[rubygems/rubygems] Fix gem pristine sometimes not resetting extensions

If `gem pristine foo` is run, and there's a default copy of foo, only
executables for it are reset. However, that was causing other copies of
`foo` to only reset executables, which is unexpected.

We should not modify `options[:only_executables]`, but respect its value
for every gem, and make sure special handling for default gems does not
leak to other gems.

https://github.com/rubygems/rubygems/commit/2c3039f1b0

lib/rubygems/commands/pristine_command.rb

@@ -137,11 +137,14 @@ extensions will be restored.
     specs.group_by(&:full_name_with_location).values.each do |grouped_specs|
       spec = grouped_specs.find {|s| !s.default_gem? } || grouped_specs.first
 
-      unless only_executables_or_plugins?
+      only_executables = options[:only_executables]
+      only_plugins = options[:only_plugins]
+
+      unless only_executables || only_plugins
         # Default gemspecs include changes provided by ruby-core installer that
         # can't currently be pristined (inclusion of compiled extension targets in
         # the file list). So stick to resetting executables if it's a default gem.
-        options[:only_executables] = true if spec.default_gem?
+        only_executables = true if spec.default_gem?
       end
 
       if options.key? :skip
@@ -151,14 +154,14 @@ extensions will be restored.
         end
       end
 
-      unless spec.extensions.empty? || options[:extensions] || only_executables_or_plugins?
+      unless spec.extensions.empty? || options[:extensions] || only_executables || only_plugins
         say "Skipped #{spec.full_name_with_location}, it needs to compile an extension"
         next
       end
 
       gem = spec.cache_file
 
-      unless File.exist?(gem) || only_executables_or_plugins?
+      unless File.exist?(gem) || only_executables || only_plugins
         require_relative "../remote_fetcher"
 
         say "Cached gem for #{spec.full_name_with_location} not found, attempting to fetch..."
@@ -194,10 +197,10 @@ extensions will be restored.
         bin_dir: bin_dir,
       }
 
-      if options[:only_executables]
+      if only_executables
         installer = Gem::Installer.for_spec(spec, installer_options)
         installer.generate_bin
-      elsif options[:only_plugins]
+      elsif only_plugins
         installer = Gem::Installer.for_spec(spec, installer_options)
         installer.generate_plugins
       else
@@ -208,10 +211,4 @@ extensions will be restored.
       say "Restored #{spec.full_name_with_location}"
     end
   end
-
-  private
-
-  def only_executables_or_plugins?
-    options[:only_executables] || options[:only_plugins]
-  end
 end

test/rubygems/test_gem_commands_pristine_command.rb

@@ -659,6 +659,42 @@ class TestGemCommandsPristineCommand < Gem::TestCase
     refute_includes "ruby_executable_hooks", File.read(exe)
   end
 
+  def test_execute_default_gem_and_regular_gem
+    a_default = new_default_spec("a", "1.2.0")
+
+    a = util_spec "a" do |s|
+      s.extensions << "ext/a/extconf.rb"
+    end
+
+    ext_path = File.join @tempdir, "ext", "a", "extconf.rb"
+    write_file ext_path do |io|
+      io.write <<-'RUBY'
+      File.open "Makefile", "w" do |f|
+        f.puts "clean:\n\techo cleaned\n"
+        f.puts "all:\n\techo built\n"
+        f.puts "install:\n\techo installed\n"
+      end
+      RUBY
+    end
+
+    install_default_gems a_default
+    install_gem a
+
+    # Remove the extension files for a
+    FileUtils.rm_rf a.gem_build_complete_path
+
+    @cmd.options[:args] = %w[a]
+
+    use_ui @ui do
+      @cmd.execute
+    end
+
+    assert_includes @ui.output, "Restored #{a.full_name}"
+
+    # Check extension files for a were restored
+    assert_path_exist a.gem_build_complete_path
+  end
+
   def test_execute_multi_platform
     a = util_spec "a" do |s|
       s.extensions << "ext/a/extconf.rb"