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•  package org

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•  package scalatest

  ScalaTest's main traits, classes, and other members, including members supporting ScalaTest's DSL for the Scala interpreter.

  ScalaTest's main traits, classes, and other members, including members supporting ScalaTest's DSL for the Scala interpreter.

  Definition Classes

  org

•  trait OptionValues extends AnyRef

  Trait that provides an implicit conversion that adds a value method to Option, which will return the value of the option if it is defined, or throw TestFailedException if not.

  Trait that provides an implicit conversion that adds a value method to Option, which will return the value of the option if it is defined, or throw TestFailedException if not.

  This construct allows you to express in one statement that an option should be defined and that its value should meet some expectation. Here's an example:

  opt.value should be > 9
  

  Or, using an assertion instead of a matcher expression:

  assert(opt.value > 9)
  

  Were you to simply invoke get on the Option, if the option wasn't defined, it would throw a NoSuchElementException:

  val opt: Option[Int] = None
  
  opt.get should be > 9 // opt.get throws NoSuchElementException
  

  The NoSuchElementException would cause the test to fail, but without providing a stack depth pointing to the failing line of test code. This stack depth, provided by TestFailedException (and a few other ScalaTest exceptions), makes it quicker for users to navigate to the cause of the failure. Without OptionValues, to get a stack depth exception you would need to make two statements, like this:

  val opt: Option[Int] = None
  
  opt should be ('defined) // throws TestFailedException
  opt.get should be > 9
  

  The OptionValues trait allows you to state that more concisely:

  val opt: Option[Int] = None
  
  opt.value should be > 9 // opt.value throws TestFailedException
  

  Definition Classes

  scalatest

• Valuable

org.scalatest.OptionValues

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