cabal new-haddock regression (setup: internal error when calculating transitive package dependencies.)

[RyanGlScott]

I originally noticed this issue when trying to upgrade singletons' Travis setup to use cabal-install-head. That is:

$ /opt/cabal/head/bin/cabal --version
cabal-install version 2.3.0.0
compiled using version 2.3.0.0 of the Cabal library

I've prepared a more minimal reproduction at https://github.com/RyanGlScott/cabal-gh5423. To reproduce the issue, do the following:

$ git clone https://github.com/RyanGlScott/cabal-gh5423
$ cd cabal-gh5423/
$ /opt/cabal/head/bin/cabal new-haddock cabal-gh5423:tests
Resolving dependencies...
Build profile: -w ghc-8.4.3 -O1
In order, the following will be built (use -v for more details):
 - cabal-gh5423-0.1 (first run)
[1 of 1] Compiling Main             ( /home/rgscott/Documents/Hacking/Haskell/cabal-gh5423/dist-newstyle/build/x86_64-linux/ghc-8.4.3/cabal-gh5423-0.1/setup/setup.hs, /home/rgscott/Documents/Hacking/Haskell/cabal-gh5423/dist-newstyle/build/x86_64-linux/ghc-8.4.3/cabal-gh5423-0.1/setup/Main.o )
Linking /home/rgscott/Documents/Hacking/Haskell/cabal-gh5423/dist-newstyle/build/x86_64-linux/ghc-8.4.3/cabal-gh5423-0.1/setup/setup ...
Configuring cabal-gh5423-0.1...
Found dependency closure
Preprocessing library for cabal-gh5423-0.1..
Running Haddock on library for cabal-gh5423-0.1..
Haddock coverage:
   0% (  0 /  1) in 'CabalSandbox'
  Missing documentation for:
    Module header
Documentation created:
/home/rgscott/Documents/Hacking/Haskell/cabal-gh5423/dist-newstyle/build/x86_64-linux/ghc-8.4.3/cabal-gh5423-0.1/doc/html/cabal-gh5423/index.html
Preprocessing test suite 'cabal-gh5423-tests' for cabal-gh5423-0.1..
Running Haddock on test suite 'cabal-gh5423-tests' for cabal-gh5423-0.1..
setup: internal error when calculating transitive package dependencies.
Debug info: []

cabal: Failed to build documentation for cabal-gh5423-0.1.

cabal-gh5423 is a package with a library, test suite, and custom-setup script that looks like:

module Main (main) where

import Distribution.PackageDescription
import Distribution.Simple
import Distribution.Simple.LocalBuildInfo
import Distribution.Simple.PackageIndex

main :: IO ()
main = defaultMainWithHooks simpleUserHooks
  { haddockHook = \pkg lbi hooks flags -> do
      blah pkg lbi
      haddockHook simpleUserHooks pkg lbi hooks flags
  }

blah :: PackageDescription -> LocalBuildInfo -> IO ()
blah pkg lbi =
  withLibLBI pkg lbi $ \_ libCLBI -> do
    let libDeps = map fst $ componentPackageDeps libCLBI
    case dependencyClosure (installedPkgs lbi) libDeps of
      Left p  -> p `seq` putStrLn "Found dependency closure"
      Right _ -> error "Broken dependency closure"

(In reality, singletons actually uses the computed dependency closure for something useful, but I've elided this for the sake of keeping things simple.)

[RyanGlScott]

For comparison, it succeeds with cabal-install-2.2:

