GeneratorDrivenPropertyChecks

Implicitly converts PropertyCheckConfigs to PropertyCheckConfiguration, which enables a smoother upgrade path.

Performs a property check by applying the specified property check function to named arguments supplied by the specified generators.

Here's an example:

import org.scalacheck.Gen

// Define your own string generator:
val famousLastWords = for {
  s <- Gen.oneOf("the", "program", "compiles", "therefore", "it", "should", "work")
} yield s

forAll ((famousLastWords, "a"), (famousLastWords, "b"), (famousLastWords, "c"), (famousLastWords, "d"), (famousLastWords, "e"), (famousLastWords, "f")) { (a: String, b: String, c: String, d: String, e: String, f: String) =>
  a.length + b.length + c.length + d.length + e.length + f.length should equal ((a + b + c + d + e + f).length)
}

Performs a property check by applying the specified property check function to arguments supplied by the specified generators.

Here's an example:

import org.scalacheck.Gen

// Define your own string generator:
val famousLastWords = for {
  s <- Gen.oneOf("the", "program", "compiles", "therefore", "it", "should", "work")
} yield s

forAll (famousLastWords, famousLastWords, famousLastWords, famousLastWords, famousLastWords, famousLastWords) { (a: String, b: String, c: String, d: String, e: String, f: String) =>
  a.length + b.length + c.length + d.length + e.length + f.length should equal ((a + b + c + d + e + f).length)
}

Performs a property check by applying the specified property check function with the specified argument names to arguments supplied by implicitly passed generators.

Here's an example:

forAll ("a", "b", "c", "d", "e", "f") { (a: String, b: String, c: String, d: String, e: String, f: String) =>
  a.length + b.length + c.length + d.length + e.length + f.length should equal ((a + b + c + d + e + f).length)
}

Performs a property check by applying the specified property check function to arguments supplied by implicitly passed generators.

Here's an example:

forAll { (a: String, b: String, c: String, d: String, e: String, f: String) =>
  a.length + b.length + c.length + d.length + e.length + f.length should equal ((a + b + c + d + e + f).length)
}

Performs a property check by applying the specified property check function to named arguments supplied by the specified generators.

Here's an example:

import org.scalacheck.Gen

// Define your own string generator:
val famousLastWords = for {
  s <- Gen.oneOf("the", "program", "compiles", "therefore", "it", "should", "work")
} yield s

forAll ((famousLastWords, "a"), (famousLastWords, "b"), (famousLastWords, "c"), (famousLastWords, "d"), (famousLastWords, "e")) { (a: String, b: String, c: String, d: String, e: String) =>
  a.length + b.length + c.length + d.length + e.length should equal ((a + b + c + d + e).length)
}

Performs a property check by applying the specified property check function to arguments supplied by the specified generators.

Here's an example:

import org.scalacheck.Gen

// Define your own string generator:
val famousLastWords = for {
  s <- Gen.oneOf("the", "program", "compiles", "therefore", "it", "should", "work")
} yield s

forAll (famousLastWords, famousLastWords, famousLastWords, famousLastWords, famousLastWords) { (a: String, b: String, c: String, d: String, e: String) =>
  a.length + b.length + c.length + d.length + e.length should equal ((a + b + c + d + e).length)
}

Performs a property check by applying the specified property check function with the specified argument names to arguments supplied by implicitly passed generators.

Here's an example:

forAll ("a", "b", "c", "d", "e") { (a: String, b: String, c: String, d: String, e: String) =>
  a.length + b.length + c.length + d.length + e.length should equal ((a + b + c + d + e).length)
}

Performs a property check by applying the specified property check function to arguments supplied by implicitly passed generators.

Here's an example:

forAll { (a: String, b: String, c: String, d: String, e: String) =>
  a.length + b.length + c.length + d.length + e.length should equal ((a + b + c + d + e).length)
}

Performs a property check by applying the specified property check function to named arguments supplied by the specified generators.

Here's an example:

import org.scalacheck.Gen

// Define your own string generator:
val famousLastWords = for {
  s <- Gen.oneOf("the", "program", "compiles", "therefore", "it", "should", "work")
} yield s

forAll ((famousLastWords, "a"), (famousLastWords, "b"), (famousLastWords, "c"), (famousLastWords, "d")) { (a: String, b: String, c: String, d: String) =>
  a.length + b.length + c.length + d.length should equal ((a + b + c + d).length)
}

Performs a property check by applying the specified property check function to arguments supplied by the specified generators.

