org.scalatest

Informer

trait Informer extends AnyRef

Trait to which custom information about a running suite of tests can be reported.

An Informer is essentially used to wrap a Reporter and provide easy ways to send custom information to that Reporter via an InfoProvided event. Informer contains an apply method that takes an object. The Informer will invoke toString on the passed object and forward the resulting string to the Reporter as the message parameter of an InfoProvided event.

Here's an example of using an Informer in a Suite subclass:

import org.scalatest._

class MySuite extends Suite { def testAddition(info: Informer) { assert(1 + 1 === 2) info("Addition seems to work") } }

If you run this Suite from the interpreter, you will see the message included in the printed report:

scala> (new MySuite).execute()
Test Starting - MySuite.testAddition(Reporter)
Info Provided - MySuite.testAddition(Reporter): Addition seems to work
Test Succeeded - MySuite.testAddition(Reporter)

Traits FunSuite, Spec, FlatSpec, WordSpec, FeatureSpec, and their sister traits in org.scalatest.fixture package declare an implicit info method that returns an Informer. This implicit info is used, for example, to enable the syntax offered by the GivenWhenThen trait, which contains methods that take an implicit Informer. Here's an example of a FeatureSpec that mixes in GivenWhenThen:

import org.scalatest.FeatureSpec
import org.scalatest.GivenWhenThen

class ArithmeticSpec extends FeatureSpec with GivenWhenThen {

feature("Integer arithmetic") {

scenario("addition") {

given("two integers") val x = 2 val y = 3

when("they are added") val sum = x + y

then("the result is the sum of the two numbers") assert(sum === 5) }

scenario("subtraction") {

given("two integers") val x = 7 val y = 2

when("one is subtracted from the other") val diff = x - y

then("the result is the difference of the two numbers") assert(diff === 5) } } }

Were you to run this FeatureSpec in the interpreter, you would see the following messages included in the printed report:

scala> (new ArithmeticFeatureSpec).run()
Feature: Integer arithmetic
  Scenario: addition
    Given two integers
    When they are added
    Then the result is the sum of the two numbers
  Scenario: subtraction
    Given two integers
    When one is subtracted from the other
    Then the result is the difference of the two numbers

Inherits

  1. AnyRef
  2. Any

Value Members

  1. def apply(message: String): Unit

    Provide information to the Reporter as the

    Provide information to the Reporter as the .

    message

    an object whose toString result will be forwarded to the wrapped Reporter via an InfoProvided event.

    attributes: abstract
  2. def equals(arg0: Any): Boolean

    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 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 Int (o1.hashCode.equals(o2.hashCode)).

    arg0

    the object to compare against this object for equality.

    returns

    true if the receiver object is equivalent to the argument; false otherwise.

    definition classes: AnyRef ⇐ Any
  3. def hashCode(): Int

    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.

    definition classes: AnyRef ⇐ Any
  4. def toString(): String

    Returns a string representation of the object

    Returns a string representation of the object.

    The default representation is platform dependent.

    definition classes: AnyRef ⇐ Any