[ruby/prism] Speed up creating Ruby AST

When creating the Ruby AST, we were previously allocating Location
objects for every node and every inner location. Instead, this
commit changes it to pack both the start offset and length into a
single u64 and pass that into the nodes. Then, when the locations
are requested via a reader method, we lazily allocate the Location
objects.

https://github.com/ruby/prism/commit/de203dca83

Co-Authored-By: Aaron Patterson <tenderlove@ruby-lang.org>

8 files changed, 311 insertions, 120 deletions

diff --git a/lib/prism/desugar_compiler.rb b/lib/prism/desugar_compiler.rb
index daca02f35e..00b3097f9f 100644
--- a/lib/prism/desugar_compiler.rb
+++ b/lib/prism/desugar_compiler.rb
@@ -1,6 +1,216 @@
 # frozen_string_literal: true
 
 module Prism
+  class DesugarAndWriteNode # :nodoc:
+    attr_reader :node, :source, :read_class, :write_class, :arguments
+
+    def initialize(node, source, read_class, write_class, *arguments)
+      @node = node
+      @source = source
+      @read_class = read_class
+      @write_class = write_class
+      @arguments = arguments
+    end
+
+    # Desugar `x &&= y` to `x && x = y`
+    def compile
+      AndNode.new(
+        source,
+        read_class.new(source, *arguments, node.name_loc),
+        write_class.new(source, *arguments, node.name_loc, node.value, node.operator_loc, node.location),
+        node.operator_loc,
+        node.location
+      )
+    end
+  end
+
+  class DesugarOrWriteDefinedNode # :nodoc:
+    attr_reader :node, :source, :read_class, :write_class, :arguments
+
+    def initialize(node, source, read_class, write_class, *arguments)
+      @node = node
+      @source = source
+      @read_class = read_class
+      @write_class = write_class
+      @arguments = arguments
+    end
+
+    # Desugar `x ||= y` to `defined?(x) ? x : x = y`
+    def compile
+      IfNode.new(
+        source,
+        node.operator_loc,
+        DefinedNode.new(source, nil, read_class.new(source, *arguments, node.name_loc), nil, node.operator_loc, node.name_loc),
+        node.operator_loc,
+        StatementsNode.new(source, [read_class.new(source, *arguments, node.name_loc)], node.location),
+        ElseNode.new(
+          source,
+          node.operator_loc,
+          StatementsNode.new(
+            source,
+            [write_class.new(source, *arguments, node.name_loc, node.value, node.operator_loc, node.location)],
+            node.location
+          ),
+          node.operator_loc,
+          node.location
+        ),
+        node.operator_loc,
+        node.location
+      )
+    end
+  end
+
+  class DesugarOperatorWriteNode # :nodoc:
+    attr_reader :node, :source, :read_class, :write_class, :arguments
+
+    def initialize(node, source, read_class, write_class, *arguments)
+      @node = node
+      @source = source
+      @read_class = read_class
+      @write_class = write_class
+      @arguments = arguments
+    end
+
+    # Desugar `x += y` to `x = x + y`
+    def compile
+      write_class.new(
+        source,
+        *arguments,
+        node.name_loc,
+        CallNode.new(
+          source,
+          0,
+          read_class.new(source, *arguments, node.name_loc),
+          nil,
+          node.operator_loc.slice.chomp("="),
+          node.operator_loc.copy(length: node.operator_loc.length - 1),
+          nil,
+          ArgumentsNode.new(source, 0, [node.value], node.value.location),
+          nil,
+          nil,
+          node.location
+        ),
+        node.operator_loc.copy(start_offset: node.operator_loc.end_offset - 1, length: 1),
+        node.location
+      )
+    end
+  end
+
+  class DesugarOrWriteNode # :nodoc:
+    attr_reader :node, :source, :read_class, :write_class, :arguments
+
+    def initialize(node, source, read_class, write_class, *arguments)
+      @node = node
+      @source = source
+      @read_class = read_class
+      @write_class = write_class
+      @arguments = arguments
+    end
+
+    # Desugar `x ||= y` to `x || x = y`
