Stub use_foreign_keys? instead of swapping the connection pool in specs

The previous spec re-established ActiveRecord::Base with
foreign_keys: false in before(:each) and restored CONNECTION_PARAMS in
after(:each). That swaps the global pool, so the outer describe's
before(:all)-captured @conn ends up pointing at a connection from the
discarded pool. A later spec (schema_dumper_spec.rb:571 "should specify
non-default tablespace in add index") then stubs default_tablespace on
that stale @conn, while SchemaDumper queries the fresh pool's
connection. The stub never takes effect, the index dump lacks the
tablespace, and the example fails under randomized ordering.

Stub @conn.use_foreign_keys? on the live connection instead. That keeps
the pool intact, avoids cross-describe state leakage, and still
exercises every oracle-enhanced gate (add_foreign_key early return,
SchemaCreation FK skip, SchemaDumper FK skip). The
foreign_keys: false → use_foreign_keys? == false plumbing is Rails
core's responsibility (foreign_keys_enabled? = @config.fetch(...))
and is already covered upstream.

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

Author: yahonda

spec/active_record/connection_adapters/oracle_enhanced/schema_dumper_spec.rb

@@ -440,11 +440,8 @@ def drop_test_posts_table
     end
   end
 
-  describe "foreign_keys: false database.yml option" do
-    let(:foreign_keys_disabled_conn) { ActiveRecord::Base.lease_connection }
-
+  describe "with use_foreign_keys? returning false (foreign_keys: false in database.yml)" do
     before(:each) do
-      ActiveRecord::Base.establish_connection(CONNECTION_PARAMS.merge(foreign_keys: false))
       schema_define do
         drop_table :test_comments, if_exists: true
         drop_table :test_posts, if_exists: true
@@ -460,52 +457,50 @@ def drop_test_posts_table
 
     after(:each) do
       schema_define do
+        remove_foreign_key :test_comments, :test_posts, if_exists: true
         drop_table :test_comments, if_exists: true
         drop_table :test_posts, if_exists: true
       end
-    ensure
-      ActiveRecord::Base.establish_connection(CONNECTION_PARAMS)
-    end
-
-    it "reports use_foreign_keys? as false" do
-      expect(foreign_keys_disabled_conn.use_foreign_keys?).to be false
-      expect(foreign_keys_disabled_conn.supports_foreign_keys?).to be true
     end
 
     it "schema dump omits add_foreign_key statements" do
       schema_define do
         add_foreign_key :test_comments, :test_posts
       end
+      allow(@conn).to receive(:use_foreign_keys?).and_return(false)
       expect(standard_dump).not_to match(/add_foreign_key/)
     end
 
     it "add_foreign_key is a silent no-op" do
+      allow(@conn).to receive(:use_foreign_keys?).and_return(false)
       expect {
         schema_define do
           add_foreign_key :test_comments, :test_posts
         end
       }.not_to raise_error
-      expect(foreign_keys_disabled_conn.foreign_keys("test_comments")).to be_empty
+      expect(@conn.foreign_keys("test_comments")).to be_empty
     end
 
-    it "add_foreign_key skips deferrable validation when disabled" do
+    it "add_foreign_key skips deferrable validation" do
+      allow(@conn).to receive(:use_foreign_keys?).and_return(false)
       expect {
         schema_define do
           add_foreign_key :test_comments, :test_posts, deferrable: :always
         end
       }.not_to raise_error
-      expect(foreign_keys_disabled_conn.foreign_keys("test_comments")).to be_empty
+      expect(@conn.foreign_keys("test_comments")).to be_empty
     end
 
     it "create_table with inline t.references foreign_key: true does not create the FK" do
+      allow(@conn).to receive(:use_foreign_keys?).and_return(false)
       schema_define do
         drop_table :test_comments, if_exists: true
         create_table :test_comments, force: true do |t|
           t.string :body, limit: 4000
           t.references :test_post, foreign_key: true
         end
       end
-      expect(foreign_keys_disabled_conn.foreign_keys("test_comments")).to be_empty
+      expect(@conn.foreign_keys("test_comments")).to be_empty
     end
   end