gen-bounds does not work in multiprojects

[newhoggy]

Describe the bug
For multiprojects where one package depends on another inside the project, cabal gen-bounds does not work for projects that have local dependencies.

To Reproduce
Steps to reproduce the behavior:

$ tar zxvf gen-bounds.tar.gz
$ cd gen-bounds
$ cabal build all
$ cd package-b
$ cabal gen-bounds
Warning: The package list for 'hackage.haskell.org' is 15 days old.
Run 'cabal update' to get the latest list of available packages.
Resolving dependencies...
cabal: Could not resolve dependencies:
[__0] trying: package-b-0.1.0.0 (user goal)
[__1] unknown package: package-a (dependency of package-b)
[__1] fail (backjumping, conflict set: package-a, package-b)
After searching the rest of the dependency tree exhaustively, these were the
goals I've had most trouble fulfilling: package-b, package-a

Projects that reference git repositories in cabal.project fail similarly.

Expected behavior
cabal should recognise it is in a multiproject and be able to find local dependencies.

System information

• MacOS (and possibly others)
• cabal-3.4, ghc-8.10.4

Additional context
Attached example code.
gen-bounds.tar.gz

[Mikolaj]

Indeed, the use of ComponentRequestedSpec in genBounds seems suspect.

[ysangkok]

I can't reproduce this with Cabal 3.6.0.0 and GHC 9.0.1. I did get an error regarding the base bounds, but I think that is not relevant to this issue. So I fixed it, and everything built.

[Mikolaj]

Actually, I can't reproduce with cabal-3.4 and ghc-8.10.7 (Linux). What was your OS, @ysangkok?

@newhoggy: any reason this can fail only on MacOS? Case sensitivity? Anything else?

Could anybody else wirh MacOS repro? Best if with cabal 3.4 and cabal 3.6.

[ysangkok]

@Mikolaj I tested on Ubuntu 21.04.

[jneira]

@newhoggy could you confirm if it still is reproduced in your macos with other cabal and ghc versions?

[andreasabel]

This still reproduces with latest cabal (on macOS with GHC 8.10.7). There was a typo in the reproducer (which I edited out just now). The correct reproducer is:

$ cabal build all
$ cd package-b
$ cabal gen-bounds
Error: cabal: Could not resolve dependencies:
[__0] trying: package-b-0.1.0.0 (user goal)
[__1] unknown package: package-a (dependency of package-b)
[__1] fail (backjumping, conflict set: package-a, package-b)

The problem is that local package-a, which package-b depends on, isn't known from the package-b directory as root. It is known from the project root (containing cabal.project), but cabal gen-bounds does not work on projects, only on individual cabal files.

So, the issue is just the same as in the OP.

[zimtsui]

I can reproduce this problem with cabal 3.2, ghc 8.10.4

[Mikolaj]

@zimtsui: thank you. So that doesn't seem like a recent regression, but probably something deeper.

[fendor]

I guess gen-bounds just doesn't use the new-style project orchestration. Ideally, this just about migrating the old code to the new infrastructure.

[nuttycom]

I have a similar/related issue that a cabal.project file referring to a dependency on github prevents gen-bounds from working (though cabal build works fine.)