$ /opt/cabal/2.2/bin/cabal new-haddock cabal-gh5423:tests
Resolving dependencies...
Build profile: -w ghc-8.4.3 -O1
In order, the following will be built (use -v for more details):
 - cabal-gh5423-0.1 (first run)
[1 of 1] Compiling Main             ( /home/rgscott/Documents/Hacking/Haskell/cabal-gh5423/dist-newstyle/build/x86_64-linux/ghc-8.4.3/cabal-gh5423-0.1/setup/setup.hs, /home/rgscott/Documents/Hacking/Haskell/cabal-gh5423/dist-newstyle/build/x86_64-linux/ghc-8.4.3/cabal-gh5423-0.1/setup/Main.o )
Linking /home/rgscott/Documents/Hacking/Haskell/cabal-gh5423/dist-newstyle/build/x86_64-linux/ghc-8.4.3/cabal-gh5423-0.1/setup/setup ...
Configuring cabal-gh5423-0.1...
Found dependency closure
Preprocessing library for cabal-gh5423-0.1..
Running Haddock on library for cabal-gh5423-0.1..
Haddock coverage:
   0% (  0 /  1) in 'CabalSandbox'
  Missing documentation for:
    Module header
Documentation created:
/home/rgscott/Documents/Hacking/Haskell/cabal-gh5423/dist-newstyle/build/x86_64-linux/ghc-8.4.3/cabal-gh5423-0.1/doc/html/cabal-gh5423/index.html
Preprocessing test suite 'cabal-gh5423-tests' for cabal-gh5423-0.1..

[RyanGlScott]

I cannot appear to reproduce this on cabal-install-2.4.0.0/Cabal-2.4.0.1, so perhaps this is no longer an issue?

[hvr]

maybe this was fixed as a side-effect of #5253

[23Skidoo]

Optimistically closing, please reopen if the issue resurfaces.

[RyanGlScott]

Actually, this is still an issue, but it requires particular circumstances to trigger it. In particular, you need:

• The cabal v2-haddock all --haddock-all command,
• A custom Setup.hs script that calls dependencyClosure, and
• A version of cabal-install that links against a different major version of Cabal than what is bundled with the GHC version that you are using.

Here is a demonstration of the bug using modern versions of cabal-install and GHC. I can trigger the bug with:

• GHC 9.4.1 (which bundles Cabal-3.8.1.0) and cabal-install-3.6.2.0 (which links against Cabal-3.6.2.0):

  $ cabal-3.6.2.0.exe v2-haddock all --haddock-all -w ghc-9.4.1
  Warning: Unknown/unsupported 'ghc' version detected (Cabal 3.6.2.0 supports
  'ghc' version < 9.4): C:\ghcup\bin\ghc-9.4.1.exe is version 9.4.1
  Resolving dependencies...
  Build profile: -w ghc-9.4.1 -O1
  In order, the following will be built (use -v for more details):
   - cabal-gh5423-0.1 (first run)
  [1 of 2] Compiling Main             ( C:\\Users\winferno\Documents\Hacking\Haskell\cabal-gh5423\dist-newstyle\build\x86_64-windows\ghc-9.4.1\cabal-gh5423-0.1\setup\setup.hs, C:\\Users\winferno\Documents\Hacking\Haskell\cabal-gh5423\dist-newstyle\build\x86_64-windows\ghc-9.4.1\cabal-gh5423-0.1\setup\Main.o )
  [2 of 2] Linking C:\\Users\\winferno\\Documents\\Hacking\\Haskell\\cabal-gh5423\\dist-newstyle\\build\\x86_64-windows\\ghc-9.4.1\\cabal-gh5423-0.1\\setup\\setup.exe
  Configuring cabal-gh5423-0.1...
  Found dependency closure
  Preprocessing library for cabal-gh5423-0.1..
  Running Haddock on library for cabal-gh5423-0.1..
  Warning: The documentation for the following packages are not installed. No
  links will be generated to these packages: base-4.17.0.0, ghc-bignum-1.3,
  ghc-prim-0.9.0
     0% (  0 /  1) in 'CabalSandbox'
    Missing documentation for:
      Module header
  Documentation created:
  C:\Users\winferno\Documents\Hacking\Haskell\cabal-gh5423\dist-newstyle\build\x86_64-windows\ghc-9.4.1\cabal-gh5423-0.1\doc\html\cabal-gh5423\index.html
  Preprocessing test suite 'cabal-gh5423-tests' for cabal-gh5423-0.1..
  Running Haddock on test suite 'cabal-gh5423-tests' for cabal-gh5423-0.1..
  setup.exe: internal error when calculating transitive package dependencies.
  Debug info: []
  
  cabal-3.6.2.0.exe: Failed to build documentation for cabal-gh5423-0.1.
  

