Type Members

1.  trait DiagrammedExpr[T] extends AnyRef

   A trait that represent an expression recorded by DiagrammedExprMacro, which includes the following members:

   A trait that represent an expression recorded by DiagrammedExprMacro, which includes the following members:

   • a boolean value
   • an anchor that records the position of this expression
   • anchor values of this expression (including sub-expressions)

   DiagrammedExpr is used by code generated from DiagrammedAssertionsMacro, it needs to be public so that the generated code can be compiled. It is expected that ScalaTest users would ever need to use DiagrammedExpr directly.

2.  trait Diagrams extends Assertions

   Sub-trait of Assertions that overrides assert and assume methods to include a diagram showing the values of expression in the error message when the assertion or assumption fails.

   Sub-trait of Assertions that overrides assert and assume methods to include a diagram showing the values of expression in the error message when the assertion or assumption fails.

   Here are some examples:

   scala> import org.scalatest.diagrams.Diagrams._
   import org.scalatest.diagrams.Diagrams._
   
   scala> assert(a == b || c >= d)
   org.scalatest.exceptions.TestFailedException:
   
   assert(a == b || c >= d)
          | |  | |  | |  |
          1 |  2 |  3 |  4
            |    |    false
            |    false
            false
   
           at org.scalatest.Assertions$class.newAssertionFailedException(Assertions.scala:422)
           ...
   
   scala> assert(xs.exists(_ == 4))
   org.scalatest.exceptions.TestFailedException:
   
   assert(xs.exists(_ == 4))
          |  |
          |  false
          List(1, 2, 3)
   
           at org.scalatest.Assertions$class.newAssertionFailedException(Assertions.scala:422)
           ...
   
   scala> assert("hello".startsWith("h") && "goodbye".endsWith("y"))
   org.scalatest.exceptions.TestFailedException:
   
   assert("hello".startsWith("h") && "goodbye".endsWith("y"))
          |       |          |    |  |         |        |
          "hello" true       "h"  |  "goodbye" false    "y"
                                  false
   
           at org.scalatest.Assertions$class.newAssertionFailedException(Assertions.scala:422)
           ...
   
   scala> assert(num.isInstanceOf[Int])
   org.scalatest.exceptions.TestFailedException:
   
   assert(num.isInstanceOf[Int])
          |   |
          1.0 false
   
           at org.scalatest.Assertions$class.newAssertionFailedException(Assertions.scala:422)
           ...
   
   scala> assert(Some(2).isEmpty)
   org.scalatest.exceptions.TestFailedException:
   
   assert(Some(2).isEmpty)
          |    |  |
          |    2  false
          Some(2)
   
           at org.scalatest.Assertions$class.newAssertionFailedException(Assertions.scala:422)
           ...
   
   scala> assert(None.isDefined)
   org.scalatest.exceptions.TestFailedException:
   
   assert(None.isDefined)
          |    |
          None false
   
           at org.scalatest.Assertions$class.newAssertionFailedException(Assertions.scala:422)
           ...
   
   scala> assert(xs.exists(i => i > 10))
   org.scalatest.exceptions.TestFailedException:
   
   assert(xs.exists(i => i > 10))
          |  |
          |  false
          List(1, 2, 3)
   
           at org.scalatest.Assertions$class.newAssertionFailedException(Assertions.scala:422)
           ...
   
   

   If the expression passed to assert or assume spans more than one line, Diagrams falls back to the default style of error message, since drawing a diagram would be difficult. Here's an example showing how Diagrams will treat a multi-line assertion (i.e., you don't get a diagram):

   scala> assert("hello".startsWith("h") &&
        |   "goodbye".endsWith("y"))
   org.scalatest.exceptions.TestFailedException: "hello" started with "h", but "goodbye" did not end with "y"
           at org.scalatest.Assertions$class.newAssertionFailedException(Assertions.scala:422)
           ...
   

   Also, since an expression diagram essentially represents multi-line ascii art, if a clue string is provided, it appears above the diagram, not after it. It will often also show up in the diagram:

   scala> assert(None.isDefined, "Don't do this at home")
   org.scalatest.exceptions.TestFailedException: Don't do this at home
   
   assert(None.isDefined, "Don't do this at home")
          |    |
          None false
   
           at org.scalatest.Assertions$class.newAssertionFailedException(Assertions.scala:422)
           ...
   
   scala> assert(None.isDefined,
        |   "Don't do this at home")
   org.scalatest.exceptions.TestFailedException: Don't do this at home
   
   assert(None.isDefined,
          |    |
          None false
   
           at org.scalatest.Assertions$class.newAssertionFailedException(Assertions.scala:422)
           ...
   

   Trait Diagrams was inspired by Peter Niederwieser's work in Spock and Expecty.