From 951eb7ea94c2c2e3b4776291cdb41ab4e6d8943b Mon Sep 17 00:00:00 2001
From: Kaoru Shirai <475350+kaorukobo@users.noreply.github.com>
Date: Tue, 20 Feb 2024 14:52:54 +0900
Subject: [PATCH] Avoid accidental replacement of main DB model connections

---
 lib/database_cleaner/active_record/base.rb       | 7 +++++--
 spec/database_cleaner/active_record/base_spec.rb | 3 ++-
 2 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/lib/database_cleaner/active_record/base.rb b/lib/database_cleaner/active_record/base.rb
index ed61045f..51a3e341 100644
--- a/lib/database_cleaner/active_record/base.rb
+++ b/lib/database_cleaner/active_record/base.rb
@@ -84,8 +84,11 @@ def lookup_from_connection_pool
       end
 
       def establish_connection
-        ::ActiveRecord::Base.establish_connection(connection_hash)
-        ::ActiveRecord::Base
+        # creates a temporary ActiveRecord class that is unique to connection_hash
+        ActiveRecord.module_eval("class Temp#{connection_hash.hash.abs} < ::ActiveRecord::Base; self; end")
+          .tap { |ar_class|
+            ar_class.establish_connection(connection_hash)
+          }
       end
 
       def database_for(model)
diff --git a/spec/database_cleaner/active_record/base_spec.rb b/spec/database_cleaner/active_record/base_spec.rb
index 652ca9cd..73efdee8 100644
--- a/spec/database_cleaner/active_record/base_spec.rb
+++ b/spec/database_cleaner/active_record/base_spec.rb
@@ -166,7 +166,8 @@ module ActiveRecord
 
             it "establishes a connection with it" do
               expect(::ActiveRecord::Base).to receive(:establish_connection).with(hash)
-              expect(strategy.connection_class).to eq ::ActiveRecord::Base
+              expect(strategy.connection_class).to be < ::ActiveRecord::Base
+              expect(strategy.connection_class.name).to match /^DatabaseCleaner::ActiveRecord::Temp\d+$/
             end
           end