death-socket/TestCentre/LibraryTests.fs

namespace LibraryTests

    (* Initial Setup -- Populating the Test Folders.
    ===========================================================================
    If you have just cloned this repository or have not run any of the tests
    before, please head over to script.fs (in Test Centre) and populate the
    LoadingTestArea and SavingTestArea folders. More information will be
    provided there about what the scripts do. It is worth pointing out here the
    .gitignore file ignores any .png files in them. This is why you must
    populate them before running any tests. *)

    module TestingHelpers =

        (* When you are writing tests, please keep all helper functions in this
        module. If this module grows to a point where it hinders the actual
        testing modules, consider moving it then. If you do decide to move them
        out, pay attention to ConsoleTests.fs and its helper functions. *)

        open System
        open System.Drawing
        open System.Reflection
        open System.IO

        (* These are duplicates from ConsoleTests.fs (both of them). See point
        about helpers. Tests for checking these locations can be found in
        ConsoleTests.fs.*)
        let loadLocation = __SOURCE_DIRECTORY__ + "/LoadingTestArea"
        let saveLocation  = __SOURCE_DIRECTORY__ + "/SavingTestArea"

        let allColours =
            let properties =
                typeof<Brushes>.GetProperties
                    (BindingFlags.Public ||| BindingFlags.Static)
            seq { for prop in properties -> prop}
            |> Seq.toArray

        let randomBrush () =
            let item = allColours.[Random().Next(allColours.Length)]
            item.GetValue(null, null)

        let imagesInLoadingTestArea =
            Directory.GetFileSystemEntries (loadLocation, "*.png")

        let generateLoadPath () =
            let rand = Random ()
            let files = imagesInLoadingTestArea
            files.[rand.Next(files.Length)]

        let generateSavePath originalFilePath =
            let fileName = Path.GetFileName originalFilePath
            saveLocation + "/" + fileName

        (* To "manually" clear out the SavingTestArea folder, use this function
        in script.fsx. More information can be found there, also.*)
        let resetSavingTestArea () =
            let files = Directory.GetFileSystemEntries(saveLocation, "*.png")
            match files.Length with
            | 0 -> ()
            | _ ->
                files
                |> Array.iter (fun f -> File.Delete(f))

    module PropertyTests =

        open FsCheck.Xunit
        open DeathSocket
        open System.Drawing
        open DeathSocket.GridPainter
        open TestingHelpers
        open System.IO

        [<Property>]
        let ``Can apply grid to image and save it`` () =
            (* You should end up with one image left over in SavingTestArea.
            Comment out the "reset" function to see all the images produced,
            by this test. This will mean you will need to manually delete the
            images yourself if you do.*)
            resetSavingTestArea ()
            let oPath = generateLoadPath ()
            let sPath = generateSavePath oPath
            let spec =
                { originalPath = oPath
                  savePath = sPath
                  colour = randomBrush () :?> Brush
                  penWidth = float32 1
                  rows = 10
                  columns = 10 }
            applyGrid spec
            |> Async.RunSynchronously
            (File.Exists sPath) = true

    module UnitTests =

        open TestingHelpers
        open Xunit

        (* This test is a precaution (a test for the tests if you will...).
        It is here to make sure the property test has what it needs to run.
        If the property test fails, here is a good place to start.
        See script.fs (in Test Centre) for information on populating the
        LoadingTestArea folder. *)
        [<Fact>]
        let ``LoadingTestArea contains at least 100 test images`` () =
            let length = imagesInLoadingTestArea.Length
            let imagesAreThere = if length < 100 then false else true
            Assert.True imagesAreThere