traits that you can then mix into the suites or specs that need them. Here's an example that includes two
BePropertyMatcher
s:Because the type parameter of these two
BePropertyMatcher
s isjava.io.File
, they can only be used with instances of that type. (The compiler will enforce this.) All they do is create aBePropertyMatchResult
whosematches
field istrue
if and only if theBoolean
property istrue
. The second field,propertyName
, is simply the string name of the property. Thefile
anddirectory
val
s create variables that can be used in matcher expressions that test whether ajava.io.File
is a file or a directory. Here's an example:These matches should succeed, but if for example the first match,
tempFile should be a (file)
, were to fail, you would get an error message like:For more information on
BePropertyMatchResult
and the meaning of its fields, please see the documentation forBePropertyMatchResult
. To understand whyBePropertyMatcher
is contravariant in its type parameter, see the section entitled "Matcher's variance" in the documentation forMatcher
.