• GHC 9.2.4 (which bundles Cabal-3.6.3.0) and cabal-install-3.8.1.0 (which links against Cabal-3.8.1.0):

  $ cabal-3.8.1.0.exe v2-haddock all --haddock-all -w ghc-9.2.4
  Resolving dependencies...
  Build profile: -w ghc-9.2.4 -O1
  In order, the following will be built (use -v for more details):
   - cabal-gh5423-0.1 (first run)
  [1 of 1] Compiling Main             ( C:\\Users\winferno\Documents\Hacking\Haskell\cabal-gh5423\dist-newstyle\build\x86_64-windows\ghc-9.2.4\cabal-gh5423-0.1\setup\setup.hs, C:\\Users\winferno\Documents\Hacking\Haskell\cabal-gh5423\dist-newstyle\build\x86_64-windows\ghc-9.2.4\cabal-gh5423-0.1\setup\Main.o )
  Linking C:\\Users\\winferno\\Documents\\Hacking\\Haskell\\cabal-gh5423\\dist-newstyle\\build\\x86_64-windows\\ghc-9.2.4\\cabal-gh5423-0.1\\setup\\setup.exe ...
  Configuring cabal-gh5423-0.1...
  Found dependency closure
  Preprocessing library for cabal-gh5423-0.1..
  Running Haddock on library for cabal-gh5423-0.1..
  Warning: The documentation for the following packages are not installed. No
  links will be generated to these packages: base-4.16.3.0, ghc-bignum-1.2,
  ghc-prim-0.8.0
     0% (  0 /  1) in 'CabalSandbox'
    Missing documentation for:
      Module header
  Documentation created:
  C:\Users\winferno\Documents\Hacking\Haskell\cabal-gh5423\dist-newstyle\build\x86_64-windows\ghc-9.2.4\cabal-gh5423-0.1\doc\html\cabal-gh5423\index.html
  Preprocessing test suite 'cabal-gh5423-tests' for cabal-gh5423-0.1..
  Running Haddock on test suite 'cabal-gh5423-tests' for cabal-gh5423-0.1..
  setup.exe: internal error when calculating transitive package dependencies.
  Debug info: []
  
  Error: cabal-3.8.1.0.exe: Failed to build documentation for cabal-gh5423-0.1.
  

However, note that the bug does not occur if I use:

• GHC 9.4.1 (which bundles Cabal-3.8.1.0) and cabal-install-3.8.1.0 (which links against Cabal-3.8.1.0)
• GHC 9.2.4 (which bundles Cabal-3.6.3.0) and cabal-install-3.6.2.0 (which links against Cabal-3.6.2.0)

This is likely why I didn't notice the bug in #5423 (comment), as I switched from using cabal-install-2.3.0.0 to cabal-install-2.4.0.0, the latter of links against the same major version of Cabal (2.4.0.1) as the version of Cabal that GHC 8.4.3 bundles.

[RyanGlScott]

This issue is, unfortunately, preventing me from building singletons-base on CI at the moment. singletons-base uses a custom Setup.hs script involving dependencyClosure, and if I try to combine GHC 9.4.1 with cabal-install-3.6.2.0, then things break as above when building the Haddocks using v2-haddock all --haddock-all.

The closest existing issue that I can find to this is #1919, which has been fixed upstream (see #7827). It's not clear to me if I need to update the custom Setup.hs script somehow in order to avoid #1919. (In fact, another custom Setup.hs script user was wondering the same thing.)

[Mikolaj]

It's not clear to me if I need to update the custom Setup.hs script somehow in order to avoid #1919.

I don't remember (assuming I understood it at the time). However, the fix is not present in cabal 3.6, but only in 3.8, so certainly using cabal 3.8 is required (which matches your test results?).

