Mark global versions in the output of list command

[maxdanilov]

Expected behavior

Would be user friendly if the list command would somehow mark the currently selected versions of the environments.

asdf list

golang
    1.13.2
  * 1.13.4
groovy
    apache-groovy-binary-2.4.12
  * apache-groovy-binary-2.5.8

This way it's clear that go 1.13.4 and groovy 2.5.8 would be used.
I'm aware of asdf current, but it only shows the currently selected versions, without the context of what else is installed.

Actual behavior

asdf list

golang
  1.13.2
  1.13.4
groovy
  apache-groovy-binary-2.4.12
  apache-groovy-binary-2.5.8

Environment

OS: MacOS 10.15.1

asdf version: v0.7.5

[cho-m]

So there was a PR for this (#761 and duplicate #762), but it didn't get much traction.
It would be nice to get a review on one of those to see if a different aesthetic/solution is needed.

The available PR output looks like a whitespace-lacking chruby-style output.
It should also be possibly to extend PR to create pyenv/rbenv-style output.

One possible demerit would be the fact that asdf current is slower than asdf list. By running current inside list, the command will be noticeably slower:

❯ hyperfine 'asdf list' 'asdf current'
Benchmark #1: asdf list
  Time (mean ± σ):      22.8 ms ±   0.6 ms    [User: 6.6 ms, System: 13.4 ms]
  Range (min … max):    20.8 ms …  25.3 ms    114 runs

Benchmark #2: asdf current
  Time (mean ± σ):     189.8 ms ±   1.7 ms    [User: 57.3 ms, System: 142.6 ms]
  Range (min … max):   188.4 ms … 194.8 ms    15 runs

Summary
  'asdf list' ran
    8.33 ± 0.22 times faster than 'asdf current'


❯ hyperfine --warmup 3 'asdf list ruby' 'asdf current ruby'
Benchmark #1: asdf list ruby
  Time (mean ± σ):      12.6 ms ±   0.3 ms    [User: 4.3 ms, System: 6.7 ms]
  Range (min … max):    11.2 ms …  13.5 ms    205 runs

Benchmark #2: asdf current ruby
  Time (mean ± σ):      61.7 ms ±   0.5 ms    [User: 18.7 ms, System: 45.4 ms]
  Range (min … max):    60.8 ms …  62.8 ms    46 runs

Summary
  'asdf list ruby' ran
    4.88 ± 0.13 times faster than 'asdf current ruby'

---

This "marker" feature is available in most other version managers. The exact output is different based on tool, but here is a compilation of examples from some alternatives. It may be worth chiming-in on what output is best:

1. Ruby - chruby

   $ chruby 1.9.3
   $ chruby
    * ruby-1.9.3-p392
      jruby-1.7.0
      rubinius-2.0.0-rc1

2. Ruby - RVM

   $ rvm list
   
     rvm rubies
   
      * ruby-1.9.3-p484 [ x86_64 ]
        ruby-2.0.0-p481 [ x86_64 ]
     => ruby-2.1.1 [ x86_64 ]
   
     # => - current
     # =* - current && default
     #  * - default

3. Ruby - rbenv

   $ rbenv versions
     1.8.7-p352
     1.9.2-p290
   * 1.9.3-p327 (set by /Users/sam/.rbenv/version)

4. Python - pyenv - forked from rbenv, so output is similar

   $ pyenv versions
     2.7.10
   * 3.5.0 (set by /Users/yuu/.pyenv/version)
     miniconda3-3.16.0
     pypy-2.6.0

5. NodeJS - nvm - also has color-coded output

   $ nvm ls
          v10.15.0
   ->     v11.10.0
          system
   ...

6. Go - gvm

   $ gvm list
   
   gvm gos (installed)
   
      go1.12.8
   => system

7. Rust - rustup - shows active toolchain and lists global default.

   ❯ rustup show
   Default host: aarch64-apple-darwin
   rustup home:  /Users/cho-m/.local/share/rustup
   
   installed toolchains
   --------------------
   
   stable-aarch64-apple-darwin (default)
   nightly-aarch64-apple-darwin
   
   active toolchain
   ----------------
   
   nightly-aarch64-apple-darwin (directory override for '/Users/cho-m/Workspace/test')
   rustc 1.52.0-nightly (e37a13cc3 2021-02-28)