+    def compile
+      OrNode.new(
+        source,
+        read_class.new(source, *arguments, node.name_loc),
+        write_class.new(source, *arguments, node.name_loc, node.value, node.operator_loc, node.location),
+        node.operator_loc,
+        node.location
+      )
+    end
+  end
+
+  private_constant :DesugarAndWriteNode, :DesugarOrWriteNode, :DesugarOrWriteDefinedNode, :DesugarOperatorWriteNode
+
+  class ClassVariableAndWriteNode
+    def desugar # :nodoc:
+      DesugarAndWriteNode.new(self, source, ClassVariableReadNode, ClassVariableWriteNode, name).compile
+    end
+  end
+
+  class ClassVariableOrWriteNode
+    def desugar # :nodoc:
+      DesugarOrWriteDefinedNode.new(self, source, ClassVariableReadNode, ClassVariableWriteNode, name).compile
+    end
+  end
+
+  class ClassVariableOperatorWriteNode
+    def desugar # :nodoc:
+      DesugarOperatorWriteNode.new(self, source, ClassVariableReadNode, ClassVariableWriteNode, name).compile
+    end
+  end
+
+  class ConstantAndWriteNode
+    def desugar # :nodoc:
+      DesugarAndWriteNode.new(self, source, ConstantReadNode, ConstantWriteNode, name).compile
+    end
+  end
+
+  class ConstantOrWriteNode
+    def desugar # :nodoc:
+      DesugarOrWriteDefinedNode.new(self, source, ConstantReadNode, ConstantWriteNode, name).compile
+    end
+  end
+
+  class ConstantOperatorWriteNode
+    def desugar # :nodoc:
+      DesugarOperatorWriteNode.new(self, source, ConstantReadNode, ConstantWriteNode, name).compile
+    end
+  end
+
+  class GlobalVariableAndWriteNode
+    def desugar # :nodoc:
+      DesugarAndWriteNode.new(self, source, GlobalVariableReadNode, GlobalVariableWriteNode, name).compile
+    end
+  end
+
+  class GlobalVariableOrWriteNode
+    def desugar # :nodoc:
+      DesugarOrWriteDefinedNode.new(self, source, GlobalVariableReadNode, GlobalVariableWriteNode, name).compile
+    end
+  end
+
+  class GlobalVariableOperatorWriteNode
+    def desugar # :nodoc:
+      DesugarOperatorWriteNode.new(self, source, GlobalVariableReadNode, GlobalVariableWriteNode, name).compile
+    end
+  end
+
+  class InstanceVariableAndWriteNode
+    def desugar # :nodoc:
+      DesugarAndWriteNode.new(self, source, InstanceVariableReadNode, InstanceVariableWriteNode, name).compile
+    end
+  end
+
+  class InstanceVariableOrWriteNode
+    def desugar # :nodoc:
+      DesugarOrWriteNode.new(self, source, InstanceVariableReadNode, InstanceVariableWriteNode, name).compile
+    end
+  end
+
+  class InstanceVariableOperatorWriteNode
+    def desugar # :nodoc:
+      DesugarOperatorWriteNode.new(self, source, InstanceVariableReadNode, InstanceVariableWriteNode, name).compile
+    end
+  end
+
+  class LocalVariableAndWriteNode
+    def desugar # :nodoc:
+      DesugarAndWriteNode.new(self, source, LocalVariableReadNode, LocalVariableWriteNode, name, depth).compile
+    end
+  end
+
+  class LocalVariableOrWriteNode
+    def desugar # :nodoc:
+      DesugarOrWriteNode.new(self, source, LocalVariableReadNode, LocalVariableWriteNode, name, depth).compile
+    end
+  end
+
+  class LocalVariableOperatorWriteNode
+    def desugar # :nodoc:
+      DesugarOperatorWriteNode.new(self, source, LocalVariableReadNode, LocalVariableWriteNode, name, depth).compile
+    end
+  end
+
   # DesugarCompiler is a compiler that desugars Ruby code into a more primitive
   # form. This is useful for consumers that want to deal with fewer node types.
   class DesugarCompiler < MutationCompiler
@@ -10,7 +220,7 @@ module Prism
     #
     # @@foo && @@foo = bar
     def visit_class_variable_and_write_node(node)
-      desugar_and_write_node(node, ClassVariableReadNode, ClassVariableWriteNode, node.name)
+      node.desugar
     end
 
     # @@foo ||= bar
@@ -19,7 +229,7 @@ module Prism
     #
     # defined?(@@foo) ? @@foo : @@foo = bar
     def visit_class_variable_or_write_node(node)
-      desugar_or_write_defined_node(node, ClassVariableReadNode, ClassVariableWriteNode, node.name)
+      node.desugar
     end
 
