View Source Repatch.Expectations (Repatch v1.6.1)

Helpers for working with repatch in an imperative mocking style. See expect/4 for more documentation.

Example

defmodule SuperComputerTest do
  use ExUnit.Case, async: true
  use Repatch.ExUnit, assert_expectations: true

  import Repatch.Expectations

  test "SuperComputer.meaning_of/1" do
    expect(SuperComputer, :meaning_of, fn :life -> 42 end)
    |> expect(fn 42 -> :life end)

    assert SuperComputer.meaning_of(:life) == 42
    assert SuperComputer.meaning_of(42) == :life
  end
end

Summary

Types

expect_option()

Options passed in the expect/4 function.

expectation()

key()

queue()

queues()

Functions

cleanup(queues \\ Process.get(:repatch_expectations_queues))

Performs cleanup of expectations queues. Returns true if queues were found and cleaned up. Returns false if no expectations queues were found

expect(queue, func)

See expect/4

expect(module, name, func)

See expect/4

expect(module, name, opts, func)

Queues up the patch which will be executed once (or multiple times) and then removed from queue. Once all patches are executed, calls to patched function will fail.

expectations_empty?(queues \\ Queues.all())

Checks if there are any expectations empty. Useful in asserts

pending_expectations(queues \\ Queues.all())

Lists all not-yet executed expectations

Types

expect_option()

@type expect_option() :: {:times, pos_integer()} | Repatch.patch_option()

Options passed in the expect/4 function.

exactly (positive integer or once) — If the function is expected to be called this exact amount of times. Defaults to 1.
at_least (non negative integer or once or any) — If the function is expected to be called at least this amount of times. This option works similar to stubs in Mox library.
ignore_forbidden_module (boolean) — Whether to ignore the warning about forbidden module is being spied. Defaults to false.
force (boolean) — Whether to override previously set patches to function. Defaults to false.
mode (:local | :shared | :global) — What mode to use for the patch. See Repatch.mode/0 for more info. Defaults to :local.
expectations_queue (queue/0) — The queue of expectations. It is optional

When no exacly or at_least options are specified, the default behaviour is exactly: 1

expectation()

@type expectation() ::
  {:exactly, pos_integer(), (... -> any())}
  | {:at_least, non_neg_integer(), (... -> any())}

key()

@type key() :: {module(), atom(), arity()}

queue()

@opaque queue()

queues()

@opaque queues()

Functions

cleanup(queues \\ Process.get(:repatch_expectations_queues))

@spec cleanup(queues()) :: boolean()

Performs cleanup of expectations queues. Returns true if queues were found and cleaned up. Returns false if no expectations queues were found

Example

iex> expect(DateTime, :utc_now, fn -> :ok end)
iex> cleanup()
true

expect(queue, func)

@spec expect(queue(), (... -> any())) :: queue()

See expect/4

expect(module, name, func)

@spec expect(module(), atom(), (... -> any())) :: queue()

@spec expect(queue(), [expect_option()], (... -> any())) :: queue()

See expect/4

expect(module, name, opts, func)

@spec expect(module(), atom(), [expect_option()], (... -> any())) :: queue()

Queues up the patch which will be executed once (or multiple times) and then removed from queue. Once all patches are executed, calls to patched function will fail.

See expect_option/0 for all available options.

Example

iex> expect(DateTime, :utc_now, fn -> :first end)
iex> |> expect(fn -> :second end)
iex> |> expect(fn -> :third end)
iex> [DateTime.utc_now(), DateTime.utc_now(), DateTime.utc_now()]
[:first, :second, :third]

Notes

expect/4 supports isolation modes just like Repatch.patch/4 does.
When function called without any expectations empty, it will raise Repatch.Expectations.Empty.
Calling Repatch.patch/4 with force: true will override all expect/2 calls in the current isolation.
To validate the exactly and at_least options, you can use the expectations_empty?/0 function or use Repatch.ExUnit with assert_expectations option.

expectations_empty?(queues \\ Queues.all())

@spec expectations_empty?(queues()) :: boolean()

Checks if there are any expectations empty. Useful in asserts

Example

iex> expect(DateTime, :utc_now, [at_least: 1], fn -> 123 end)
iex> expectations_empty?()
false
iex> DateTime.utc_now()
iex> expectations_empty?()
true

pending_expectations(queues \\ Queues.all())

@spec pending_expectations(queues()) :: [{key(), [expectation()]}]

Lists all not-yet executed expectations

Example

iex> func = fn -> :hello end
iex> expect(DateTime, :utc_now, func)
iex> pending_expectations()
[{{DateTime, :utc_now, 0}, [{:exactly, 1, func}]}]
iex> DateTime.utc_now()
iex> pending_expectations()
[]

Please note that at_least expectations are always returned by the pending_expectations/0