stat.writable? incorrectly reporting false for some directories on Windows 7 #3505
Description
In 1.7.22:
irb(main):031:0> dir = File.expand_path(ENV['TMP'])
"C:/Users/ANTHON~1/AppData/Local/Temp"
irb(main):032:0> stat = File.stat(dir)
#<File::Stat dev=0x2, ino=0, mode=040755, nlink=1, uid=0, gid=0, rdev=0x2, size=393216, blksize=512, blocks=0, atime=2015-11-30 18:19:32 -0500, mtime=2015-11-30 18:19:32 -0500, ctime=2015-11-16 11:18:42 -0500>
irb(main):033:0> stat.writable?
true
In 1.7.23:
irb(main):039:0> dir = File.expand_path(ENV['TMP'])
"C:/Users/ANTHON~1/AppData/Local/Temp"
irb(main):040:0> stat = File.stat(dir)
#<File::Stat dev=0x2, ino=0, mode=040555, nlink=1, uid=-1, gid=, rdev=0x2, size=393216, blksize=0, blocks=, atime=2015-11-30 06:45:17 -0500, mtime=2015-11-30 06:45:17 -0500, ctime=2015-11-15 23:43:54 -0500>
irb(main):041:0> stat.writable?
false
I noticed this because it broke Dir.tmpdir on this system: every candidate temp directory is skipped.