     # @@foo += bar
@@ -28,7 +238,7 @@ module Prism
     #
     # @@foo = @@foo + bar
     def visit_class_variable_operator_write_node(node)
-      desugar_operator_write_node(node, ClassVariableReadNode, ClassVariableWriteNode, node.name)
+      node.desugar
     end
 
     # Foo &&= bar
@@ -37,7 +247,7 @@ module Prism
     #
     # Foo && Foo = bar
     def visit_constant_and_write_node(node)
-      desugar_and_write_node(node, ConstantReadNode, ConstantWriteNode, node.name)
+      node.desugar
     end
 
     # Foo ||= bar
@@ -46,7 +256,7 @@ module Prism
     #
     # defined?(Foo) ? Foo : Foo = bar
     def visit_constant_or_write_node(node)
-      desugar_or_write_defined_node(node, ConstantReadNode, ConstantWriteNode, node.name)
+      node.desugar
     end
 
     # Foo += bar
@@ -55,7 +265,7 @@ module Prism
     #
     # Foo = Foo + bar
     def visit_constant_operator_write_node(node)
-      desugar_operator_write_node(node, ConstantReadNode, ConstantWriteNode, node.name)
+      node.desugar
     end
 
     # $foo &&= bar
@@ -64,7 +274,7 @@ module Prism
     #
     # $foo && $foo = bar
     def visit_global_variable_and_write_node(node)
-      desugar_and_write_node(node, GlobalVariableReadNode, GlobalVariableWriteNode, node.name)
+      node.desugar
     end
 
     # $foo ||= bar
@@ -73,7 +283,7 @@ module Prism
     #
     # defined?($foo) ? $foo : $foo = bar
     def visit_global_variable_or_write_node(node)
-      desugar_or_write_defined_node(node, GlobalVariableReadNode, GlobalVariableWriteNode, node.name)
+      node.desugar
     end
 
     # $foo += bar
@@ -82,7 +292,7 @@ module Prism
     #
     # $foo = $foo + bar
     def visit_global_variable_operator_write_node(node)
-      desugar_operator_write_node(node, GlobalVariableReadNode, GlobalVariableWriteNode, node.name)
+      node.desugar
     end
 
     # @foo &&= bar
@@ -91,7 +301,7 @@ module Prism
     #
     # @foo && @foo = bar
     def visit_instance_variable_and_write_node(node)
-      desugar_and_write_node(node, InstanceVariableReadNode, InstanceVariableWriteNode, node.name)
+      node.desugar
     end
 
     # @foo ||= bar
@@ -100,7 +310,7 @@ module Prism
     #
     # @foo || @foo = bar
     def visit_instance_variable_or_write_node(node)
-      desugar_or_write_node(node, InstanceVariableReadNode, InstanceVariableWriteNode, node.name)
+      node.desugar
     end
 
     # @foo += bar
@@ -109,7 +319,7 @@ module Prism
     #
     # @foo = @foo + bar
     def visit_instance_variable_operator_write_node(node)
-      desugar_operator_write_node(node, InstanceVariableReadNode, InstanceVariableWriteNode, node.name)
+      node.desugar
     end
 
     # foo &&= bar
@@ -118,7 +328,7 @@ module Prism
     #
     # foo && foo = bar
     def visit_local_variable_and_write_node(node)
-      desugar_and_write_node(node, LocalVariableReadNode, LocalVariableWriteNode, node.name, node.depth)
+      node.desugar
     end
 
     # foo ||= bar
@@ -127,7 +337,7 @@ module Prism
     #
     # foo || foo = bar
     def visit_local_variable_or_write_node(node)
-      desugar_or_write_node(node, LocalVariableReadNode, LocalVariableWriteNode, node.name, node.depth)
+      node.desugar
     end
 
