# mix test.interactive
[](https://app.circleci.com/pipelines/github/influxdata/mix_test_interactive)
[](https://hex.pm/packages/mix_test_interactive)
`mix test.interactive` is an interactive test runner for ExUnit tests.
Based on Louis Pilfold's wonderful [mix-test.watch](https://github.com/lpil/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`:
```elixir
def deps do
[
{:mix_test_interactive, "~> 1.0", only: :dev, runtime: false}
]
end
```
## Usage
Run the mix task:
```shell
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:
```shell
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`.
```elixir
# 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:
```elixir
# 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`:
```elixir
# 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](https://github.com/navinpeiris/ex_unit_notifier).
## Acknowledgements
This project started as a clone of the wonderful [mix-test.watch](https://github.com/lpil/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](https://jestjs.io/) and its incredibly useful interactive watch mode.
