commands/package: Nicer error if includes has symlinks [GH-3200]

CHANGELOG.md

@@ -13,6 +13,7 @@ BUG FIXES:
       fail [GH-3391]
   - core: `vagrant` on Windows cmd.exe doesn't always exit with exit
       code zero. [GH-3420]
+  - commands/package: Nice error if includes contain symlinks. [GH-3200]
   - commands/rsync-auto: Don't crash if the machine can't be communicated
       to. [GH-3419]
   - guests/fedora: Fix hostname setting. [GH-3382]

lib/vagrant/action/general/package.rb

@@ -72,6 +72,11 @@ module Vagrant
               FileUtils.cp(from, to, :preserve => true)
             end
           end
+        rescue Errno::EEXIST => e
+          raise if !e.to_s.include?("symlink")
+
+          # The directory contains symlinks. Show a nicer error.
+          raise Errors::PackageIncludeSymlink
         end
 
         # Compress the exported file into a package

lib/vagrant/errors.rb

@@ -456,6 +456,10 @@ module Vagrant
       error_key(:include_file_missing, "vagrant.actions.general.package")
     end
 
+    class PackageIncludeSymlink < VagrantError
+      error_key(:package_include_symlink)
+    end
+
     class PackageOutputDirectory < VagrantError
       error_key(:output_is_directory, "vagrant.actions.general.package")
     end

templates/locales/en.yml

@@ -789,6 +789,10 @@ en:
         You can however, install a plugin with the same name to replace
         these plugins. User-installed plugins take priority over
         system-installed plugins.
+      package_include_symlink: |-
+        A file or directory you're attempting to include with your packaged
+        box has symlinks in it. Vagrant cannot include symlinks in the
+        resulting package. Please remove the symlinks and try again.
       provider_not_found: |-
         The provider '%{provider}' could not be found, but was requested to
         back the machine '%{machine}'. Please use a provider that exists.