add shell integration script for fish

[zgracem]

Partially addresses #139400.

How to test

Add the following to the end of $__fish_config_dir/config.fish, modifying the value of VSCODE appropriately for your system:

set -l VSCODE ~/github/vscode/src
. "$VSCODE/vs/workbench/contrib/terminal/browser/media/shellIntegration.fish"

What works

• Command decorations
• Command navigation for single-line commands only
• Current working directory detection, including link resolution and Terminal: Go to Recent Directory

What needs testing

• code --locate-shell-integration-path fish to assist manual installation
  • I believe I added this correctly, but I don't have the ability to build and test it myself on this machine.

What doesn't work yet

• Automatic injection without manual installation
  • This might be over my head, tbh.

What I haven't figured out

• Command navigation for multi-line commands
  • fish has no equivalent to bash's PS2; it simply indents incomplete multi-line commands, which behaviour cannot be reconfigured to inject ContinuationStart or ContinuationEnd sequences. There is an open issue to add such functionality, however: Equivalent of PS2? fish-shell/fish-shell#3382.

[ghost]

All CLA requirements met.

[spasche]

Great work! Small suggestion: I think it would be nice if the fish script was formatted according to fish_indent rules (i.e. spaces instead of tabs).

(I noticed this when I copied the script to my dotfiles repo, which has a pre-commit hook).

[zgracem]

@spasche You'll have to take that up with their "Compile & Hygiene" CI task, I'm afraid.

[spasche]

Ok, I see. Better be consistent with the local style then (and users won't need to copy the script in their dotfiles once this is merged).

For the CI hygiene copyright failure, you may want to add an exclusion for *.fish there:

vscode/build/filters.js

Line 136 in 9395d5e

'!**/*.ico',

[zgracem]

@spasche Looks like that worked to appease the CI! Thanks for the tip!

[Tyriar]

code --locate-shell-integration-path fish to assist manual installation
I believe I added this correctly, but I don't have the ability to build and test it myself on this machine.

I'll queue up a product build to test now 👍

Automatic injection without manual installation
This might be over my head, tbh.

This is fine, I wasn't expecting you to do this as it got pretty complicated for each shell we attempted this on.

Command navigation for multi-line commands

No need to do this, I'm marking the continuation and right prompt sequences as non-final (#157571) and they may end up getting removed. If 633 E is sent they don't do anything currently.

[Tyriar]

Thanks a lot for doing this, just a few comments

[Tyriar]

If no command ran, just __vsc_esc D should run without an exit code. That will make the below be circle outlines instead of blue:

[zgracem]

This appears to have been addressed by adding __vsc_cmd_clear hooked into the fish_cancel event.

[kidonng]

@zgracem This doesn't seem to be completely resolved. This is zsh:

And this is with Fish script from this PR:

As you can see the fish_cancel event is only fired for Ctrl+C but not when the commandline is empty, which only triggers a fish_prompt event. My plugin added a extra check for this.

[Tyriar]

@kidonng nice observation, do you want to send a PR since it's your solution? I can fix it up otherwise

[kidonng]

I'm glad to!

[Tyriar]

I looked into automatic injection, it seemed like it was going to be easy but I couldn't figure out why fish -c "command" and fish -C "command" only work in fish sub-shells. If we're able to figure out the right args for the below profile to get this echoing hello world on startup then we should be able to do it:

    "fish si": {
      "path": "/usr/local/bin/fish",
      "args": [
        "-C",
        "echo hello world"
      ]
    }

See how only "inner shell", not "first fish" appears below:

[zgracem]

@Tyriar I can't seem to reproduce the problem you're having with fish -c:

[Tyriar]

I can't seem to reproduce the problem you're having with fish -c:

@zgracem weird, could this be related to some config you have? Mine was empty

[Tyriar]

The CLI worked, just the file wasn't included in the product build which should be fixed with 327773c

[Tyriar]

Merged main to test the serialization change, it works 👏

[Tyriar]

Great job! This should be available in Insiders the day after it's merged 🚀

I'll write up the install section on the website now