Importer addSearchPath("../iospec")
doFile("../iospec/context.io")

doFile("fold.io")

context("empty list",
    setup(
        e := list
    )

    specify("should foldl/1 to nil",
        e foldl(+) should be(nil)
    )

    specify("should foldr/1 to nil",
        e foldr(+) should be(nil)
    )

    specify("should foldl/3 to nil",
        e foldl(x, y, x + y) should be(nil)
    )

    specify("should foldr/3 to nil",
        e foldr(x, y, x + y) should be(nil)
    )
)

context("single elemnt list",
    setup(
        value := 42
        s := list(value)
    )

    specify("should support one argument foldl",
        s foldl(-) should be(value)
    )

    specify("should support three argument foldl",
        s foldl(x, y, x - y) should be(value)
    )

    specify("should support one argument foldr",
        s foldr(-) should be(value)
    )

    specify("should support three argument foldr",
        s foldr(x, y, x - y) should be(value)
    )
)

context("four element list",
    setup(
        a := list(6, 2, 1, 9)
    )

    specify("should support one argument foldl",
        a foldl(-) should be(-6)
    )

    specify("should support three argument foldl",
        a foldl(x, y, x - y) should be(-6)
    )

    specify("should support one argument foldr",
        a foldr(-) should be(-4)
    )

    specify("should support three argument foldr",
        a foldr(x, y, x - y) should be(-4)
    )
)