Re-add support for Ruby 2.4+ (#6)

.github/workflows/ci.yaml

@@ -25,11 +25,7 @@ jobs:
       matrix:
         ## Due to https://github.com/actions/runner/issues/849,
         ## we have to use quotes for '3.0'
-        ruby:
-          - '2.6'
-          - '2.7'
-          - '3.0'
-          - '3.1'
+        ruby: ['2.4', '2.5', '2.6', '2.7', '3.0', '3.1']
     steps:
     - uses: actions/checkout@v2
     - name: Set up Ruby

.rubocop.yml

@@ -13,7 +13,7 @@ inherit_mode:
 AllCops:
   DisplayCopNames: true
   DisplayStyleGuide: true
-  TargetRubyVersion: 2.6
+  TargetRubyVersion: 2.4
   SuggestExtensions: false
   NewCops: enable
 

Gemfile

@@ -11,9 +11,9 @@ group :test do
   gem 'bundler', '~> 2.0'
   gem 'rake', '~> 13.0'
   gem 'rspec', '~> 3.0'
-  gem 'simplecov', '~> 0.21.0'
+  gem 'simplecov', '~> 0.18.0'
 
-  gem 'rubocop', '~> 1.21.0'
+  gem 'rubocop', '~> 1.12.0'
   gem 'rubocop-packaging', '~> 0.5.0'
   gem 'rubocop-performance', '~> 1.0'
   gem 'rubocop-rspec', '~> 2.0'

faraday-retry.gemspec

@@ -29,5 +29,5 @@ Gem::Specification.new do |spec|
 
   spec.files = Dir['lib/**/*', 'README.md', 'LICENSE.md', 'CHANGELOG.md']
 
-  spec.required_ruby_version = '>= 2.6', '< 4'
+  spec.required_ruby_version = '>= 2.4', '< 4'
 end

lib/faraday/retry/middleware.rb

@@ -71,7 +71,7 @@ def retry_if
         end
 
         def retry_block
-          self[:retry_block] ||= proc {}
+          self[:retry_block] ||= proc {} # rubocop:disable Lint/EmptyBlock
         end
 
         def retry_statuses

spec/faraday/retry/middleware_spec.rb

@@ -1,5 +1,11 @@
 # frozen_string_literal: true
 
+PartClass = if defined?(Faraday::Multipart::FilePart)
+              Faraday::Multipart::FilePart
+            else
+              Faraday::FilePart
+            end
+
 RSpec.describe Faraday::Retry::Middleware do
   let(:calls) { [] }
   let(:times_called) { calls.size }
@@ -177,7 +183,7 @@
 
     it 'FilePart: should rewind files on retry' do
       io = StringIO.new('Test data')
-      filepart = Faraday::Multipart::FilePart.new(io, 'application/octet/stream')
+      filepart = PartClass.new(io, 'application/octet/stream')
 
       rewound = 0
       rewind = -> { rewound += 1 }
@@ -191,7 +197,7 @@
 
     it 'UploadIO: should rewind files on retry' do
       io = StringIO.new('Test data')
-      upload_io = Faraday::Multipart::FilePart.new(io, 'application/octet/stream')
+      upload_io = PartClass.new(io, 'application/octet/stream')
 
       rewound = 0
       rewind = -> { rewound += 1 }