Context: GC now only called when the commands request it

src/Context.cpp

@@ -432,9 +432,9 @@ int Context::dispatch (std::string &out)
     Command* c = commands[command];
     assert (c);
 
-    // GC is invoked prior to running any command that displays task IDs, if
-    // possible.
-    if (c->displays_id () && !tdb2.read_only ())
+    // The command know whether they need a GC.
+    if (c->needs_gc () &&
+        ! tdb2.read_only ())
     {
       run_gc = config.getBoolean ("gc");
       tdb2.gc ();

src/commands/CmdProjects.cpp

@@ -59,9 +59,6 @@ int CmdProjects::execute (std::string& output)
 {
   int rc = 0;
 
-  // Enforce the garbage collector to show correct task counts
-  context.tdb2.gc ();
-
   // Get all the tasks.
   handleRecurrence ();
   auto tasks = context.tdb2.pending.get_tasks ();
@@ -74,7 +71,6 @@ int CmdProjects::execute (std::string& output)
   Filter filter;
   std::vector <Task> filtered;
   filter.subset (tasks, filtered);
-
   int quantity = filtered.size ();
 
   std::stringstream out;