AnyUnit.Style.FSharp 1.2.0

AnyUnit.Style.FSharp

F#'s own idiomatic, value-based test style for AnyUnit - a test is a Test value built with the test { } computation expression, not a [Test]- attributed instance method the way AnyUnit.Style.Nunit/ AnyUnit.Style.Xunit/AnyUnit.Style.FsUnit all work. If your F# test suite already reaches for real NUnit/xUnit's attribute style, use one of those instead - reach for this one when a top-level let reads more naturally than a class full of [Test] methods.

Usage

[<assembly: AnyUnit.Style.FSharp.FSharpStyle>]
do ()

open AnyUnit.Style.FSharp.Test

// Either shape is discovered - a plain value binding, or a real
// zero-argument function (the two idiomatic ways to write "just a test,
// no parameters" in F#):
let ``adds two numbers`` = test {
    let! Assert = assertion
    Assert.Equal(4, 2 + 2)
}

let ``adds two numbers, function form`` () = test {
    let! Assert = assertion
    Assert.Equal(4, 2 + 2)
}

let! Assert = assertion binds the current test's IAssert - call straight into whichever style's assertion vocabulary you already have referenced (AnyUnit.Style.Xunit's Assert.Equal/Assert.True/..., AnyUnit.Constraints' Assert.That(x, Is.EqualTo(y)), ...): this package doesn't provide its own. let! log = AnyUnit.Style.FSharp.Test.log gets the test's ILog (captured output) the same way.

A test is discovered by its own let binding name - there's no separate description string to also keep in sync.

Parameterized tests

This style has no data attribute of its own by design (a Test is a value, not a method with parameters an attribute could sit on) - a real F# function (with real parameters, so it compiles to a genuine method, not a property) carrying another style's row attribute works instead, since Test-typed function discovery recognizes any attribute implementing AnyUnit.Run.Attributes.IRowInlineParameter:

open AnyUnit.Style.FSharp.Test
open AnyUnit.Style.Xunit // for InlineDataAttribute - any style's own row attribute works the same way

[<InlineData(1, 1)>]
[<InlineData(2, 4)>]
[<InlineData(3, 9)>]
let square (n: int) (expected: int) = test {
    let! Assert = assertion
    Assert.True(n * n = expected, $"Expected {n}*{n} = {expected}")
}

Each row runs as its own, separately-reported test - same as [TestCase]/ [InlineData] under the attribute-based styles.