Here's an example:

import org.scalacheck.Gen

// Define your own string generator:
val famousLastWords = for {
  s <- Gen.oneOf("the", "program", "compiles", "therefore", "it", "should", "work")
} yield s

forAll (famousLastWords, famousLastWords, famousLastWords, famousLastWords) { (a: String, b: String, c: String, d: String) =>
  a.length + b.length + c.length + d.length should equal ((a + b + c + d).length)
}

Performs a property check by applying the specified property check function with the specified argument names to arguments supplied by implicitly passed generators.

Here's an example:

forAll ("a", "b", "c", "d") { (a: String, b: String, c: String, d: String) =>
  a.length + b.length + c.length + d.length should equal ((a + b + c + d).length)
}

Performs a property check by applying the specified property check function to arguments supplied by implicitly passed generators.

Here's an example:

forAll { (a: String, b: String, c: String, d: String) =>
  a.length + b.length + c.length + d.length should equal ((a + b + c + d).length)
}

Performs a property check by applying the specified property check function to named arguments supplied by the specified generators.

Here's an example:

import org.scalacheck.Gen

// Define your own string generator:
val famousLastWords = for {
  s <- Gen.oneOf("the", "program", "compiles", "therefore", "it", "should", "work")
} yield s

forAll ((famousLastWords, "a"), (famousLastWords, "b"), (famousLastWords, "c")) { (a: String, b: String, c: String) =>
  a.length + b.length + c.length should equal ((a + b + c).length)
}

Performs a property check by applying the specified property check function to arguments supplied by the specified generators.

Here's an example:

import org.scalacheck.Gen

// Define your own string generator:
val famousLastWords = for {
  s <- Gen.oneOf("the", "program", "compiles", "therefore", "it", "should", "work")
} yield s

forAll (famousLastWords, famousLastWords, famousLastWords) { (a: String, b: String, c: String) =>
  a.length + b.length + c.length should equal ((a + b + c).length)
}

Performs a property check by applying the specified property check function with the specified argument names to arguments supplied by implicitly passed generators.

Here's an example:

forAll ("a", "b", "c") { (a: String, b: String, c: String) =>
  a.length + b.length + c.length should equal ((a + b + c).length)
}

Performs a property check by applying the specified property check function to arguments supplied by implicitly passed generators.

Here's an example:

forAll { (a: String, b: String, c: String) =>
  a.length + b.length + c.length should equal ((a + b + c).length)
}

Performs a property check by applying the specified property check function to named arguments supplied by the specified generators.

Here's an example:

import org.scalacheck.Gen

// Define your own string generator:
val famousLastWords = for {
  s <- Gen.oneOf("the", "program", "compiles", "therefore", "it", "should", "work")
} yield s

forAll ((famousLastWords, "a"), (famousLastWords, "b")) { (a: String, b: String) =>
  a.length + b.length should equal ((a + b).length)
}

Performs a property check by applying the specified property check function to arguments supplied by the specified generators.

Here's an example:

import org.scalacheck.Gen

// Define your own string generator:
val famousLastWords = for {
  s <- Gen.oneOf("the", "program", "compiles", "therefore", "it", "should", "work")
} yield s

forAll (famousLastWords, famousLastWords) { (a: String, b: String) =>
  a.length + b.length should equal ((a + b).length)
}

Performs a property check by applying the specified property check function with the specified argument names to arguments supplied by implicitly passed generators.

Here's an example:

forAll ("a", "b") { (a: String, b: String) =>
  a.length + b.length should equal ((a + b).length)
}

Performs a property check by applying the specified property check function to arguments supplied by implicitly passed generators.

Here's an example:

forAll { (a: String, b: String) =>
  a.length + b.length should equal ((a + b).length)
}

Performs a property check by applying the specified property check function to named arguments supplied by the specified generators.

Here's an example:

import org.scalacheck.Gen

// Define your own string generator:
val famousLastWords = for {
  s <- Gen.oneOf("the", "program", "compiles", "therefore", "it", "should", "work")
} yield s

forAll ((famousLastWords, "a")) { (a: String) =>
  a.length should equal ((a).length)
}

Performs a property check by applying the specified property check function to arguments supplied by the specified generators.

Here's an example:

import org.scalacheck.Gen

// Define your own string generator:
val famousLastWords = for {
  s <- Gen.oneOf("the", "program", "compiles", "therefore", "it", "should", "work")
} yield s

forAll (famousLastWords) { (a: String) =>
  a.length should equal ((a).length)
}

Performs a property check by applying the specified property check function with the specified argument names to arguments supplied by implicitly passed generators.

Here's an example:

forAll ("a") { (a: String) =>
  a.length should equal ((a).length)
}

Performs a property check by applying the specified property check function to arguments supplied by implicitly passed generators.

Here's an example:

forAll { (a: String) =>
  a.length should equal ((a).length)
}

Performs a property check by applying the specified property check function to arguments supplied by implicitly passed generators, modifying the values in the implicitly passed PropertyGenConfig object with explicitly passed parameter values.

