1 files changed, 43 insertions, 29 deletions

diff --git a/prism/templates/lib/prism/node.rb.erb b/prism/templates/lib/prism/node.rb.erb
index ddbe53e594..f0ce226def 100644
--- a/prism/templates/lib/prism/node.rb.erb
+++ b/prism/templates/lib/prism/node.rb.erb
@@ -28,17 +28,14 @@ module Prism
       location.is_a?(Location) ? location.end_offset : ((location >> 32) + (location & 0xFFFFFFFF))
     end
 
-    def newline? # :nodoc:
-      @newline ? true : false
+    # Returns all of the lines of the source code associated with this node.
+    def source_lines
+      location.source_lines
     end
 
-    def set_newline_flag(newline_marked) # :nodoc:
-      line = location.start_line
-      unless newline_marked[line]
-        newline_marked[line] = true
-        @newline = true
-      end
-    end
+    # An alias for source_lines, used to mimic the API from
+    # RubyVM::AbstractSyntaxTree to make it easier to migrate.
+    alias script_lines source_lines
 
     # Slice the location of the node from the source.
     def slice
@@ -67,6 +64,43 @@ module Prism
       DotVisitor.new.tap { |visitor| accept(visitor) }.to_dot
     end
 
+    # Returns a list of nodes that are descendants of this node that contain the
+    # given line and column. This is useful for locating a node that is selected
+    # based on the line and column of the source code.
+    #
+    # Important to note is that the column given to this method should be in
+    # bytes, as opposed to characters or code units.
+    def tunnel(line, column)
+      queue = [self] #: Array[Prism::node]
+      result = []
+
+      while (node = queue.shift)
+        result << node
+
+        node.compact_child_nodes.each do |child_node|
+          child_location = child_node.location
+
+          start_line = child_location.start_line
+          end_line = child_location.end_line
+
+          if start_line == end_line
+            if line == start_line && column >= child_location.start_column && column < child_location.end_column
+              queue << child_node
+              break
+            end
+          elsif (line == start_line && column >= child_location.start_column) || (line == end_line && column < child_location.end_column)
+            queue << child_node
+            break
+          elsif line > start_line && line < end_line
+            queue << child_node
+            break
+          end
+        end
+      end
+
+      result
+    end
+
     # Returns a list of the fields that exist for this node class. Fields
     # describe the structure of the node. This kind of reflection is useful for
     # things like recursively visiting each node _and_ field in the tree.
@@ -135,7 +169,6 @@ module Prism
     # def initialize: (<%= (node.fields.map { |field| "#{field.rbs_class} #{field.name}" } + ["Location location"]).join(", ") %>) -> void
     def initialize(source, <%= (node.fields.map(&:name) + ["location"]).join(", ") %>)
       @source = source
-      @newline = false
       @location = location
       <%- node.fields.each do |field| -%>
       <%- if Prism::Template::CHECK_FIELD_KIND && field.respond_to?(:check_field_kind) -%>
@@ -149,25 +182,6 @@ module Prism
     def accept(visitor)
       visitor.visit_<%= node.human %>(self)
     end
-    <%- if node.newline == false -%>
-
-    def set_newline_flag(newline_marked) # :nodoc:
-      # Never mark <%= node.name %> with a newline flag, mark children instead
-    end
-    <%- elsif node.newline.is_a?(String) -%>
-
-    def set_newline_flag(newline_marked) # :nodoc:
-      <%- field = node.fields.find { |f| f.name == node.newline } or raise node.newline -%>
-      <%- case field -%>
-      <%- when Prism::Template::NodeField -%>
-      <%= field.name %>.set_newline_flag(newline_marked)
-      <%- when Prism::Template::NodeListField -%>
-      first = <%= field.name %>.first
-      first.set_newline_flag(newline_marked) if first
-      <%- else raise field.class.name -%>
-      <%- end -%>
-    end
-    <%- end -%>
 
     # def child_nodes: () -> Array[nil | Node]
     def child_nodes