lib/lrama/counterexamples/example.rb in lrama-0.6.10 vs lib/lrama/counterexamples/example.rb in lrama-0.6.11

@@ -36,13 +36,14 @@
       end
 
       private
 
       def _derivations(paths)
-        derivation = nil
+        derivation = nil #: Derivation
         current = :production
-        lookahead_sym = paths.last.to.item.end_of_rule? ? @conflict_symbol : nil
+        last_path = paths.last #: Path
+        lookahead_sym = last_path.to.item.end_of_rule? ? @conflict_symbol : nil
 
         paths.reverse_each do |path|
           item = path.to.item
 
           case current
@@ -55,16 +56,18 @@
               derivation = Derivation.new(item, derivation)
               current = :transition
             when ProductionPath
               derivation = Derivation.new(item, derivation)
               current = :production
+            else
+              raise "Unexpected. #{path}"
             end
 
             if lookahead_sym && item.next_next_sym && item.next_next_sym.first_set.include?(lookahead_sym)
               state_item = @counterexamples.transitions[[path.to, item.next_sym]]
               derivation2 = find_derivation_for_symbol(state_item, lookahead_sym)
-              derivation.right = derivation2
+              derivation.right = derivation2 # steep:ignore
               lookahead_sym = nil
             end
 
           when :transition
             case path
@@ -87,10 +90,10 @@
 
         derivation
       end
 
       def find_derivation_for_symbol(state_item, sym)
-        queue = []
+        queue = [] #: Array[Array[StateItem]]
         queue << [state_item]
 
         while (sis = queue.shift)
           si = sis.last
           next_sym = si.item.next_sym