generic_erb.rb: --vpath option

* tool/generic_erb.rb (vpath.open): move --vpath option from
  template/id.h.tmpl.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@36822 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 15 insertions, 1 deletions

diff --git a/tool/generic_erb.rb b/tool/generic_erb.rb
index 8e84a46bfd..b2b988fb3a 100755
--- a/tool/generic_erb.rb
+++ b/tool/generic_erb.rb
@@ -2,13 +2,27 @@ require 'erb'
 require 'optparse'
 require 'fileutils'
 
+vpath = ["."]
+def vpath.open(file, *rest)
+  find do |dir|
+    begin
+      path = File.join(dir, file)
+      return File.open(path, *rest) {|f| yield(f)}
+    rescue Errno::ENOENT
+      nil
+    end
+  end or raise(Errno::ENOENT, file)
+end
+
 timestamp = nil
 output = nil
 ifchange = nil
+
 opt = OptionParser.new do |o|
   o.on('-t', '--timestamp[=PATH]') {|v| timestamp = v || true}
   o.on('-o', '--output=PATH') {|v| output = v}
   o.on('-c', '--[no-]if-change') {|v| ifchange = v}
+  o.on('-v', '--vpath=DIR') {|dirs| vpath.concat dirs.split(File::PATH_SEPARATOR)}
   o.order!(ARGV)
 end
 template = ARGV.shift or abort opt.to_s
@@ -16,7 +30,7 @@ erb = ERB.new(File.read(template), nil, '%')
 erb.filename = template
 result = erb.result
 if output
-  if ifchange and (IO.read(output) rescue nil) == result
+  if ifchange and (vpath.open(output) {|f| f.read} rescue nil) == result
     puts "#{output} unchanged"
   else
     open(output, "wb") {|f| f.print result}