Handle negated numeric in parser translation

Author: kddnewton

lib/prism/translation/parser/compiler.rb

@@ -247,6 +247,11 @@ def visit_call_node(node)
 
           if node.call_operator_loc.nil?
             case name
+            when :-@
+              case (receiver = node.receiver).type
+              when :integer_node, :float_node, :rational_node, :imaginary_node
+                return visit(numeric_negate(node.message_loc, receiver))
+              end
             when :!
               return visit_block(builder.not_op(token(node.message_loc), token(node.opening_loc), visit(node.receiver), token(node.closing_loc)), block)
             when :[]
@@ -792,7 +797,7 @@ def visit_if_node(node)
 
         # 1i
         def visit_imaginary_node(node)
-          visit_numeric(node, builder.complex([node.value, srange(node.location)]))
+          visit_numeric(node, builder.complex([imaginary_value(node), srange(node.location)]))
         end
 
         # { foo: }
@@ -1325,7 +1330,7 @@ def visit_range_node(node)
         # 1r
         # ^^
         def visit_rational_node(node)
-          visit_numeric(node, builder.rational([node.value, srange(node.location)]))
+          visit_numeric(node, builder.rational([rational_value(node), srange(node.location)]))
         end
 
         # redo
@@ -1690,6 +1695,26 @@ def find_forwarding(node)
           forwarding
         end
 
+        # Because we have mutated the AST to allow for newlines in the middle of
+        # a rational, we need to manually handle the value here.
+        def imaginary_value(node)
+          Complex(0, node.numeric.is_a?(RationalNode) ? rational_value(node.numeric) : node.numeric.value)
+        end
+
+        # Negate the value of a numeric node. This is a special case where you
+        # have a negative sign on one line and then a number on the next line.
+        # In normal Ruby, this will always be a method call. The parser gem,
+        # however, marks this as a numeric literal. We have to massage the tree
+        # here to get it into the correct form.
+        def numeric_negate(message_loc, receiver)
+          case receiver.type
+          when :integer_node, :float_node
+            receiver.copy(value: -receiver.value, location: message_loc.join(receiver.location))
+          when :rational_node, :imaginary_node
+            receiver.copy(numeric: numeric_negate(message_loc, receiver.numeric), location: message_loc.join(receiver.location))
+          end
+        end
+
         # Blocks can have a special set of parameters that automatically expand
         # when given arrays if they have a single required parameter and no
         # other parameters.
@@ -1704,6 +1729,16 @@ def procarg0?(parameters)
             parameters.block.nil?
         end
 
+        # Because we have mutated the AST to allow for newlines in the middle of
+        # a rational, we need to manually handle the value here.
+        def rational_value(node)
+          if node.numeric.is_a?(IntegerNode)
+            Rational(node.numeric.value)
+          else
+            Rational(node.slice.gsub(/\s/, "").chomp("r"))
+          end
+        end
+
         # Locations in the parser gem AST are generated using this class. We
         # store a reference to its constant to make it slightly faster to look
         # up.