module ZipperTests open FsUnit.Xunit open Xunit open Zipper let subTree value left right = Some (tree value left right) let leaf value = subTree value None None [] let ``Data is retained`` () = let zipper = fromTree (tree 1 (subTree 2 None (leaf 3)) (leaf 4)) let expected = tree 1 (subTree 2 None (leaf 3)) (leaf 4) let actual = zipper |> toTree actual |> should equal expected [] let ``Left, right and value`` () = let zipper = fromTree (tree 1 (subTree 2 None (leaf 3)) (leaf 4)) let expected = 3 let actual = zipper |> left |> Option.get |> right |> Option.get |> value actual |> should equal expected [] let ``Dead end`` () = let zipper = fromTree (tree 1 (subTree 2 None (leaf 3)) (leaf 4)) let expected = None let actual = zipper |> left |> Option.get |> left actual |> should equal expected [] let ``Tree from deep focus`` () = let zipper = fromTree (tree 1 (subTree 2 None (leaf 3)) (leaf 4)) let expected = tree 1 (subTree 2 None (leaf 3)) (leaf 4) let actual = zipper |> left |> Option.get |> right |> Option.get |> toTree actual |> should equal expected [] let ``Traversing up from top`` () = let zipper = fromTree (tree 1 (subTree 2 None (leaf 3)) (leaf 4)) let expected = None let actual = zipper |> up actual |> should equal expected [] let ``Left, right, and up`` () = let zipper = fromTree (tree 1 (subTree 2 None (leaf 3)) (leaf 4)) let expected = 3 let actual = zipper |> left |> Option.get |> up |> Option.get |> right |> Option.get |> up |> Option.get |> left |> Option.get |> right |> Option.get |> value actual |> should equal expected [] let ``Test ability to descend multiple levels and return`` () = let zipper = fromTree (tree 1 (subTree 2 None (leaf 3)) (leaf 4)) let expected = 1 let actual = zipper |> left |> Option.get |> right |> Option.get |> up |> Option.get |> up |> Option.get |> value actual |> should equal expected [] let ``Set value`` () = let zipper = fromTree (tree 1 (subTree 2 None (leaf 3)) (leaf 4)) let expected = tree 1 (subTree 5 None (leaf 3)) (leaf 4) let actual = zipper |> left |> Option.get |> setValue 5 |> toTree actual |> should equal expected [] let ``Set value after traversing up`` () = let zipper = fromTree (tree 1 (subTree 2 None (leaf 3)) (leaf 4)) let expected = tree 1 (subTree 5 None (leaf 3)) (leaf 4) let actual = zipper |> left |> Option.get |> right |> Option.get |> up |> Option.get |> setValue 5 |> toTree actual |> should equal expected [] let ``Set left with leaf`` () = let zipper = fromTree (tree 1 (subTree 2 None (leaf 3)) (leaf 4)) let expected = tree 1 (subTree 2 (leaf 5) (leaf 3)) (leaf 4) let actual = zipper |> left |> Option.get |> setLeft (Some (tree 5 None None)) |> toTree actual |> should equal expected [] let ``Set right with null`` () = let zipper = fromTree (tree 1 (subTree 2 None (leaf 3)) (leaf 4)) let expected = tree 1 (leaf 2) (leaf 4) let actual = zipper |> left |> Option.get |> setRight None |> toTree actual |> should equal expected [] let ``Set right with subtree`` () = let zipper = fromTree (tree 1 (subTree 2 None (leaf 3)) (leaf 4)) let expected = tree 1 (subTree 2 None (leaf 3)) (subTree 6 (leaf 7) (leaf 8)) let actual = zipper |> setRight (Some (tree 6 (leaf 7) (leaf 8))) |> toTree actual |> should equal expected [] let ``Set value on deep focus`` () = let zipper = fromTree (tree 1 (subTree 2 None (leaf 3)) (leaf 4)) let expected = tree 1 (subTree 2 None (leaf 5)) (leaf 4) let actual = zipper |> left |> Option.get |> right |> Option.get |> setValue 5 |> toTree actual |> should equal expected [] let ``Different paths to same zipper`` () = let zipper = fromTree (tree 1 (subTree 2 None (leaf 3)) (leaf 4)) let expected = fromTree (tree 1 (subTree 2 None (leaf 3)) (leaf 4)) |> right let actual = zipper |> left |> Option.get |> up |> Option.get |> right actual |> should equal expected