Fixate

Insert fixtures into your ExUnit context in a clean manner.

The docs can be found at https://hexdocs.pm/fixate.

Installation

The package can be installed by adding fixate to your list of dependencies in mix.exs:

def deps do
  [
    {:fixate, "~> 0.1", only: test}
  ]
end

Usage

Start Fixate by adding Fixate.start() to your test/test_helper.exs file.

  ExUnit.start()
  Fixate.start()

Then inside your test files add use Fixate.Case to allow the fixture attribute.

defmodule MyAppTest do
  use ExUnit.Case
  use Fixate.Case
...

Now you can load fixtures before each test using the @fixture attribute. The attribute takes either a "path" or a key: "path" values. If no key is provided the key will be generated using the base filename before the first dot. The files will be loaded from your priv/fixtures folder.

  @fixture "text.txt"
  @fixture named_text: "text.txt"
  @fixture "subdirectory/subtext.txt"
  test "Reads basic files", ctx do
    assert "FILE_BODY" == ctx.text
    assert ctx.text == ctx.named_text
    assert "FILE_BODY_IN_SUBFOLDER" == ctx.subtext
  end

Adding parsers for fixtures

By default Fixate will simply load the file as a binary. However this is unlikely to be enough for most tests. Instead of Fixate trying to support various file types we give you a simple way to define parsers for files by their "full" extensions.

To do this add parsers to your test/test_helper.exs using the Fixate.add_parser/2 command.

ExUnit.start()
Fixate.start()

# This will be used to parse all *.integer.txt files
Fixate.add_parser("integer.txt", &( String.to_integer(&1) ))

# This will be used to parse all *.json files
Fixate.add_parser("json", &( Jason.decode!(&1) ))

# This will be used to parse all *.geojson.json files
Fixate.add_parser("geojson.json", &( Jason.decode!(&1) |> Geo.JSON.decode! ))

And now the parsed values will appear instead of the binary data

defmodule MyAppTest do
  use ExUnit.Case
  use Fixate.Case

  @fixture "text.txt"
  @fixture "text2.txt"
  test "reads basic files", ctx do
    assert "FILE_BODY" == ctx.text
    assert "OTHER_BODY" == ctx.text
  end

  @fixture answer: "answer_to_everything.integer.txt"
  test "has all the answers", ctx do
    assert 42 == ctx.answer
  end

  @fixture myhouse: "geo/location.geojson.json"
  test "locations", ctx do
    assert MyApp.get_home == ctx.myhouse
  end


end

For more complex parsers create a module, for example in test/support, and reference it.

Fixate.add_parser("complex.xml", &MyFixtureParser.parse_complex/1)

Examples

For an example of usage in an actual project check out Geo.Turf's tests.