Add ignore_rubygems_upper_bounds setting

Same approach as ignore_ruby_upper_bounds but for required_rubygems_version
constraints. The metadata_dependency method now checks both settings
independently, and matches_current_rubygems? also respects the setting
for install-time compatibility checks.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: hsbt

bundler/lib/bundler/man/bundle-config.1

@@ -142,6 +142,12 @@ When set, no funding requests will be printed\.
 \fBignore_messages\fR (\fBBUNDLE_IGNORE_MESSAGES\fR)
 When set, no post install messages will be printed\. To silence a single gem, use dot notation like \fBignore_messages\.httparty true\fR\.
 .TP
+\fBignore_ruby_upper_bounds\fR (\fBBUNDLE_IGNORE_RUBY_UPPER_BOUNDS\fR)
+When set, Bundler ignores upper bound constraints (\fB<\fR and \fB<=\fR) on \fBrequired_ruby_version\fR in gem metadata\. Useful when gems haven't updated their gemspecs for newer Ruby versions but still work fine\.
+.TP
+\fBignore_rubygems_upper_bounds\fR (\fBBUNDLE_IGNORE_RUBYGEMS_UPPER_BOUNDS\fR)
+When set, Bundler ignores upper bound constraints (\fB<\fR and \fB<=\fR) on \fBrequired_rubygems_version\fR in gem metadata\. Useful when gems haven't updated their gemspecs for newer RubyGems versions but still work fine\.
+.TP
 \fBinit_gems_rb\fR (\fBBUNDLE_INIT_GEMS_RB\fR)
 Generate a \fBgems\.rb\fR instead of a \fBGemfile\fR when running \fBbundle init\fR\.
 .TP

bundler/lib/bundler/man/bundle-config.1.ronn

@@ -189,6 +189,14 @@ learn more about their operation in [bundle install(1)](bundle-install.1.html).
 * `ignore_messages` (`BUNDLE_IGNORE_MESSAGES`):
    When set, no post install messages will be printed. To silence a single gem,
    use dot notation like `ignore_messages.httparty true`.
+* `ignore_ruby_upper_bounds` (`BUNDLE_IGNORE_RUBY_UPPER_BOUNDS`):
+   When set, Bundler ignores upper bound constraints (`<` and `<=`) on
+   `required_ruby_version` in gem metadata. Useful when gems haven't updated
+   their gemspecs for newer Ruby versions but still work fine.
+* `ignore_rubygems_upper_bounds` (`BUNDLE_IGNORE_RUBYGEMS_UPPER_BOUNDS`):
+   When set, Bundler ignores upper bound constraints (`<` and `<=`) on
+   `required_rubygems_version` in gem metadata. Useful when gems haven't
+   updated their gemspecs for newer RubyGems versions but still work fine.
 * `init_gems_rb` (`BUNDLE_INIT_GEMS_RB`):
    Generate a `gems.rb` instead of a `Gemfile` when running `bundle init`.
 * `jobs` (`BUNDLE_JOBS`):

bundler/lib/bundler/match_metadata.rb

@@ -16,7 +16,12 @@ def matches_current_ruby?
     end
 
     def matches_current_rubygems?
-      @required_rubygems_version.satisfied_by?(Gem.rubygems_version)
+      requirement = if Bundler.settings[:ignore_rubygems_upper_bounds]
+        remove_upper_bounds(@required_rubygems_version)
+      else
+        @required_rubygems_version
+      end
+      requirement.satisfied_by?(Gem.rubygems_version)
     end
 
     def expanded_dependencies
@@ -29,7 +34,8 @@ def expanded_dependencies
     def metadata_dependency(name, requirement)
       return if requirement.nil? || requirement.none?
 
-      if name == "Ruby" && Bundler.settings[:ignore_ruby_upper_bounds]
+      if (name == "Ruby" && Bundler.settings[:ignore_ruby_upper_bounds]) ||
+         (name == "RubyGems" && Bundler.settings[:ignore_rubygems_upper_bounds])
         requirement = remove_upper_bounds(requirement)
         return if requirement.none?
       end
@@ -40,7 +46,7 @@ def metadata_dependency(name, requirement)
     private
 
     def remove_upper_bounds(requirement)
-      filtered = requirement.requirements.reject {|op, _| op == "<" || op == "<=" }
+      filtered = requirement.requirements.reject {|op, _| ["<", "<="].include?(op) }
       if filtered.empty?
         Gem::Requirement.default
       else

bundler/lib/bundler/settings.rb

@@ -28,6 +28,7 @@ class Settings
       global_gem_cache
       ignore_messages
       ignore_ruby_upper_bounds
+      ignore_rubygems_upper_bounds
       init_gems_rb
       inline
       lockfile_checksums

spec/bundler/match_metadata_spec.rb

@@ -56,6 +56,32 @@ def initialize(ruby_version, rubygems_version)
     end
   end
 
+  describe "#matches_current_rubygems?" do
+    context "when the rubygems version has an upper bound that excludes the current rubygems" do
+      let(:spec) { klass.new(Gem::Requirement.default, Gem::Requirement.new(">= 3.0", "< 3.1")) }
+
+      it "returns false by default" do
+        expect(spec.matches_current_rubygems?).to be false
+      end
+
+      it "returns true when ignore_rubygems_upper_bounds is set" do
+        bundle "config set ignore_rubygems_upper_bounds true"
+        expect(spec.matches_current_rubygems?).to be true
+      end
+    end
+
+    context "when the rubygems version has only a lower bound" do
+      let(:spec) { klass.new(Gem::Requirement.default, Gem::Requirement.new(">= 2.0")) }
+
+      it "returns true regardless of setting" do
+        expect(spec.matches_current_rubygems?).to be true
+
+        bundle "config set ignore_rubygems_upper_bounds true"
+        expect(spec.matches_current_rubygems?).to be true
+      end
+    end
+  end
+
   describe "#metadata_dependency" do
     context "when ignore_ruby_upper_bounds is set" do
       before { bundle "config set ignore_ruby_upper_bounds true" }
@@ -78,5 +104,21 @@ def initialize(ruby_version, rubygems_version)
         expect(dep.requirement).to eq(Gem::Requirement.new(">= 3.0", "< 4.0"))
       end
     end
+
+    context "when ignore_rubygems_upper_bounds is set" do
+      before { bundle "config set ignore_rubygems_upper_bounds true" }
+
+      it "removes upper bounds from RubyGems dependency" do
+        spec = klass.new(Gem::Requirement.default, Gem::Requirement.new(">= 3.0", "< 4.0"))
+        dep = spec.send(:metadata_dependency, "RubyGems", spec.required_rubygems_version)
+        expect(dep.requirement).to eq(Gem::Requirement.new(">= 3.0"))
+      end
+
+      it "does not affect Ruby dependency" do
+        spec = klass.new(Gem::Requirement.new(">= 3.0", "< 3.1"), Gem::Requirement.default)
+        dep = spec.send(:metadata_dependency, "Ruby", spec.required_ruby_version)
+        expect(dep.requirement).to eq(Gem::Requirement.new(">= 3.0", "< 3.1"))
+      end
+    end
   end
 end