1 files changed, 20 insertions, 0 deletions
diff --git a/rubocop/cop/database/establish_connection.rb b/rubocop/cop/database/establish_connection.rb
new file mode 100644
index 00000000000..20454887ce2
--- /dev/null
+++ b/rubocop/cop/database/establish_connection.rb
@@ -0,0 +1,20 @@
+# frozen_string_literal: true
+
+module RuboCop
+  module Cop
+    module Database
+      class EstablishConnection < RuboCop::Cop::Cop
+        MSG = "Don't establish new database connections, as this slows down " \
+          'tests and may result in new connections using an incorrect configuration'
+
+        def_node_matcher :establish_connection?, <<~PATTERN
+          (send (const ...) :establish_connection ...)
+        PATTERN
+
+        def on_send(node)
+          add_offense(node, location: :expression) if establish_connection?(node)
+        end
+      end
+    end
+  end
+end