Fl4m3Ph03n1x
Background
I have an umbrella project with several apps.
Some of these apps have runtime libraries as dependencies, some apps depend on others and so on.
My objective is, when on the root level of the project, to run all the tests for all the child apps using mix test.
Problem
When on the root level, running mix test will run the tests of all child apps. However this happens in a parallel way, from what I can see.
This is a problem because some dependencies between child apps are shared. Consequently some apps succeed, and others fail, thus breaking my CI/CD pipeline.
This is not a problem at all if I run the tests for each child separately, but alas, I want to be able to use mix test from the root level.
What I tried
So, my initial approach was create an alias that replaces mix test with my own command:
defp aliases do
[
test: ["cmd --app app1 mix test --color", "cmd --app app2 mix test --color"]
]
end
This will work and will execute the tests of the child apps sequentially.
Questions
However this solution is hard-coded and not very flexible. If tomorrow I remove an app, the command will break. If I add a new one, the command won’t run its tests unless I remember to edit it.
I wonder if there is a better way of doing this that would be:
- flexible instead of hard-coded
- run the tests sequentially instead of parallel
Where Next?
Trending in Questions
Other Trending Topics
Latest on Elixir Forum
Sponsor Spotlight
Error tracking, logs, APM, uptime and cron monitoring in one dev-friendly platform. Find and fix problems before your users notice.
Categories:
Sub Categories:
Forums
Popular Tags
- #ecto
- #liveview
- #troubleshooting
- #learning-elixir
- #library
- #deployment
- #erlang
- #testing
- #genserver
- #mix
- #absinthe
- #remote-other
- #otp
- #plug
- #how-to-question
- #macros
- #postgres
- #elixirconf
- #channels
- #exunit
- #discussion
- #code-sync
- #podcasts
- #javascript
- #onsite
- #dialyzer
- #docker
- #authentication
- #umbrella
- #full-time-contract
- #podcasts-by-brainlid
- #ecto-query
- #ai
- #elixirconf-us
- #blog-post
- #elixir-ls
- #phoenix_html
- #iex
- #graphql
- #genstage
- #websockets
- #supervisor
- #advent-of-code
- #distillery
- #processes
- #api
- #forms
- #elixirconf-eu
- #metaprogramming
- #hex
Our Sponsors
Build Elixir applications with speed and confidence.
We build reliable cloud platforms for business-critical systems.
Catch errors, track performance, monitor hosts and more.
Error tracking, logs, uptime, and Just Enough APM. Built for developers.
Elixir, Erlang & BEAM conferences from Code Sync - join us in 2026!
Practical resources that improve the lives of professional developers.
Producing high quality Elixir screencasts since 2017.
**Building the future of software with AI, trust, and human connection.**
The team behind Membrane, Popcorn, LiveDebugger. Available for hire.
Courses that'll move you from confusion to "Aha, now I get it!"
Showing Posts 1 to 4- Show Best Posts
- Show All (oldest first)
- Show All (newest first)
LostKobrakai
So the proper solution would be removing any global state from your testsuites, which makes
mix testfail as it does.But also mix.exs is elixir – you can use code to define the alias:
Fl4m3Ph03n1x
Unfortunately this won’t work, as
Mix.Project.app_paths()is not resolved at compile time. So when I run the command, line 2 gets anilinstead of a keyword list and the whole thing crashes.I have also tried
Mix.Project.config(), which does work at compile time, but sadly it has no information about child apps.LostKobrakai
Path.wildcard("apps/*)would likely do fine as wellFl4m3Ph03n1x
This did the trick. Thanks