#308

backend/spec/requests/posts_spec.rb

@@ -927,16 +927,23 @@ RSpec.describe 'Posts API', type: :request do
       )
     end
 
-    it 'matches tag filter against current tags snapshot only' do
+    it 'filters versions by tag when the tag exists in either current or previous snapshot' do
       get '/posts/versions', params: { post: post_record.id, tag: tag.id }
 
       expect(response).to have_http_status(:ok)
-      expect(json.fetch('count')).to eq(1)
+      expect(json.fetch('count')).to eq(2)
 
       versions = json.fetch('versions')
-      expect(versions.size).to eq(1)
-      expect(versions[0]['version_no']).to eq(1)
-      expect(versions[0]['tags']).to include(
+      expect(versions.map { |v| v['post_id'] }).to all(eq(post_record.id))
+      expect(versions.map { |v| v['version_no'] }).to eq([2, 1])
+
+      latest = versions[0]
+      first = versions[1]
+
+      expect(latest['tags']).to include(
+        { 'name' => 'spec_tag', 'type' => 'removed' }
+      )
+      expect(first['tags']).to include(
         { 'name' => 'spec_tag', 'type' => 'added' }
       )
     end