Ruby | EOL Ruby를 설치할 수 없습니다.

EOL => End Of Life
즉, 2.4 이하 버전의 루비다.
Ruby Lifecycle (EOL)
2.35 rbenv 설치를 시도할 때 다음 오류 로그와 함께 실패했습니다.
그래서 이 글에는 원인과 해결 방법이 기재되어 있다.
아, 겸사겸사 말씀드리지만, 저는 맥입니다.

~ $ rbenv install 2.3.5
ruby-build: using openssl from homebrew
Downloading ruby-2.3.5.tar.bz2...
-> https://cache.ruby-lang.org/pub/ruby/2.3/ruby-2.3.5.tar.bz2
Installing ruby-2.3.5...
ruby-build: using readline from homebrew

BUILD FAILED (OS X 10.15 using ruby-build 20191105)

Inspect or clean up the working tree at /var/folders/6n/8_hv1dkd2bvg1smftl8zybx40000gn/T/ruby-build.20191109131611.38543.IPfI1B
Results logged to /var/folders/6n/8_hv1dkd2bvg1smftl8zybx40000gn/T/ruby-build.20191109131611.38543.log

Last 10 log lines:
installing capi-docs:         /Users/anthony_kiedis/.rbenv/versions/2.3.5/share/doc/ruby
The Ruby openssl extension was not compiled.
ERROR: Ruby install aborted due to missing extensions
Configure options used:
  --prefix=/Users/anthony_kiedis/.rbenv/versions/2.3.5
  --with-openssl-dir=/usr/local/opt/[email protected]
  --with-readline-dir=/usr/local/opt/readline
  CC=clang
  LDFLAGS=-L/Users/anthony_kiedis/.rbenv/versions/2.3.5/lib
  CPPFLAGS=-I/Users/anthony_kiedis/.rbenv/versions/2.3.5/include

까닭

최신 루비-build 2019 1105는 [email protected]에 의존하지만 2.4 이하의 루비가 이에 대응하지 않기 때문이다

참고 자료

ruby-build (Homebrew Formulae)

Depends on:
autoconf
2.69
Automatic configure script builder
[email protected]
1.1.1d
Cryptography and SSL/TLS Toolkit
pkg-config
0.29.2
Manage compile and link flags for libraries
readline
8.0.1
Library for command-line editing

rbenv/ruby-build

The openssl extension of Ruby version before 2.4 is not compatible with OpenSSL 1.1.x.

해결책

여기에 기재된 것과 같다.
Cannot install Ruby versions < 2.4 because of [email protected] dependency #1353

# 対応しているopenssl 1.0.2を入れます
$ brew install openssl

# 手動で使うopensslの場所を指定してrbenv installします
$ RUBY_CONFIGURE_OPTS="--with-openssl-dir=/usr/local/opt/openssl" rbenv install 2.3.5

# ちなみに僕はfishユーザなので、fishを使っている人は以下のコマンド
$ env RUBY_CONFIGURE_OPTS=--with-openssl-dir=/usr/local/opt/openssl/ rbenv install 2.3.5

이상