[ruby/prism] Include field comments in Java source

https://github.com/ruby/prism/commit/4a9389f304

prism/templates/include/prism/ast.h.erb

@@ -166,7 +166,13 @@ typedef struct pm_<%= node.human %> {
 <%- node.fields.grep_v(Prism::FlagsField).each do |field| -%>
 
     /**
-     * <%= node.name %>#<%= field.name %><%= "\n     *\n     * " + field.comment.split("\n").join("\n     * ") if field.comment %>
+     * <%= node.name %>#<%= field.name %>
+    <%- if field.comment -%>
+     *
+    <%- field.each_comment_line do |line| -%>
+     *<%= line %>
+    <%- end -%>
+    <%- end -%>
      */
     <%= case field
     when Prism::NodeField, Prism::OptionalNodeField then "struct #{field.c_type} *#{field.name}"

prism/templates/lib/prism/node.rb.erb

@@ -47,7 +47,9 @@ module Prism
     <%- if field.comment.nil? -%>
     # <%= "private " if field.is_a?(Prism::FlagsField) %>attr_reader <%= field.name %>: <%= field.rbs_class %>
     <%- else -%>
-    # <%= field.comment.split("\n").join("\n    # ") %>
+    <%- field.each_comment_line do |line| -%>
+    #<%= line %>
+    <%- end -%>
     <%- end -%>
     <%= "private " if field.is_a?(Prism::FlagsField) %>attr_reader :<%= field.name %>
 

prism/templates/template.rb

@@ -21,6 +21,10 @@ module Prism
       @options = options
     end
 
+    def each_comment_line
+      comment.each_line { |line| yield line.prepend(" ").rstrip } if comment
+    end
+
     def semantic_field?
       true
     end