Get rid of use of special variables

Use `"\n"` and `IO#fileno` instead of `$/` and `$.` respectively.
[Feature #14240]

ext/ripper/tools/preproc.rb

@@ -45,7 +45,7 @@ def prelude(f, out)
   while line = f.gets
     case line
     when /\A%%/
-      out << '%%' << $/
+      out << "%%\n"
       return
     when /\A%token/
       out << line.sub(/<\w+>/, '<val>')
@@ -79,15 +79,15 @@ def grammar(f, out)
   while line = f.gets
     case line
     when %r</\*% *ripper(?:\[(.*?)\])?: *(.*?) *%\*/>
-      out << DSL.new($2, ($1 || "").split(",")).generate << $/
+      out << DSL.new($2, ($1 || "").split(",")).generate << "\n"
     when %r</\*%%%\*/>
-      out << '#if 0' << $/
+      out << "#if 0\n"
     when %r</\*%>
-      out << '#endif' << $/
+      out << "#endif\n"
     when %r<%\*/>
-      out << $/
+      out << "\n"
     when /\A%%/
-      out << '%%' << $/
+      out << "%%\n"
       return
     else
       out << line

template/encdb.h.tmpl

@@ -58,7 +58,7 @@ encdirs.each do |encdir|
           else
             name = $1
           end
-          check_duplication(defs, $1, fn, $.)
+          check_duplication(defs, $1, fn, f.lineno)
           next if BUILTIN_ENCODINGS[name]
           encodings << $1
           count += 1
@@ -71,18 +71,18 @@ encdirs.each do |encdir|
           when /^ENC_REPLICATE\(\s*"([^"]+)"\s*,\s*"([^"]+)"/
             raise ArgumentError,
             '%s:%d: ENC_REPLICATE: %s is not defined yet. (replica %s)' %
-              [fn, $., $2, $1] unless defs[$2.upcase]
+              [fn, f.lineno, $2, $1] unless defs[$2.upcase]
             count += 1
           when /^ENC_ALIAS\(\s*"([^"]+)"\s*,\s*"([^"]+)"/
             raise ArgumentError,
             '%s:%d: ENC_ALIAS: %s is not defined yet. (alias %s)' %
-              [fn, $., $2, $1] unless defs[$2.upcase]
+              [fn, f.lineno, $2, $1] unless defs[$2.upcase]
           when /^ENC_DUMMY\w*\(\s*"([^"]+)"/
             count += 1
           else
             next
           end
-          check_duplication(defs, $1, fn, $.)
+          check_duplication(defs, $1, fn, f.lineno)
           lines << line.sub(/;.*/m, "").chomp + ";" if line
         end
       end

template/transdb.h.tmpl

@@ -44,9 +44,9 @@ transdirs.each do |transdir|
           from_to = "%s to %s" % [$1, $2]
           if converters[from_to]
             raise ArgumentError, '%s:%d: transcode "%s" is already registered at %s:%d' %
-            [path, $., from_to, *converters[from_to].values_at(3, 4)]
+            [path, f.lineno, from_to, *converters[from_to].values_at(3, 4)]
           else
-            converters[from_to] = [$1, $2, fn[0..-3], path, $.]
+            converters[from_to] = [$1, $2, fn[0..-3], path, f.lineno]
             converter_list << from_to
           end
         end