This page documents how to use Stack on Travis CI. We assume you have basic familiarity with Travis. We provide two fully baked example files ready to be used on your projects:
- The simple Travis configuration
is intended for applications that do not require multiple GHC
support or cross-platform support. It builds and tests your project
with just the settings present in your
- The complex Travis configuration is intended for projects that need to support multiple GHC versions and multiple OSes, such as open source libraries to be released to Hackage. It tests against cabal-install, as well as Stack on Linux and macOS. The configuration is significantly more involved to allow for all of this branching behavior.
NOTE: It is likely going to be necessary to modify this configuration to
match the needs of your project, such as tweaking the build matrix to alter
which GHC versions you test against, or to specify GHC-version-specific
stack.yaml files if necessary. Don't be surprised if it doesn't work the
first time around. See the multiple GHC section below for more information.
Each of these configurations is ready to be used immediately, just
copy-paste the content into the
.travis.yml file in the root or your
repo, enable Travis on the repo, and you're good to go.
You may also be interested in using AppVeyor, which supports Windows builds, for more cross-platform testing. There's a short blog post available on how to do this.
The rest of this document explains the details of common Travis configurations for those of you who want to tweak the above configuration files or write your own.
Note: both Travis and Stack infrastructures are actively developed. We try to document best practices at the moment.
For Stack on Travis to be practical, we must use caching. Otherwise build times will take an incredibly long time, about 30 minutes versus 3-5. Caching is currently available only for container-based Travis infrastructure. Shortly we have to add
sudo: false # Caching so the next build will be fast too. cache: directories: - $HOME/.stack
.travis.yml. This however restricts how we can install GHC and Stack on
the Travis machines.
Currently there is only one reasonable way to install Stack: fetch precompiled binary from the Github.
before_install: # Download and unpack the stack executable - mkdir -p ~/.local/bin - export PATH=$HOME/.local/bin:$PATH - travis_retry curl -L https://www.stackage.org/stack/linux-x86_64 | tar xz --wildcards --strip-components=1 -C ~/.local/bin '*/stack'
There are two ways to install GHC:
- Let Stack download GHC
- Install GHC using apt plugin
See the above scripts for an example of the first option (letting Stack download GHC). Here, we will explain the second option. With single GHC the situation is simple:
before_install: # Install stack as above # ... # Configure stack to use the system GHC installation - stack config set system-ghc --global true - export PATH=/opt/ghc/7.10.2/bin:$PATH addons: apt: sources: - hvr-ghc packages: - ghc-7.10.2
Multiple GHC - parametrised builds¶
Travis apt plugin doesn't yet support installing apt packages dynamically
(https://github.com/travis-ci/travis-ci/issues/4291). That for we need to write
a bit repetitive
Also for different GHC versions, you probably want to use different
# N.B. No top-level env: declaration! matrix: include: - env: GHCVER=7.8.4 STACK_YAML=stack.yaml addons: apt: sources: - hvr-ghc packages: - ghc-7.8.4 - env: GHCVER=7.10.1 STACK_YAML=stack-7.10.yaml addons: apt: sources: - hvr-ghc packages: - ghc-7.10.1 - env: GHCVER=head STACK_YAML=stack-head.yaml addons: apt: sources: - hvr-ghc packages: - ghc-head allow_failures: - env: GHCVER=head STACK_YAML=stack-head.yaml before_install: # ghc - export PATH=/opt/ghc/$GHCVER/bin:$PATH
Especially to use ghc
HEAD you need to pass
--skip-ghc-check option to Stack.
After the environment setup, actual test running is simple:
script: - stack --no-terminal --skip-ghc-check test
In case you're wondering: we need
--no-terminal because stack does some fancy
sticky display on smart terminals to give nicer status and progress messages,
and the terminal detection is broken on Travis.
Some Stack commands will run for long time (when cache is cold) without producing any output. To avoid timeouts, use the built in travis_wait.
install: - travis_wait stack --no-terminal --skip-ghc-check setup - travis_wait stack --no-terminal --skip-ghc-check test --only-snapshot
Once Travis whitelists the stack .deb files, we'll be able to simply include
stack in the
addons section, and automatically use the newest version of
stack, avoiding that complicated
before_install section This is being
tracked in the