[Bug fix] Removing a tag from a record was affecting all records with…

… the same tag. Fixes mbleigh#538

lib/acts_as_taggable_on/acts_as_taggable_on/core.rb

@@ -382,7 +382,7 @@ def save_tags
 
         # Destroy old taggings:
         if old_tags.present?
-          ActsAsTaggableOn::Tagging.destroy_all(tagger_type: nil, tagger_id: nil, context: context.to_s, tag_id: old_tags)
+          self.taggings.owned_by.by_context(context).destroy_all(tag_id: old_tags)
         end
 
         # Create new taggings:

lib/acts_as_taggable_on/tagging.rb

@@ -15,6 +15,9 @@ class Tagging < ::ActiveRecord::Base #:nodoc:
     belongs_to :taggable, polymorphic: true
     belongs_to :tagger,   polymorphic: true
 
+    scope :owned_by, ->(owner = nil) { where(tagger: owner) }
+    scope :by_context, ->(context= :tags) { where(context: context) }
+
     validates_presence_of :context
     validates_presence_of :tag_id
 

spec/acts_as_taggable_on/tagging_spec.rb

@@ -23,5 +23,26 @@
       2.times { ActsAsTaggableOn::Tagging.create(taggable: @taggable, tag: @tag, context: 'tags') }
     }).to change(ActsAsTaggableOn::Tagging, :count).by(1)
   end
-
-end
+
+  it 'should not delete tags of other records' do
+    6.times { TaggableModel.create(name: 'Bob Jones', tag_list: 'very, serious, bug') }
+    expect(ActsAsTaggableOn::Tag.count).to eq(3)
+    taggable = TaggableModel.first
+    taggable.update(tag_list: 'bug')
+    expect(taggable.tag_list).to eq(['bug'])
+
+    another_taggable = TaggableModel.where('id != ?', taggable.id).first
+    expect(another_taggable.tag_list).to eq(%w(very serious bug))
+  end
+
+  context 'scopes' do
+    xdescribe '.by_context' do
+      # TODO
+    end
+
+    xdescribe '.owned_by' do
+      # TODO
+    end
+  end
+
+end