Fixes issue where fnm print the node version string when using fish shell in non-interactive mode

[eelcocramer]

This week I ran into an issue with Neovide, a neovim gui (also written in rust).

I proposed GH-955 but did not feel this was the right fix for this issue, so this PR replaces that.

Neovide starts neovim in a sub-shell and uses the neovim --embed mode to read and write msgpack messages to and from stdout.

When I start Neovide in a folder with a .nvmrc that defines a node version that is not my default, fnm prints a message and that ends up in the communication between Neovide and nvim and makes it crash.

Neovide runs a non-interactive shell, and in that mode your shell init scripts are not supposed to print anything. In that mode, the shell typically don't ready .bashrc and similar. However, for the fish shell, it seems like it always reads config.fish (fish-shell/fish-shell#5394).

This PR adds changes the behaviour of fnm env --use-on-cd for the fish shell to add a conditional check whether the shell is interactive or not. If fish is in non-interactive mode fnm use is started with a new switch --silent that will not let fnm output the version string even if the version will change.

[changeset-bot]

🦋 Changeset detected

Latest commit: 92d7605

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
fnm	Minor

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[Schniz]

There is log level configuration that can be set to error, which will do exactly what you want, or am I missing something?

[eelcocramer]

Maybe. But then the log level should be set to error as a default in non-interactive mode right?

[Schniz]

Hmmm…. Define non interactive? fnm is not a shell. It’s not a debug statement, it’s an info/stdout kind of thing. I don’t think fnm should be quiet by default

[eelcocramer]

Ah sorry for being verbose. I meant when the fish shell is running non-interactive, i.e. not connected to a keyboard and in that case fnm probably runs in the background somewhere and should be silent.

But another way to achieve that could be to change the logging level here in case the shell runs non-interactively.

[Schniz]

sorry for only circling back to it now, can we maybe put it --log-level=error here to avoid info messages?

[Schniz]

any news on the log-level usage?