Remove ffi conditional install on Windows platforms

CHANGELOG.md

@@ -1,3 +1,9 @@
+### dev (unreleased)
+
+* Remove extension to conditionally install `ffi` gem on Windows platforms
+* Remove runtime dependency on `rake` gem
+* Remove unused `rubyforge_project` from gemspec
+
 ### Version 2.0.0 / 2019-07-11
 
 * [#148](https://github.com/enkessler/childprocess/pull/148): Drop support for Ruby 2.0, 2.1, and 2.2

Gemfile

@@ -3,6 +3,9 @@ source 'http://rubygems.org'
 # Specify your gem's dependencies in child_process.gemspec
 gemspec
 
+# Used for local development/testing only
+gem 'rake'
+
 if RUBY_VERSION =~ /^1\./
   gem 'tins', '< 1.7' # The 'tins' gem requires Ruby 2.x on/after this version
   gem 'json', '< 2.0' # The 'json' gem drops pre-Ruby 2.x support on/after this version

README.md

@@ -16,6 +16,8 @@ a standalone library.
 
 * Ruby 2.3+, JRuby 9+
 
+Windows users **must** ensure the `ffi` gem (`>= 1.0.11`) is installed in order to use ChildProcess.
+
 # Usage
 
 The object returned from `ChildProcess.build` will implement `ChildProcess::AbstractProcess`.

childprocess.gemspec

@@ -23,9 +23,4 @@ Gem::Specification.new do |s|
   s.add_development_dependency "rspec", "~> 3.0"
   s.add_development_dependency "yard", "~> 0.0"
   s.add_development_dependency 'coveralls', '< 1.0'
-
-  s.add_runtime_dependency 'rake', '< 13.0'
-
-  # Install FFI gem if we're running on Windows
-  s.extensions = 'ext/mkrf_conf.rb'
 end

lib/childprocess/errors.rb

@@ -16,8 +16,8 @@ class LaunchError < Error
 
   class MissingFFIError < Error
     def initialize
-      message = "FFI is a required pre-requisite for posix_spawn, falling back to default implementation. " +
-                "Please add it to your deployment to unlock this functionality. " +
+      message = "FFI is a required pre-requisite for Windows or posix_spawn support in the ChildProcess gem. " +
+                "Ensure the `ffi` gem is installed. " +
                 "If you believe this is an error, please file a bug at http://github.com/enkessler/childprocess/issues"
 
       super(message)

lib/childprocess/version.rb

@@ -1,3 +1,3 @@
 module ChildProcess
-  VERSION = '2.0.0'
+  VERSION = '3.0.0'
 end

lib/childprocess/windows.rb

@@ -1,6 +1,11 @@
-require "ffi"
 require "rbconfig"
 
+begin
+  require 'ffi'
+rescue LoadError
+  raise ChildProcess::MissingFFIError
+end
+
 module ChildProcess
   module Windows
     module Lib