Reorder qemu agent usage for use with sessions (#1396)

Adjust the order of checks around use of qemu sessions to allow use of
the agent as a priority when enabled, which should remove the need to
retrieve the address from the system connection when enabled.

Additionally adjust the call to the agent to ensure it uses the default
connection to retrieve the correct domain, rather than forcing the
system connection, which will fail to find the domain if it was created
via a user session.

Add tests that validate most of this behaviour, as well as resulting in
some minor fixes around downcasing the mac address for comparisons, and
also using instance mocks with rspec instead of pure doubles to help
catch false positives where mocks are allowing calls that done exist.

Related: #1342

lib/vagrant-libvirt/config.rb

@@ -970,7 +970,7 @@ module VagrantPlugins
         # Additional QEMU commandline environment variables
         @qemu_env = {} if @qemu_env == UNSET_VALUE
 
-        @qemu_use_agent = true if @qemu_use_agent != UNSET_VALUE
+        @qemu_use_agent = false if @qemu_use_agent == UNSET_VALUE
 
         @serials = [{:type => 'pty', :source => nil}] if @serials == []
       end
@@ -986,6 +986,9 @@ module VagrantPlugins
           end
         end
 
+        unless @qemu_use_agent == true || @qemu_use_agent == false
+          errors << "libvirt.qemu_use_agent must be a boolean."
+        end
 
         if @qemu_use_agent == true
           # if qemu agent is used to optain domain ip configuration, at least

lib/vagrant-libvirt/driver.rb

@@ -98,16 +98,16 @@ module VagrantPlugins
       end
 
       def get_domain_ipaddress(machine, domain)
-        if @machine.provider_config.qemu_use_session
-          return get_ipaddress_from_system domain.mac
-        end
-
         # attempt to get ip address from qemu agent
         if @machine.provider_config.qemu_use_agent == true
           @logger.info('Get IP via qemu agent')
           return get_ipaddress_from_qemu_agent(domain, machine.id)
         end
 
+        if @machine.provider_config.qemu_use_session
+          return get_ipaddress_from_system domain.mac
+        end
+
         # Get IP address from dhcp leases table
         begin
           ip_address = get_ipaddress_from_domain(domain)
@@ -168,9 +168,9 @@ module VagrantPlugins
       def get_ipaddress_from_qemu_agent(domain, machine_id)
         ip_address = nil
         addresses = nil
-        dom = system_connection.lookup_domain_by_uuid(machine_id)
+        libvirt_domain = connection.client.lookup_domain_by_uuid(machine_id)
         begin
-          response = dom.qemu_agent_command('{"execute":"guest-network-get-interfaces"}', timeout=10)
+          response = libvirt_domain.qemu_agent_command('{"execute":"guest-network-get-interfaces"}', timeout=10)
           @logger.debug("Got Response from qemu agent")
           @logger.debug(response)
           addresses = JSON.parse(response)
@@ -180,7 +180,7 @@ module VagrantPlugins
 
         unless addresses.nil?
           addresses["return"].each{ |interface|
-            if domain.mac == interface["hardware-address"]
+            if domain.mac.downcase == interface["hardware-address"].downcase
               @logger.debug("Found mathing interface: [%s]" % interface["name"])
               if interface.has_key?("ip-addresses")
                 interface["ip-addresses"].each{ |ip|