1 files changed, 143 insertions, 0 deletions
diff --git a/spec/rubocop/cop/migration/prevent_strings_spec.rb b/spec/rubocop/cop/migration/prevent_strings_spec.rb
new file mode 100644
index 00000000000..2702ce1c090
--- /dev/null
+++ b/spec/rubocop/cop/migration/prevent_strings_spec.rb
@@ -0,0 +1,143 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+require 'rubocop'
+require 'rubocop/rspec/support'
+
+require_relative '../../../../rubocop/cop/migration/prevent_strings'
+
+describe RuboCop::Cop::Migration::PreventStrings do
+  include CopHelper
+
+  subject(:cop) { described_class.new }
+
+  context 'in migration' do
+    before do
+      allow(cop).to receive(:in_migration?).and_return(true)
+    end
+
+    context 'when the string data type is used' do
+      it 'registers an offense' do
+        expect_offense(<<~RUBY)
+          class Users < ActiveRecord::Migration[6.0]
+            DOWNTIME = false
+
+            def up
+              create_table :users do |t|
+                t.string :username, null: false
+                  ^^^^^^ #{described_class::MSG}
+
+                t.timestamps_with_timezone null: true
+
+                t.string :password
+                  ^^^^^^ #{described_class::MSG}
+              end
+
+              add_column(:users, :bio, :string)
+              ^^^^^^^^^^ #{described_class::MSG}
+
+              add_column_with_default(:users, :url, :string, default: '/-/user', allow_null: false, limit: 255)
+              ^^^^^^^^^^^^^^^^^^^^^^^ #{described_class::MSG}
+
+              change_column_type_concurrently :users, :commit_id, :string
+              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ #{described_class::MSG}
+            end
+          end
+        RUBY
+
+        expect(cop.offenses.map(&:cop_name)).to all(eq('Migration/PreventStrings'))
+      end
+    end
+
+    context 'when the string data type is not used' do
+      it 'registers no offense' do
+        expect_no_offenses(<<~RUBY)
+          class Users < ActiveRecord::Migration[6.0]
+            DOWNTIME = false
+
+            def up
+              create_table :users do |t|
+                t.integer :not_a_string, null: false
+                t.timestamps_with_timezone null: true
+              end
+
+              add_column(:users, :not_a_string, :integer)
+            end
+          end
+        RUBY
+      end
+    end
+
+    context 'when the text data type is used' do
+      it 'registers no offense' do
+        expect_no_offenses(<<~RUBY)
+          class Users < ActiveRecord::Migration[6.0]
+            DOWNTIME = false
+
+            def up
+              create_table :users do |t|
+                t.text :username, null: false
+                t.timestamps_with_timezone null: true
+                t.text :password
+              end
+
+              add_column(:users, :bio, :text)
+              add_column_with_default(:users, :url, :text, default: '/-/user', allow_null: false, limit: 255)
+              change_column_type_concurrently :users, :commit_id, :text
+            end
+          end
+        RUBY
+      end
+    end
+
+    context 'on down' do
+      it 'registers no offense' do
+        expect_no_offenses(<<~RUBY)
+          class Users < ActiveRecord::Migration[6.0]
+            DOWNTIME = false
+
+            def up
+              remove_column :users, :bio
+              remove_column :users, :url
+
+              drop_table :test_strings
+            end
+
+            def down
+              create_table :test_strings, id: false do |t|
+                t.integer :test_id, null: false
+                t.string :name
+              end
+
+              add_column(:users, :bio, :string)
+              add_column_with_default(:users, :url, :string, default: '/-/user', allow_null: false, limit: 255)
+              change_column_type_concurrently :users, :commit_id, :string
+            end
+          end
+        RUBY
+      end
+    end
+  end
+
+  context 'outside of migration' do
+    it 'registers no offense' do
+      expect_no_offenses(<<~RUBY)
+        class Users < ActiveRecord::Migration[6.0]
+          DOWNTIME = false
+
+          def up
+            create_table :users do |t|
+              t.string :username, null: false
+              t.timestamps_with_timezone null: true
+              t.string :password
+            end
+
+            add_column(:users, :bio, :string)
+            add_column_with_default(:users, :url, :string, default: '/-/user', allow_null: false, limit: 255)
+            change_column_type_concurrently :users, :commit_id, :string
+          end
+        end
+      RUBY
+    end
+  end
+end