Scalactic 3.2.17/org.scalactic/Explicitly

Explicitly

trait Explicitly

Provides ScalaTest's “explicitly DSL,” which facilitates the explicit specification of an Equality[T] or a Uniformity[T] where Equality[T] is taken implicitly.

The Explicitly DSL can be used with the === and !== operators of Scalactic as well as the should equal, be, contain, and === syntax of ScalaTest matchers.

If you want to customize equality for a type in general, you would likely want to place an implicit Equality[T] for that type in scope (or in T's companion object). That implicit equality definition will then be picked up and used when that type is compared for equality with the equal, be, and contain matchers in ScalaTest tests and with === in both tests and production code. If you just want to use a custom equality for a single comparison, however, you may prefer to pass it explicitly. For example, if you have an implicit Equality[String] in scope, you can force a comparison to use the default equality with this syntax:

// In production code:
if ((result === "hello")(decided by defaultEquality)) true else false

// In tests:
result should equal ("hello") (decided by defaultEquality)

The explicitly DSL also provides support for specifying a one-off equality that is based on a normalization. For example, Scalactic offers a StringNormalizations trait that provides methods such as trimmed and lowerCased that return Normalization[String] instances that normalize by trimming and lower-casing, respectively. If you bring those into scope by mixing in or importing the members of StringNormalizations, you could use the explicitly DSL like this:

// In production code:
if ((result === "hello")(after being lowerCased)) true else false

// In tests:
result should equal ("hello") (after being lowerCased and trimmed)

If you prefer not to use English-like DSLs in your production code, you can alternatively not use the Explicitly trait and instead write:

// To explicitly specify an Equality instance, just specify it:
if ((result === "hello")(Equality.default)) true else false

// To base an Equality instance on a Uniformity, just
// call toEquality on it:
if ((result === "hello")(lowerCased.toEquality)) true else false
Companion:
object
Source:
Explicitly.scala
class Object
trait Matchable
class Any
object Explicitly.type

Type members

Classlikes

class DecidedByEquality[A](equality: Equality[A]) extends Equality[A]

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 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)
Source:
Explicitly.scala
class DecidedWord

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.

Source:
Explicitly.scala
class DeterminedByEquivalence[T](equivalence: Equivalence[T]) extends Equivalence[T]

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)
Source:
Explicitly.scala
class DeterminedWord

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.

Source:
Explicitly.scala
class TheAfterWord

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.

Source:
Explicitly.scala

Value members

Concrete fields

val after: TheAfterWord

This field enables syntax such as the following:

This field enables syntax such as the following:

result should equal ("hello") (after being lowerCased)
                              ^
Source:
Explicitly.scala
val decided: DecidedWord

This field enables syntax such as the following:

This field enables syntax such as the following:

result should equal ("hello") (decided by defaultEquality)
                              ^
Source:
Explicitly.scala
val determined: DeterminedWord

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

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

result should equal ("hello") (determined by myStringEquivalence)
                              ^
Source:
Explicitly.scala