fileutils.rb: fix error message

* lib/fileutils.rb (FileUtils#mv): show the exact target path in
  the error message instead of the destination parent directory
  name.  patched by João Britto <jabcalves AT gmail.com> at
  [ruby-core:68706].  [Bug #11021]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@50141 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ChangeLog

@@ -1,3 +1,10 @@
+Wed Apr  1 09:59:12 2015  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* lib/fileutils.rb (FileUtils#mv): show the exact target path in
+	  the error message instead of the destination parent directory
+	  name.  patched by Joao Britto <jabcalves AT gmail.com> at
+	  [ruby-core:68706].  [Bug #11021]
+
 Tue Mar 31 15:25:07 2015  SHIBATA Hiroshi  <shibata.hiroshi@gmail.com>
 
 	* doc/ChangeLog-0.06_to_0.52: added archived Changelog.

lib/fileutils.rb

@@ -518,7 +518,7 @@ module FileUtils
       begin
         if destent.exist?
           if destent.directory?
-            raise Errno::EEXIST, dest
+            raise Errno::EEXIST, d
           else
             destent.remove_file if rename_cannot_overwrite_file?
           end

test/fileutils/test_fileutils.rb

@@ -416,7 +416,8 @@ class TestFileUtils < Test::Unit::TestCase
 
     mkdir 'tmp/tmpdir'
     mkdir_p 'tmp/dest2/tmpdir'
-    assert_raise(Errno::EEXIST) {
+    assert_raise_with_message(Errno::EEXIST, %r' - tmp/dest2/tmpdir\z',
+                              '[ruby-core:68706] [Bug #11021]') {
       mv 'tmp/tmpdir', 'tmp/dest2'
     }
     mkdir 'tmp/dest2/tmpdir/junk'