Migration helper module

config/default.yml

@@ -16,8 +16,8 @@ Sequel/IrreversibleMigration:
     Warns against using certain methods inside a migration file's `change` block that would cause the migration to become irreversible.
   Reference: https://www.rubydoc.info/gems/rubocop-sequel/RuboCop/Cop/Sequel/IrreversibleMigration
   Enabled: true
-  VersionAdded: 0.3.4
-  VersionChanged: 0.3.4
+  VersionAdded: 0.3.5
+  VersionChanged: 0.3.6
 
 Sequel/JSONColumn:
   Description: >-
@@ -52,3 +52,9 @@ Sequel/SaveChanges:
   SafeAutoCorrect: false
   VersionAdded: '0.0.1'
   VersionChanged: '0.3.3'
+
+Sequel/Helpers/Migration:
+  Description: Contains helper methods for detecting if a node is inside a `Sequel.migration` block
+  Reference: https://www.rubydoc.info/gems/rubocop-sequel/RuboCop/Cop/Sequel/Helpers/Migration
+  VersionAdded: 0.3.6
+  VersionChanged: 0.3.6

lib/rubocop-sequel.rb

@@ -7,6 +7,8 @@
 
 RuboCop::Sequel::Inject.defaults!
 
+require 'rubocop/cop/sequel/helpers/migration'
+
 require 'rubocop/cop/sequel/concurrent_index'
 require 'rubocop/cop/sequel/irreversible_migration'
 require 'rubocop/cop/sequel/json_column'

lib/rubocop/cop/sequel/helpers/migration.rb

@@ -0,0 +1,25 @@
+# frozen_string_literal: true
+
+module RuboCop
+  module Cop
+    module Sequel
+      module Helpers
+        # Migration contains helper methods for detecting if a node is inside a `Sequel.migration` block
+        module Migration
+          extend NodePattern::Macros
+
+          def_node_matcher :sequel_migration_block?, <<~MATCHER
+            (block
+              (send
+                (const nil? :Sequel) :migration ...)
+              ...)
+          MATCHER
+
+          def within_sequel_migration?(node)
+            node.each_ancestor(:block).any? { |ancestor| sequel_migration_block?(ancestor) }
+          end
+        end
+      end
+    end
+  end
+end

lib/rubocop/cop/sequel/irreversible_migration.rb

@@ -5,6 +5,8 @@ module Cop
     module Sequel
       # IrreversibleMigration looks for methods inside a `change` block that cannot be reversed.
       class IrreversibleMigration < Base
+        include RuboCop::Cop::Sequel::Helpers::Migration
+
         # https://sequel.jeremyevans.net/rdoc/files/doc/migration_rdoc.html#label-A+Basic+Migration
         VALID_CHANGE_METHODS = %i[
           create_table
@@ -26,11 +28,12 @@ class IrreversibleMigration < Base
           set_column_allow_null
         ].freeze
 
-        MSG = 'Avoid using `%<name>s` inside a `change` block. Use `up` & `down` blocks instead.'
-        PRIMARY_KEY_MSG = 'Avoid using `add_primary_key` with an array argument inside a `change` block.'
+        MSG = 'Avoid using "%<name>s" inside a "change" block. Use "up" & "down" blocks instead.'
+        PRIMARY_KEY_MSG = 'Avoid using "add_primary_key" with an array argument inside a "change" block.'
 
         def on_block(node)
           return unless node.method_name == :change
+          return unless within_sequel_migration?(node)
 
           body = node.body
           return unless body

lib/rubocop/sequel/version.rb

@@ -4,7 +4,7 @@ module RuboCop
   module Sequel
     # This module holds the RuboCop Sequel version information.
     module Version
-      STRING = '0.3.5'
+      STRING = '0.3.6'
     end
   end
 end

rubocop-sequel.gemspec

@@ -12,7 +12,7 @@ Gem::Specification.new do |gem|
   gem.executables   = gem.files.grep(%r{^bin/}).map { |f| File.basename(f) }
   gem.name          = 'rubocop-sequel'
   gem.require_paths = ['lib']
-  gem.version       = '0.3.5'
+  gem.version       = '0.3.6'
   gem.metadata['rubygems_mfa_required'] = 'true'
 
   gem.required_ruby_version = '>= 2.5'

spec/rubocop/cop/sequel/irreversible_migration_spec.rb

@@ -6,22 +6,26 @@
   context 'when inside a change block' do
     let(:invalid_source) do
       <<~SOURCE
-        change do
-          alter_table(:stores) do
-            drop_column(:products, :name)
-            drop_index(:products, :price)
+        Sequel.migration do
+          change do
+            alter_table(:stores) do
+              drop_column(:products, :name)
+              drop_index(:products, :price)
+            end
           end
         end
       SOURCE
     end
 
     let(:valid_source) do
       <<~SOURCE
-        change do
-          alter_table(:stores) do
-            add_primary_key(:id)
-            add_column(:products, :name)
-            add_index(:products, :price)
+        Sequel.migration do
+          change do
+            alter_table(:stores) do
+              add_primary_key(:id)
+              add_column(:products, :name)
+              add_index(:products, :price)
+            end
           end
         end
       SOURCE
@@ -40,9 +44,11 @@
     describe 'and an array is passed into `add_primary_key`' do
       let(:source) do
         <<~SOURCE
-          change do
-            alter_table(:stores) do
-              add_primary_key([:owner_id, :name])
+          Sequel.migration do
+            change do
+              alter_table(:stores) do
+                add_primary_key([:owner_id, :name])
+              end
             end
           end
         SOURCE
@@ -58,11 +64,13 @@
   context 'when inside an up block' do
     let(:source) do
       <<~SOURCE
-        up do
-          alter_table(:stores) do
-            add_primary_key([:owner_id, :name])
-            add_column(:products, :name)
-            drop_index(:products, :price)
+        Sequel.migration do
+          up do
+            alter_table(:stores) do
+              add_primary_key([:owner_id, :name])
+              add_column(:products, :name)
+              drop_index(:products, :price)
+            end
           end
         end
       SOURCE
@@ -73,4 +81,17 @@
       expect(offenses).to be_empty
     end
   end
+
+  context 'when a change block is used outside of a Sequel migration' do
+    let(:source) do
+      <<~SOURCE
+        it { expect { subject }.to change { document_count(user_id) }.by(-1) }
+      SOURCE
+    end
+
+    it 'does not register an offense with any methods' do
+      offenses = inspect_source(source)
+      expect(offenses).to be_empty
+    end
+  end
 end