spago shouldn't try to create $HOME if it doesn't exist

[dhess]

While trying to make spago test work in a nixpkgs derivation, I ran into this issue:

[error] Directory "/" is not accessible. Permissions {readable = True, writable = False, executable = False, searchable = True}

This happens because, when nixpkgs builds a derivation, it sets $HOME to a non-existent location:

2020-12-14 14:15:37.905847: [debug] Running `getGlobalCacheDir`
@(src/Spago/RunEnv.hs:44:7)
2020-12-14 14:15:37.906423: [debug] Directory "/homeless-shelter/.cache/spago" does not exist, creating...
@(src/Spago/Prelude.hs:189:7)
2020-12-14 14:15:37.906462: [debug] Directory "/homeless-shelter/.cache" does not exist, creating...
@(src/Spago/Prelude.hs:189:7)
2020-12-14 14:15:37.906487: [debug] Directory "/homeless-shelter" does not exist, creating...
@(src/Spago/Prelude.hs:189:7)
2020-12-14 14:15:37.906559: [error] Directory "/" is not accessible. Permissions {readable = True, writable = False, executable = False, searchable = True}
@(src/Spago/Prelude.hs:125:13)

Note that spago tries to do this even when spago test is run with --global-cache=skip!

So I think there are 2 issues here:

1. Don't go any further up the path than $HOME when trying to create the global cache directory.
2. --global-cache=skip should not try to create $HOME/.cache/spago at all.

[f-f]

It sounds like this is a duplicate of #704, which was fixed in #705?

The fix will be shipped in the upcoming 0.18 release, which I'm about to cut.

[dhess]

Sorry! I searched for a similar issue, but obviously not well enough!

[f-f]

No worries at all 🙂