     # foo += bar
@@ -136,72 +346,7 @@ module Prism
     #
     # foo = foo + bar
     def visit_local_variable_operator_write_node(node)
-      desugar_operator_write_node(node, LocalVariableReadNode, LocalVariableWriteNode, node.name, node.depth)
-    end
-
-    private
-
-    # Desugar `x &&= y` to `x && x = y`
-    def desugar_and_write_node(node, read_class, write_class, *arguments)
-      AndNode.new(
-        read_class.new(*arguments, node.name_loc),
-        write_class.new(*arguments, node.name_loc, node.value, node.operator_loc, node.location),
-        node.operator_loc,
-        node.location
-      )
-    end
-
-    # Desugar `x += y` to `x = x + y`
-    def desugar_operator_write_node(node, read_class, write_class, *arguments)
-      write_class.new(
-        *arguments,
-        node.name_loc,
-        CallNode.new(
-          0,
-          read_class.new(*arguments, node.name_loc),
-          nil,
-          node.operator_loc.slice.chomp("="),
-          node.operator_loc.copy(length: node.operator_loc.length - 1),
-          nil,
-          ArgumentsNode.new(0, [node.value], node.value.location),
-          nil,
-          nil,
-          node.location
-        ),
-        node.operator_loc.copy(start_offset: node.operator_loc.end_offset - 1, length: 1),
-        node.location
-      )
-    end
-
-    # Desugar `x ||= y` to `x || x = y`
-    def desugar_or_write_node(node, read_class, write_class, *arguments)
-      OrNode.new(
-        read_class.new(*arguments, node.name_loc),
-        write_class.new(*arguments, node.name_loc, node.value, node.operator_loc, node.location),
-        node.operator_loc,
-        node.location
-      )
-    end
-
-    # Desugar `x ||= y` to `defined?(x) ? x : x = y`
-    def desugar_or_write_defined_node(node, read_class, write_class, *arguments)
-      IfNode.new(
-        node.operator_loc,
-        DefinedNode.new(nil, read_class.new(*arguments, node.name_loc), nil, node.operator_loc, node.name_loc),
-        node.operator_loc,
-        StatementsNode.new([read_class.new(*arguments, node.name_loc)], node.location),
-        ElseNode.new(
-          node.operator_loc,
-          StatementsNode.new(
-            [write_class.new(*arguments, node.name_loc, node.value, node.operator_loc, node.location)],
-            node.location
-          ),
-          node.operator_loc,
-          node.location
-        ),
-        node.operator_loc,
-        node.location
-      )
+      node.desugar
     end
   end
 end
diff --git a/lib/prism/parse_result.rb b/lib/prism/parse_result.rb
index bcebc1a437..5b22184ef1 100644
--- a/lib/prism/parse_result.rb
+++ b/lib/prism/parse_result.rb
@@ -452,17 +452,19 @@ module Prism
 
   # This represents a token from the Ruby source.
   class Token
+    # The Source object that represents the source this token came from.
+    attr_reader :source
+    private :source
+
     # The type of token that this token is.
     attr_reader :type
 
     # A byteslice of the source that this token represents.
     attr_reader :value
 
-    # A Location object representing the location of this token in the source.
-    attr_reader :location
-
     # Create a new token object with the given type, value, and location.
-    def initialize(type, value, location)
+    def initialize(source, type, value, location)
+      @source = source
       @type = type
       @value = value
       @location = location
@@ -473,6 +475,12 @@ module Prism
       { type: type, value: value, location: location }
     end
 
+    # A Location object representing the location of this token in the source.
+    def location
+      return @location if @location.is_a?(Location)
+      @location = Location.new(source, @location >> 32, @location & 0xFFFFFFFF)
+    end
+
     # Implement the pretty print interface for Token.
     def pretty_print(q)
       q.group do
diff --git a/lib/prism/translation/parser/compiler.rb b/lib/prism/translation/parser/compiler.rb
index 264d85c261..81156a64c7 100644
--- a/lib/prism/translation/parser/compiler.rb
+++ b/lib/prism/translation/parser/compiler.rb
@@ -1477,7 +1477,7 @@ module Prism
         # ^^^^^
         def visit_string_node(node)
           if node.opening&.start_with?("<<")
-            children, closing = visit_heredoc(InterpolatedStringNode.new(node.opening_loc, [node.copy(opening_loc: nil, closing_loc: nil, location: node.content_loc)], node.closing_loc, node.location))
+            children, closing = visit_heredoc(InterpolatedStringNode.new(node.send(:source), node.opening_loc, [node.copy(opening_loc: nil, closing_loc: nil, location: node.content_loc)], node.closing_loc, node.location))
             builder.string_compose(token(node.opening_loc), children, closing)
           elsif node.opening == "?"
             builder.character([node.unescaped, srange(node.location)])
diff --git a/prism/templates/ext/prism/api_node.c.erb b/prism/templates/ext/prism/api_node.c.erb
index f52d537dbc..55867f078c 100644
--- a/prism/templates/ext/prism/api_node.c.erb
+++ b/prism/templates/ext/prism/api_node.c.erb
@@ -12,23 +12,24 @@ static VALUE rb_cPrism<%= node.name %>;
 <%- end -%>
 
