1 files changed, 35 insertions, 0 deletions
diff --git a/rubocop/cop/migration/reversible_add_column_with_default.rb b/rubocop/cop/migration/reversible_add_column_with_default.rb
new file mode 100644
index 00000000000..f413f06f39b
--- /dev/null
+++ b/rubocop/cop/migration/reversible_add_column_with_default.rb
@@ -0,0 +1,35 @@
+require_relative '../../migration_helpers'
+
+module RuboCop
+  module Cop
+    module Migration
+      # Cop that checks if `add_column_with_default` is used with `up`/`down` methods
+      # and not `change`.
+      class ReversibleAddColumnWithDefault < RuboCop::Cop::Cop
+        include MigrationHelpers
+
+        def_node_matcher :add_column_with_default?, <<~PATTERN
+          (send nil :add_column_with_default $...)
+        PATTERN
+
+        def_node_matcher :defines_change?, <<~PATTERN
+          (def :change ...)
+        PATTERN
+
+        MSG = '`add_column_with_default` is not reversible so you must manually define ' \
+          'the `up` and `down` methods in your migration class, using `remove_column` in `down`'.freeze
+
+        def on_send(node)
+          return unless in_migration?(node)
+          return unless add_column_with_default?(node)
+
+          node.each_ancestor(:def) do |def_node|
+            next unless defines_change?(def_node)
+
+            add_offense(def_node, :name)
+          end
+        end
+      end
+    end
+  end
+end