mix test.interactive

mix test.interactive is an interactive test runner for ExUnit tests.

Based on Louis Pilfold's wonderful mix-test.watch and inspired by Jest's interactive watch mode, mix test.interactive allows you to dynamically change which tests should be run with a few keystrokes.

It allows you to easily switch between running all tests, stale tests, or failed tests. Or, you can run only the tests whose filenames contain a substring. Includes an optional "watch mode" which runs tests after every file change.

Installation

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

def deps do
  [
    {:mix_test_interactive, "~> 1.0", only: :dev, runtime: false}
  ]
end

Usage

Run the mix task:

mix test.interactive

Your tests will run immediately (and every time a file changes).

If you don't want tests to run automatically when files change, you can start mix test.interactive with the --no-watch flag:

mix test.interactive --no-watch

After the tests run, you can use the interactive mode to change which tests will run.

Use the p command to run only test files that match one or more provided patterns. A pattern is the project-root-relative path to a test file (with or without a line number specification) or a string that matches a portion of full pathname. e.g. test/my_project/my_test.exs, test/my_project/my_test.exs:12:24 or my.

If any pattern contains a line number specification, all patterns are passed directly to mix test.

p pattern1 pattern 2

Use the s command to run only test files that reference modules that have changed since the last run (equivalent to the --stale option of mix test).

Use the f command to run only tests that failed on the last run (equivalent to the --failed option of mix test).

Use the a command to run all tests.

Use the w command to turn file-watching mode on or off.

Use the Enter key to re-run the current set of tests without requiring a file change.

Use the q command, or press Ctrl-D to exit the program.

Running A Different Mix Task

By default, mix test.interactive runs mix test. Through the mix config it is possible to run a different mix task. mix test.interactive assumes that this alternative task accepts the same command-line arguments as mix test.

# config/config.exs
use Mix.Config

if Mix.env == :dev do
  config :mix_test_interactive,
    task: "custom_test_task"
end

The task is run with MIX_ENV set to test.

Passing Arguments To Tasks

Any command line arguments passed to the mix test.interactive task will be passed through to the task being run, along with any arguments added by interactive mode. If I want to see detailed trace information for my tests, I can run:

mix test.interactive --trace

mix test.interactive will detect the --stale and --failed flags and use those as initial settings in interactive mode. You can then toggle those flags on and off as needed. It will also detect any filename or pattern arguments and use those as initial settings. However, it does not detect any filenames passed with --include or --only. Note that if you specify a pattern on the command-line, mix test.interactive will find all test files matching that pattern and pass those to mix test as if you had used the p command.

Clearing The Console Before Each Run

If you want mix test.interactive to clear the console before each run, you can enable this option in your config/dev.exs as follows:

# config/config.exs
use Mix.Config

if Mix.env == :dev do
  config :mix_test_interactive,
    clear: true
end

Excluding files or directories

To ignore changes from specific files or directories add exclude: regexp patterns to your config in mix.exs:

# config/config.exs
use Mix.Config

if Mix.env == :dev do
  config :mix_test_interactive,
    exclude: [~r/db_migration\/.*/,
              ~r/useless_.*\.exs/]
end

The default is exclude: [~r/\.#/, ~r{priv/repo/migrations}].

Compatibility Notes

On Linux you may need to install inotify-tools.

Desktop Notifications

You can enable desktop notifications with ex_unit_notifier.

Acknowledgements

This project started as a clone of the wonderful mix-test.watch project, which I've used and loved for years. I've added the interactive mode features to the existing feature set.

The idea for having an interactive mode comes from Jest and its incredibly useful interactive watch mode.

Copyright and License

Copyright (c) 2021-2022 Randy Coulman

This work is free. You can redistribute it and/or modify it under the terms of the MIT License. See the LICENSE.md file for more details.