 static VALUE
-pm_location_new(pm_parser_t *parser, const uint8_t *start, const uint8_t *end, VALUE source) {
-    VALUE argv[] = { source, LONG2FIX(start - parser->start), LONG2FIX(end - start) };
-    return rb_class_new_instance(3, argv, rb_cPrismLocation);
+pm_location_new(pm_parser_t *parser, const uint8_t *start, const uint8_t *end) {
+    uint64_t value = ((((uint64_t) (start - parser->start)) << 32) | ((uint32_t) (end - start)));
+    return ULL2NUM(value);
 }
 
 VALUE
 pm_token_new(pm_parser_t *parser, pm_token_t *token, rb_encoding *encoding, VALUE source) {
     ID type = rb_intern(pm_token_type_name(token->type));
-    VALUE location = pm_location_new(parser, token->start, token->end, source);
+    VALUE location = pm_location_new(parser, token->start, token->end);
 
     VALUE argv[] = {
+        source,
         ID2SYM(type),
         rb_enc_str_new((const char *) token->start, token->end - token->start, encoding),
         location
     };
 
-    return rb_class_new_instance(3, argv, rb_cPrismToken);
+    return rb_class_new_instance(4, argv, rb_cPrismToken);
 }
 
 static VALUE
@@ -144,8 +145,11 @@ pm_ast_new(pm_parser_t *parser, pm_node_t *node, rb_encoding *encoding, VALUE so
                     <%- if node.fields.any? { |field| ![Prism::NodeField, Prism::OptionalNodeField, Prism::FlagsField].include?(field.class) } -%>
                     pm_<%= node.human %>_t *cast = (pm_<%= node.human %>_t *) node;
                     <%- end -%>
-                    VALUE argv[<%= node.fields.length + 1 %>];
-                    <%- node.fields.each_with_index do |field, index| -%>
+                    VALUE argv[<%= node.fields.length + 2 %>];
+
+                    // source
+                    argv[0] = source;
+                    <%- node.fields.each.with_index(1) do |field, index| -%>
 
                     // <%= field.name %>
                     <%- case field -%>
@@ -176,10 +180,10 @@ pm_ast_new(pm_parser_t *parser, pm_node_t *node, rb_encoding *encoding, VALUE so
                     }
                     <%- when Prism::LocationField -%>
 #line <%= __LINE__ + 1 %> "<%= File.basename(__FILE__) %>"
-                    argv[<%= index %>] = pm_location_new(parser, cast-><%= field.name %>.start, cast-><%= field.name %>.end, source);
+                    argv[<%= index %>] = pm_location_new(parser, cast-><%= field.name %>.start, cast-><%= field.name %>.end);
                     <%- when Prism::OptionalLocationField -%>
 #line <%= __LINE__ + 1 %> "<%= File.basename(__FILE__) %>"
-                    argv[<%= index %>] = cast-><%= field.name %>.start == NULL ? Qnil : pm_location_new(parser, cast-><%= field.name %>.start, cast-><%= field.name %>.end, source);
+                    argv[<%= index %>] = cast-><%= field.name %>.start == NULL ? Qnil : pm_location_new(parser, cast-><%= field.name %>.start, cast-><%= field.name %>.end);
                     <%- when Prism::UInt8Field -%>
 #line <%= __LINE__ + 1 %> "<%= File.basename(__FILE__) %>"
                     argv[<%= index %>] = UINT2NUM(cast-><%= field.name %>);
@@ -195,9 +199,9 @@ pm_ast_new(pm_parser_t *parser, pm_node_t *node, rb_encoding *encoding, VALUE so
                     <%- end -%>
 
                     // location
-                    argv[<%= node.fields.length %>] = pm_location_new(parser, node->location.start, node->location.end, source);
+                    argv[<%= node.fields.length + 1 %>] = pm_location_new(parser, node->location.start, node->location.end);
 
