Fix `AM::Errors.added?` trying to generate a message:

- When a ActiveRecord record get saved and validated as part of a
  collection association, the errors attribute are changed to reflect
  the children names. You end up with an error attribute that will
  look like this:

  `author.errors # {:'books.title' => [:blank]}`

  https://github.com/rails/rails/blob/2fe20cb55c76e6e50ec3a4ec5b03bbb65adba290/activerecord/lib/active_record/autosave_association.rb#L331-L340

  We then can't check if the `books.title` errors was added using
  `ActiveModel::Errors#added?` because it tries to generate a message
  to make the match and end up calling the "books.title" method
  on the Author.

  ```
  author.errors.added?(:'books.title', :blank) => NoMethodError: undefined method `books.title'
  ```

  This patch modify the behaviour of `strict_match?` to not generate
  a message to make the comparison but instead make a strict
  comparison with the `options` from the error.

2 files changed, 24 insertions, 2 deletions

diff --git a/activemodel/lib/active_model/error.rb b/activemodel/lib/active_model/error.rb
index f7267fc7bf..b45d432bb2 100644
--- a/activemodel/lib/active_model/error.rb
+++ b/activemodel/lib/active_model/error.rb
@@ -58,9 +58,9 @@ module ActiveModel
     end
 
     def strict_match?(attribute, type, **options)
-      return false unless match?(attribute, type, **options)
+      return false unless match?(attribute, type)
 
-      full_message == Error.new(@base, attribute, type, **options).full_message
+      options == @options.except(*CALLBACKS_OPTIONS + MESSAGE_OPTIONS)
     end
 
     def ==(other)
diff --git a/activemodel/test/cases/errors_test.rb b/activemodel/test/cases/errors_test.rb
index baaf404f2e..e7ec9225b0 100644
--- a/activemodel/test/cases/errors_test.rb
+++ b/activemodel/test/cases/errors_test.rb
@@ -274,6 +274,28 @@ class ErrorsTest < ActiveModel::TestCase
     assert_equal [msg], person.errors[:name]
   end
 
+  test "added? when attribute was added through a collection" do
+    person = Person.new
+    person.errors.add(:"family_members.name", :too_long, count: 25)
+    assert person.errors.added?(:"family_members.name", :too_long, count: 25)
+    assert_not person.errors.added?(:"family_members.name", :too_long)
+    assert_not person.errors.added?(:"family_members.name", :too_long, name: "hello")
+  end
+
+  test "added? ignores callback option" do
+    person = Person.new
+
+    person.errors.add(:name, :too_long, if: -> { true })
+    assert person.errors.added?(:name, :too_long)
+  end
+
+  test "added? ignores message option" do
+    person = Person.new
+
+    person.errors.add(:name, :too_long, message: proc { "foo" })
+    assert person.errors.added?(:name, :too_long)
+  end
+
   test "added? detects indifferent if a specific error was added to the object" do
     person = Person.new
     person.errors.add(:name, "cannot be blank")