Clarified how to finish installation by setting a Ruby version either globally or locally.

This allows to run a single test file more easily, although that could be
done by calling bats directly.

…origin)" message when system ruby is in use

…V_VERSION env var

…ection" logic as per @mislav

…stem_ruby

libexec/rbenv-version: get rid of misleading "set by $(rbenv-version-origin)" message when system ruby is in use

fish ships with a much more capable rbenv completion script since fish 2.0.

Fixes #1212

Looks like the zsh completion script was removed by mistake.

Fixes: rbenv/rbenv#1215
Refs: rbenv/rbenv@569d464

…ve_fish

Re-add zsh completion script and remove fish completion script

Since fish 3.10 at least, the current way of loading rbenv in `fish` is misbehaving, at least in some environments:

```
source: Error encountered while sourcing file '/var/folders/pj/jn249gcn7ddfrjzj2_9mxjhw0000gp/T//.psub.f0iJSWRByB':
source: No such file or directory
```

This changes the initialization to the method recommended by a `fish` developer here: fish-shell/fish-shell#6613 (comment)

Fix fish shell initialization

Silver Searcher respects .gitignore, so having an .agignore file is
redundant. (Both patterns present in .agignore are already present in
.gitignore.)

It's also worth noting that silver searcher uses .agignore _in addition
to_ .gitignore, so removing this file will not cause ag to start
ignoring _additional_ patterns from .gitignore (it's already respecting
those patterns).

Remove .agignore

Spelling fix

GitHub's expected filename is CODE_OF_CONDUCT.md. Whether that is the best name or even the current de facto standard is to be debated. But moving forward, this is likely the filename that will become the most common within the community, as that is the name GitHub expects and suggests.

This simply renames the existing code of conduct file from CONDUCT.md to CODE_OF_CONDUCT.md to conform to GitHub's preference.

Rename CONDUCT.md to CODE_OF_CONDUCT.md

bash completion: avoid unintentional globbing

README: reflect changes in rbenv/ruby-build#1402

test/run: handle optional paths/args for bats

Documentation unclear about installing Ruby version

Updated rbenv-doctor url to reflect renaming master branch to main

The syntax `head -NUM` was deprecated in the POSIX standard.
https://pubs.opengroup.org/onlinepubs/9699919799/utilities/head.html

Supply `head -n` flag explicitly

Make work in set -u (nounset) mode

This speeds up subsequent `rbenv init -` executions for the user who
followed these instructions because the shell will no longer have to be
detected each time.

Improve init: warn about missing shell and use it in the template

Before (20 ruby versions, producing 200 shims total):

    mean:    0.124 s
    stdev:   0.003

After:

    mean:    0.090 s
    stdev:   0.004

Speed up rehash

Homebrew places the rbenv executable in a location such as
`/usr/local/bin/rbenv`, which is in PATH. However, that is a symlink to
`/usr/local/Cellar/rbenv/<VERSION>/bin/rbenv`, which is itself a symlink to
`/usr/local/Cellar/rbenv/<VERSION>/libexec/rbenv`. Upon executing, rbenv
will add its own directory to PATH so that it can easily invoke its
subcommands.

When generating shims during `rbenv rehash`, rbenv will try to put the
absolute path to itself inside each shim so that shims would work even
if rbenv itself isn't in PATH. Under Homebrew, rbenv's directory will be
the versioned directory in Homebrew's Cellar. However, due to Homebrew's
auto-cleanup functionality, shims generated this way will be broken
after upgrading rbenv because of the versioned Cellar path.

This changes how rbenv discovers itself in PATH: it will look at the
original PATH, not in the one modified by rbenv, with the intention of
excluding results under rbenv's own `libexec/`. If rbenv wasn't found in
PATH, return the absolute path to rbenv's own `bin/rbenv`.

Have shims survive upgrades via Homebrew

Sort versions semantically in rbenv versions

Fixes #1130

* commit 'rbenv-tags/v1.2.0':
  rbenv 1.2.0
  Clarify bash config for Ubuntu Desktop vs. other platforms
  💅 Clean up version sorting and add test
  Sort versions semantically in rbenv versions
  Have shims survive symlinked rbenv updates a la Homebrew
  GitHub now auto-generates a Table of Contents
  Speed up rehash
  Have `rbenv init` print instructions that hardcode the detected shell
  Supply `head -n` flag explicitly
  Update rbenv-doctor link master -> main
  Updated rbenv-doctor url to reflect renaming master branch to main
  Fix link to rbenv-doctor
  test(init): remove misleading arg in detect from parent shell case
  feat(init): strip -<suffix> when autodetecting shell
  [DOCS] Typo and formatting fix.
  Use a better PS4 as recommeneded by Bash Hackers Wiki
  Update README.md
  README: reflect changes in rbenv/ruby-build#1402
  Rename CONDUCT.md to CODE_OF_CONDUCT.md
  bash completion: avoid unintentional globbing
  Make work in set -u (nounset) mode
  Spelling fix
  Remove agignore
  Fix fish instructions test
  Remove another `fish` psub usage
  Fix fish shell initialization
  Use `actions/checkout` v2
  Run CI for pull requests from forks
  Re-add zsh completion script and remove fish completion script
  Remove fish completion script
  Fix (revert) test/version-origin.bats
  libexec/rbenv-version{,-origin}: move "missing rbenv-version-file detection" logic as per @mislav
  Fix tests for #1203
  libexec/rbenv-version{,-origin}: fix earlier commit to allow for RBENV_VERSION env var
  libexec/rbenv-version: get rid of misleading "set by $(rbenv-version-origin)" message when system ruby is in use
  test/run: handle optional paths/args for bats
  Documentation unclear