[MacPorts] #62228: haskell-stack 1.0: set stack root to home directory

[MacPorts]

#62228: haskell-stack 1.0: set stack root to home directory
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  Reporter:  Ionic   |      Owner:  (none)
      Type:  defect  |     Status:  new
  Priority:  Normal  |  Milestone:
 Component:  ports   |    Version:
Resolution:          |   Keywords:
      Port:          |
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Comment (by Ionic):

 Replying to [comment:1 neverpanic]:
 > Sounds reasonable to me.

 I still cannot quite explain what is happening there, though. I've been
 trying to reproduce this with a minimal test case to report this as a bug
 to upstream, but so far haven't finished/managed.

 It's almost certainly a combination of using a build user and then running
 destroot as root. The weird part is that we are supplying `--allow-
 different-user`, which should enable sharing. `${workpath}/.stack` is
 created as the `macports` user, so it does (initially) have write
 permissions there.

 The weirdest part is that it's ignoring `STACK_ROOT=${workpath}.stack`
 when running as **root** in the destroot phase (and falling back to
 `${HOME}/.stack`, a.k.a. `${workpath}/.home/.stack` instead), which...
 just doesn't make sense to me.

 You've put me on the right track, though, I think, since most files in
 `${workpath}/.stack` seem to be owned by root instead of macports. They
 also are newer than the ones in `${workpath}/.home/.stack`, which are
 owned by macports only, so maybe I just confused the two directories.

 > I'm surprised to find stack use `~/.stack`, though, since we're running
 things as `macports` user, so it should be using `~macports/.stack`, where
 it cannot write. I'm guessing that happens because destroot runs as root.

 I didn't really mean `~loggedinuser/.stack`, but `${HOME}/.stack`, which
 is `${workpath}/.home/.stack` for both the `macports` build user and
 `root` in the destroot phase, since we set `HOME` explicitly to
 `${workpath}/.home` for builds. The PG is not touching anything outside of
 its workpath, luckily. It would be totally unacceptable if it did.

-- 
Ticket URL: <https://trac.macports.org/ticket/62228#comment:8>
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