Kristen Kozak

Issue #7270 shows that there is actually more to do here than enforcing visibility. The hack described above means that the solver handles sublibraries differently depending on whether they are...

Thanks @Mikolaj! Here are some more details about my question. Cabal passes the installed package index to the dependency solver using the type InstalledPackageIndex, as used in this function that...

We discussed the issue with grouping installed libraries by package instance at the Cabal meeting. It sounds like the information that we would need is probably not available within cabal,...

@Mikolaj The next step is to determine how cabal-install handles multiple installed instances of a package (especially packages with multiple libraries) to answer @fgaz's questions in https://github.com/haskell/cabal/issues/6039#issuecomment-1092642955. If cabal-install does...

https://github.com/haskell/cabal/issues/3085#issuecomment-175986358 and #4852 are related.

> By the way, what does the list in Distribution.Solver.Modular.Solver do now? That list seems redundant with the list in Distribution.Client.Dependency. It looks like cabal avoids choosing a source version...

> I would love to add tests to check if those packages are correctly marked as non-upgradable, but I do not know how. I would like to know how to...

> Should I create test case for each of "ghc", "ghci", and "ghc-boot"? Sure, that sounds fine. > What error message should I check? It looks like the error will...

@Abastro I think it would be better to only check that the error message contains "rejecting: ghc-2.0.0 (constraint from non-upgradeable package requires installed instance)", because that ensures that the correct...

@Abastro Can I apply the "squash+merge me" label, since this PR looks ready to merge, and the commits look like they should be combined?