[rubygems/rubygems] Don't re-resolve with prereleases if unlocked gem has no prereleases

https://github.com/rubygems/rubygems/commit/d76dc70d90

lib/bundler/resolver.rb

@@ -131,7 +131,7 @@ module Bundler
 
           if base_requirements[name]
             names_to_unlock << name
-          elsif package.ignores_prereleases?
+          elsif package.ignores_prereleases? && @all_specs[name].any? {|s| s.version.prerelease? }
             names_to_allow_prereleases_for << name
           end
 

spec/bundler/realworld/edgecases_spec.rb

@@ -323,7 +323,7 @@ RSpec.describe "real world edgecases", :realworld => true do
     if Bundler.feature_flag.bundler_3_mode?
       # Conflicts on bundler version, so we count attempts differently
       bundle :lock, :env => { "DEBUG_RESOLVER" => "1" }, :raise_on_error => false
-      expect(out.split("\n").grep(/backtracking to/).count).to eq(16)
+      expect(out.split("\n").grep(/backtracking to/).count).to eq(8)
     else
       bundle :lock, :env => { "DEBUG_RESOLVER" => "1" }
       expect(out).to include("Solution found after 7 attempts")

spec/bundler/resolver/basic_spec.rb

@@ -107,6 +107,15 @@ RSpec.describe "Resolving" do
     end.to raise_error(Bundler::SolveFailure)
   end
 
+  it "does not try to re-resolve including prereleases if gems involved don't have prereleases" do
+    @index = a_unresolvable_child_index
+    dep "chef_app_error"
+    expect(Bundler.ui).not_to receive(:debug).with("Retrying resolution...", any_args)
+    expect do
+      resolve
+    end.to raise_error(Bundler::SolveFailure)
+  end
+
   it "raises an exception with the minimal set of conflicting dependencies" do
     @index = build_index do
       %w[0.9 1.0 2.0].each {|v| gem("a", v) }