libstore: move Goal::amDone to Worker

we still mutate goal state to store the results of any given goal run,
but now we also have that information in Worker and could in theory do
something else with it. we could return a map of goal to goal results,
which would also let us better diagnose failures of subgoals (at all).

Change-Id: I1df956bbd9fa8cc9485fb6df32918d68dda3ff48

1 files changed, 6 insertions, 4 deletions

diff --git a/src/libstore/build/drv-output-substitution-goal.cc b/src/libstore/build/drv-output-substitution-goal.cc
index 4d10543cd..62e86e1cc 100644
--- a/src/libstore/build/drv-output-substitution-goal.cc
+++ b/src/libstore/build/drv-output-substitution-goal.cc
@@ -26,7 +26,7 @@ Goal::WorkResult DrvOutputSubstitutionGoal::init()
 
     /* If the derivation already exists, we’re done */
     if (worker.store.queryRealisation(id)) {
-        return amDone(ecSuccess);
+        return Finished{ecSuccess};
     }
 
     subs = settings.useSubstitutes ? getDefaultSubstituters() : std::list<ref<Store>>();
@@ -60,7 +60,7 @@ Goal::WorkResult DrvOutputSubstitutionGoal::tryNext()
         /* Hack: don't indicate failure if there were no substituters.
            In that case the calling derivation should just do a
            build. */
-        return amDone(substituterFailed ? ecFailed : ecNoSubstituters);
+        return Finished{substituterFailed ? ecFailed : ecNoSubstituters};
     }
 
     sub = subs.front();
@@ -137,7 +137,9 @@ Goal::WorkResult DrvOutputSubstitutionGoal::outPathValid()
 
     if (nrFailed > 0) {
         debug("The output path of the derivation output '%s' could not be substituted", id.to_string());
-        return amDone(nrNoSubstituters > 0 || nrIncompleteClosure > 0 ? ecIncompleteClosure : ecFailed);
+        return Finished{
+            nrNoSubstituters > 0 || nrIncompleteClosure > 0 ? ecIncompleteClosure : ecFailed
+        };
     }
 
     worker.store.registerDrvOutput(*outputInfo);
@@ -147,7 +149,7 @@ Goal::WorkResult DrvOutputSubstitutionGoal::outPathValid()
 Goal::WorkResult DrvOutputSubstitutionGoal::finished()
 {
     trace("finished");
-    return amDone(ecSuccess);
+    return Finished{ecSuccess};
 }
 
 std::string DrvOutputSubstitutionGoal::key()