Flix Assertions#

Various additional assertions for the Flix programming language.

• Latest Version
• Usage
  • Example
  • Infix Format
  • Emptiness
• Changes
• Build targets
• License

Latest Version#

See the latest GitHub Release

Usage#

Add the following stanza to your flix.toml:

[dependencies]
"github:Release-Candidate/flix-assertions" = "0.2.0"

Available assertions:

• Equality:
  • ==: FlixAssertion.eq, FlixAssertion.$==
  • !=: FlixAssertion.neq, FlixAssertion.$!=
• Ordering:
  • >: FlixAssertion.gt, FlixAssertion.$>
  • >=: FlixAssertion.gte, FlixAssertion.$>=
  • <: FlixAssertion.lt, FlixAssertion.$<
  • <=: FlixAssertion.lte, FlixAssertion.$<=
• Tests for emptiness, for types like List or Map:
  • FlixAssertion.isEmpty
  • FlixAssertion.isNotEmpty
• Tests for emptiness, version for mutable types like MutList or Array:
  • FlixAssertion.isEmptyEff
  • FlixAssertion.isNotEmptyEff

Example#

The following failing test

@Test
def test01(): Bool =
    FlixAssertion.eq(3, 1 + 1, "Something went wrong: '1 + 1'")

yields the error:

 FAIL  test01
  Assertion Error: Something went wrong: '1 + 1'
    Expected: 3
    Actual:   2

Infix Format#

The following four examples testEq0[1-4] are the same:

@Test
def testEq01(): Bool =
    FlixAssertion.eq(3, 1 + 1, "Something went wrong: '1 + 1'")

@Test
def testEq02(): Bool =
    use FlixAssertion.{eq};
    "Something went wrong: '1 + 1'" |> (3 `eq` (1 + 1))

@Test
def testEq03(): Bool =
    use FlixAssertion.{eq, <|};
    (3 `eq` (1 + 1)) <| "Something went wrong: '1 + 1'"

@Test
def testEq04(): Bool =
    use FlixAssertion.{$==, <|};
    (3 $== (1 + 1)) <| "Something went wrong: '1 + 1'"

For more examples see the test source file ./test/TestMain.flix

Emptiness#

To be able to test your type for emptiness, it must implement the Empty or EmptyEff type class.

The following Flix types already implement one of these:

• Empty:
  • List
  • Vector
  • Chain
  • Map
  • Set
  • Multimap
• EmptyEff:
  • MutList
  • MutSet
  • MutDeque
  • Array
  • MutMap

Examples on how to implement Empty and EmptyEff:

instance Empty[Chain[a]] {

    pub override def isEmpty(x: Chain[a]): Bool = Chain.isEmpty(x)

    pub def name(_: Chain[a]): String = "Chain"

}

instance EmptyEff[MutMap[k, v]] {

    pub override def isEmpty(x: MutMap[k, v, r]): Bool \ r = MutMap.isEmpty(x)

    pub def name(_: MutMap[k, v, r]): String = "MutMap"
}

Changes#

See file ./CHANGELOG.md

Build targets#

The needed commands to build and test the library:

• display help: java -jar flix.jar --help
• open a REPL of the project: java -jar flix.jar repl
• typecheck the project: java -jar flix.jar check
• run the tests: java -jar flix.jar test
• compile sources: java -jar flix.jar build
• generate a Flix package: java -jar flix.jar build-pkg

License#

Flix Assertions is licensed under the Apache 2.0 license, see file ./LICENSE.md