Fix copying virtual columns when altering a table in sqlite3

Author: fatkodima

activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb

@@ -578,12 +578,6 @@ def copy_table(from, to, options = {})
                  options[:rename][column.name.to_sym] ||
                  column.name) : column.name
 
-              if column.has_default?
-                type = lookup_cast_type_from_column(column)
-                default = type.deserialize(column.default)
-                default = -> { column.default_function } if default.nil?
-              end
-
               column_options = {
                 limit: column.limit,
                 precision: column.precision,
@@ -593,19 +587,31 @@ def copy_table(from, to, options = {})
                 primary_key: column_name == from_primary_key
               }
 
-              unless column.auto_increment?
-                column_options[:default] = default
+              if column.virtual?
+                column_options[:as] = column.default_function
+                column_options[:stored] = column.virtual_stored?
+                column_options[:type] = column.type
+              elsif column.has_default?
+                type = lookup_cast_type_from_column(column)
+                default = type.deserialize(column.default)
+                default = -> { column.default_function } if default.nil?
+
+                unless column.auto_increment?
+                  column_options[:default] = default
+                end
               end
 
-              column_type = column.bigint? ? :bigint : column.type
+              column_type = column.virtual? ? :virtual : (column.bigint? ? :bigint : column.type)
               @definition.column(column_name, column_type, **column_options)
             end
 
             yield @definition if block_given?
           end
           copy_table_indexes(from, to, options[:rename] || {})
+
+          columns_to_copy = @definition.columns.reject { |col| col.options.key?(:as) }.map(&:name)
           copy_table_contents(from, to,
-            @definition.columns.map(&:name),
+            columns_to_copy,
             options[:rename] || {})
         end
 

activerecord/test/cases/adapters/sqlite3/copy_table_test.rb

@@ -85,6 +85,20 @@ def test_copy_table_with_binary_column
     test_copy_table "binaries", "binaries2"
   end
 
+  def test_copy_table_with_virtual_column
+    @connection.create_table :virtual_columns, force: true do |t|
+      t.string  :name
+      t.virtual :upper_name, type: :string, as: "UPPER(name)", stored: true
+    end
+
+    test_copy_table("virtual_columns", "virtual_columns2") do
+      column = @connection.columns("virtual_columns2").find { |col| col.name == "upper_name" }
+      assert_predicate column, :virtual_stored?
+      assert_equal :string, column.type
+      assert_equal "UPPER(name)", column.default_function
+    end
+  end
+
 private
   def copy_table(from, to, options = {})
     @connection.send(:copy_table, from, to, { temporary: true }.merge(options))