mockth

Gleam modules mocking library. This is a simple wrapper around Erlang Meck library.

gleam add mockth

Usage

It provides a simple API to mock Gleam modules and functions. All you need to use mockth.expect function to mock any external function with your own implementation.

import gleeunit
import gleeunit/should
import gleam/function
import mockth

pub fn main() {
  gleeunit.main()
}

pub fn expect1_test() {
  let assert Ok(_) =
    mockth.expect1("gleam@function", "identity", fn(_) { "hello" })

  mockth.validate("gleam@function")
  |> should.equal(True)

  mockth.mocked()
  |> should.equal(["gleam@function"])

  function.identity("world")
  |> should.equal("hello")

  mockth.unload_all()
}

Don't forget to unload all mocks after each test case.

Further documentation can be found at https://hexdocs.pm/mockth.

Development

gleam run   # Run the project
gleam test  # Run the tests
gleam shell # Run an Erlang shell