Why is stringi required for travis-ci?


Recently our Travis pipeline failed due to an upstream error in stringi:


It seems caused by this issue:

We attempted to fix this here but the error still shows up, I believe because Travis itself is using stringi:

Can anyone help to clarify why stringi is required for Travis CI builds?

From https://travis-ci.org/Rdatatable/data.table/builds/635082210#L1026 and https://travis-ci.org/Rdatatable/data.table/builds/635082210#L1026, it looks like stringi and/or whatever requires it is present in your build cache (~/R/Library is always cached to save on build times unless you explicitly disable that). So you need to clean the appropriate cache(s).

Still, the command that installs (updates) stringi in the affected build
is remotes::install_deps(dependencies=TRUE) which means that it’s something in your project that requires stringi, perhaps transitively.