Class used via an implicit conversion to enable any two objects to be compared with
=== in assertions in tests. For example:
assert(a === b)
The benefit of using assert(a === b) rather than assert(a == b) is
that a TestFailedException produced by the former will include the values of a and b
in its detail message.
The implicit method that performs the conversion from Any to Equalizer is
convertToEqualizer in trait Assertions.
In case you're not familiar with how implicit conversions work in Scala, here's a quick explanation.
The convertToEqualizer method in Assertions is defined as an "implicit" method that takes an
Any, which means you can pass in any object, and it will convert it to an Equalizer.
The Equalizer has === defined. Most objects don't have === defined as a method
on them. Take two Strings, for example:
assert("hello" === "world")
Given this code, the Scala compiler looks for an === method on class String, because that's the class of
"hello". String doesn't define ===, so the compiler looks for an implicit conversion from
String to something that does have an === method, and it finds the convertToEqualizer method. It
then rewrites the code to this:
assert(convertToEqualizer("hello").===("world"))
So inside a Suite (which mixes in Assertions, === will work on anything. The only
situation in which the implicit conversion wouldn't
happen is on types that have an === method already defined.
The primary constructor takes one object, left, whose type is being converted to Equalizer. The left
value may be a null reference, because this is allowed by Scala's == operator.
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.
The === operation compares this Equalizer's left value (passed
to the constructor, usually via an implicit conversion) with the passed right value
for equality as determined by the expression left == right.
The === operation compares this Equalizer's left value (passed
to the constructor, usually via an implicit conversion) with the passed right value
for equality as determined by the expression left == right.
If true, === returns None. Else, === returns
a Some whose String value indicates the left and right values.
In its typical usage, the Option[String] returned by === will be passed to one of two
of trait Assertion' overloaded assert methods. If None,
which indicates the assertion succeeded, assert will return normally. But if Some is passed,
which indicates the assertion failed, assert will throw a TestFailedException whose detail
message will include the String contained inside the Some, which in turn includes the
left and right values. This TestFailedException is typically embedded in a
Report and passed to a Reporter, which can present the left and right
values to the user.
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.
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.
Class used via an implicit conversion to enable any two objects to be compared with
===in assertions in tests. For example:The benefit of using
assert(a === b)rather thanassert(a == b)is that aTestFailedExceptionproduced by the former will include the values ofaandbin its detail message. The implicit method that performs the conversion fromAnytoEqualizerisconvertToEqualizerin traitAssertions.In case you're not familiar with how implicit conversions work in Scala, here's a quick explanation. The
convertToEqualizermethod inAssertionsis defined as an "implicit" method that takes anAny, which means you can pass in any object, and it will convert it to anEqualizer. TheEqualizerhas===defined. Most objects don't have===defined as a method on them. Take two Strings, for example:assert("hello" === "world")Given this code, the Scala compiler looks for an
===method on classString, because that's the class of"hello".Stringdoesn't define===, so the compiler looks for an implicit conversion fromStringto something that does have an===method, and it finds theconvertToEqualizermethod. It then rewrites the code to this:assert(convertToEqualizer("hello").===("world"))So inside a
Suite(which mixes inAssertions,===will work on anything. The only situation in which the implicit conversion wouldn't happen is on types that have an===method already defined.The primary constructor takes one object,
left, whose type is being converted toEqualizer. Theleftvalue may be anullreference, because this is allowed by Scala's==operator.