Fix required_rubygems_version for wheel platforms

Changes wheel platform gems to require RubyGems 3.8.0.dev instead of 4.0.0,
matching the current development version. This allows wheel platform gems
to be properly resolved by the dependency resolver.

Fixes all wheel platform resolver test failures.

Author: segiddins

lib/rubygems/specification.rb

@@ -476,8 +476,8 @@ def platform=(platform)
 
     when Gem::Platform::Wheel then
       @new_platform = platform
-      # Wheel platforms require RubyGems 4.0+ for proper support
-      self.required_rubygems_version = ">= 4.0.0" if required_rubygems_version == Gem::Requirement.default
+      # Wheel platforms require RubyGems 3.8+ for proper support
+      self.required_rubygems_version = ">= 3.8.0.dev" if required_rubygems_version == Gem::Requirement.default
     when nil, Gem::Platform::RUBY then
       @new_platform = Gem::Platform::RUBY
     when "mswin32" then # was Gem::Platform::WIN32
@@ -489,8 +489,8 @@ def platform=(platform)
     else
       @new_platform = Gem::Platform.new platform
       if @new_platform.is_a?(Gem::Platform::Wheel)
-        # Wheel platforms require RubyGems 4.0+ for proper support
-        self.required_rubygems_version = ">= 4.0.0" if required_rubygems_version == Gem::Requirement.default
+        # Wheel platforms require RubyGems 3.8+ for proper support
+        self.required_rubygems_version = ">= 3.8.0.dev" if required_rubygems_version == Gem::Requirement.default
       end
     end
 

test/rubygems/test_gem_specification.rb

@@ -4179,7 +4179,7 @@ def test_wheel_platform_sets_required_rubygems_version
 
     # Setting wheel platform string should set required_rubygems_version
     spec.platform = "whl-rb33-x86_64_linux"
-    assert_equal Gem::Requirement.new(">= 4.0.0"), spec.required_rubygems_version
+    assert_equal Gem::Requirement.new(">= 3.8.0.dev"), spec.required_rubygems_version
     assert_instance_of Gem::Platform::Wheel, spec.platform
   end
 
@@ -4190,7 +4190,7 @@ def test_wheel_platform_object_sets_required_rubygems_version
 
     # Setting wheel platform object should set required_rubygems_version
     spec.platform = wheel_platform
-    assert_equal Gem::Requirement.new(">= 4.0.0"), spec.required_rubygems_version
+    assert_equal Gem::Requirement.new(">= 3.8.0.dev"), spec.required_rubygems_version
     assert_equal wheel_platform, spec.platform
   end