jonathanknowles / haskell-example Goto Github PK

Thanks for publishing this action! Here a comment on cache keys:

Since cabal.project.freeze will contain the Hackage repository timestamp, it will be different in almost every single CI run. Thus, it might not be a suitable cache key, being similar to ${{ github.sha }}.

I settled for dist-newstyle/cache/plan.json instead which only contains the package versions, no time stamps. It is generated by cabal build --dry-run.

See e.g. https://github.com/agda/agda/blob/e018e58453a06e4c4a15c9b81396cbcd1e2c640f/src/github/workflows/cabal.yml#L148-L171

There might be reasons why you want the primary key being different in each run, but then it is easier to just use ${{ github.sha }}.

Task

Remove the following "purge" step from the build workflow:

Dependencies

This task can only be performed after actions/runner-images#6972 has been merged.

Context

The "purge" step was introduced to work around issues caused by incomplete installations of GHC on certain GitHub runner images, where documentation for GHC core libraries (such as base) is completely missing:

haskell/actions#176

The root cause is a section of code that deletes documentation for all GHC core libraries:

https://github.com/actions/runner-images/blob/c6393f1f231a4bce8aaeb2665d1312b14271169b/images/linux/scripts/installers/haskell.sh#L34-L39

The lack of documentation for GHC core libraries makes it impossible to build haddock documentation with working hyperlinks to those core libraries.