setup-info field in stack.yaml not consulted

[ndmitchell]

Using stack 1.3.2 on Windows 64bit, I have a stack.yaml file containing setup-info: http://example.com/none.yaml. I have disabled access to raw.githubusercontent.com. If I run either stack setup or stack build then I get an error about not being able to reach raw.githubusercontent.com, rather than a 404 failing to download example.com/none.yaml. If I use the flag --setup-info-yaml with example.com then it fails witha 404 as expected. The documentation suggests these two settings are equivalent, but they don't seem to be.

[mgsloan]

Hmm, indeed it seems that --setup-info-yaml overrides the default url, whereas the setup-info field extends the list of configs to load.

I wonder how impactful it would be to change this semantics such that the default url doesn't get used when setup-info is manually specified. Seems like a reasonable change to me

[borsboom]

In the case of a inline setup-info, it probably should extend the default configs, since that's commonly used to add one custom GHC bindist (e.g. if you want to test the latest GHC release candidate). For the cases where it references an external YAML URL, you're right that the more common use case would probably be to totally override the default URL. Potentially bit confusing to have the same field behave a bit differently in these two cases though.

[AleXoundOS]

Still confusing.
I have setup-info: "http://my-local-server/stack-setup.yaml" in both config.yaml and project's stack.yaml. However none of them help in case of running stack setup. I still have to manually give --stack-setup-yaml=http://my-local-server/stack-setup.yaml option to stack setup on the first run.

[borsboom]

I think that field expects the setup info to be inline, not point to a separate file/URL. The fact that's it's silently ignoring an entry is a bug though, and being able to point it to a separate file/URL would be a helpful feature.

[dbaynard]

So to resolve this issue,

1. Supplying invalid setup-info should lead to an error (fixing the bug), and
2. If a path is supplied (to setup-info or an equivalent key) that should be treated as the stack-setup.yaml file.

Is that correct?

[borsboom]

Yes, I'd say (1) is required and (2) would be a nice feature but needs a bit of thought. Inline setup-info augments the downloaded setup-info, whereas the stack --setup-info-yaml replaces it, so it would be confusing to have both behaviours in the same setup-info field.

[istathar]

@borsboom can I suggest that https://docs.haskellstack.org/en/stable/yaml_configuration/#setup-info be updated to explicitly say that you cannot use the field in ~/.stack/config.yaml / stack.yaml to override with your own setup-info.yaml file and that you have to use the command-line option?

[alternately, if there was a way to defeat the default value before appending the supplied values, that would be good too]

We just killed a lot of time trying to figure out why

setup-info: /home/username/.stack/setup-info.yaml

wasn't working. I understand now, but it is very confusing. Fortunately specifying on the command-line does work.

AfC

[borsboom]

Alright, I clarified the docs in #4589. I agree it would be nice to support replacing it from the config file too.