In-house patch to fix upstream bug PUP-5234 which adds attrible "shell" to the user provider.
https://tickets.puppetlabs.com/browse/PUP-5234
The patch has been submitted upstream but not yet accepted.

--- puppet-3.6.2/lib/puppet/provider/user/user_role_add.rb.orig  Thu Jul 30 22:51:24 2015
+++ puppet-3.6.2/lib/puppet/provider/user/user_role_add.rb	Mon Aug  3 23:22:44 2015
@@ -12,6 +12,7 @@
   options :home, :flag => "-d", :method => :dir
   options :comment, :method => :gecos
   options :groups, :flag => "-G"
+  options :shell, :flag => "-s"
   options :roles, :flag => "-R"
   options :auths, :flag => "-A"
   options :profiles, :flag => "-P"
@@ -26,8 +27,23 @@
     value !~ /\s/
   end
 
+  def shell=(value)
+    check_valid_shell
+    set("shell", value)
+  end
+
   has_features :manages_homedir, :allows_duplicates, :manages_solaris_rbac, :manages_passwords, :manages_password_age
+  has_features :manages_shell
 
+  def check_valid_shell
+    unless File.exists?(@resource.should(:shell))
+      raise(Puppet::Error, "Shell #{@resource.should(:shell)} must exist")
+    end
+    unless File.executable?(@resource.should(:shell).to_s)
+      raise(Puppet::Error, "Shell #{@resource.should(:shell)} must be executable")
+    end
+  end
+
   #must override this to hand the keyvalue pairs
   def add_properties
     cmd = []