Hello everybody, this is a casual issue and not immediately detrimental.

In a stack.yaml, if you set a source code location to a git commit that doesn't exist on the referenced repo, then you get the "could not parse object" error, which led me to believe I had somehow pasted my commit hash wrong. For instance, if you have this in your stack.yaml:

packages:
- '.'
- location:
    git: https://github.com/athanclark/foo
    commit: 8e22ca206e9fc8fd7b903afa8b073120f8897793
  extra-dep: true

and you tried to stack build, you would get the error:

Running /usr/bin/git reset --hard 8e22ca206e9fc8fd7b903afa8b073120f8897793 exited with ExitFailure 128

fatal: Could not parse object '8e22ca206e9fc8fd7b903afa8b073120f8897793'.

Which is misleading.