Re: [RFC PATCH 0/2] teach `worktree list` to mark locked worktrees

From: Eric Sunshine <sunshine@sunshineco.com>
Date: Sep 30, 2020, 07:19 UTC
Message-ID: <CAPig+cQXkP8vTNR+LJ4fZRT-an0vEgKxcFpfi+aQ-BdipTgq=A@mail.gmail.com>
In-Reply-To: <20200928154953.30396-1-rafaeloliveira.cs@gmail.com>

On Mon, Sep 28, 2020 at 11:50 AM Rafael Silva <rafaeloliveira.cs@gmail.com> wrote:

> This patch series introduces a new information on the git `worktree list`
> command output, to mark when a worktree is locked with a (locked) text mark.

Thanks for working on this. "locked" is one of several additional annotations to the output of "git worktree list" which have long been envisioned. For reference, here are some earlier messages related to this topic:

[1]: https://lore.kernel.org/git/CAPig+cTTrv2C7JLu1dr4+N8xo+7YQ+deiwLDA835wBGD6fhS1g@mail.gmail.com/ [2]: https://lore.kernel.org/git/CAPig+cQF6V8HNdMX5AZbmz3_w2WhSfA4SFfNhQqxXBqPXTZL+w@mail.gmail.com/ [3]: https://lore.kernel.org/git/CAPig+cSGXqJuaZPhUhOVX5X=LMrjVfv8ye_6ncMUbyKox1i7QA@mail.gmail.com/ [4]: https://lore.kernel.org/git/CAPig+cTitWCs5vB=0iXuUyEY22c0gvjXvY1ZtTT90s74ydhE=A@mail.gmail.com/

I'll leave a few review comments to supplement those already by Junio.

Show 6 quoted lines

> This is the output of the worktree list with locked marker:
>
>  $ git worktree list
>  /repo/to/main        abc123 [master]
>  /path/to/unlocked-worktree1 456def [brancha]
>  /path/to/locked-worktree   123abc (detached HEAD) (locked)

In [2], I gave an example of output similar to this but without encapsulating "locked" within parentheses:

    % git worktree list
    giggle     89ea799ffc [master]
    ../bobble  f172cb543d [feature1] locked
    ../fumple  6453c84b7d (detached HEAD) prunable

I omitted the parentheses partly due to the extra noise they introduce, but mostly because I foresaw that a single entry might eventually have multiple annotations, for instance:

    % git worktree list
    giggle     89ea799ffc [master]
    ../bobble  f172cb543d [feature1] locked prunable

in which case, the eyes glide over "locked prunable" a bit more easily than over "(locked) (prunable)" or "(locked, prunable)" or some such. Generally speaking, "the less noise, the better".

> This patches are marked with RFC mainly due to:
>
>  - Perhaps the `(locked)` marker is not the best suitable way to output
>   this information and we might need to come with a better way.

Taking [2] into consideration, I think it's fine to annotate the line with "locked" (sans the parentheses), and it's compatible with the the verbose mode, also proposed by [2]:

    % git worktree list -v
    giggle     89ea799ffc [master]
    ../bobble  f172cb543d [feature1]
        locked: worktree on removable media
    ../fumple  6453c84b7d (detached HEAD)
        prunable: directory does not exist

in which case the short "locked" annotation gets moved to the next line, indented, and expanded to include the reason, if available (otherwise would probably not be moved to the next line).

I'm not suggesting that this patch series implement verbose mode, but bring it to attention to make sure we don't paint ourselves into a corner when deciding how the "locked" annotation should be presented.

>  - I am a new contributor to the code base, still learning a lot of git
>   internals data structure and commands. Likely this patch will require
>   updates.

Under normal circumstances, I would be hesitant to accept a contribution which makes an addition to the human-consumable "git worktree list" output without also making the corresponding addition to the --porcelain format. Thus, for instance, I would expect the porcelain format to be updated, as well, to produce output such as this (taken from [4]):

    worktree /blah
    branch refs/heads/blah
    locked Sneaker-net removable storage\nNot always mounted

That's a bit complicated because the lock reason may need escaping if it contains special characters (such as the newline in the example). Thus, I'm a bit hesitant to expect such a change from a newcomer.

More problematic, though, with regard to the porcelain format is that the documentation is so woefully under-specified, as explained in [4], that some people may interpret it as meaning that no additional information can be added. I'm not particularly sympathetic to that view since the intention from the start was that the porcelain format should be extensible[4], thus adding new attributes should be allowed. But I'm hesitant to ask a newcomer to undertake the task of addressing these shortcomings. As such, I think it may be okay merely to change the human-consumable output as this series does, and leave porcelain output for a later date if someone wants to tackle it.

A reason that it would be nice to address the shortcomings of porcelain format is because there are several additional pieces of information it could be providing. Summarizing from [1], in addition to the worktree path, its head, checked out branch, whether its bare or detached, for each worktree, porcelain could also show:

    * whether it is locked
      - the lock reason (if available)
      - and whether the worktree is currently accessible (mounted)
    * whether it can be pruned
      - and the prune reason if so
    * worktree ID (the <id> of .git/worktrees/<id>/)