uniter, state: handle upgrades better

state/unit_test.go

 package state_test
 
 import (
         . "launchpad.net/gocheck"
         "launchpad.net/juju-core/charm"
         "launchpad.net/juju-core/state"
         "sort"
         "strconv"
         "time"
 )
@@ skipping 22 matching lines @@
         c.Assert(err, ErrorMatches, `unit "subway/0" not found`)
         c.Assert(state.IsNotFound(err), Equals, true)
 }
 
 func (s *UnitSuite) TestService(c *C) {
         svc, err := s.unit.Service()
         c.Assert(err, IsNil)
         c.Assert(svc.Name(), Equals, s.unit.ServiceName())
 }
 
+func (s *UnitSuite) TestServiceConfig(c *C) {
+        scfg, err := s.service.Config()
+        c.Assert(err, IsNil)
+        scfg.Update(map[string]interface{}{
+                "foo":        "bar",

[fwereade, 2013/03/14 10:53:54]

It's evil and wrong that we can do this in the first place, but that's out of
scope.

[dimitern, 2013/03/14 16:14:39]

I agree!

+                "blog-title": "no title",
+        })
+        _, err = scfg.Write()
+        c.Assert(err, IsNil)
+
+        unit, err := s.service.AddUnit()
+
+        _, err = unit.ServiceConfig()
+        c.Assert(err, ErrorMatches, "unit charm not set")
+
+        err = unit.SetCharmURL(s.charm.URL())
+        c.Assert(err, IsNil)
+
+        cfg, err := unit.ServiceConfig()
+        c.Assert(err, IsNil)
+        c.Assert(cfg, DeepEquals, scfg.Map())
+}
+
 func (s *UnitSuite) TestGetSetPublicAddress(c *C) {
         address, ok := s.unit.PublicAddress()
         c.Assert(ok, Equals, false)
         err := s.unit.SetPublicAddress("example.foobar.com")
         c.Assert(err, IsNil)
         address, ok = s.unit.PublicAddress()
         c.Assert(ok, Equals, true)
         c.Assert(address, Equals, "example.foobar.com")
 }
 
@@ skipping 642 matching lines @@
                 c.Fatalf("got unexpected change: %#v, %v", got, ok)
         case <-time.After(100 * time.Millisecond):
         }
 }
 
 func (s *UnitSuite) TestAnnotatorForUnit(c *C) {
         testAnnotator(c, func() (annotator, error) {
                 return s.State.Unit("wordpress/0")
         })
 }