This method creates a ConfiguredPropertyCheck object that has six overloaded apply methods that take a function. Thus it is used with functions of all six arities. Here are some examples:

forAll (minSize(1), maxSize(10)) { (a: String) =>
  a.length should equal ((a).length)
}

forAll (minSize(1), maxSize(10)) { (a: String, b: String) =>
  a.length + b.length should equal ((a + b).length)
}

forAll (minSize(1), maxSize(10)) { (a: String, b: String, c: String) =>
  a.length + b.length + c.length should equal ((a + b + c).length)
}

forAll (minSize(1), maxSize(10)) { (a: String, b: String, c: String, d: String) =>
  a.length + b.length + c.length + d.length should equal ((a + b + c + d).length)
}

forAll (minSize(1), maxSize(10)) { (a: String, b: String, c: String, d: String, e: String) =>
  a.length + b.length + c.length + d.length + e.length should equal ((a + b + c + d + e).length)
}

forAll (minSize(1), maxSize(10)) { (a: String, b: String, c: String, d: String, e: String, f: String) =>
  a.length + b.length + c.length + d.length + e.length + f.length should equal ((a + b + c + d + e + f).length)
}

Implicit PropertyCheckConfig value providing default configuration values.

Returns a MaxDiscardedFactor property check configuration parameter containing the passed value, which specifies the factor of discarded property evaluations allowed during property evaluation.

Returns a MinSize property check configuration parameter containing the passed value, which specifies the minimum size parameter to provide to ScalaCheck, which it will use when generating objects for which size matters (such as strings or lists).

Returns a MinSuccessful property check configuration parameter containing the passed value, which specifies the minimum number of successful property evaluations required for the property to pass.

Returns a SizeRange property check configuration parameter containing the passed value, that (with minSize) specifies the maximum size parameter to provide to ScalaCheck, which it will use when generating objects for which size matters (such as strings or lists).

Note that the size range is added to minSize in order to calculate the maximum size passed to ScalaCheck. Using a range allows compile-time checking of a non-negative number being specified.

Evaluates the passed code block if the passed boolean condition is true, else throws DiscardedEvaluationException.

The whenever method can be used inside property check functions to discard invocations of the function with data for which it is known the property would fail. For example, given the following Fraction class:

class Fraction(n: Int, d: Int) {

  require(d != 0)
  require(d != Integer.MIN_VALUE)
  require(n != Integer.MIN_VALUE)

  val numer = if (d < 0) -1 * n else n
  val denom = d.abs

  override def toString = numer + " / " + denom
}

import org.scalatest.prop.TableDrivenPropertyChecks._

val fractions =
  Table(
    ("n", "d"),
    (  1,   2),
    ( -1,   2),
    (  1,  -2),
    ( -1,  -2),
    (  3,   1),
    ( -3,   1),
    ( -3,   0),
    (  3,  -1),
    (  3,  Integer.MIN_VALUE),
    (Integer.MIN_VALUE, 3),
    ( -3,  -1)
  )

Imagine you wanted to check a property against this class with data that includes some value that are rejected by the constructor, such as a denominator of zero, which should result in an IllegalArgumentException. You could use whenever to discard any rows in the fraction that represent illegal arguments, like this:

import org.scalatest.matchers.ShouldMatchers._

forAll (fractions) { (n: Int, d: Int) =>

  whenever (d != 0 && d != Integer.MIN_VALUE
      && n != Integer.MIN_VALUE) {

    val f = new Fraction(n, d)

    if (n < 0 && d < 0 || n > 0 && d > 0)
      f.numer should be > 0
    else if (n != 0)
      f.numer should be < 0
    else
      f.numer should === (0)

    f.denom should be > 0
  }
}

In this example, rows 6, 8, and 9 have values that would cause a false to be passed to whenever. (For example, in row 6, d is 0, which means d != 0 will be false.) For those rows, whenever will throw DiscardedEvaluationException, which will cause the forAll method to discard that row.

Returns a Workers property check configuration parameter containing the passed value, which specifies the number of worker threads to use when evaluating a property.

Returns a MaxDiscarded property check configuration parameter containing the passed value, which specifies the maximum number of discarded property evaluations allowed during property evaluation.

Returns a MaxSize property check configuration parameter containing the passed value, which specifies the maximum size parameter to provide to ScalaCheck, which it will use when generating objects for which size matters (such as strings or lists).

Note that the maximum size should be greater than or equal to the minimum size. This requirement is enforced by the PropertyCheckConfig constructor and the forAll methods of traits PropertyChecks and Checkers. In other words, it is enforced at the point both a maximum and minimum size are provided together.