Merge pull request mbleigh#743 from emerson-h/master

Remove existing selects from relation

lib/acts_as_taggable_on/taggable/collection.rb

@@ -138,7 +138,7 @@ def generate_tagging_scope_in_clause(tagging_scope, table_name, primary_key)
           scoped_ids = pluck(table_name_pkey)
           tagging_scope = tagging_scope.where("#{ActsAsTaggableOn::Tagging.table_name}.taggable_id IN (?)", scoped_ids)
         else
-          tagging_scope = tagging_scope.where("#{ActsAsTaggableOn::Tagging.table_name}.taggable_id IN(#{safe_to_sql(select(table_name_pkey))})")
+          tagging_scope = tagging_scope.where("#{ActsAsTaggableOn::Tagging.table_name}.taggable_id IN(#{safe_to_sql(except(:select).select(table_name_pkey))})")
         end
 
         tagging_scope

spec/acts_as_taggable_on/taggable_spec.rb

@@ -119,6 +119,21 @@
     expect(@taggable.tag_counts_on(:tags).length).to eq(2)
   end
 
+  context 'tag_counts on a collection' do
+    context 'a select clause is specified on the collection' do
+      it 'should return tag counts without raising an error' do
+        expect(TaggableModel.tag_counts_on(:tags)).to be_empty
+
+        @taggable.tag_list = %w(awesome epic)
+        @taggable.save
+
+        expect {
+          expect(TaggableModel.select(:name).tag_counts_on(:tags).length).to eq(2)
+        }.not_to raise_error
+      end
+    end
+  end
+
   it 'should have tags_on' do
     expect(TaggableModel.tags_on(:tags)).to be_empty