Assume Cygwin has a TTY for input [GH-1430]

CHANGELOG.md

@@ -49,6 +49,7 @@ BUG FIXES:
     that is also in use.
   - Cygwin will always output color by default. Specify `--no-color` to
     override this.
+  - Assume Cygwin has a TTY for asking for input. [GH-1430]
 
 ## 1.1.6 (April 3, 2013)
 

lib/vagrant/ui.rb

@@ -2,6 +2,7 @@ require "thread"
 
 require "log4r"
 
+require "vagrant/util/platform"
 require "vagrant/util/safe_puts"
 
 module Vagrant
@@ -77,7 +78,7 @@ module Vagrant
         super(message)
 
         # We can't ask questions when the output isn't a TTY.
-        raise Errors::UIExpectsTTY if !$stdin.tty?
+        raise Errors::UIExpectsTTY if !$stdin.tty? && !Vagrant::Util::Platform.cygwin?
 
         # Setup the options so that the new line is suppressed
         opts ||= {}