Approval Testing Framework for Elixir

Status - Work in Progress

This is very early days.

Currently the code consists of a couple of helper functions you can use to run an approval test inside a unit test. It has no line by line comparitor yet. I am simply using a diff plugin.

A test looks something like the one below.

The input builder is a hook function that assembles the parameters to call the SUT (System Under Test) with.
The test data is a Keyword that holds the various values that exercise the corner cases.
ExApproval.gen_test_data_set(test_data_set, input_builder) creates a list of parameter sets that contains all the permutations of the test data.
All the file writing and comparing files is still in the test.

# If you want to set up special output file names you can define the parts here
# otherwise they default to the test file name.
# def config do
#   %Approvals{
#     project_name: "approval_tests",
#     test_name: "example_test",
#     file_extension: "txt",
#     file_path: "test"
#   }
# end
test "Example approvals test" do
  input_builder = fn %{name: name, sell_in: sell_in, quality: quality} ->
    %Item{name: name, sell_in: sell_in, quality: quality}
  end
  test_data =
    [
      name: [
        "Others",
        "Aged Brie",
        "Backstage passes to a TAFKAL80ETC concert",
        "Sulfuras, Hand of Ragnaros"
      ],
      sell_in: [-1, 0, 1, 10, 50],
      quality: [0, 1, 49, 50]
    ]
    |> Approvals.gen_test_data_set(input_builder)
  GuildedRose.update_quality(test_data)
  |> Approvals.verify()
end

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