-                    rb_ary_push(value_stack, rb_class_new_instance(<%= node.fields.length + 1 %>, argv, rb_cPrism<%= node.name %>));
+                    rb_ary_push(value_stack, rb_class_new_instance(<%= node.fields.length + 2 %>, argv, rb_cPrism<%= node.name %>));
                     break;
                 }
                 <%- end -%>
diff --git a/prism/templates/lib/prism/dsl.rb.erb b/prism/templates/lib/prism/dsl.rb.erb
index be18ad45ba..d21cf53022 100644
--- a/prism/templates/lib/prism/dsl.rb.erb
+++ b/prism/templates/lib/prism/dsl.rb.erb
@@ -9,10 +9,12 @@ module Prism
   #         Prism::IntegerNode.new(
   #           Prism::IntegerBaseFlags::DECIMAL,
   #           Prism::Location.new(source, 1, 1),
+  #           source
   #         )
   #       ],
   #       Prism::Location.new(source, 0, 1),
-  #       Prism::Location.new(source, 2, 1)
+  #       Prism::Location.new(source, 2, 1),
+  #       source
   #     )
   #
   # you could instead write:
@@ -20,9 +22,10 @@ module Prism
   #     source = Prism::Source.new("[1]")
   #
   #     ArrayNode(
-  #       IntegerNode(Prism::IntegerBaseFlags::DECIMAL, Location(source, 1, 1))),
+  #       IntegerNode(Prism::IntegerBaseFlags::DECIMAL, Location(source, 1, 1)), source),
   #       Location(source, 0, 1),
-  #       Location(source, 2, 1)
+  #       Location(source, 2, 1),
+  #       source
   #     )
   #
   # This is mostly helpful in the context of writing tests, but can also be used
@@ -37,8 +40,8 @@ module Prism
     <%- nodes.each do |node| -%>
 
     # Create a new <%= node.name %> node
-    def <%= node.name %>(<%= (node.fields.map(&:name) + ["location = Location()"]).join(", ") %>)
-      <%= node.name %>.new(<%= (node.fields.map(&:name) + ["location"]).join(", ") %>)
+    def <%= node.name %>(<%= (node.fields.map(&:name) + ["source = nil, location = Location()"]).join(", ") %>)
+      <%= node.name %>.new(<%= ["source", *node.fields.map(&:name), "location"].join(", ") %>)
     end
     <%- end -%>
   end
diff --git a/prism/templates/lib/prism/node.rb.erb b/prism/templates/lib/prism/node.rb.erb
index b74d39c0e3..81a007fcd3 100644
--- a/prism/templates/lib/prism/node.rb.erb
+++ b/prism/templates/lib/prism/node.rb.erb
@@ -2,9 +2,16 @@ module Prism
   # This represents a node in the tree. It is the parent class of all of the
   # various node types.
   class Node
+    # A pointer to the source that this node was created from.
+    attr_reader :source
+    private :source
+
     # A Location instance that represents the location of this node in the
     # source.
-    attr_reader :location
+    def location
+      return @location if @location.is_a?(Location)
+      @location = Location.new(source, @location >> 32, @location & 0xFFFFFFFF)
+    end
 
     def newline? # :nodoc:
       @newline ? true : false
@@ -52,7 +59,7 @@ module Prism
     # Returns an array of child nodes, including `nil`s in the place of optional
     # nodes that were not present.
     def child_nodes
-      raise NoMethodError, "undefined method `#{__method__}' for #{inspect}"
+      raise NoMethodError, "undefined method `child_nodes' for #{inspect}"
     end
 
     alias deconstruct child_nodes
@@ -81,24 +88,14 @@ module Prism
   #<%= line %>
   <%- end -%>
   class <%= node.name -%> < Node
-    <%- node.fields.each do |field| -%>
-    <%- if field.comment.nil? -%>
-    # <%= "private " if field.is_a?(Prism::FlagsField) %>attr_reader <%= field.name %>: <%= field.rbs_class %>
-    <%- else -%>
-    <%- field.each_comment_line do |line| -%>
-    #<%= line %>
-    <%- end -%>
-    <%- end -%>
-    attr_reader :<%= field.name -%><%= "\n    private :#{field.name}" if field.is_a?(Prism::FlagsField) %>
-
-    <%- end -%>
     # def initialize: (<%= (node.fields.map { |field| "#{field.rbs_class} #{field.name}" } + ["Location location"]).join(", ") %>) -> void
-    def initialize(<%= (node.fields.map(&:name) + ["location"]).join(", ") %>)
+    def initialize(source, <%= (node.fields.map(&:name) + ["location"]).join(", ") %>)
+      @source = source
       @newline = false
+      @location = location
       <%- node.fields.each do |field| -%>
       @<%= field.name %> = <%= field.name %>
       <%- end -%>
-      @location = location
     end
 
