offline flag disables source-repository-package sync

[peterbecich]

Closes: #9641

How this was tested:

• use the example project: https://github.com/peterbecich/cabal2nix-project-issue
  • this example pulls the text library as a source-repository-package
• build, install Cabal from this PR
  • cabal install cabal --overwrite-policy=always
• in the example project, delete dist-newstyle to remove the text library cached there
  • rm -rf dist-newstyle; ~/.cabal/bin/cabal build
  • text library pulled, build succeeds
• next, build with the cached text library and offline flag
  • ~/.cabal/bin/cabal build --offline
  • this succeeds
  • offline flag does not break the cached library
• next, delete dist-newstyle again, and attempt build with --offline
  • rm -rf dist-newstyle; ~/.cabal/bin/cabal build --offline
  • this fails, as intended
  • this proves the offline flag is preventing the text library from being pulled
  • the error message could be improved:

$ rm -rf dist-newstyle; ~/.cabal/bin/cabal build --offline
.../dist-newstyle/src/text-8e814f5854032da8: getDirectoryContents:openDirStream:
  does not exist (No such file or directory)

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[geekosaur]

I do wonder if this should print something (not sure if level info or warning) when skipping due to being offline.

[peterbecich]

I have implemented a warning. However, it is still followed by a cryptic error message:

$ rm -rf dist-newstyle; ~/.cabal/bin/cabal build --offline
Warning: --offline was specified, skipping sync of repositories:
Warning: https://github.com/haskell/text.git
.../dist-newstyle/src/text-8e814f5854032da8: getDirectoryContents:openDirStream: does not exist (No such file or directory)

If the dependency is cached, there is only a warning

$ ~/.cabal/bin/cabal build --offline
Warning: --offline was specified, skipping sync of repositories:
Warning: https://github.com/haskell/text.git
Warning: no repository provided none
Resolving dependencies...

[peterbecich]

@geekosaur , can this be merged? Thanks

[geekosaur]

It needs another reviewer; I've attached the needs-review label, which hopefully will get some more eyes on it.

[peterbecich]

Thank you

[geekosaur]

I'll add the "merge me" label for you per the PR guidelines. There will then be a 2 day cooldown period to let others comment on the PR before Mergify merges it.

[Kleidukos]

@Mergifyio backport 3.12

[mergify]

backport 3.12

✅ Backports have been created

• #10021 offline flag disables source-repository-package sync (backport #9771) has been created for branch 3.12