FIX: Handle uncaught exception (#11263)

After the search term is parsed for advanced search filters, the term may
become empty. Later, the same term will be passed to Discourse.route_for
which will raise an ArgumentError.

> URI(nil)
ArgumentError: bad argument (expected URI object or URI string)

lib/discourse.rb

@@ -412,7 +412,7 @@ module Discourse
     unless uri.is_a?(URI)
       uri = begin
         URI(uri)
-      rescue URI::Error
+      rescue ArgumentError, URI::Error
       end
     end
 

lib/search.rb

@@ -266,15 +266,12 @@ class Search
       if @term =~ /^\d+$/
         single_topic(@term.to_i)
       else
-        begin
         if route = Discourse.route_for(@term)
           if route[:controller] == "topics" && route[:action] == "show"
             topic_id = (route[:id] || route[:topic_id]).to_i
             single_topic(topic_id) if topic_id > 0
           end
         end
-        rescue ActionController::RoutingError
-        end
       end
     end
 

spec/requests/search_controller_spec.rb

@@ -231,6 +231,11 @@ describe SearchController do
       expect(SearchLog.where(term: 'wookie')).to be_blank
     end
 
+    it "does not raise 500 with an empty term" do
+      get "/search/query.json", params: { term: "in:first", type_filter: "topic", search_for_id: true }
+      expect(response.status).to eq(200)
+    end
+
     context 'rate limited' do
       it 'rate limits anon searches per user' do
         SiteSetting.rate_limit_search_anon_user = 2