From ce3ca270a5433dc1f252c49ba2905e87f2ab2a92 Mon Sep 17 00:00:00 2001
From: usa <usa@b2dd03c8-39d4-4d8f-98ff-823fe69b080e>
Date: Thu, 15 Aug 2013 12:38:02 +0000
Subject: [PATCH] * test/ruby/test_file.rb (TestFile#test_truncate_size): test
 for   above changes.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@42565 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
---
 ChangeLog              |  3 +++
 test/ruby/test_file.rb | 26 ++++++++++++++++++++++++++
 2 files changed, 29 insertions(+)

diff --git a/ChangeLog b/ChangeLog
index 9310cc975d..08f2a63ee5 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -7,6 +7,9 @@ Thu Aug 15 20:51:29 2013  NAKAMURA Usaku  <usa@ruby-lang.org>
 
 	* file.c (rb_file_truncate): use above function.
 
+	* test/ruby/test_file.rb (TestFile#test_truncate_size): test for
+	  above changes.
+
 Thu Aug 15 18:39:31 2013  NAKAMURA Usaku  <usa@ruby-lang.org>
 
 	* win32/win32.c (clock_gettime): improve precision when freq is less
diff --git a/test/ruby/test_file.rb b/test/ruby/test_file.rb
index 528193dabb..50f101867a 100644
--- a/test/ruby/test_file.rb
+++ b/test/ruby/test_file.rb
@@ -1,5 +1,6 @@
 require 'test/unit'
 require 'tempfile'
+require "thread"
 require_relative 'envutil'
 require_relative 'ut_eof'
 
@@ -118,6 +119,31 @@ class TestFile < Test::Unit::TestCase
     }
   end
 
+  def test_truncate_size
+    Tempfile.create("test-truncate") do |f|
+      q1 = Queue.new
+      q2 = Queue.new
+
+      Thread.new do
+        data = ''
+        64.times do |i|
+          data << i.to_s
+          f.rewind
+          f.print data
+          f.truncate(data.bytesize)
+          q1.push data.bytesize
+          q2.pop
+        end
+        q1.push nil
+      end
+
+      while size = q1.pop
+        assert_equal size, File.size(f.path)
+        q2.push true
+      end
+    end
+  end
+
   def test_read_all_extended_file
     [nil, {:textmode=>true}, {:binmode=>true}].each do |mode|
       Tempfile.create("test-extended-file", mode) {|f|