Restore activity metadata

This allows the progress bar to display "building perl-5.22.3" instead
of "building /nix/store/<hash>-perl-5.22.3.drv".

1 files changed, 9 insertions, 1 deletions

diff --git a/src/nix/progress-bar.cc b/src/nix/progress-bar.cc
index f0db3be60..a692250f8 100644
--- a/src/nix/progress-bar.cc
+++ b/src/nix/progress-bar.cc
@@ -93,7 +93,8 @@ public:
         update(state);
     }
 
-    void startActivity(ActivityId act, ActivityType type, const std::string & s) override
+    void startActivity(ActivityId act, ActivityType type, const std::string & s,
+        const Fields & fields) override
     {
         auto state(state_.lock());
 
@@ -102,6 +103,13 @@ public:
         state->its.emplace(act, i);
         state->activitiesByType[type].its.emplace(act, i);
 
+        if (type == actBuild) {
+            auto name = storePathToName(getS(fields, 0));
+            if (hasSuffix(name, ".drv"))
+                name.resize(name.size() - 4);
+            i->s = fmt("building " ANSI_BOLD "%s" ANSI_NORMAL, name);
+        }
+
         update(*state);
     }