[ruby/rubygems] Stop blanket-unlocking the lockfile on :all overrides

Previously, any :all override called unlock_all_locked_specs_for_override
which pushed every locked spec into @gems_to_unlock. A user adding a
narrow `override :all, required_ruby_version: :ignore_upper` thus paid
for a full re-resolve that could pull unrelated dependency
upgrades/downgrades.

Make :all overrides leave the lockfile alone at converge time. They
take effect on a fresh resolution (no lockfile) or when the user opts
in via `bundle update`. Per-gem overrides retain their unlock for the
named gem since the user explicitly named the target.

https://github.com/ruby/rubygems/commit/3c95ab99e3

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

2 files changed, 11 insertions, 15 deletions

diff --git a/lib/bundler/definition.rb b/lib/bundler/definition.rb
index 2fe28f7656..2aa74804ba 100644
--- a/lib/bundler/definition.rb
+++ b/lib/bundler/definition.rb
@@ -1061,11 +1061,10 @@ module Bundler
 
     def converge_overrides_outside_dependencies
       @overrides.each do |override|
-        if override.target == :all
-          unlock_all_locked_specs_for_override
-          next
-        end
-
+        # :all overrides are intentionally not pre-unlocked. They take effect on
+        # fresh resolution (no lockfile) or when the user runs `bundle update`.
+        # Forcing a full re-resolve from a single :all directive would surprise
+        # users with unrelated dependency churn.
         next unless override.target.is_a?(String)
 
         name = override.target
@@ -1081,15 +1080,6 @@ module Bundler
       end
     end
 
-    def unlock_all_locked_specs_for_override
-      @originally_locked_specs.each do |locked_spec|
-        name = locked_spec.name
-        next if @changed_dependencies.include?(name)
-        @gems_to_unlock << name
-        @changed_dependencies << name
-      end
-    end
-
     # Remove elements from the locked specs that are expired. This will most
     # commonly happen if the Gemfile has changed since the lockfile was last
     # generated
diff --git a/spec/bundler/install/gemfile/override_spec.rb b/spec/bundler/install/gemfile/override_spec.rb
index 19fa2ee915..02b0e7d772 100644
--- a/spec/bundler/install/gemfile/override_spec.rb
+++ b/spec/bundler/install/gemfile/override_spec.rb
@@ -291,7 +291,7 @@ RSpec.describe "override DSL" do
       expect(err).to include("still_blocked")
     end
 
-    it "re-resolves a previously locked spec when an :all metadata override is added" do
+    it "preserves locked versions when an :all metadata override is added without bundle update" do
       build_repo2 do
         build_gem "selectable", "1.0"
         build_gem "selectable", "2.0" do |s|
@@ -313,7 +313,13 @@ RSpec.describe "override DSL" do
         gem "selectable"
       G
 
+      # :all override alone does not pre-unlock locked specs; narrow change
+      # should not trigger unrelated lockfile churn.
       bundle :lock
+      expect(lockfile).to include("selectable (1.0)")
+
+      # bundle update opts the user into re-resolution under the override.
+      bundle "update selectable"
       expect(lockfile).to include("selectable (2.0)")
     end
   end