AR has a subclass of AM:PresenceValidator.

This allows us to mark the parent object as invalid if all associated objects
in a presence validated association are marked for destruction.

See: https://github.com/rails/rails/issues/6812

1 files changed, 44 insertions, 0 deletions

diff --git a/activerecord/test/cases/validations/presence_validation_test.rb b/activerecord/test/cases/validations/presence_validation_test.rb
new file mode 100644
index 0000000000..cd9175f454
--- /dev/null
+++ b/activerecord/test/cases/validations/presence_validation_test.rb
@@ -0,0 +1,44 @@
+# encoding: utf-8
+require "cases/helper"
+require 'models/man'
+require 'models/face'
+require 'models/interest'
+
+class PresenceValidationTest < ActiveRecord::TestCase
+  class Boy < Man; end
+
+  repair_validations(Boy)
+
+  def test_validates_presence_of_non_association
+    Boy.validates_presence_of(:name)
+    b = Boy.new
+    assert b.invalid?
+
+    b.name = "Alex"
+    assert b.valid?
+  end
+
+  def test_validates_presence_of_has_one_marked_for_destruction
+    Boy.validates_presence_of(:face)
+    b = Boy.new
+    f = Face.new
+    b.face = f
+    assert b.valid?
+
+    f.mark_for_destruction
+    assert b.invalid?
+  end
+
+  def test_validates_presence_of_has_many_marked_for_destruction
+    Boy.validates_presence_of(:interests)
+    b = Boy.new
+    b.interests << [i1 = Interest.new, i2 = Interest.new]
+    assert b.valid?
+
+    i1.mark_for_destruction
+    assert b.valid?
+
+    i2.mark_for_destruction
+    assert b.invalid?
+  end
+end