Stack build fails for "Hello World" executable project with error: ghc-pkg: cannot find package

[VictorTaelin]

Stack is failing to build a "Hello World" executable here. Here is the log:

$ mkdir Aff

$ cd Aff

$ echo "main = print \"hello world\"" >> Main.hs

$ cabal init

Package name? [default: Aff]
Package version? [default: 0.1.0.0]
Please choose a license:
* 1) (none)
2) GPL-2
3) GPL-3
4) LGPL-2.1
5) LGPL-3
6) AGPL-3
7) BSD2
8) BSD3
9) MIT
10) ISC
11) MPL-2.0
12) Apache-2.0
13) PublicDomain
14) AllRightsReserved
15) Other (specify)
Your choice? [default: (none)]
Author name? [default: V]
Maintainer email? [default: v]
Project homepage URL?
Project synopsis?
Project category:
* 1) (none)
2) Codec
3) Concurrency
4) Control
5) Data
6) Database
7) Development
8) Distribution
9) Game
10) Graphics
11) Language
12) Math
13) Network
14) Sound
15) System
16) Testing
17) Text
18) Web
19) Other (specify)
Your choice? [default: (none)]
What does the package build:
1) Library
2) Executable
Your choice? 2
What is the main module of the executable:
* 1) Main.hs
2) Other (specify)
Your choice? [default: Main.hs]
What base language is the package written in:
* 1) Haskell2010
2) Haskell98
3) Other (specify)
Your choice? [default: Haskell2010]
Include documentation on what each field means (y/n)? [default: n]
Source directory:
* 1) (none)
2) src
3) Other (specify)
Your choice? [default: (none)]

Guessing dependencies...

Generating LICENSE...
Warning: unknown license type, you must put a copy in LICENSE yourself.
Generating Setup.hs...
Generating Aff.cabal...

Warning: no synopsis given. You should edit the .cabal file and add one.
You may want to edit the .cabal file and add a Description field.

$ stack init

Writing default config file to: /Users/v/Aff/stack.yaml
Basing on cabal files:
- /Users/v/Aff/Aff.cabal

Checking against build plan lts-3.7
Selected resolver: lts-3.7
Wrote project config to: /Users/v/Aff/stack.yaml

$ echo "AFF" >> LICENSE

$ stack build

Aff-0.1.0.0: build
Preprocessing executable 'Aff' for Aff-0.1.0.0...
Aff-0.1.0.0: copy/register
Installing executable(s) in
/Users/v/Aff/.stack-work/install/x86_64-osx/lts-3.7/7.10.2/bin
Package contains no library to register: Aff-0.1.0.0...
Running /Applications/ghc-7.10.2.app/Contents/bin/ghc-pkg --user --no-user-package-db --package-db /Users/v/Aff/.stack-work/install/x86_64-osx/lts-3.7/7.10.2/pkgdb/ describe --simple-output Aff --expand-pkgroot exited with ExitFailure 1

ghc-pkg: cannot find package Aff

Moreover, it is failing to build a project that was building fine until yesterday, and nothing changed on it. The project is available at http://github.com/maiavictor/haelin. The error is similar: ghc-pkg: cannot find package Test (which is the only executable inside my project). The only thing I did was update stack to enable GHCJS, as suggested on the GHCJS thread:

stack upgrade --git

This is the version I have:

Vs-MacBook:~ v$ stack --version
Version 0.1.7.0, Git revision 33462aba13f85a3d5c1690c6ee0bb3dd4af6b616 x86_64

I'm under OSX El Capitain.

[snoyberg]

I think I know what's happening...

[snoyberg]

Out of curiosity: what's your stack exec -- ghc-pkg list Cabal output look like?

My guess is that this broke due to my change to use the register command to Cabal (due to a Cabal bug around post install hooks). I'm unable to reproduce this issue myself, but perhaps there's an OS or Cabal version issue at play. In any event, saying "only register if there's a library" is simple enough.

[snoyberg]

@MaiaVictor I believe this should now be fixed on master. After pulling the latest master, I was also able to reproduce this problem, and it was unrelated to the code change I thought it might be part of.

Can you confirm that after stack upgrade --git this works?

[VictorTaelin]

@snoyberg I am really sorry for the delay! I've left stack upgrading and will tell you whether it works as soon as I get back from work. The output of stack exec -- ghc-pkg list Cabal looks like:

Run from outside a project, using implicit global project config
Using resolver: lts-3.7 from implicit global project's config file: /Users/v/.stack/global/stack.yaml
/Applications/ghc-7.10.2.app/Contents/lib/ghc-7.10.2/package.conf.d
Cabal-1.22.4.0
/Users/v/.stack/snapshots/x86_64-osx/lts-3.7/7.10.2/pkgdb
/Users/v/.stack/global/.stack-work/install/x86_64-osx/lts-3.7/7.10.2/pkgdb

[VictorTaelin]

Okay, turns out it updated quite quickly so I was able to test it already. Seems like everything works. Thank you!

[snoyberg]

No problem