stack.yaml.lock is not created when --resolver option is used.

[debug-ito]

I use stack 2.5.1 on Linux.

stack doesn't create stack.yaml.lock file when --resolver option is used.

For example, the command stack clean (with stack.yaml file in the working directory) creates stack.yaml.lock file. stack --resolver lts-16.11 clean doesn't create stack.yaml.lock file.

Is this an expected behavior?

[mpilgrem]

@debug-ito, thanks for asking. The short answer is: Yes.

When you override the resolver (--resolver option) the default lock file behaviour is set to 'read only'. That happens in Stack.Options.GlobalParser.globalOptsFromMonoid (extract):

  pure GlobalOpts
...
    , globalLockFileBehavior =
        let defLFB =
              case getFirst globalMonoidResolver of
                Nothing -> LFBReadWrite
                _ -> LFBReadOnly
        in  fromFirst defLFB globalMonoidLockFileBehavior
    }

and that is documented online here: https://docs.haskellstack.org/en/stable/global_flags/#-lock-file-option.

[debug-ito]

Thanks for explanation!