[RyanGlScott]

However, the fix is not present in cabal 3.6, but only in 3.8

I'm not sure it's that simple. As noted in #5423 (comment), the bug doesn't surface if I use cabal-3.6.2.0 + GHC 9.2.4.

[Mikolaj]

Yes, we won't know until GHC 9.6 is released.

[ysangkok]

@Mikolaj What will we not know until GHC 9.6 is released?

This is reproducible with cabal-install-3.10.1.0 and GHC 9.2.7:

janus@gorm ~/flipstone/cabal-gh5423
 % cabal haddock --haddock-tests -w ghc-9.2.7 
Build profile: -w ghc-9.2.7 -O1
In order, the following will be built (use -v for more details):
 - cabal-gh5423-0.1 (first run)
Found dependency closure
Preprocessing library for cabal-gh5423-0.1..
Running Haddock on library for cabal-gh5423-0.1..
   0% (  0 /  1) in 'CabalSandbox'
  Missing documentation for:
    Module header
Documentation created:
/home/janus/flipstone/cabal-gh5423/dist-newstyle/build/x86_64-linux/ghc-9.2.7/cabal-gh5423-0.1/doc/html/cabal-gh5423/index.html
Preprocessing test suite 'cabal-gh5423-tests' for cabal-gh5423-0.1..
Running Haddock on test suite 'cabal-gh5423-tests' for cabal-gh5423-0.1..
setup: internal error when calculating transitive package dependencies.
Debug info: []

Error: cabal: Failed to build documentation for cabal-gh5423-0.1.

janus@gorm ~/flipstone/cabal-gh5423
 % cabal --version
cabal-install version 3.10.1.0
compiled using version 3.10.1.0 of the Cabal library

[Mikolaj]

@Mikolaj What will we not know until GHC 9.6 is released?

I have no idea!

However, given that fixes in many tools were needed, perhaps the best we can do is ensure newest versions of all tools do not exhibit the behaviour. Whether that includes the newest version of GHC, I'm not sure. But perhaps the usage of ghc-9.2.7 implies the usage of an older haddock? Or bounds on base somewhere imply that older package are used? I guess, it might be useful to try to run the interesting examples with the haddock that comes with GHC 9.6 and also with --allow-newer to make sure base bounds don't interfere. Then we might conclude, e.g., that new cabal and new haddock are enough and GHC version only matters in that it should be compatible with new cabal and haddock.

[ysangkok]

with GHC 9.6 and also with --allow-newer

The allow-newer doesn't seem to change anything, because the internal error is still avoided:

% cabal-3.10.1.0 haddock --haddock-tests -w ghc-9.6.1 --allow-newer 
[...]
tests/Tests.hs:3:1: error:
    Could not find module ‘CabalSandbox’
    There are files missing in the ‘cabal-gh5423-0.1’ package,
    try running 'ghc-pkg check'.
    Use -v (or `:set -v` in ghci) to see a list of the files searched for.
  |
3 | import CabalSandbox ()
  | ^^^^^^^^^^^^^^^^^^^^^^

I am not sure whether the CabalSandbox error is expected or not, do you know @RyanGlScott ?

Also, Ryan, you wrote

the bug doesn't surface if I use cabal-3.6.2.0 + GHC 9.2.4.

I am able to reproduce an internal error with this combination, am I doing something wrong?

 % cabal-3.6.2.0 haddock --haddock-tests -w ghc-9.2.4
[...]
setup: internal error when calculating transitive package dependencies.

Same with 9.2.7.

[RyanGlScott]

I am not sure whether the CabalSandbox error is expected or not, do you know @RyanGlScott ?

No, that is definitely not expected. A normal cabal test invocation compiles without issues, so the fact that cabal haddock --haddock-tests does not compile smells like a bug.

I am able to reproduce an internal error with this combination, am I doing something wrong?

Now that you mention it, I am also able to reproduce this. Unfortunately, enough time has passed since I wrote my original comment in #5423 (comment) that I don't know if this was a mistake on my part or if something else changed in the interim...