Fix backend code for searching by a filetype as a combination of uploads and topic links. Add rspec test for extracting file extension in upload.

app/models/upload.rb

@@ -52,10 +52,6 @@ class Upload < ActiveRecord::Base
     end
   end
 
-  def extension
-    File.extname(original_filename)
-  end
-
   def self.generate_digest(path)
     Digest::SHA1.file(path).hexdigest
   end

lib/file_store/base_store.rb

@@ -95,7 +95,7 @@ module FileStore
     end
 
     def get_path_for_upload(upload)
-      get_path_for("original".freeze, upload.id, upload.sha1, upload.extension)
+      get_path_for("original".freeze, upload.id, upload.sha1, File.extname(upload.original_filename))
     end
 
     def get_path_for_optimized_image(optimized_image)

lib/search.rb

@@ -462,7 +462,11 @@ class Search
     posts.where("posts.id IN (
       SELECT post_id FROM topic_links
       WHERE extension IN (?)
-      )", file_extensions)
+      UNION
+      SELECT post_uploads.post_id FROM uploads
+      JOIN post_uploads ON post_uploads.upload_id = uploads.id
+      WHERE lower(uploads.extension) IN (?)
+      )", file_extensions, file_extensions)
   end
 
   private

spec/models/upload_spec.rb

@@ -46,6 +46,11 @@ describe Upload do
 
   end
 
+  it "extracts file extension" do
+    created_upload = UploadCreator.new(image, image_filename).create_for(user_id)
+    expect(created_upload.extension).to eq("png")
+  end
+
   context ".get_from_url" do
     let(:url) { "/uploads/default/original/3X/1/0/10f73034616a796dfd70177dc54b6def44c4ba6f.png" }
     let(:upload) { Fabricate(:upload, url: url) }