     # def accept: (Visitor visitor) -> void
@@ -173,6 +170,7 @@ module Prism
     # def copy: (**params) -> <%= node.name %>
     def copy(**params)
       <%= node.name %>.new(
+        source,
         <%- (node.fields.map(&:name) + ["location"]).map do |name| -%>
         params.fetch(:<%= name %>) { <%= name %> },
         <%- end -%>
@@ -186,6 +184,37 @@ module Prism
     def deconstruct_keys(keys)
       { <%= (node.fields.map { |field| "#{field.name}: #{field.name}" } + ["location: location"]).join(", ") %> }
     end
+
+    <%- node.fields.each do |field| -%>
+    <%- if field.comment.nil? -%>
+    # <%= "private " if field.is_a?(Prism::FlagsField) %>attr_reader <%= field.name %>: <%= field.rbs_class %>
+    <%- else -%>
+    <%- field.each_comment_line do |line| -%>
+    #<%= line %>
+    <%- end -%>
+    <%- end -%>
+    <%- case field -%>
+    <%- when Prism::LocationField -%>
+    def <%= field.name %>
+      return @<%= field.name %> if @<%= field.name %>.is_a?(Location)
+      @<%= field.name %> = Location.new(source, @<%= field.name %> >> 32, @<%= field.name %> & 0xFFFFFFFF)
+    end
+    <%- when Prism::OptionalLocationField -%>
+    def <%= field.name %>
+      case @<%= field.name %>
+      when nil
+        nil
+      when Location
+        @<%= field.name %>
+      else
+        @<%= field.name %> = Location.new(source, @<%= field.name %> >> 32, @<%= field.name %> & 0xFFFFFFFF)
+      end
+    end
+    <%- else -%>
+    attr_reader :<%= field.name -%><%= "\n    private :#{field.name}" if field.is_a?(Prism::FlagsField) %>
+    <%- end -%>
+
+    <%- end -%>
     <%- node.fields.each do |field| -%>
     <%- case field -%>
     <%- when Prism::LocationField -%>
diff --git a/prism/templates/lib/prism/serialize.rb.erb b/prism/templates/lib/prism/serialize.rb.erb
index 751341ce2f..af03a54b48 100644
--- a/prism/templates/lib/prism/serialize.rb.erb
+++ b/prism/templates/lib/prism/serialize.rb.erb
@@ -112,7 +112,7 @@ module Prism
           length = load_varuint
           lex_state = load_varuint
           location = Location.new(@source, start, length)
-          tokens << [Prism::Token.new(type, location.slice, location), lex_state]
+          tokens << [Prism::Token.new(source, type, location.slice, location), lex_state]
         end
 
         tokens
@@ -274,7 +274,8 @@ module Prism
             <%- if node.needs_serialized_length? -%>
             load_serialized_length
             <%- end -%>
-            <%= node.name %>.new(<%= (node.fields.map { |field|
+            <%= node.name %>.new(
+              source, <%= (node.fields.map { |field|
               case field
               when Prism::NodeField then "load_node"
               when Prism::OptionalNodeField then "load_optional_node"
@@ -308,7 +309,8 @@ module Prism
               <%- if node.needs_serialized_length? -%>
               load_serialized_length
               <%- end -%>
-              <%= node.name %>.new(<%= (node.fields.map { |field|
+              <%= node.name %>.new(
+                source, <%= (node.fields.map { |field|
                 case field
                 when Prism::NodeField then "load_node"
                 when Prism::OptionalNodeField then "load_optional_node"
diff --git a/test/prism/newline_test.rb b/test/prism/newline_test.rb
index 3d42ca99cd..eea69ec5e1 100644
--- a/test/prism/newline_test.rb
+++ b/test/prism/newline_test.rb
@@ -7,7 +7,7 @@ return unless defined?(RubyVM::InstructionSequence)
 module Prism
   class NewlineTest < TestCase
     base = File.expand_path("../", __FILE__)
-    filepaths = Dir["*.rb", base: base] - %w[encoding_test.rb parser_test.rb unescape_test.rb]
+    filepaths = Dir["*.rb", base: base] - %w[encoding_test.rb errors_test.rb parser_test.rb unescape_test.rb]
 
     filepaths.each do |relative|
       define_method("test_newline_flags_#{relative}") do