Drop support for Ruby 2.0, 2.1, and 2.2

These Ruby versions are no longer supported. Including these in our CI
builds slows the feedback cycle and introduces a maintenance burden for
which there is no clear user base.

1. Ruby 2.0 on Februrary 24th, 2016
2. Ruby 2.1 on April 1st, 2017
3. Ruby 2.2 on June 20th, 2018

[1] https://www.ruby-lang.org/en/news/2016/02/24/support-plan-of-ruby-2-0-0-and-2-1/
[2] https://www.ruby-lang.org/en/news/2017/04/01/support-of-ruby-2-1-has-ended/
[3] https://www.ruby-lang.org/en/news/2018/06/20/support-of-ruby-2-2-has-ended/

.travis.yml

@@ -5,9 +5,6 @@ os:
 rvm:
   - jruby-9.1.9.0
   - rbx-3
-  - 2.0.0
-  - 2.1
-  - 2.2
   - 2.3
   - 2.4
   - 2.5
@@ -42,10 +39,3 @@ matrix:
   - rvm: jruby-9.2.5.0
     jdk: openjdk11
     env: "JAVA_OPTS_FOR_SPECS='--add-opens java.base/java.io=org.jruby.dist --add-opens java.base/sun.nio.ch=org.jruby.dist'"
-  exclude:
-    # Travis does not provide 1.9.3 on OSX
-  - rvm: 1.9.3
-    os: osx
-    # Travis does not provide 2.0.0 on it latest version of OSX
-  - rvm: 2.0.0
-    os: osx

CHANGELOG.md

@@ -1,3 +1,7 @@
+### dev / unreleased
+
+* Drop support for Ruby 2.0, 2.1, and 2.2
+
 ### Version 1.0.1 / 2019-02-03
 
 * [#143](https://github.com/enkessler/childprocess/pull/144): Fix installs by adding `rake` gem as runtime dependency

README.md

@@ -12,9 +12,9 @@ a standalone library.
 [![Code Climate](https://codeclimate.com/github/enkessler/childprocess.svg)](https://codeclimate.com/github/enkessler/childprocess)
 [![Coverage Status](https://coveralls.io/repos/enkessler/childprocess/badge.svg?branch=master)](https://coveralls.io/r/enkessler/childprocess?branch=master)
 
-***
-**This project currently needs a new maintainer. If anyone is interested, please contact me, [enkessler](https://github.com/enkessler).**
-***
+# Requirements
+
+* Ruby 2.3+, JRuby 9+
 
 # Usage
 

appveyor.yml

@@ -2,24 +2,6 @@ version: '1.0.{build}'
 
 environment:
   matrix:
-    - CHILDPROCESS_POSIX_SPAWN: true
-      CHILDPROCESS_UNSET: should-be-unset
-      RUBY_VERSION: 200-x64
-    - CHILDPROCESS_POSIX_SPAWN: false
-      CHILDPROCESS_UNSET: should-be-unset
-      RUBY_VERSION: 200-x64
-    - CHILDPROCESS_POSIX_SPAWN: true
-      CHILDPROCESS_UNSET: should-be-unset
-      RUBY_VERSION: 21-x64
-    - CHILDPROCESS_POSIX_SPAWN: false
-      CHILDPROCESS_UNSET: should-be-unset
-      RUBY_VERSION: 21-x64
-    - CHILDPROCESS_POSIX_SPAWN: true
-      CHILDPROCESS_UNSET: should-be-unset
-      RUBY_VERSION: 22-x64
-    - CHILDPROCESS_POSIX_SPAWN: false
-      CHILDPROCESS_UNSET: should-be-unset
-      RUBY_VERSION: 22-x64
     - CHILDPROCESS_POSIX_SPAWN: true
       CHILDPROCESS_UNSET: should-be-unset
       RUBY_VERSION: 23-x64

childprocess.gemspec

@@ -19,6 +19,8 @@ Gem::Specification.new do |s|
   s.test_files    = `git ls-files -- spec/*`.split("\n")
   s.require_paths = ["lib"]
 
+  s.required_ruby_version = '>= 2.3.0'
+
   s.add_development_dependency "rspec", "~> 3.0"
   s.add_development_dependency "yard", "~> 0.0"
   s.add_development_dependency 'coveralls', '< 1.0'