Fixed the 500 and made bracketed literals parse as plain text #55 (#57)

Signed-off-by: Kai Wagner <kai.wagner@percona.com>

Author: ImTheKai

app/controllers/topics_controller.rb

@@ -194,6 +194,8 @@ def latest_patchset
 
   def search
     @search_query = params[:q].to_s.strip
+    @viewing_since = viewing_since_param
+    @new_topics_count = 0
 
     if @search_query.blank?
       respond_to do |format|

app/services/search/query_parser.rb

@@ -27,6 +27,11 @@ class Grammar < Parslet::Parser
         (word_char >> (word_char | str(':') >> word_char.present?).repeat).as(:word)
       end
 
+      # Bracketed text (treated as plain text, not dependent conditions)
+      rule(:bracketed_text) do
+        str('[') >> (str(']').absent? >> any).repeat.as(:bracketed_content) >> str(']')
+      end
+
       # Selector keywords - IMPORTANT: longer strings must come before shorter prefixes
       # e.g., "reading" before "read", "messages_after" before "messages"
       rule(:selector_key) do
@@ -99,6 +104,7 @@ class Grammar < Parslet::Parser
       rule(:atom) do
         selector.as(:selector) |
         grouped |
+        bracketed_text.as(:bracketed_text) |
         double_quoted.as(:quoted_text) |
         word.as(:plain_text)
       end
@@ -155,6 +161,14 @@ class Transform < Parslet::Transform
         { type: :text, value: c.to_s, negated: false, quoted: true }
       end
 
+      # Bracketed text node
+      rule(bracketed_text: { bracketed_content: simple(:c) }) do
+        { type: :text, value: "[#{c}]", negated: false, quoted: false }
+      end
+      rule(bracketed_text: { bracketed_content: sequence(:c) }) do
+        { type: :text, value: "[#{c.map(&:to_s).join}]", negated: false, quoted: false }
+      end
+
       # Selector with value and optional conditions
       rule(selector: { selector_key: simple(:k), selector_value: subtree(:v), conditions: subtree(:conds) }) do
         val = case v

spec/services/search/query_parser_spec.rb

@@ -14,6 +14,15 @@
         expect(result[:negated]).to be false
       end
 
+      it 'parses bracketed text as plain text' do
+        result = parser.parse('[proposal] plan')
+        expect(result[:type]).to eq(:and)
+        expect(result[:children].size).to eq(2)
+        expect(result[:children][0][:type]).to eq(:text)
+        expect(result[:children][0][:value]).to eq('[proposal]')
+        expect(result[:children][1][:value]).to eq('plan')
+      end
+
       it 'parses multiple words as implicit AND' do
         result = parser.parse('postgresql vacuum')
         expect(result[:type]).to eq(:and)