avoid column.default type_cast-ing on AR 4.2 - been causing some nesty bugs

... e.g. on postres as an array 'default' instance has been leaking into models

Author: kares

lib/arjdbc/jdbc/column.rb

@@ -26,7 +26,6 @@ def initialize(config, name, *args)
           end
         end
         default = default_value(default)
-        default = args[0].type_cast_from_database(default) if ArJdbc::AR42
 
         # super <= 4.1: (name, default, sql_type = nil, null = true)
         # super >= 4.2: (name, default, cast_type, sql_type = nil, null = true)

test/db/postgresql/column_test.rb

@@ -1,6 +1,64 @@
 require 'db/postgres'
 require 'change_column_test_methods'
 
-class PostgreSQLChangeColumnTest < Test::Unit::TestCase
+class PostgreSQLColumnTest < Test::Unit::TestCase
   include ChangeColumnTestMethods
-end
+end
+
+class PostgreSQLColumnDefaultTest < Test::Unit::TestCase
+
+  class Project < ActiveRecord::Base; end
+
+  def setup
+    @connection = ActiveRecord::Base.connection
+    @connection.transaction do
+      @connection.create_table 'projects', force: :cascade do |t|
+        t.string "name", limit: 255, default: ' '
+        t.text   "some_ids", array: true, default: []
+      end
+    end
+  end
+
+  def teardown
+    @connection.execute 'DROP TABLE IF EXISTS projects'
+  end
+
+  test 'default value from column is not shared' do
+    assert_equal ' ', Project.columns_hash['name'].default
+
+    p = Project.create!
+    assert_equal ' ', p.name
+    p.name.replace '1-replaced'
+
+    p = Project.new; p.name << '2-append'; p.save!
+    assert_equal ' ', Project.columns_hash['name'].default
+
+    p = Project.new; p.name << '3-append'
+    assert_equal ' ', Project.columns_hash['name'].default
+  end
+
+  test '_ids assingment incorrect array column default (shared bug)' do
+    Project.create!(:name => 'p1', :some_ids => ['1'])
+    p = Project.new(:name => 'p2'); p.some_ids << '2'; p.save!
+
+    if ar_version('4.2')
+      assert_equal '{}', Project.columns_hash['some_ids'].default
+    else
+      assert_equal [], Project.columns_hash['some_ids'].default
+    end
+
+    assert_equal ['2'], p.some_ids
+    if ar_version('4.2')
+      assert_equal ['2'], p.reload.some_ids
+    else
+      # MRI under AR 4.1 gets messed up the same :
+      assert_equal [], p.reload.some_ids
+    end
+
+    p = Project.new(:name => 'p3')
+    assert_equal [], p.some_ids
+    p.save!
+    assert_equal [], p.some_ids
+  end
+
+end if Test::Unit::TestCase.ar_version('4.0')