Blog.RecursiveTypes.InvalidTestScenarios.fs

open FsCheck

module Gen =
  module FolderDto =
    let tooWide =
      tree 0 maxDepth 10 10 (fun xs -> 
        Folder.id 
        |> Gen.map (fun x -> Tree.create x.Value xs))
      |> Gen.filter (fun t -> t.Branches <> [])
      |> Gen.map treeToDto

    let tooDeep =
      tree 5 10 1 maxWidth (fun xs -> 
        Folder.id 
        |> Gen.map (fun x -> Tree.create x.Value xs))
      |> Gen.scaleSize ((+) (maxDepth + 1))
      |> Gen.map treeToDto

    let duplicates = gen {
      let! duplicateRoot = 
        Folder.id |> Gen.map (fun id -> 
          [ folderDto_withoutParent id.Value None
            folderDto_withoutParent id.Value None ])

    let! duplicateSub = 
      Gen.map Alphanum10.value Folder.id 
      |> Gen.two |> Gen.map (fun (x, y) -> 
        [ folderDto_withParent x None y
          folderDto_withParent x None y ])
    
    return List.concat [ duplicateRoot; duplicateSub ] }

    let recurseItem =
      Folder.id
      |> Gen.map (Alphanum10.value >> fun id -> folderDto_withParent id None id)
      |> Gen.nonEmptyListOf