Drop support for Ruby before 3.0

Use argument forwarding for middleware and delegators instead of ruby2_keywords. Remove obsolete compatibility branches and test only supported Ruby versions.

Assisted-By: devx/9a5ced6c-36f2-46e3-a662-1765c7341b0e

Author: samuel-williams-shopify

.github/workflows/test.yaml

@@ -13,10 +13,6 @@ jobs:
         os:
           - ubuntu-latest
         ruby:
-          - '2.4'
-          - '2.5'
-          - '2.6'
-          - '2.7'
           - '3.0'
           - '3.1'
           - '3.2'

.rubocop.yml

@@ -2,7 +2,7 @@ require:
   - rubocop-packaging
 
 AllCops:
-  TargetRubyVersion: 2.4
+  TargetRubyVersion: 3.0
   DisabledByDefault: true
   Exclude:
     - '**/vendor/**/*'

CHANGELOG.md

@@ -20,6 +20,7 @@ All notable changes to this project will be documented in this file. For info on
 
 ### Changed
 
+- Require Ruby 3.0 or newer and replace `ruby2_keywords` with argument forwarding.
 - Raise before exceeding a part limit, not after. ([#2362](https://github.com/rack/rack/pull/2362), [@matthew-puku](https://github.com/matthew-puku))
 - Rack::Deflater now uses a fixed GZip mtime value. ([#2372](https://github.com/rack/rack/pull/2372), [@bensheldon](https://github.com/bensheldon))
 - Multipart parser drops support for RFC 2231 `filename*` parameter (prohibited by RFC 7578) and now properly handles UTF-8 encoded filenames via percent-encoding and direct UTF-8 bytes. ([#2398](https://github.com/rack/rack/pull/2398), [@wtn](https://github.com/wtn))

Gemfile

@@ -15,8 +15,6 @@ group :doc do
   else
     gem "rdoc"
   end
-
-  gem "psych", "= 3.0.2" if RUBY_VERSION[0..2] == "2.5"
 end
 
 group :test do

lib/rack/body_proxy.rb

@@ -42,22 +42,19 @@ def closed?
     end
 
     # Delegate missing methods to the wrapped body.
-    def method_missing(method_name, *args, &block)
+    def method_missing(method_name, ...)
       case method_name
       when :to_str
         super
       when :to_ary
         begin
-          @body.__send__(method_name, *args, &block)
+          @body.__send__(method_name, ...)
         ensure
           close
         end
       else
-        @body.__send__(method_name, *args, &block)
+        @body.__send__(method_name, ...)
       end
     end
-    # :nocov:
-    ruby2_keywords(:method_missing) if respond_to?(:ruby2_keywords, true)
-    # :nocov:
   end
 end

lib/rack/builder.rb

@@ -156,18 +156,15 @@ def self.app(default_app = nil, &block)
     # All requests through to this application will first be processed by the middleware class.
     # The +call+ method in this example sets an additional environment key which then can be
     # referenced in the application if required.
-    def use(middleware, *args, &block)
+    def use(middleware, ...)
       if @map
         mapping, @map = @map, nil
         @use << proc { |app| generate_map(app, mapping) }
       end
-      @use << proc { |app| middleware.new(app, *args, &block) }
+      @use << proc { |app| middleware.new(app, ...) }
 
       nil
     end
-    # :nocov:
-    ruby2_keywords(:use) if respond_to?(:ruby2_keywords, true)
-    # :nocov:
 
     # Takes a block or argument that is an object that responds to #call and
     # returns a Rack response.

lib/rack/deflater.rb

@@ -27,7 +27,7 @@ module Rack
   # encoding.
   class Deflater
 
-    GZIP_MTIME = RUBY_VERSION >= "2.7" ? 0 : 1
+    GZIP_MTIME = 0
 
     # Creates Rack::Deflater middleware. Options:
     #

lib/rack/headers.rb

@@ -199,34 +199,26 @@ def values_at(*keys)
       keys.map{|key| self[key]}
     end
 
-    # :nocov:
-    if RUBY_VERSION >= '2.5'
-    # :nocov:
-      def slice(*a)
-        h = self.class.new
-        a.each{|k| h[k] = self[k] if has_key?(k)}
-        h
-      end
+    def slice(*a)
+      h = self.class.new
+      a.each{|k| h[k] = self[k] if has_key?(k)}
+      h
+    end
 
-      def transform_keys(&block)
-        dup.transform_keys!(&block)
-      end
+    def transform_keys(&block)
+      dup.transform_keys!(&block)
+    end
 
-      def transform_keys!
-        hash = self.class.new
-        each do |k, v|
-          hash[yield k] = v
-        end
-        replace(hash)
+    def transform_keys!
+      hash = self.class.new
+      each do |k, v|
+        hash[yield k] = v
       end
+      replace(hash)
     end
 
-    # :nocov:
-    if RUBY_VERSION >= '3.0'
-    # :nocov:
-      def except(*a)
-        super(*a.map!{|key| downcase_key(key)})
-      end
+    def except(*a)
+      super(*a.map!{|key| downcase_key(key)})
     end
 
     private

lib/rack/mock_response.rb

@@ -23,12 +23,9 @@ def initialize(args)
         @secure = args["secure"]
       end
 
-      def method_missing(method_name, *args, &block)
-        @value.send(method_name, *args, &block)
+      def method_missing(method_name, ...)
+        @value.send(method_name, ...)
       end
-      # :nocov:
-      ruby2_keywords(:method_missing) if respond_to?(:ruby2_keywords, true)
-      # :nocov:
 
       def respond_to_missing?(method_name, include_all = false)
         @value.respond_to?(method_name, include_all) || super

lib/rack/multipart/uploaded_file.rb

@@ -74,12 +74,9 @@ def respond_to_missing?(*args)
       end
 
       # Delegate method missing calls to the tempfile.
-      def method_missing(method_name, *args, &block) #:nodoc:
-        @tempfile.__send__(method_name, *args, &block)
+      def method_missing(method_name, ...) #:nodoc:
+        @tempfile.__send__(method_name, ...)
       end
-      # :nocov:
-      ruby2_keywords(:method_missing) if respond_to?(:ruby2_keywords, true)
-      # :nocov:
     end
   end
 end