diff options
4 files changed, 51 insertions, 3 deletions
diff --git a/activerecord/lib/active_record/associations/collection_association.rb b/activerecord/lib/active_record/associations/collection_association.rb index 840d900bbc..17f028c1a2 100644 --- a/activerecord/lib/active_record/associations/collection_association.rb +++ b/activerecord/lib/active_record/associations/collection_association.rb @@ -413,9 +413,9 @@ module ActiveRecord end def replace_records(new_target, original_target) - delete(target - new_target) + delete(difference(target, new_target)) - unless concat(new_target - target) + unless concat(difference(new_target, target)) @target = original_target raise RecordNotSaved, "Failed to replace #{reflection.name} because one or more of the " \ "new records could not be saved." @@ -425,7 +425,7 @@ module ActiveRecord end def replace_common_records_in_memory(new_target, original_target) - common_records = new_target & original_target + common_records = union(new_target, original_target) common_records.each do |record| skip_callbacks = true replace_on_target(record, @target.index(record), skip_callbacks) diff --git a/activerecord/lib/active_record/associations/has_many_association.rb b/activerecord/lib/active_record/associations/has_many_association.rb index cf85a87fa7..6beec4dea4 100644 --- a/activerecord/lib/active_record/associations/has_many_association.rb +++ b/activerecord/lib/active_record/associations/has_many_association.rb @@ -130,6 +130,14 @@ module ActiveRecord end saved_successfully end + + def difference(a, b) + a - b + end + + def union(a, b) + a & b + end end end end diff --git a/activerecord/lib/active_record/associations/has_many_through_association.rb b/activerecord/lib/active_record/associations/has_many_through_association.rb index f84ac65fa2..b30d3ddac2 100644 --- a/activerecord/lib/active_record/associations/has_many_through_association.rb +++ b/activerecord/lib/active_record/associations/has_many_through_association.rb @@ -163,6 +163,36 @@ module ActiveRecord end end + def difference(a, b) + set_a = as_set(a) + set_b = as_set(b) + + from_set(set_a - set_b) + end + + def union(a, b) + set_a = as_set(a) + set_b = as_set(b) + + from_set(set_a & set_b) + end + + def as_set(records) + records.zip(occurences(records)) + end + + def from_set(record_set) + record_set.map(&:first) + end + + def occurences(array) + counts = Hash.new(0) + + array.map do |object| + counts[object] += 1 + end + end + def through_records_for(record) attributes = construct_join_attributes(record) candidates = Array.wrap(through_association.target) diff --git a/activerecord/test/cases/associations/has_many_through_associations_test.rb b/activerecord/test/cases/associations/has_many_through_associations_test.rb index 7b405c74c4..cf514957ca 100644 --- a/activerecord/test/cases/associations/has_many_through_associations_test.rb +++ b/activerecord/test/cases/associations/has_many_through_associations_test.rb @@ -586,6 +586,16 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase assert_not_includes posts(:welcome).reload.people.reload, people(:michael) end + def test_replace_association_with_duplicates + post = posts(:thinking) + person = people(:david) + + assert_difference "post.people.count", 2 do + post.people = [person] + post.people = [person, person] + end + end + def test_replace_order_is_preserved posts(:welcome).people.clear posts(:welcome).people = [people(:david), people(:michael)] |